I suoli: aspetti abiotici e biotici

Cellulolytic bacteria joined with deproteinized whey decrease carbon to nitrogen ratio and improve stability of compost from wine production chain by-products

Composting residues from wine and dairy chains would contribute to increase the environmental sustainability of the production. The aim of this study was to evaluate the effects of deproteinized whey combined with bioactivators on the composting process. Bacillus velezensis and Kocuria rhizophila, bacteria with cellulolytic activity, were isolated from raw materials and inoculated in the organic mass to be composted. Piles moistened with deproteinized whey showed the highest reduction of total and dissolved organic carbon due to the stimulation of bacterial activity by nitrogen compounds held within deproteinized whey. Such findings were also confirmed by the speed up of the microbial carbo…

Microbial characterisation of fermented meat productions from the Sicilian breed "Suino Nero dei Nebrodi"

Two traditional sausage products (“salsiccia” and “salame”) processed from the raw meat of the Black Sicilian swine “Suino Nero dei Nebrodi” were microbiologically investigated during the manufacturing and ripening stages. Both products were dominated by lactic acid bacteria (LAB), especially rod-shaped types. The concentration of enterococci was consistent in salame. Coagulase-negative cocci increased slower than LAB. Yeasts showed an increasing trend during the ripening of both products. Enterobacteriaceae were counted at a constant level of about 105 CFU/g in both products, while pseudomonads diminished during ripening. Coagulase-positive staphylococci, Listeria monocytogenes and Salmone…

Use of nodulation pattern, stress tolerance, nodC gene amplification, RAPD-PCR and RFLP-16S rDNA analysis to discriminate genotypes of Rhizobium leguminosarum biovar viciae

Twenty-seven new Rhizobium isolates were obtained from root nodules of wild and crop legumes belonging to the genera Vicia, Lathyrus and Pisum from different agroecological areas in central and southern Italy. A polyphasic approach including phenotypic and genotypic techniques was used to study their diversity and their relationships with other biovars and species of rhizobia. Analysis of symbiotic properties and stress tolerance tests revealed that wild isolates, showed a wide spectrum of nodulation and a marked variation in stress tolerance compared with reference strains tested in this study. All rhizobial isolates (except for the isolate CG4 from Galega officinalis) were presumptively i…

PCR-DGGE fingerprints of microbial succession during a manufacture of traditional water buffalo mozzarella cheese.

D . E R C O L I N I , G . M A U R I E L L O , G . B L A I O T T A , G . M O S C H E T T I A N D S . C O P P O L A . 2003. Aims: To monitor the process and the starter effectiveness recording a series of fingerprints of the microbial diversity occurring at different steps of mozzarella cheese manufacture and to investigate the involvement of the natural starter to the achievement of the final product. Methods and Results: Samples of raw milk, natural whey culture (NWC) used as starter, curd after ripening and final product were collected during a mozzarella cheese manufacture. Total microbial DNA was directly extracted from the dairy samples as well as bulk colonies collected from the plates…

The migratory birds: novel ecological niche of fungal diversity?

Francesca et al (2010) studied the ecology of wine yeasts associated to birds caught in vineyards. The same authors were able to prove that migratory birds might carry living pro-technological yeasts for about 12 hours from the ingestion of inoculated feed (Francesca et al 2012). In subsequent studies, they tried to demonstrate that microorganisms are not only transported for a short period by birds, but microorganisms might be adapted to the specific conditions (body temperature about 42 °C and low pH) of the intestinal tract of birds. Hence, it was demonstrated that the majority of isolates carried by birds are thermotolerant. The most interesting results were the isolation of two new spe…

Effect of agricultural practices on soil microbial communities

Soil carbon sequestration is an important and immediate sink for removing atmospheric carbon dioxide and slowing global warming. Agricultural practices strongly impact CO2 emission from the soil and the loss of soil organic matter is lower when “no-till” agriculture is practiced. The present work was performed in order to investigate effects of different agricultural practices on soil microbial communities. Field experiments took place at three Italian locations strongly differing in pedological, chemical and climatic characteristics: Naples, Turin and Piacenza. Soils were subjected to four management practices such as traditional (TRA), minimum tillage (MIN) and amendments with compost (CO…

Investigation of a tunnel pasteurizer for “Nocellara del Belice” table olives processed according to the “Castelvetrano method”

The influence of pasteurization temperature and time of treatment on the flesh firmness and the evolution of microbial communities was studied for table olives Cv. Nocellara del Belice, packed in glass jars and processed with a tunnel pasteurizer. The experiment was first carried out on the laboratory level in order to select the optimal combination of pasteurization time/temperature so as to obtain the proper balance between the consistency of the pulp and the microbiological quality of the final product. Pasteurization at industrial scale was then carried out in a tunnel pasteurizer applying the treatment at 75 °C for 8 min in the thermal center of the jars. Besides flesh firmness and mic…

Characteristics of sourdoughs and baked pizzas as affected by starter culture inoculums

Previous investigations on pizza dough lactic acid bacteria (LAB) revealed that facultative heterofermentative species (FHS) were more represented than obligate heterofermentative species (OHS) within the Lactobacillus genus. Thus, the main hypothesis of this work was that facultative and obligate heterofermentative Lactobacillus species can impact differently the appreciation of baked pizza. The performances of different Lactobacillus, including L. sanfranciscensis, L. brevis and L. rossiae among OHS and L. plantarum, L. graminis and L. curvatus among FHS were tested in single or multiple combinations during pizza production. The values of pH, total titratable acidity and LAB levels indica…

Effect of the mechanical harvest of drupes on the quality characteristics of green fermented table olives

Background: Because of damage caused by mechanical harvesting, the drupes for table olive production are traditionally hand harvested. Until now, no data have been available on the microbiological and chemical features of mechanically harvested drupes during fermentation. Results: Drupes mechanically harvested and inoculated with Lactobacillus pentosus OM13 were characterized by the lowest concentrations of potential spoilage microorganisms. On the other hand, drupes mechanically harvested and subjected to spontaneous fermentation showed the highest concentration of Enterobacteriaceae and pseudomonads during transformation. The lowest decrease of pH (4.20) was registered for the trials inoc…

NMR spectroscopy evaluation of direct relationship between soils and molecular composition of red wines from Aglanico grapes

1H NMR spectroscopy was employed to investigate the molecular quality of Aglianico red wines from the Campania region of Italy. The wines were obtained from three different Aglianico vineyards characterized by different microclimatic and pedological properties. In order to reach an objective evaluation of “terroir” influence on wine quality, grapes were subjected to the same winemaking procedures. The careful subtraction of water and ethanol signals from NMR spectra allowed to statistically recognize the metabolites to be employed in multivariate statistical methods: Principal Component Analysis (PCA), Discriminant Analysis (DA) and Hierarchical Clustering Analysis (HCA). The three wines we…

Microbiological and chemical monitoring of Marsala base wine obtained by spontaneous fermentation during large-scale production

The present work was undertaken to evaluate the effect of natural wine making on the microbial and chemical composition of Marsala base wine. To this purpose, a large-scale vinification process of Grillo grape cultivar was monitored from the grape harvest to the final product. Total yeasts (TY) showed a rapid increase after must pressings and reached values that were almost identical to those registered during conventional wine makings. Lactic acid bacteria (LAB) were registered at the highest levels simultaneous to those of yeast growth at the beginning of the process. Saccharomyces cerevisiae was the species found at the highest concentrations in all samples analysed. Several strains (n =…

Studio sulla relazione tra la resistenza alla kanamicina ed il gene “Putative aminoglycoside 3’-phosphotranferase (PAPH) in Sinorhizobium meliloti ceppo 1021

Il ceppo selvatico di Sinorhizobium meliloti 1021 è sensibile alla kanamicina (30 mg/l) anche se Capela et al. (Proc. Natl. Acad. Sci. U.S.A.(2001), 98: 9877-9882), analizzando l’intero genoma, hanno trovato un gene codificante per una “putative aminoglycoside 3'-phosphotransferase” (PAPH), coinvolta nella resistenza ad antibiotici aminoglicosidici quali la kanamicina. Un mutante spontaneo (GM42) kanamicina resistente (200 mg/l) di Sinorhizobium meliloti 1021 è stato caratterizzato da un punto di vista molecolare e fenotipico per analizzare l’attività del gene PAPH. Il ceppo parentale e GM42 sono stati caratterizzati da un punto di vista microbiologico tramite il MicroLog System Biolog. I r…

Investigation of yeast community of “Grillo” grapes and musts from Marsala wine production area.

The oenological interest in the autochthonous yeast applications has increased since they represents an important supplement to wine quality (Martinez et al. 1989; Moreno et al. 1991). Yeast populations harboured onto the surface of berries and in musts of “Grillo” grape variety were isolated and analyzed. In order to obtain a first blastomycetic mapping of Marsala wine production area, eight vineyards were chosen on the basis of different climatic and agronomic parameters, including altitude, exposure,vineyard age, grape biotype, grape cultivation system, vegetative vigour, pruning, green pruning, yield per plant, phytosanity state, irrigation and closeness to wood areas. Analysis of blast…

Enteric bacteria of food ice and their survival in alcoholic beverages and soft drinks

This study aimed to evaluate the levels of enteric bacteria in ice cubes produced in different environments (home-made, prepared in bars and pubs with ice machines and produced in industrial plants) and to determine their survival in different alcoholic beverages and soft drinks. Members of the Enterobacteriaceae family were found in almost all samples analysed. All industrial and the majority of home-made samples did not contain coliforms. Enterococci were not identified in domestic samples while they were detected in two industrial and three bar/pub samples. The samples collected from bars and pubs were characterized by the highest levels of enteric bacteria. Fourteen strains representing…

Microbiological Profile and Bioactive Properties of Insect Powders Used in Food and Feed Formulations

Microbiological, nutritional and bioactive properties of edible powders obtained from Acheta domesticus (house cricket) and Tenebrio molitor (mealworm) were investigated. Except for the enterobacteria, viable bacteria were at a higher concentration in mealworm flour. The diversity evaluation carried out using MiSeq Illumina that mainly identified Citrobacter and Enterobacteriaceae in mealworm powder and members of the Porphyromonadaceae family in house cricket powder. Enterococci were identified and characterized for their safety characteristics in terms of the absence of antibiotic resistance and virulence. Both powders represent a good source of proteins and lipids. The fatty acid profile…

I lieviti del Vino Fiano di Avellino DOCG: la tipicità attraverso le biotecnologie

I microrganismi caratteristici di un prodotto tipico fermentato come il vino, dai quali dipendono molte delle proprietà organolettiche, riflettono, in molti casi, le caratteristiche dell’ambiente e dei sistemi di produzione. Infatti, i prodotti alimentari di nicchia legano la loro storia alla zona di produzione non solo per le tradizioni che si tramandano nel tempo, ma anche e soprattutto per la presenza di specie e ceppi di microrganismi che colonizzano la materia prima, nonché gli ambienti e le attrezzature di lavorazione, contribuendo in maniera decisiva a caratterizzare la tipicità del prodotto finale. Nello spirito delle “Denominazioni d’Origine”, particolare importanza deve essere anc…

Effetti della lunga macerazione post-fermentativa sulla composizione fenolica e microbiologica del vino Aglianico di Taurasi

Soil solarization with biodegradabile materials and its impact on soil microbial communities.

Soil solarization (SS) seems one of the most promising techniques to control soilborne pathogens, but an important limitation to the diffusion of this technique is due to the drawback regarding the disposal of the used plastic materials. A possible solution to this problem is the use of biodegradable plastics. The aim of this study was compare the impact of SS with biodegradable materials with SS with plastic film and others pest management techniques (i.e. organic matter amendment, calcium cyanamide and Dazomet fungicide application) on crop productivity, soilborne disease incidence, weed suppression, and soil chemical (total N, ammonium, nitrate, available phosphorus, organic matter, hydr…

Microbiological investigation of Raphanus sativus L. grown hydroponically in nutrient solutions contaminated with spoilage and pathogenic bacteria

Abstract The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114T) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.…

Evaluation of antimicrobial resistance and virulence of enterococci from equipment surfaces, raw materials and traditional cheeses

Forty enterococci isolated along the production chains of three traditional cheeses (PDO Pecorino Siciliano, PDO Vastedda della Valle del Belìce, and Caciocavallo Palermitano) made in Sicily (southern Italy) were studied for the assessment of their antibiotic resistance and virulence by a combined phenotypic/genotypic approach. A total of 31 Enterococcus displayed resistance to at least one or more of the antimicrobials tested. The strains exhibited high percentages of resistance to erythromycin (52.5%), ciprofloxacin (35.0%), quinupristin–dalfopristin (20.0%), tetracycline (17.5%), and high-level streptomycin (5.0%). The presence of tet(M), cat(pC221), and aadE genes for resistance to tetr…

Detection of endophytic bacteria in leaves of Vitis vinifera by using fluorescence in situ hybridization

Previous investigation on five cultivars of healthy Sicilian grapevine allowed the isolation of endophytic bacteria belonging to Bacillus genus from different organs (bud, leaf, stalk and shoot). The aim of this work was to use fluorescence in situ hybridization (FISH) experiments in healthy and damaged leaf tissues of Vitis vinifera to visualize and localize bacteria associated with plant materials. The leaves were cleared to minimize the autofluorescence of the plant fragments. The use of fluorescently labelled bacterial probe Eub338 in FISH experiments on discoloured grapevine leaf disks allowed the estimation of the spatial distribution of different bacterial colonies. At the same time,…

Development of an ad hoc natural whey starter culture for the production of Vastedda della valle del Belìce cheese

This work was aimed to characterize the autochthonous lactic acid bacteria (LAB) of PDO Vastedda della valle del Belìce cheeses, produced in several dairy factories, for the development of an ad hoc starter culture preparation for the production of this cheese. To this purpose, winter and spring productions were analysed, in order to isolate LAB adapted to perform the fermentation at low temperatures. Plate counts showed the total microbial counts (TMC) till levels of 9 -1almost 10 CFU g and all cheese samples were dominated by coccus LAB. Not all samples were positive for the presence of enterobacteria, but when they were found their concentrations were at similar levels in both seasons. A…

APPLICATION OF SELECTED LACTIC ACID BACTERIA FOR THE YEAR-ROUND PRODUCTION OF VASTEDDALIKE CHEESE

Approccio multiplo per l’indagine del microbiota dominante negli impasti acidi tradizionali siciliani

Development of in vitro screening of EPS producing LAB for cereal based products.

Antifungal peptides produced by Bacillus amyloliquefaciens AG1 active against grapevine fungal pathogens

Abstract Antifungal metabolites produced by Bacillus amyloliquefaciens AG1, previously isolated from wood of grapevine with “esca syndrome”, were studied. The crude protein extract (CPE) obtained from culture supernatant fluid by precipitation with ammonium sulfate was assayed against many grapevine fungal pathogens. B. amyloliquefaciens strain AG1 showed a broad spectrum of antifungal activity, inhibiting mycelial growth in vitro of all tested fungal microorganisms. The metabolites contained in CPE were heat stable and remained active over a wide pH range (2–10). Their activity was not affected by proteolytic or glycolytic enzymes. Tricine- SDS-polyacrylamide gel electrophoresis revealed a…

Microbial interactions in food model systems: In situ antilisterial activity of mundticin KS producing strains

It is known that microbial interactions are important for the success of food fermentations, as well as for the establishment of the safety of the final products. In this study, we characterized extensively three enterococci (WFE3, WFE20 and WFE31) of flour origin, which were found to be active against Listeria monocytogenes, in order to investigate on their ability to produce bacteriocins in complex food model systems for their future industrial/food applications. The identification of the three bacterial isolates was performed by means of a combined 16S rRNA gene sequencing and multiplex PCR approach. Two isolates belonged unequivocally to the species E. mundtii, while one isolate could n…

Evaluation of proteolytic, lypolitic and decarboxylase activity of estremely halophilic bacteria occurring in ripening of salt anchovies.

Fermented Honey and Manna Ash Products: Novel Ecological Niches of Wine Yeasts

The selection of novel strains of yeasts is still relevant to improve flavour of wines produced around the word. Several food niches have not been microbiologically investigated and they might represent important sources of microorganisms with technological aptitudes, e.g. in wine industry. To this purpose, two novel yeast communities associated with matrices rich in carbohydrates and characterized by low levels of water activity (aw), such as fermented honey by-products (FHP) and “Manna” ash products (MAP) extracted from Fraxinus angustifolia (Oleaceae), were investigated. FHP contain mainly fructose and glucose, while MAP ash is mainly characterized by high concentrations of mannitol, fru…

Technological screening and application of Saccharomyces cerevisiae strains isolated from fermented honey by-products for the sensory improvement of Spiritu re fascitrari, a typical Sicilian distilled beverage

“Spiritu re fascitrari” is a Sicilian alcoholic beverage obtained through distillation of a decoction of spontaneously fermented honey by-products (FHP). The production process often leads to sensorial defects due to the unstable alcoholic fermentation. The objective of this work was to select Saccharomyces cerevisiae strains from FHP to be used as starter in decoction fermentation. Based on chemical, microbiological and technological data, from a total of 91 strains three S. cerevisae were selected for further testing to produce FHP at laboratory scale level. After FHP distillation, the analysis of volatile organic compounds showed a complex mixture of sensory active molecules, mainly alco…

A simple and rapid DNA extraction method from leaves of grapevine suitable for polymerase chain reaction analysis.

The genomic grapevine (Vitis vinifera L.) DNA extraction is difficult because of secondary metabolites that interfere with DNA isolation procedures and subsequent applications. We developed a simple, rapid and efficient method for the extraction of genomic DNA from asymptomatic and pathogen-infected grape leaves. The protocol reported, based on a modified cetyl trimethylammonium bromide (CTAB) extraction procedure, allowed the rapid DNA extraction from little amounts of leaf material without employment of liquid nitrogen for initial tissue grinding. The protocol included polyvinylpyrrolidone (PVP) to bind phenolic compounds, β-mercaptoethanol to inhibit the oxidation of polyphenols, and a h…

Elementi di Microbiologia del suolo

Questo capitolo riassume i concetti fondamentali di Microbiologia del suolo spiegando quale ruolo svolge la microflora tellurica per il mantenimento della fertilità biologica del terreno. Dopo una introduzione all'ambiente suolo dal punto di vista microbico, viene spiegato il concetto di fertilità biologica del suolo e quale ruolo hanno i microrganismi per il suo mantenimento. Il terzo paragrafo descrive la rete trofica nel suolo e il ruolo che rivestono mesofauna e microflora nella solubilizzazione degli elementi nutritivi. Segue una descrizione dei processi di degradazione della sostanza organica del suolo, con cenni sulle microflore coinvolte. Il suolo in presenza di radici costituisce u…

Seasonal variations of antimicrobial activity and chemical composition of essential oils extracted from three Citrus limon L. Burm. cultivars

In order to investigate the seasonal variations of antimicrobial properties and chemical composition of essential oils (EOs), three different cultivars of Citrus limon L. Burm. spp. (Femminello Santa Teresa, Monachello and Femminello Continella) were collected at 6-week intervals, from December 2012 to April 2013, for a total of four harvests. The EOs were extracted from lemon peel by hydro-distillation. The antimicrobial activity, tested by paper disc diffusion method, was evaluated against common food-related pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Enterobacter spp.). EOs were more effective against Gram-positive than Gram-negative bacte…

Filamentous fungi transported by birds during migration across the mediterranean sea.

The potential for the transport and diffusion of some pathogenic microorganisms by migratory birds is of concern. Migratory birds may be involved in the dispersal of microorganisms and may play a role of mechanical and biological vectors. The efficiency of dispersal of pathogenic microorganisms depends on a wide range of biotic and abiotic factors that influence the survival or disappearance of a given agent in a geographical area. In the present study, 349 migratory birds were captured in four sites (Mazara del Vallo, Lampedusa, Ustica and Linosa), representing the main stop-over points during spring and autumnal migration, and analyzed for the presence of filamentous fungi. A total of 2,3…

Study of green Sicilian table olive fermentations through microbiological, chemical and sensory analyses.

The production of five different green table olive cultivars was studied by a combined strategy consisting of chemical, microbiological and sensory analyses. Cultivable microflora of samples collected during processing was monitored by plate counts on seven synthetic culture media. In all samples Enterobacteriaceae, Pseudomonaceae, staphylococci, lactic acid bacteria and spore-forming bacteria were undetectable. Yeasts and moulds were countable from the day 42 (2 log CFU/ml) till the end of fermentation (6 log CFU/ml). The use of three different approaches for microorganism detection, including a culture-independent methodology, revealed the presence of barely three yeast species during the…

Cultivable microorganisms associated with honeys of different geographical and botanical origin

In this study, the composition of the cultivable microbial populations of 38 nectar honey and honeydew honey samples of different botanical and geographical origin were assessed. After growth in specific media, various colonies with different appearance were isolated and purified before phenotypic (morphological, physiological and biochemical traits) and genotypic [randomly amplified polymorphic DNA (RAPD), repetitive DNA elements-PCR (rep-PCR) and restriction fragment length polymorphism (RFLP)] differentiation. The identification was carried out by 16S rRNA gene sequencing for bacteria and, in addition to RFLP, by sequencing the D1/D2 region of the 26S rRNA gene for yeasts and the 5.8S-IT…

Selenium bio-enrichment of Mediterranean fruit juices through lactic acid fermentation.

Abstract This work was carried out to elaborate selenium (Se) bio-enriched fermented Mediterranean fruit juices. To this purpose, pomegranate and table red grape juices were added with sodium selenite (Na2SeO3) and fermented by Levilactobacillus brevis CRL 2051 and Fructobacillus tropaeoli CRL 2034 individually or combined. To better evaluate the effect of selenite addition and starter strain inoculums on the total bacterial community of the fruit juices, fermentation trials were performed with raw and pasteurized fruit juices. No statistical significant differences were observed for total mesophilic microorganisms (TMM) and rod-shaped lactic acid bacteria (LAB) levels among raw and pasteur…

Formation and Characterization of Early Bacterial Biofilms on Different Wood Typologies Applied in Dairy Production

ABSTRACT The main hypothesis of this work was that Sicilian forestry resources are suitable for the production of equipment to be used in cheese making and indigenous milk lactic acid bacteria (LAB) are able to develop stable biofilms providing starter and nonstarter cultures necessary for curd fermentation and cheese ripening, respectively. Hence, the present work was carried out with deproteinized whey to evaluate LAB biofilm formation on different woods derived from tree species grown in Sicily. Microbiological and scanning electron microscopy analyses showed minimal differences in microbial levels and compositions for the neoformed biofilms. The specific investigation of Salmonella spp.…

Diversity of Rhizobium leguminosarum biovar viciae strains nodulating wild and crop legumes in central-southern Italy.

Effect of Salt Concentration and Extremely Halophilic Archaea on the Safety and Quality Characteristics of Traditional Salted Anchovies

Extremely halophilic archaea (EHA) might play an important role in salted fish production. So far, limited information has been available on the effect of EHA and salt concentration on the safety and quality characteristics of salted anchovies. Eight Halobacterium salinarum strains were isolated from different sea salt samples and subjected to phenotypic and genotypic characterization. The strains were then inoculated into fresh salt before addition to anchovies. A total of 18 experimental productions were performed. The inoculated trials showed the lowest counts of undesired microorganisms. In particular, salted anchovies produced with Hbt. salinarum H11 showed the lowest histamine concent…

Evaluation of microbial diversity during the manufacture of Fior di Latte di Agerola, a traditional raw milk pasta-filata cheese of the Naples area

Microbial diversity of the raw milk for the production of Fior di Latte di Agerola and its changes during cheesemaking were studied. Viable counts showed that at the end of curd ripening, loads of lactic acid bacteria, both mesophilic and thermophilic rods and cocci, higher than those commonly evidenced in similar cheeses produced by using natural or commercial starters, were detected. Identification of 272 isolates, supported by molecular diagnostic aids, evidenced representative cultures of a high number of bacterial taxa of interest as participating in the process, although most of the isolates belonged to Lactococcus lactis and Lactobacillus helveticus species. RAPD-PCR and REA-PFGE bio…

The Wine: typicality or mere diversity? The effect of spontaneous fermentations and biotic factors on the characteristics of wine

Abstract Wine is probably one of the main fermented beverages for which the recognition of the “territoriality” is fundamental for its appreciation. The sensory profile of wine is significantly affected by microbial activities, and indigenous microorganisms may significantly contribute to the expression of wine typicality. The microbial ecology of wines is complex and includes several species and strains of yeasts, bacteria and molds. Several works showed the positive effects of spontaneous fermentations on the quality of wine as a consequence of the growth of different species and/or strains together at high levels. Furthermore, a new style of “natural” winemaking is gaining importance, si…

Use of grape racemes from Grillo cultivar to increase the acidity level of sparkling base wines produced with different Saccharomyces cerevisiae strains

The most important oenological characteristics of high-quality sparkling wines are aromatic aspect, taste persistence, perlage, high levels of acidity and low pH. Due to hot climate and reduced rainfall that characterize Sicily region, white grape varieties such as Grillo cultivar cultivated in this area are characterized by very low concentrations of malic and tartaric acids. Grillo cultivar is characterized by an intense production of raceme grapes with low pH and high content of tartaric and malic acids. These fruits possess the chemical properties useful to increase the amounts of acids in the final wines. With this in mind, the present research was carried out to test the ability of fo…

Identification, typing, and investigation of the dairy characteristics of lactic acid bacteria isolated from 'Vastedda della valle del Belìce' cheese

Traditional cheeses made without starter cultures can be characterised by the attribute of instability. The addition of autochthonous starter cultures can ensure stability without compromising the characteristics of the final product. This study aimed to characterise the autochthonous lactic acid bacteria (LAB) population in “Vastedda della valle del Belice” cheeses, which have a protected designation of origin (PDO) status, in order to develop an ad hoc starter culture to be used in its future production. Winter and spring productions were analysed to ensure isolation of specific LAB that had adapted to perform fermentation at low temperatures. Plate counts revealed total microbial numbers…

Influence of Citrus Essential Oils on the Microbiological, Physicochemical and Antioxidant Properties of Primosale Cheese

The aim of this study was to produce a fresh ovine pressed cheese within Pecorino “Primosale” typology with the addition of citrus essential oils (EOs). For this purpose, ewe’s pasteurized milk was added with EOs from the peel of lemons, oranges and tangerines. Seven cheese productions were performed at the pilot plant scale level, including one control production (CP) without the addition of EOs and six experimental productions obtained by the addition of two EO concentrations (100 and 200 µL/L) to milk. The acidification process was obtained by means of the starter cultures Lactococcus lactis CAG4 and PON36. All cheeses showed levels of lactic acid bacteria (LAB) a…

Inhibition of foodborne pathogen bacteria by essential oils extracted from citrus fruits cultivated in Sicily

Abstract The antagonistic activity of the essential oils (EOs) extracted by hydrodistillation from the fruit peel of several citrus genotypes (pummelo, grapefruit, orange, kumquat, mandarin and lemon) was evaluated against foodborne pathogen bacteria (43 strains of Listeria monocytogenes , 35 strains of Staphylococcus aureus and 14 strains of Salmonella enterica ). Five commercial EOs were used for comparison. Most of the EOs were more effective against the Gram-positive bacteria rather than Salmonella . EOs of lemon genotypes 14 and 15 showed the best results in terms of number of strains inhibited and width of the inhibition zone. The most susceptible strain of each species ( L. monocytog…

Microbiological and physicochemical profile of sugar added ewe’s Ricotta during storage

The microbiological and physicochemical traits of fresh ewe’s Ricotta made with (40% w/w) and without sucrose were investigated. Sugar added Ricotta (SAR) andcontrol Ricotta (CTR) were packaged and stored at 4°C for 90 d. Salmonella spp., Listeria monocytogenes,Escherichia coli, coagulase positive staphylococci, Enterobacteriaceae, total coliforms, Pseudomonas, yeasts, moulds and clostridia were undetectable during the entire monitoring. Total mesophilic and psychrotrophic microorganisms and mesophilic cocci lactic acid bacteria increased over time,but their development was limited in SAR production. The acidificationwas observed only for CTR. Water activity was consistently low(0.897 on av…

Le proprietà sensoriali delle birre artigianali legate ai microrganismi della fermentazione

Yeast dynamics during a spontaneous white wine fermentation.

Microbial dynamics in durum wheat kernels during aging

In the present work the microbial dynamics in wheat kernels were evaluated over time. The main aim of this research was to study the resistance of lactic acid bacteria (LAB) and yeasts associated to unprocessed cereals used for bread making during long term conservation. To this purpose four Triticum durum Desf. genotypes including two modern varieties (Claudio and Simeto) and two Sicilian wheat landraces (Russello and Timilia) were analysed by a combined culture-independent and -dependent microbiological approach after one, two or three years from cultivation and threshing. DNA based MiSeq Illumina technology was applied to reveal the entire bacterial composition of all semolina samples. T…

Effects of different yeast strains, nutrients and glutathione-rich inactivated yeast addition on the aroma characteristics of Catarratto wines

Catarratto is one of the most common non-aromatic white grape varieties cultivated in Sicily (Southern Italy). In order to improve the aromatic expression of Catarratto wines a trial was undertaken to investigate the effect of yeast strain, nutrition and reduced glutathione. Variables included two Saccharomyces cerevisiae strains, an oenological strain (GR1) and one isolated from honey by-products (SPF52), three different nutrition regimes (Stimula Sauvignon Blanc™ (SS), Stimula Chardonnay™ (SC) and classic nutrition practice), and a specific inactivated yeast rich in reduced glutathione to prevent oxidative processes [Glutastar™ (GIY)] ensuing in ten treatments (T1-T10). Microbiological an…

Salvaguardia della tradizione casearia: indagine microbiologica sulla lavorazione tradizionale del Caciocavallo Palermitano

Microbial Activation of Wooden Vats Used for Traditional Cheese Production and Evolution of Neoformed Biofilms.

ABSTRACT Three Lactococcus lactis subsp. cremoris strains were used to develop ad hoc biofilms on the surfaces of virgin wooden vats used for cheese production. Two vats (TZ) were tested under controlled conditions (pilot plant), and two vats (TA) were tested under uncontrolled conditions (industrial plant). In each plant, one vat (TA1 and TZ1) was used for the control, traditional production of PDO Vastedda della Valle del Belìce (Vastedda) cheese, and one (TA2 and TZ2) was used for experimental production performed after lactococcal biofilm activation and the daily addition of a natural whey starter culture (NWSC). Microbiological and scanning electron microscopy analyses showed differenc…

Insights Into the Cultivable Microbial Ecology of “Manna” Ash Products Extracted From Fraxinus angustifolia (Oleaceae) Trees in Sicily, Italy

Microbial communities characterizing a specific food matrix, generally, strongly contribute to both its composition, and properties for food applications. To our knowledge, this is the first study to investigate the cultivable microbial ecology of Sicilian "Manna" ash products in order to acquire new information on the hygienic quality, shelf-life and potential application of this traditional food. To this purpose, several manna samples belonging to different commercial categories were collected and subjected to the analysis of bacteria, yeasts, and filamentous fungi. Furthermore, an investigation of the sugar content and physicochemical parameters was performed. The results of our study fo…

An Optimized and Rapid DNA Extraction Method From Leaves of Grapevine Suitable for PCR-DGGE Based Analysis

Molecular techniques and genetic studies require a fair amount of DNA of high quality in order to produce reliable and clear results (Li et al., 2007). In grapevine, the yield and quality of DNA can be significantly affected by secondary metabolites such as polyphenols, polysaccharides and tannins, that may be consistently abundant during the different stages of leaf development (Iandolino et al., 2004). The development of a simple, rapid and reliable method for the extraction of genomic DNA from grape leaves collected at several stages during development, as well as from healthy grape leaves and leaves infected by pathogenic microorganisms, was the main objective of this study. The protoco…

Effetto antimicrobico della componente volatile dell’olio essenziale di mandarino.

Gli oli essenziali, estratti dalle piante, sono composti lipofili contenenti una ampia varietà di elementi volatili. Vengono normalmente ottenuti per distillazione o estrazione con solventi. Trovano impiego nella preparazione di cosmetici, per aggiungere sapore ai cibi e alle bevande e per la formulazione di profumi sia personali che per l’ambiente. Gli oli essenziali hanno recentemente trovato impiego nelle biotecnologie applicate al settore agroalimentare. Sono stati, infatti, utilizzati per ottimizzare le proprietà nutrizionali degli alimenti e per prolungarne la shelf life [1,2]. Gli oli essenziali ottenuti da mandarino sono tradizionalmente usati come antidolorifici, sedativi e curativ…

Rovello bianco, caratterizzazione di un vitigno autoctono campano.

Il “Rovello bianco”, conosciuto localmente come “Greco muscio” nuovo vitigno autoctono campano è stato oggetto di uno studio triennale (2004-2005) considerando il “Fiano” come varietà di riferimento. L’analisi molecolare mediante marcatori micro satelliti (SSR) ne ha stabilito l’unicità del profilo genetico. La valutazione agronomica è stata ottenuta attraverso annuali e sistematici rilievi, effettuati su 50 piante di 5 anni di età, registrando da parte del “Rovello bianco” un più basso vigore vegetativo rispetto al “Fiano” e una buona resistenza alle più diffuse fitopatie. Ben distinta dal vino “Fiano” è risultata invece la componente organica volatile. Principalmente alcoli isoamilici qua…

Fungal and bacterial endophytes in Olea europaea.

The composition of the endophytic community in leaves and twigs of the olive-tree (Olea europaea L.) was studied in Sicily (Italy). Two sampling areas were selected: one in San Cipirello (PA) and the other one in Racalmuto (AG). The olive-yards were similar for plant age, cultivar and agricultural management. Isolation assays were made from samples collected from each locality in spring, summer and autumn during 2007 and 2008. Quantities of fungal and bacterial isolates were different in relation to the sampled sites. The prevailing fungal genera in almost all samplings were Alternaria, Cladosporium, Diplodia, Phoma, Septoria, Stemphylium and its teleomorph Pleospora. Regarding bacterial ge…

Industrial application of selected lactic acid bacteria isolated from local semolinas for typical sourdough bread production

Abstract Four obligate heterofermentative lactic acid bacteria (LAB) strains (Weissella cibaria PON10030 and PON10032 and Leuconostoc citreum PON 10079 and PON10080) were tested as single strain starters, mono-species dual strain starters, and multiple strain starter for the preparation and propagation of sourdoughs for the production of a typical bread at industrial level. The kinetics of pH and TTA during the daily sourdough refreshments indicated a correct acidification process for all trials. The concentration of lactic and acetic acid increased consistently during fermentation. The resulting molar ratios between these two organic acids in the experimental trials were lower than those o…

Metabolomic by 1H NMR Spectroscopy Differentiates “Fiano Di Avellino” White Wines Obtained with Different Yeast Strains

We employed (1)H NMR spectroscopy to examine the molecular profile of a white "Fiano di Avellino" wine obtained through fermentation by either a commercial or a selected autochthonous Saccharomyces cerevisiae yeast starter. The latter was isolated from the same grape variety used in the wine-making process in order to strengthen the relationship between wine molecular quality and its geographical origin. (1)H NMR spectra, where water and ethanol signals were suppressed by a presaturated T1-edited NMR pulse sequence, allowed for definition of the metabolic content of the two differently treated wines. Elaboration of NMR spectral data by multivariate statistical analyses showed that the two d…

Monitoring of wheat lactic acid bacteria from the field until the first step of dough fermentation.

The present work was carried out to retrieve the origin of lactic acid bacteria (LAB) in sourdough. To this purpose, wheat LAB were monitored from ear harvest until the first step of fermentation for sourdough development. The influence of the geographical area and variety on LAB species/strain composition was also determined. The ears of four Triticum durum varieties (Duilio, Iride, Saragolla and Simeto) were collected from several fields located within the Palermo province (Sicily, Italy) and microbiologically investigated. In order to trace the transfer of LAB during the consecutive steps of manipulation, ears were transformed aseptically and, after threshing, milling and fermentation, s…

Effects of indole-3-acetic acid on Sinorhizobium meliloti survival and on symbiotic nitrogen fixation and stem dry weight production

We evaluated the effects of the main auxin phytohormone, indole-3-acetic acid (IAA), on the central metabolism of Sinorhizobium meliloti strain 1021. We either treated the Sinorhizobium meliloti 1021 strain with 0.5 mM IAA (1021+) or use a derivative, RD64, of the same strain harbouring a pathway for IAA biosynthesis converting tryptophan into IAA via indoleacetamide. We assayed the activity of key enzymes in the major energy-yielding pathways (Entner-Doudoroff, Embden-Meyerhof-Parnas, pentose phosphate, glyoxylate bypass and tricarboxylic acid cycle). We found that activity of two main regulative tricarboxylic acid (TCA) cycle enzymes was increased. Citrate synthase (CS) activity, as compa…

Yeasts vectored by migratory birds collected in the Mediterranean island of Ustica and description of Phaffomyces usticensis f.a. sp. nov., a new species related to the cactus ecoclade

Nine yeast species belonging to genera Candida , Cryptococcus , Phaffomyces , Rhodotorula and Wickerhamomyces , and one species of Aureobasidium genus were isolated from the cloaca of migratory birds. Candida glabrata and C. inconspicua were the species most frequently isolated and Wickerhamomyces sylviae , which has recently been described as a new species isolated from bird cloaca, was again found. The majority of isolates showed the ability to grow up to 40 °C and/or at pH 3.0, two environmental conditions typical of the digestive tract of birds. The phylogenetic analysis of the D1/D2 domain of 26S rRNA gene placed the cultures of Phaffomyces in a new lineage that differed from the close…

Presence and characterisation of verotoxin producing E. coli in fresh Italian pork sausages, and preparation and use of an antibiotic-resistant strain for challenge studies

One hundred and twenty six samples of fresh pork sausages were analysed-for the presence of verocytotoxigenic Escherichia coli (VTEC). Selective enrichment followed by DNA extraction and PCR amplification of the stx1 and stx2 genes highlighted the occurrence of the above mentioned genes in 20 out of 126 samples screened. From the stx positive enriched cultures, isolation was performed on CT-SMAC agar plates after immuno-magnetic separation of E. coli O157. Fifty three non-sorbitol fermenting isolates were obtained and further characterised, along with the reference strain E. coli ATCC 35150(T). All the isolates were characterised by PCR assays, assessing the presence of stx1, stx2, rfbE(O15…

Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Industrial Scale Level

Red grape Nero d’Avola cultivar grape pomace powder (GPP) was applied during fresh ovine cheese production in order to increase polyphenol content. Before cheeses were produced, the bacteria of a freeze-dried commercial starter culture were isolated and tested in vitro against GPP. Two dominant strains, both resistant to GPP, were identified. Thestarter culture was inoculated in pasteurized ewe’s milk and the curd was divided into two bulks, one added with 1% (w/w) GPP and another one GPP-free. GPP did not influence the starter culture development, since lactic acid bacteria (LAB) counts were 109 CFU/g in both cheeses at 30 d. To exclude the interference of indigenous LAB, the pasteurized m…

Use of transglutaminase to reticolate protein componente of hydrocolloid mulching films: preparation, characterization and biodegradability properties

Antagonistic activity of Bacillus subtilis strain AG1 against fungal microorganisms associated with Vitis vinifera.

Fennel waste-based films suitable for protecting cultivations.

Biodegradable, flexible, and moisture-resistant films were obtained by recycling fennel waste and adding to fennel homogenates the bean protein phaseolin that was modified or not modified by the enzyme transglutaminase. All films were analyzed for their morphology, mechanical properties, water vapor permeability, and susceptibility to biodegradation under soil-like conditions. Our experiments showed that transglutaminase treatment of the phaseolin-containing fennel waste homogenates allowed us to obtain films comparable in their mechanical properties and water vapor permeability to the commercial films Ecoflex and Mater-Bi. Furthermore, biodegradability tests demonstrated that the presence …

An integrated technological approach to the selection of lactic acid bacteria of flour origin for sourdough production

article i nfo Several lactic acid bacteria (LAB) were evaluated in situ for their potential in sourdough fermentation. The strains belonged to Lactobacillus plantarum, Lactobacillus sakei, Lactobacillus sanfranciscensis, Leuconostoc citreum, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides and Weissella cibaria. LAB were used, in individual inocula, to carry out the fermentation of γ-ray treated (sterile) flour and untreated commercial flour, in order to evaluate their performances both in the absence and presence of the native microbiota of flour. The pH and total titratable acidity (TTA) showed a strong and fast acidification of the experimental sourdough determined by W. cibari…

Microbiological Characteristics of Wild Edible Mushrooms and Effect of Temperature during Storage of Morchella conica

Background: The continuous worldwide increase of consumption of fresh mushrooms has registered in the recent years. The major goal of this study was to determine the microbiological characteristics of wild edible mushrooms and effect of temperature during storage of Morchella conica.
 Methods: Wild mushrooms of the species Boletus edulis, Cantharellus cibarius, and Leccinum aurantiacum were collected in a mixed forest of Picea abies, Betula pendula, and Pinus sylvestris located in Tartu territory, Estonia. Faecal indicators, potential pathogens, spoilage bacteria, and microfungi (yeasts and moulds) were evaluated. M. conica was microbiologically investigated for 24 days under different…

Detection of endophytic bacteria in leaves of Vitis vinifera by using fluorescent in situ hybridization (FISH.

Characterization of kefir-like beverages produced from vegetable juices

The aim of this work was to develop new non-dairy fermented beverages using vegetable juices as fermentable substrates. Carrot, fennel, melon, onion, tomato and strawberry juices underwent back-slopping fermentations, carried out by water kefir microorganisms. Results indicated that lactic acid bacteria and yeasts were capable of growing in the juices tested. Melon juice registered the highest numbers of microorganisms. Almost all juices underwent a lactic fermentation. After fermentation, there was observance of a decrease of the soluble solid content and an increase of the number of volatile organic compounds. In particular, esters were present in high amounts after the fermentation, espe…

Attitudini tecnologiche di batteri lattici starter per la fermentazione di olive verdi da mensa

The main characteristics for lactic acid bacteria to be used as starter cultures for table olive production include the capacity to grow in presence of high concentrations of sodium chloride (NaCl) and phenols and at low temperatures. These bacteria have to show a homolactic fermentation for carbohydrates and the ability for a rapid acidification of brines. Other important traits for strain selection are represented by the expression of β-glucosidase enzymes, antimicrobial substances and flavoring metabolites. Lactobacillus plantarum and Lactobacillus pentosus are frequently employed as starter for table olives. Recently, lactobacilli/enterococci mixed starter cultures have been used for th…

Heterotrophic microorganisms in deteriorated medieval wall paintings in southern Italian churches

The Campania region in southern Italy is noted for its large number of churches that harbour invaluable frescoes, dated from the beginnings of the 4th up to the 13th century. The wall paintings represent an integral part of the monuments, and their deterioration constitutes a potentially significant loss for the world's cultural heritage. Heterotrophic microorganisms such as bacteria and mould can grow on the surface of paintings that contain a wide range of organic and inorganic constituents, and provide different ecological. niches that are exploited by a large variety of microbial. species. We isolated and identified the heterotrophic microorganisms found in the biodegraded medieval wall…

Le comunità blastomicetiche del vitigno autoctono Rovello bianco (Campania) e loro utilizzo in vinificazioni commerciali

Evolution of microbiological and chemical parameters during red wine making with extended post-fermentation maceration.

Abstract The aim of the present work was to investigate the microbiological, chemical, and sensory characteristics of red wine subjected to post-fermentation maceration that was extended to 90 days. For this purpose, the ‘Aglianico di Taurasi’ grape was used as a case study. The total yeast concentration increased until day 40 of maceration and decreased thereafter, whereas the concentration of lactic acid bacteria slightly increased. Dekkera/Brettanomyces spp. and acetic acid bacteria were not detected. The yeast community was composed of Saccharomyces cerevisiae, Zygosaccharomyces bisporus, Metschnikowia pulcherrima, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Pichia guilliermondi…

Persistence of a mixed lactic acid bacterial starter culture during lysine fortification of sourdough breads by addition of pistachio powder

Abstract Pistachio powder was added to flour or semolina to evaluate its contribution to increase the amount of lysine in bread. Bread production was carried out by sourdough technology using a selected 3-species (Lactobacillus sanfranciscensis/Leuconostoc citreum/Weissella cibaria) lactic acid bacterial (LAB) starter culture. All sourdoughs were subjected to a long-time fermentation (21 h) and showed levels of LAB around 109 CFU/g, indicating the suitability of pistachio powder for lactic fermentation. Yeasts were also detected, in particular in semolina trials. MiSeq Illumina technology was applied to investigate the bacterial composition of sourdoughs evidencing a different distribution …

Spoilage potential of Brettanomyces bruxellensis strains isolated from Italian wines

Abstract Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B. bruxellensis population investigated. All strains were evaluated for the…

Biotyping of Saccharomyces cerevisiae strains isolated from “Moscato of Saracena”, a southern Italy passito-wine (Calabria Region).

Influence of indigenous Hanseniaspora uvarum and Saccharomyces cerevisiae from sugar-rich substrates on the aromatic composition of loquat beer

The demand for unique and exclusive food products and beverages is constantly on the increase. One of the products that mostly evolved to encounter market dynamics in the last decade is craft beer. For a long time, craft breweries have included fruit in beer production to enrich flavour and aroma profile of different beer styles. In this study, for the first time, the use of Saccharomyces and non-Saccharomyces yeast strains isolated from high -sugar matrices (manna and fermented honey by-products) were investigated to diversify fruit craft beer pro-duction, in order to improve the fermentation process and highlight the complexity of aroma profiles generated during alcoholic fermentation. Tw…

Improving the Aromatic Profiles of Catarratto Wines: Impact of Metschnikowia pulcherrima and Glutathione-Rich Inactivated Yeasts

Catarratto is one of the most widely cultivated grape varieties in Sicily. It is an indigenous non-aromatic white grape variety. Despite its widespread use in winemaking, knowledge of the aroma and chemical and microbiological properties of Catarratto wines is quite limited. The influence of Metschnikowia pulcherrima combined with Saccharomyces cerevisiae on the aromatic expression of Catarratto wines was investigated with and without the addition of glutathione-rich inactivated yeast. The substance is a natural specific inactivated yeast with a guaranteed glutathione level used to limit oxidative processes. The aromatic profiles of the final wines were determined through analysis of the vo…

Migration patterns and fat reserves of Curlew Sandpipers Calidris ferruginea at a stopover site in southern Italy

The Volturno Plain, southern Italian coast, is a regular stopover site for Curlew Sandpipers during northward migration. During 1992–1998, 2,177 Curlew Sandpipers were ringed and measured on northward migration; numbers trapped each year fluctuated. Peak passage was during the period 6–10 May, with 94% of birds trapped in the period 1–20 May. Median date of passage of males preceded females by about five days. Using a new visual method to evaluate fat deposition in waders, there was a strong correlation between body weight and visually estimated fat deposits. Birds showed a mass increase of 2.8 g/day. The mean stopover duration was 2.2 days. Only 0.9% of the total catch of Curlew Sandpipers…

Animal rennets as sources of dairy lactic acid bacteria

ABSTRACT The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri , were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH …

Influence of salt of different origin on the microbiological characteristics, histamine generation and volatile profile of salted anchovies (Engraulis encrasicolus L.)

Abstract The effect of six salts of different geographical areas on the quality of salted anchovies was evaluated. The crude salts were chemically characterized by determination of inorganic and volatile organic compounds (VOCs). Salted anchovies, corresponding to six experimental trials, were subjected to microbiological, chemical (including histamine content) and sensory analysis during the entire period of ripening (150 days). The salts were characterized by marked differences in terms of major cations and trace element amounts. Among the 27 VOCs detected, octadecane was the most abundant compound and the main differences of the salts were registered for alkanes and alcohols. During matu…

Effect of iron-porphyrin treatment on soil microbial communities

Intensive agricultural management have led to an increasing transfer of carbon from soil organic matter (SOM) to atmospheric CO2. It is noteworthy that the flux of CO2 from the soil is ten times greater than fossil fuel emission from industrial and automotive activities. Piccolo and co-workers (1999) suggested that hydrophobic humic components in soil exerted hydrophobic protection towards easily degradable compounds. They postulated that associations of apolar molecules deriving from plant degradation and microbial activity incorporate more polar molecules, thus preventing their otherwise rapid microbial degradation and enhancing their persistence in soil. Moreover, synthetic metal-porphyr…

Preliminary Evaluation of the Influence of Traditional Dairy Plant Equipment on the Microbiological Quality of “Caciocavallo Palermitano” Cheese

Caciocavallo Palermitano” is a raw cows’ milk cheese produced within Palermo province (Sicily), processed according to “pasta-filata” cheese technology without starter addition. Production flow-sheet includes a 15-minute milk bulk resting in “tina”, the traditional wooden vat used for cheese-making. This study was aimed to evaluate the influence of traditional equipment on the characteristics of cheese; at this stage, it was forwarded to the characterization of the microbiological populations of “Caciocavallo Palermitano” during each step of manufacturing. Two milk bulks (A and B), from different farming systems, were compared before and after resting in tina. After delivery at dairy factor…

Potential exploitation of lysozyme in the winemaking of Sicilian wines from ???organic grapes"

Lysozyme is a natural enzyme with muramidase activity which can work against a range of lactic acid bacteria (LAB), including Oenococcus, Pediococcus and Lactobacillus spp., that can affect wine stability (Cunningham et al., 1991). For such reason, over the last decade, there has been a growing interest in lysozyme as a supplement to sulphur dioxide for bacterial inhibition (Sonni et al., 2009). Since, lysozyme applications proved to be enough specific to require technical knowledge and expertise to be efficient, an experimental winemaking was performed to evaluate the efficiency of this enzyme application to produce a Sicilian wine from “organic grapes”. Specifically, two experimental cond…

The influence of addition of Borago officinalis with antibacterial activity on the sensory quality of fresh pasta

Abstract Borage (Borago officinalis L.) is a herbaceous plant of the Boraginaceae family cultivated throughout the world for several purposes, including food preparations, mainly beverages and salads. Some Italian recipes use borage as a food ingredient, in particular as condiment for pasta. The aqueous extract (AE) from borage leaves can act as biopreservative in foods due to its inhibition towards the main foodborne pathogen bacteria. Fresh pasta, due to the high content of water, is a food product with a limited shelf life. In order to test the suitability of borage to produce fresh pasta with a prolonged shelf life, borage AE was used in dried form as a raw material for the production o…

Application of Hydrogen Peroxide to Improve the Microbiological Stability of Food Ice Produced in Industrial Facilities

This work was aimed to produce an “active” food ice to preserve its microbiological safety over time. With this in mind, ice cubes were processed with the addition of H2O2 to water before freezing. Four food ice productions were performed at the industrial level: one control trial without the addition of H2O2 (0OX) and three experimental trials obtained by adding 4, 8, and 12 mg/L of H2O2 (4OX, 8OX, and 12OX), respectively. After production, all food ice trials were artificially contaminated with 102 CFU/100 mL of water-borne pathogenic bacteria (Escherichia coli ATCC 25922, Enteroccus faecalis ATCC 29212, and Pseudomonas aeruginosa ATCC 27853) inoculated individually. Thawed ice samples we…

Dissemination of oenological yeasts through bird migration in Sicily.

The composition of yeast communities on shown to be dependent on several factors, including geographical location of the vineyard, type of soil, age of the vineyard, grapevine variety and harvesting technique. Moreover, insects and birds were in part responsible for the dissemination of fermentative yeasts during their feeding (Francesca et al, 2009). In order to evaluate the dissemination of fermenting yeasts, migrating and vineyard inhabiting birds were caught and ringed in four experimental sites: “Riserva Naturale Integrale Lago Preola e Ghorghi Tondi” (Mazara del Vallo, TP) and the Sicilian islands of Lampedusa, Ustica and Linosa. The last sites represent important stop-over for migrat…

Identification of Predominant Lactic Acid Bacteria and Yeasts of Turkish Sourdoughs and Selection of Starter Cultures for Liquid Sourdough Production Using Different Flours and Dough Yields

WOS: 000375613200005

CARATTERIZZAZIONE DEL PROFILO AROMATICO E PROVE PRELIMINARI DI INIBIZIONE MICROBICA PER L’OLIO ESSENZIALE ESTRATTO DALLE BUCCE DI CITRUS RETICULATA cv. “TARDIVO DI CIACULLI”

Il mandarino denominato “Tardivo di Ciaculli” ha avuto origine e viene prodotto in provincia di Palermo (Sicilia) nei pressi della contrada Ciaculli. Ha un’epoca di maturazione tardiva che si concentra nei mesi da febbraio ad aprile. I frutti sono piccoli e con buccia di medio spessore [1]. In generale gli oli essenziali di mandarino sono particolarmente apprezzati per le loro proprietà chimico-fisiche costituendo un fondamentale ingrediente nell’industria cosmetica e alimentare come esaltatori di sapore in cibi e bevande. Inoltre trovano un impiego sempre maggiore nelle biotecnologie applicate al settore agroalimentare per ottimizzare le proprietà nutrizionali degli alimenti e prolungarne …

Le associazioni tra microrganismi

Le associazioni tra microrganismi rivestono un ruolo centrale nell’ecologia microbica, la branca della microbiologia che studia le interelazioni tra micror- ganismi, dei microrganismi con organismi eucarioti (protozoi, nematodi, piante e animali) e con le componenti abiotiche dell’ambiente. I microrgani- smi possono anche partecipare ad associazioni genetiche, quali coniugazione, trasduzione e trasformazione, in particolare i batteri sono frequentemente implicati in una serie di interazioni non genetiche con altri microrganismi oggetto di questo capitolo. Infatti, in qualsiasi habitat i microrganismi viva- no e si moltiplichino essi devono interagire con altri micro- e macrorganismi facendo…

Could halophilic archaea improve the traditional salted anchovies (Engraulis encrasicholus L.) safety and quality?

Aims:  The positive influence of two selected extremely halophilic archaea strains in the production of salted anchovies (Engraulis encrasicolus, L., 1758) was highlighted. Methods and Results:  Anchovies produced with salt artificially contaminated with halophiles exhibited lower loads of staphylococci, Enterobacteriaceae and lactic acid bacteria, and a reduced content of histamine as well as an improved organoleptic acceptance. Conclusions:  The findings of this survey are expected to enhance the safety of salted anchovies, with regard to the histamine formation during ripening, and to improve the sensory attributes of this product. Significance and Impact of the Study:  This study repres…

Introduction of a novel pathway for IAA biosynthesis to rhizobia alters vech root nodule developmt

We introduced into Rhizobium leguminosarum bv. viciae LPR1105 a new pathway for the biosynthesis of the auxin, indole-3-acetic acid (IAA), under the control of a stationary phase-activated promoter active both in free-liv- ing bacteria and bacteroids. The newly introduced genes are the iaaM gene from Pseudomonas savastanoi and the tms2 gene from Agrobacterium tumefaciens. Free-living bacteria harbouring the promoter-iaaMtms2 construct release into the growth medium 14-fold more IAA than the wild-type parental strain. This IAA overproducing R. l. viciae, the RD20 strain, elicits the development of vetch root nodules containing up to 60-fold more IAA than nodules infected by the wild-type str…

Ecologia delle popolazioni lattiche associate alle farine di frumento e studio delle attitudini tecnologiche per la produzione di impasti acidi

Il presente lavoro ha previsto inizialmente l’isolamento, la tipizzazione e l’identificazione dei batteri lattici (BL) presenti in campioni di farine utilizzate per prodotti da forno a lievitazione naturale prelevati presso diversi panifici siciliani. Le conte in piastra dei BL sono state ottenute su tre differenti terreni colturali, generici e specifici. I risultati hanno evidenziato una concentrazione massima di BL di 4.75 Log UFC/g. Tutte le colonie diverse sono state isolate e purificate. Le colture sono state differenziate sulla base delle caratteristiche fenotipiche e dei profili generati mediante la tecnica randomly amplified polymorphic DNA (RAPD)-PCR che ha permesso il riconoscimen…

An innovative method to produce green table olives based on "pied de cuve" technology

The technology of “pied de cuve” (PdC) is applied in food process only to produce wines with an enriched community of pro-technological yeasts. PdC promotes the growth of the desirable microbial strains in a small volume of grape must acting as a starter inoculums for higher volumes. The aim of the present work was to investigate the use of partially fermented brines, a technology known as PdC, developed with lactic acid bacteria (LAB) on the microbiological, chemical and sensory characteristics of green fermented table olives during two consecutive campaigns. The experimental plan included two trials based on different PdCs: trial A, PdC obtained with Lactobacillus pentosus OM13; trial B, …

Microbial dynamics during green Sicilian table olive fermentations

The production of green table olives is traditionally a spontaneous fermentation carried out by indigenous microflora. Variability of microbial raw material may result in changes in the qualitative aspects of final products (Silvestri et al., 2009). Table olives of five different green table olive cultivars (four Sicilian Brandofino, Castriciana, Nocellara del Belice and Passalunara and the Spanish Manzanilla) were produced according to a semi-industrial technology, in which lactic acid bacteria (LAB) role is partially replaced by lactic acid addiction. Transformation processes were studied by a combined strategy consisting of chemical, microbiological and sensory analyses. Yeasts harboured…

Effect of the lemon essential oils on the safety and sensory quality of salted sardines (Sardina pilchardus Walbaum 1792)

The main aim of this research was to investigate the biopreservative effects of lemon essential oil (EO) micro-emulsions on salted sardines. The experimental design included two experimental trials, SR1 and SR2 carried out with 25 ml of lemon EO micro-emulsion at 0.3 and 1.0% (v/v), respectively, and a control trial performed without EO addition. Chemical analyses on salted sardines inoculated with the EOs clearly showed a substantial persistence of several volatile organic compounds (VOCs) belonging to groups of monoterpene hydrocarbons, oxygenated monoterpenes and sesquiterpene hydrocarbons derived from EOs during the entire period of ripening. In particular, the molecules mostly represen…

A survey of the main technology, biochemical and microbiological features influencing the concentration of biogenic amines of twenty Apulian and Sicilian (Southern Italy) cheeses

Abstract Twenty Apulian and Sicilian cheeses were analysed for their concentrations of eight biogenic amines (BAs), free amino acids, pH, water activity, and subjected to microbiological characterisation. In addition, lactic acid bacteria isolated from cheeses were assayed for their capacity to generate BAs. Principal component analysis was performed to find the effect of different parameters on the distribution of the cheeses. Although short-ripened (≤30 d) cheeses did not show significant BA concentrations, the only BA showing high positive correlation with time of ripening was histamine. Concentration of histidine and, especially, percentage of histidine-decarboxylase bacteria presumably…

Dissemination of wine-related yeasts by migratory birds

Summary The present work was undertaken to evaluate the contribution of migratory birds in the environmental dissemination of yeasts. Four sites (Mazara del Vallo, Lampedusa, Ustica and Linosa), representing the main stop-over points in Sicily, were analysed during spring and autumnal bird migration and 349 birds (belonging to 10 families) were ringed and analysed for yeast presence. A total of 125 yeasts were isolated and identified by a multiple genotypic approach, consisting of restriction fragment length polymorphism (RFLP) of 5.8S rRNA gene and 26S rRNA and sequencing of D1/D2 domain of the 26S rRNA gene, which resulted in the recognition of 18 species, including the technological rele…

Ecology and technological capability of lactic acid bacteria associated with Grillo grapevine used as base wine for Marsala production.

Lactic acid bacteria (LAB) have a defining role in winemaking process since their activities determine an important contribute to wine quality. Besides sulphur dioxide, lysozyme is becoming a common supplement in wine for bacterial growth inhibition (Sonni et al, 2009). It is a natural enzyme with muramidase activity working against a wide range of LAB, including Oenococcus spp., Pediococcus spp., Lactococcus spp. and Lactobacillus spp. (Cunningham et al, 1991). To obtain a first mapping of LAB inhabiting Marsala wine production area, grapes of “Grillo” variety were harvested from five vineyards different for climatic and agronomic parameters. A Marsala base wine large-scale process was fol…

Use of sequentially inoculation of Saccharomyces cerevisiae and Hanseniaspora uvarum strains isolated from honey by-products to improve and stabilize the quality of mead produced in Sicily

Mead is a beverage produced by alcoholic fermentation of honey-must. The starter yeasts that are commonly used for the alcoholic fermentation of honey-must are oenological Saccharomyces cerevisiae strains. The objective of the present work was, for the first time, to apply yeasts of honey by-products origin to evaluate the influences the taste-olfactory attributes of mead. For this purpose, three experimental productions were set up, which included: (i) single inoculation of S. cerevisiae; (ii) single inoculation of Hanseniaspora uvarum; (iii) sequential inoculation of H. uvarum/S. cerevisiae. Two control trials were performed, using a commercial strain of S. cerevisiae of oenological origi…

Transfer, composition and technological characterization of the lactic acid bacterial populations of the wooden vats used to produce traditional stretched cheeses

The biofilms of 12 wooden vats used for the production of the traditional stretched cheeses Caciocavallo Palermitano and PDO Vastedda della valle del Belìce were investigated. Salmonella spp. and Listeria monocytogenes were never detected. Total coliforms were at low numbers with Escherichia coli found only in three vats. Coagulase-positive staphylococci (CPS) were below the enumeration limit, whereas lactic acid bacteria (LAB) dominated the surfaces of all vats. In general, the dominance was showed by coccus LAB. Enterococci were estimated at high numbers, but usually between 1 and 2 Log cycles lower than other LAB. LAB populations were investigated at species and strain level and for thei…

Functional bread supplemented with Pleurotus eryngii powder: A potential new food for human health

The purpose of this study was to develop functional breads with powdered Pleurotus eryngii. The breads were produced applying the traditional Italian style sourdough technology. P. eryngii powder was added to flour of tender wheat varieties (Grano Dei Miracoli, Inalettabile, Mentana, Gentilrosso, Ardito and a mix of Rieti, Verna, and Mentana) or semolina of durum wheat landrace (Saragolla) and subjected to sourdough fermentation. Sourdough inoculum was produced with selected strains of lactic acid bacteria (LAB) belonging to the species Levilactobacillus brevis, Weissella cibaria and Leuconostoc citreum. The addition of Pleurotus powdered (PP) (10% w/w) did not influence the fermentation pr…

Non-conventional yeasts from fermented honey by-products: Focus on Hanseniaspora uvarum strains for craft beer production

The increasing interest in novel beer productions focused on non-Saccharomyces yeasts in order to pursue their potential in generating groundbreaking sensory profiles. Traditional fermented beverages represent an important source of yeast strains which could express interesting features during brewing. A total of 404 yeasts were isolated from fermented honey by-products and identified as Saccharomyces cerevisiae, Wickerhamomyces anomalus, Zygosaccharomyces bailii, Zygosaccharomyces rouxii and Hanseniaspora uvarum. Five H. uvarum strains were screened for their brewing capability. Interestingly, Hanseniaspora uvarum strains showed growth in presence of ethanol and hop and a more rapid growth…

Archebatteri alofili estremi: ruolo potenziale nella trasformazione di prodotti ittici sotto sale.

Performances of Different Metabolic Lactobacillus Groups During the Fermentation of Pizza Doughs Processed from Semolina

The main hypothesis of this work is that facultative and obligate heterofermentative Lactobacillus species can differently impact the final characteristics of pizza. The objective was to evaluate separately the behaviors of the obligate heterofermentative species (OHS), such as Lactobacillus sanfranciscensis, Lactobacillus brevis, and Lactobacillus rossiae, and the facultative heterofermentative species (FHS), including Lactobacillus plantarum, and Lactobacillus curvatus, in the sourdoughs to be used for pizza production. The production of the experimental pizzas was carried out with semolina (Triticum turgidum L. ssp. durum). The acidification process—which was followed by pH, total titrat…

Isolation and characterization of wild “terroiristes” yeasts to be used in southern Italy wine fermentation

Isolamento e caratterizzazione di lieviti autoctoni per la valorizzazione di vini tipici campani.

Evoluzione della popolazione blastomicetica durante la produzione di olive da tavola di differenti cultivar siciliane monitorata attraverso l’analisi dell’ITS rDNA.

La popolazione blastomicetica di olive verdi da tavola, prodotte a partire da 4 diverse cultivar siciliane (Brandofino, Castriciana, Nocellara del Belice, Passulunara) e da una spagnola (Manzanilla), è stata monitorata durante l’intero processo di fermentazione. La tecnologia produttiva poteva definirsi di tipo semi-industriale, giacché il ruolo della microflora lattica era parzialmente sostituito dall’aggiunta di acido lattico e la fermentazione naturale avveniva in salamoia all’8% di NaCl. La popolazione di lieviti all’avvio del processo fermentativo è risultata, indipendentemente dalla cultivar di appartenenza, nell’ordine di 2.0 log UFC g-1. Viceversa nel prodotto al consumo le conte ha…

Diversity of Saccharomyces cerevisiae strains associated to racemes of Grillo grape variety

ABSTRACT The most important oenological characteristics of high-quality sparkling wines are high content of acidity and low pH. Racemes are late-maturing grapes of Grillo variety characterized by low pH and high content of tartaric and malic acids and, due to their intrinsic characteristics, might represent an interesting technological solution to increase acid quality of base sparkling wine. To this purpose, the use of yeasts able to ferment grape must at very low pH is mandatory for the success of the process. In this work, 261 Saccharomyces cerevisiae isolated from spontaneous vinifications of Grillo grape racemes were subject to intraspecific characterization by interdelta analysis whic…

Optimised method for the analysis of phenolic compounds from caper (Capparis spinosa L.) berries and monitoring of their changes during fermentation

In this work, an ad hoc method to identify and quantify polyphenols from caper berries was developed on high-performance liquid chromatography/electrospray ionisation source/mass spectrometry (HPLC-ESI-MS). The method was applied during fermentation carried out with Lactobacillus pentosus OM13 (Trial S) and without starter (Trial C). A total of five polyphenols were identified. All samples contained high concentrations of rutin. Epicatechin was found in untreated fruits, on the contrary quercetin was detected during fermentation. Trial S was characterised by a more rapid acidification and lower levels of spoilage microorganisms than Trial C. L. pentosus dominated among the microbial communi…

Antimycotic activity of Bacillus amyloliquefaciens against fungi of vineyards soil origin

Preliminary investigations on grapevines (cv Catarratto) with symptoms of “esca” allowed the isolation of different bacterial colonies (Alfonzo et al, 2009). A Gram-positive, spore forming isolate, able to inhibit fungal growth, was subjected to identification. On the basis of the whole 16S rRNA gene sequence, it showed a similarity of 99% with Bacillus amyloliquefaciens. There are numerous reports on the antagonistic activity of this species towards several phytopathogenic microorganisms. For this reason, the potential of the bacterial strain against the fungi commonly associated to the soil of vineyards (Alternaria alternata, Aspergillus ochraceus, Aspergillus carbonarius, Cladosporium cl…

Biodiversity of Sourdough Lactic Acid Bacteria.

Modern technology of baked goods largely uses sourdoughs because of the many advantages offered over baker’s yeast. Sourdough is characterized by a complex microbial ecosystem, mainly represented by lactic acid bacteria (LAB) and yeasts, whose fermentation confers to the resulting product its characteristic features such as palatability and high sensory quality. Raw materials used in baking are not heat-treated; thus, they bring their wild microorganisms to the production process. Investigation of the composition and evolution of microbial communities of sourdough and raw materials is relevant in order to determine the potential activities of sourdough microorganisms. LAB are the main facto…

Attività antifungina e composizione chimica di oli essenziali estratti da agrumi coltivati in Sicilia.

Risulta comprovata nell’industria agroalimentare l’efficacia di oli essenziali di agrumi quale tecnologia per esaltare la sapidità di cibi e bevande. Ad oggi, il rinnovato interesse verso gli oli essenziali deriva dalle loro proprietà antibatteriche ed antifungine, che possono trovare ampia applicazione in sistemi hurdle-technology ai fini di prolungare la shelf-life di agroprodotti, specie in cibi minimally-processed e di IV gamma. Infatti, la necessità di ricercare nuove sostanze non di sintesi con proprietà antimicrobiche deriva dai cambiamenti legislativi in campo alimentare, dalla tendenza dei consumatori ad acquistare cibi processati naturalmente e dalla crescente resistenza dei patog…

In situ polymerization of soil organic matter by oxidative biomimetic catalysis

Abstract Background Agricultural practices that enhance organic matter content in soil can play a central role in sequestering soil organic carbon (SOC) and reducing greenhouse gases emissions. Methods We used a water-soluble iron-porphyrin to catalyze directly in situ oxidative polymerization of soil organic matter in the presence of H2O2 oxidant, with the aim to enhance OC stabilization, and, consequently, reduce CO2 emissions from soil. The occurred SOC stabilization was assessed by monitoring soil aggregate stability, OC distribution in water-soluble aggregates, soil respiration, and extraction yields of humic and fulvic acids. Results Soil treatment with H2O2 and iron-porphyrin increas…

Azotofissatori liberi e oligonitrofili da suoli sottoposti a pratiche agronomiche biologiche.

Ricerca di lieviti autoctoni per migliorare il profilo aromatico delle birre artigianali

In corso d’opera un’analisi di matrici appartenenti a diverse nicchie ecologiche con l’obiettivo di individuare lieviti dalle caratteristiche tecnologiche e qualitative ottimali

Seasonal variations of antimicrobial activity and chemical composition of Citrus limon L. Burm. spp. essential oils

The interest towards the application of essential oils (EOs) is increasing due to the antimicrobial potential to be used as “natural” alternative to the chemical preservation of foods [1]. EOs are aromatic oily liquids produced as secondary metabolites in various plants exerting different biological properties, such as antibacterial, antiviral, antimycotic and insecticidal. EOs are complex mixtures of lipophilic substances and the chemical composition, thereby the biological activities, is influenced by the raw plant material (genotype, part of the plant, harvest time, geographical, ecological conditions and cultural techniques) and extraction method [2].

Could halophilic archaea improve the traditional salted anchovies (Engraulis encrasicholus L) manufacture?

Although initial interest on extremely halophilic archaea turned to their involvement in the spoilage of salted meat and fish products, studies on the occurrence of such microorganisms in food ecosystems have rarely been performed. During salted anchovies production, a traditional process used by Mediterranean fishermen to obtain a tender product with a specific pleasant aroma and taste, extremely halophilic archaea belonging to the Halobacteriaceae family are often isolated. In order to elucidate the influence of halobacteria in salting and curing of this product, an experimental manufacturing was performed according to a traditional procedure. Salt to be employed was artificially inoculat…

Preliminary Investigation of Biogenic Amines in Type I Sourdoughs Produced at Home and Bakery Level

During a survey for isolating sourdough lactic acid bacteria (LAB), 20 dough samples produced at the bakery level (BL) or home-made (HM) were collected. An enzyme-based colorimetric method revealed a total biogenic amines (BAs) concentration in the range 41.4–251.8 ppm for six (three BL and three HM) sourdoughs characterised by unpleasant odours. Eight BAs generally investigated in foods were identified and quantified from these six samples by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). Only one HM sample contained almost all analysed BAs. Tryptamine was exclusively detected in HM sourdoughs (0.71–24.1 ppm). Putrescine, tryptamine, …

Evolution of fermenting microbiota in tarhana produced under controlled technological conditions

PubMedID: 21839387 The purpose of this study was to evaluate the evolution of lactic acid bacteria (LAB) and yeasts during the fermentation of tarhana produced with some pasteurised ingredients and carried out at 30 and 40 °C. The chemical parameters were those typical for tarhana production. Coliform bacteria were not detected during fermentation, while LAB and yeasts were in the range 10 7-10 8 colony forming units (CFU) g -1. Plate counts showed an optimal development of both fermenting microbial groups and the differences in cell concentrations were not significant (P > 0.05). LAB were isolated during fermentation and grouped on the basis of phenotypic and polymorphic characteristics…

Use of Different Nutrients to Improve the Fermentation Performances of Lactiplantibacillus pentosus OM13 during the Production of Sevillian Style Green Table Olives

The aim of this study was to evaluate the fermentation performance of the commercial starter Lactiplantibacillus pentosus OM13 with four nutrients (A, B, C, and D) that differed in the following ingredients: starch, sugars, maltodextrin, inactivated yeast, inactivated yeast rich in amino acids, inactivated yeast rich in mannoproteins, and salt (NaCl). For this purpose, six different experimental productions of Nocellara del Belice table olives were carried out. During transformation, the fermentation process was monitored by measuring pH and plate counts for lactic acid bacteria (LAB), yeasts, Enterobacteriaceae, Staphylococcaceae, and Pseudodomondaceae populations. At the end of the produc…

Influence of agricultural practices on organic matter mineralization mediated by soil microbial communities

Development of new non-dairy beverages from Mediterranean fruit juices fermented with water kefir microorganisms

The aim of this work was to explore the use of several Mediterranean fruit juices as fermentable substrates to develop new non-dairy fermented beverages. Microbiological, chemical and sensory features of kefir-like beverages obtained after the fermentation of juices extracted from fruits cultivated in Sicily (southern Italy) with water kefir microorganisms were investigated. Results indicated that both lactic acid bacteria and yeasts were able to develop in the fruit juices tested, but the highest levels were registered with prickly pear fruit juice. All fruit juices underwent a lactic fermentation, since a lactic acid content was detected in the resulting kefir-like beverages. Except kiwif…

Biodiversity and dairy traits of indigenous milk lactic acid bacteria grown in presence of the main grape polyphenols

ABSTRACT The present work was developed to select lactic acid bacteria (LAB) to be used as starter cultures in functional cheese production. The indigenous milk LAB populations were isolated from fermented raw ewes’ milks (four bulks) added with 0.5 mg/mL of nine polyphenols commonly found in winery by-products. After 48 h of fermentation, all milks were characterized by an increase of LAB levels of about 3–4 Log cycles. All different colonies were purified and characterized for the main physiological and biochemical traits and then differentiated genetically at strain level and identified. Ten species belonging to the LAB genera Lactobacillus, Streptococcus, Enterococcus, Leuconostoc and L…

Hygienic characteristics of radishes grown in soil contaminated with Stenotrophomonas maltophilia

Background: Stenotrophomonas maltophilia is a plant growth-promoter. This bacterium is also implicated in human diseases. Thus, after the use of this bacterium in agriculture, the safety of the final products has to be verified. Due to the ubiquitous presence of S. maltophilia in soil, in this study a massive contamination was simulated to evaluate the growth and safety of Raphanus sativus L.. Results: Different inoculums and soil treatment conditions were tested. Soils were analysed weekly and the radishes at harvest for their microbial loads and presence/persistence of S. maltophilia LMG 6606. The concentration of the bacterium added in the different trials decreased during the first week…

Biodiversity and oenological attitude of Saccharomyces cerevisiae strains isolated in the Montalcino district: biodiversity of S. cerevisiae strains of Montalcino wines.

ABSTRACT The biodiversity of Saccharomyces cerevisiae was studied in the Montalcino area (Italy). Two wineries were involved in the study, which compared the genotypic and oenological characteristics of the S. cerevisiae strains isolated in spontaneous fermentations. After isolation yeasts were identified by 26S rRNA gene sequence analysis, and S. cerevisiae strains were characterized through interdelta sequence analysis (ISA). Oenological tests were performed in synthetic grape must by varying the magnitude of the main wine-imiting factors. The evolution of alcoholic fermentation was monitored by measuring sugar consumption and flow cytometry. The results revealed the prevalence of S. cere…

Presence of endophytic bacteria in Vitis vinifera leaves as detected by Fluorescence in situ hybridization

Fluorescence in situ hybridization (FISH) in combination with confocal laser scanning microscopy (CLSM) was applied to detect and localize bacterial colonies in leaf tissues of Vitis vinifera. Leaves were cleared to minimize the autofluorescence of plant fragments. The use of fluorescently labeled bacterial probe EUB338 on discolored grapevine leaf disks allowed the estimation of the spatial distribution of different bacterial colonies. In particular, bacterial colonies were found in veins, cells, hairs, intercellular spaces, and in cut edges of leaf disks of both non-Acremonium byssoides-colonized and A. byssoides-colonized leaves of five different cultivars. Furthermore, CLSM confirmed th…

Failed inoculation af a salt-resistant strain of Rhizobium leguminosarum bv. viciae in artificial salt soils

Evolution of Yeast population durino the manufacturing of table olives from different sicilian cultivars monitored through rDNA its analysis.

Selection of amine-oxidizing dairy lactic acid bacteria and identification of the enzyme and gene involved in the decrease of biogenic amines

ABSTRACT Accumulation of biogenic amines (BAs) in cheese and other foods is a matter of public health concern. The aim of this study was to identify the enzyme activities responsible for BA degradation in lactic acid bacteria which were previously isolated from traditional Sicilian and Apulian cheeses. The selected strains would control the concentration of BAs during cheese manufacture. First, 431 isolates not showing genes encoding the decarboxylases responsible for BA formation were selected using PCR-based methods. Ninety-four out of the 431 isolates degraded BAs (2-phenylethylamine, cadaverine, histamine, putrescine, spermine, spermidine, tyramine, or tryptamine) during cultivation on …

Valutazione dell’influenza di batteri alofili estremi nella lavorazione tradizionale di alici salate

Confronto tra tecniche di fertilizzazione in differenti ordinamenti colturali: effetti sulla microflora del suolo.

Dati preliminari sulla caratterizzazione di un mutante di Sinorhizobium meliloti 1021 Kanamicina resistente e sale sensibile.

Microbial Ecology of Retail Ready-to-Eat Escarole and Red Chicory Sold in Palermo City, Italy

Background: Ready-To-Eat (RTE) foods include any edible food that is commonly consumed raw. This study aimed at evaluation of microbial ecology of retail RTE escarole and red chicory sold in Palermo city, Italy. Methods: A total of 32 mono-varietal RTE samples, including escarole (n=16) and red chicory (n=16) samples were obtained from Palermo, Italy. Both RTE vegetables at expiry date were analyzed to quantify spoilage bacteria, pathogenic bacteria, and yeast. All different colonies were isolated and identified on the basis of phenotypic characteristics and genetic polymorphisms by random amplification of polymorphic DNA-Polymerase Chain Reaction (PCR) and further genotype by sequencing th…

Effects of irrigation treatments on the quality of table olives produced with the Greek-style process

The irrigation of olive orchards is commonly applied to produce table olives with optimal size. No data have been published on the microbiological quality of drupes from irrigated olive groves during fermentation. The trials T100 and T50 (receiving a water amount equivalent to 100 % and 50 % of the required amount, respectively) and control T0 (rainfed trial) were monitored during two consecutive years. The results showed a significant increase of equatorial diameter and flesh:pit ratio of irrigated drupes. The decrease of pH and the numbers of lactic acid bacteria (LAB) registered for the irrigated trials during the fermentation were more consistent than those displayed by control T0. Lact…

Chemical Composition and Antibacterial Potential of Artemisia arborescens L. Essential Oil

This study was undertaken to characterize the essential oil (EO) of Artemisia arborescens growing wild in Sicily. EO, extracted by steam distillation, was examined for its chemical composition and for its capability to inhibit some food-borne pathogen bacteria. A total of 43 compounds (13 monoterpene hydrocarbons, 14 oxygenated monoterpenes, 10 sesquiterpene hydrocarbons, three oxygenated sesquiterpenes and less amount of other three compounds), which account 93.73% of the total oil, were identified by gas chromatography and gas chromatography-mass spectrometry. Oxygenated monoterpenes (57.32%) constituted the main fraction, with β-thujone as the main compound (45.04%), followed by the sesq…

Biological activity of Bacillus spp. evaluated on eggs and larvae of red palm weevil Rhynchophorus ferrugineus

This study was conducted to characterize the Bacillus populations associated with dead Rhynchophorus ferrugineus, to develop a biological control for the red palm weevil. Dead adult beetles, collected throughout Sicily, were used for isolating internal and external spore forming bacteria (SFB) microbiota. The isolates, preliminarily allotted to the Bacillaceae family, were tested at 4 concentrations (103 to 106 CFU/mL) for their ability to inhibit hatching of eggs of R. ferrugineus and were used at 106 CFU/mL to monitor their insecticidal activity against 10 day-old larvae. Total amounts of SFB measured outside the skeleton and in the inners part of the beetles were 5.59-6.94 and 5.17-7.05 …

PRELIMINARY DATA ON HYDROLYTIC ACTIVITY OF LACTIC ACID BACTERIA ON ß-LACTOGLOBULIN IN MILK

β-Lactoglobulin (β-lg) is the major whey milk protein and it represents the main allergen in cow and sheep milk (1). Microbial fermentation produces some proteolytic enzymes and leads to the degradation of milk protein allergens. In this study, the results of a screening on the ability of lactic acid bacteria (LAB) isolated from typical Sicilian cheeses to reduce the β-lg are shown. This screening was carried out through an indirect competitive ELISA. The lactic acid fermentation was found to be suitable for decreasing milk immunoreactivity. Twenty three strains of cheese LAB, belonging to six genera (Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus and Streptococcus), wer…

Effect on the Antioxidant, Lipoperoxyl Radical Scavenger Capacity, Nutritional, Sensory and Microbiological Traits of an Ovine Stretched Cheese Produced with Grape Pomace Powder Addition

An innovative ovine cheese enriched with red grape pomace powder (GPP) was produced to improve the functional properties of Vastedda cheese typology. Vastedda cheese making was performed adding GPP and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190). For each strain, 40 L of pasteurized ewe’s milk was divided into two aliquots representing control and experimental trials. Control cheese (CC) production did not contain GPP, while the experimental cheese (EC) production was enriched with 1% (w/w) GPP. GPP did not slow down starter development and acid generation. Plate counts and randomly amplified polymorphic DNA (RAPD)-PCR analysis confirmed the dominance of t…

The Cereal Market and the Role of Fermentation in Cereal-Based Food Production in Africa

Cereals represent the main crop in Africa (45% of arable land) and make an important contribution to the human diet in this continent. Cereals for humans are not consumed raw. Fermentation technology is widely used in Africa to transform cereals into edible products as well as to preserve and enhance the nutritional and safety aspects of cereals. In general, in Africa, this process is not controlled and is devoid of good manufacturing practices (GMPs). Spoilage and/or pathogenic microorganisms may compromise the final quality when the fermentation is not controlled. This article focuses on the role that the fermentation process could play in creating safe food conditions in Africa. Taking i…

Wickerhamomyces sylviae f.a., sp. nov., an ascomycetous yeast species isolated from migratory birds.

In the present work, we investigated the phylogenetic position and phenotypic characteristics of eight yeast isolates collected from migratory birds on the island of Ustica, Italy. A phylogenetic analysis based on the D1/D2 region of the large-subunit rRNA gene showed that all isolates clustered as a single separate lineage within the Wickerhamomyces clade. They exhibited distinct morphological and physiological characteristics and were clearly separated from their closest relatives, Wickerhamomyces lynferdii, Wickerhamomyces anomalus and Wickerhamomyces subpelliculosus, in blastn searches. On the basis of the isolation source, physiological features and molecular strain typing carried out …

Production of the Sicilian distillate “ Spiritu re fascitrari ” from honey by-products: An interesting source of yeast diversity

The “Spiritu re fascitrari” (SRF) is a typical Sicilian distillate obtained from the by-products of traditional process of honey production. Although some alcoholic fermentation of honey based products have been described, the present research represents the first investigation on the yeast ecology and the physico-chemical characteristics of honey by-products subjected to an alcoholic fermentation followed by distillation. All samples collected during manufacturing process were analysed for the count of total, osmophilic and osmotolerant yeasts. The honeycombs and equipment surfaces showed the presence of yeasts that was 1.7 and 1.1 Log (CFU/mL), respectively. After enrichment, yeast popula…

Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking

Background and Aims: Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results: Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration th…

Evaluation of the Fermentation Dynamics of Commercial Baker’s Yeast in Presence of Pistachio Powder to Produce Lysine-Enriched Breads

The present work was carried out to evaluate the microbiological, physicochemical, and sensory characteristics of fortified pistachio breads. Pistachio powder (5% w/w) was added to flour or semolina and fermented by a commercial baker’s yeast (Saccharomyces cerevisiae). Pistachio powder did not influence the biological leavening of the doughs. The kinetics of pH and total titratable acidity (TTA) during dough fermentation showed that the leavening process occurred similarly for all trials. The concentration of yeasts increased during fermentation and reached levels of 108 CFU/g after 2 h. Pistachio powder decreased the height and softness of the final breads and increased cell density…

Activation of wooden vats with selected lactic acid bacteria for the year-round production of traditional Vastedda-like cheese

Vastedda is a pasta filata cheese made from raw ewes’ milk without the addition of starter cultures. Cheese production is carried out in wooden vats characterized by microbial biofilms hosting lactic acid bacteria (LAB) responsible for the acidification of the curds. Vastedda cheese was traditionally produced during the summer season, but it is currently produced throughout the year. In order to minimize production variability, several LAB were isolated from Vastedda PDO cheeses, characterized for their technological potential (Gaglio et al., 2014a) and selected to obtain the best strain combination for the production (Gaglio et al., 2014b). In this study, the multiple strain culture compos…

Use of selected autochthonous lactic acid bacteria for Spanish-style table olive fermentation

The present work presents a successful attempt to achieve an enhanced and more predictable fermentation process in Spanish-style green olive technology by selection and use of autochthonous starter cultures. During the first phase of this work, two Spanish-like fermentations of green table olives of cultivar (cv) “Nocellara del Belice”, coming from irrigated and not irrigated fields, were monitored, in order to highlight the best agricultural conditions for drupe production and to isolate lactic acid bacteria strains with relevant technological properties. Among 88 identified isolates, one Lactobacillus pentosus strain showed remarkable biochemical features and high acidification rate in sy…

Diversity and technological potential of lactic acid bacteria of wheat flours

Abstract Lactic acid bacteria (LAB) were analysed from wheat flours used in traditional bread making throughout Sicily (southern Italy). Plate counts, carried out in three different media commonly used to detect food and sourdough LAB, revealed a maximal LAB concentration of approximately 4.75 Log CFU g−1. Colonies representing various morphological appearances were isolated and differentiated based on phenotypic characteristics and genetic analysis by randomly amplified polymorphic DNA (RAPD)-PCR. Fifty unique strains were identified. Analysis by 16S rRNA gene sequencing grouped the strains into 11 LAB species, which belonged to six genera: Enterococcus, Lactobacillus, Lactococcus, Leucono…

Escherichia coli verocitotossici in salsiccia fresca di maiale.

Effect of different salting technologies on the chemical and microbiological characteristics of PDO Pecorino Siciliano cheese

The present work was carried out to evaluate the effect of two salting technologies [dry salting (DS) and the combined dry-brine salting (DBS)] on the chemicophysical and microbiological characteristics of PDO Pecorino Siciliano cheeses of different final weight (6 and 12 kg). Dry matter was significantly influenced by both salting process and final size. Twelve kilogram cheeses treated by DBS showed higher protein content with higher soluble nitrogen per cent than 6 kg cheeses. Salt content was in the range 3.1–4.0% on dry matter. The colour did not show significant differences for any of the factors, but 12 kg cheeses subjected to DS showed higher yellow index than the other cheeses. The …

Presence of pathogenic bacteria in ice cubes and evaluation of their survival in different systems

In this study, 60 samples of ice cubes produced at different levels (domestic, restaurant and industrial facilities), within a restricted geographical area, were investigated for their general microbiological characteristics through the analysis of populations other than enteric bacteria. Total mesophilic bacteria were in the range 1.01 × 102–9.55 × 103, 3.12 × 102–6.31 × 103and 1.30 × 102–3.99 × 103CFU/100 mL of thawed ice from domestic freezer (DF), stock boxes (SB) for self-production performed with ice machines in bars and pubs, and from sales packages (SP) of industrial productions, respectively. Some DF and SP samples were negative for the presence of total psychrotrophic…

Yeasts and moulds contaminants of food ice cubes and their survival in different drinks

Aims To evaluate the levels of unicellular and filamentous fungi in ice cubes produced at different levels and to determine their survival in alcoholic beverages and soft drinks. Methods and Results Sixty samples of ice cubes collected from home level (HL) productions, bars and pubs (BP) and industrial manufacturing plants (MP) were investigated for the presence and cell density of yeasts and moulds. Moulds were detected in almost all samples, while yeasts developed from the majority of HL and MP samples. Representative colonies of microfungi were subjected to phenotypic and genotypic characterization. The identification was carried out by restriction fragment length polymorphism (RFLP) ana…

Reuse of almond by-products: Functionalization of traditional semolina sourdough bread with almond skin

Almond production generates large amounts of by-products rich in polyphenols. In this study, almond skin was explored as a valuable food ingredient in bread making. To this purpose, almond skin was used to produce functional products modifying a traditional sourdough bread recipe. The doughs were prepared replacing semolina with powdered almond skin (PAS) at 5 and 10 % (w/w). Sourdough inoculum was started with a mix of lactic acid bacteria (LAB) and propagated in semolina until reaching pH 3.7. The pH of PAS added breads was higher than that of control (CTR) breads before and after fermentation. Plate counts showed a similar evolution of LAB and total mesophilic microorganisms, but members…

Evoluzione della microflora durante il compostaggio di sottoprodotti agro-alimentari.

Antagonism of the endophytic Bacillus subtilis strain AG1 to fungal pathogens that cause tracheomycotic deterioration of wine wood

Grapevine trunk diseases can determine considerable losses in the worldwide wine industry. Symptoms of wood diseases are dead spurs, arms, cordons and same times vine death, due to cankers in the vascular tissue (Pascoe, 2000). Recent research has also showed a recrudescence either of escadisease or decay by Verticilliumdahliae and the occurrence of new wood alterations (Botryosphaeriarhodina; Mugnai et al., 1999; Wood et al., 2005; Bonfiglioliet al., 2007). Last investigations, carried out in Sicilian vineyards on fungi associated with xilematic“esca”symptoms, revealed the occurrence of genus Bacillusin wood tissues. A spore-producer Gram-positive bacterial isolate, named AG1, was identifi…

Production, stability, gene sequencing and in situ anti-Listeria activity of mundticin KS expressed by three Enterococcus mundtii strains

Three enterococci (WFE3, WFE20 and WFE31) selected as presumptive bacteriocin producers were found to be active against Listeria monocytogenes. In this study, due to their potential industrial/food applications, the three bacterial isolates were extensively characterized. Identification was performed by means of a combined 16S rRNA gene sequencing and multiplex PCR approach, and was confirmed with the sequencing of a partial region of a protein-encoding gene, namely pheS. The three isolates belonged unequivocally to the species Enterococcus mundtii. The randomly amplified polymorphic DNA (RAPD) analysis recognized three distinct strains. The supernatants were mainly active against Listeria …

Persistence of wild Streptococcus thermophilus strains on wooden vat and during the manufacture of a traditional Caciocavallo type cheese

The present work was undertaken to evaluate the influence of the wooden dairy plant equipment on the microbiological characteristics of curd to be transformed into Caciocavallo Palermitano cheese. Traditional raw milk productions were performed concomitantly with standard cheese making trials carried out in stainless steel vat inoculated with a commercial starter. Milk from two different farms (A and B) was separately processed. The wooden vat was found to be a reservoir of lactic acid bacteria (LAB), while unwanted (spoilage and/or pathogenic) microorganisms were not hosted or were present at very low levels. All microbial groups were numerically different in bulk milks, showing higher lev…

Evolution of shelf life parameters of ready-to-eat escarole (Cichorium endivia var. latifolium) subjected to different cutting operations

Abstract The present work was carried out to investigate the microbiological and physicochemical parameters of minimally processed escarole (Cichorium endivia var. latifolium) subjected to two different transformation processes, a classic ready-to-eat process (cut leaves, CL) and a process that excluded the cutting operation (entire leaves, EL) as control trial. Both trials were monitored during the refrigerated (4 °C) storage extended until 15 d. Total mesophilic microorganisms, total psychrotrophic microorganisms and pseudomonads were detected at the highest cell densities in all samples. The genotypic characterization of the dominating microbial populations resulted in the identification…

Effetto della solarizzazione con film plastici biodegradabili sulla microflora del suolo.

Investigation of the hygienic safety of aromatic plants cultivated in soil contaminated with Listeria monocytogenes

Abstract The present work was undertaken to investigate the survival of Listeria monocytogenes ATCC 19114T in soil during the whole crop cycle of rocket (Eruca sativa Mill.) and basil (Ocimum basilicum L.), to monitor its transfer to the leaves, and to evaluate its viability at harvest. To this purpose, the soil was N–P–K fertilized and four trials, obtained with different combinations of soil treatment, listerial inoculums and seed planting, were followed for each aromatic plant. Soil was weekly investigated for total microbial counts and L. monocytogenes evolution. At the starting time, un-inoculated autoclaved soil showed a limited microbial load (103 CFU g dw−1), while un-inoculated non…

Biodiversity and dairy traits of lactic acid bacteria from foliage of aromatic plants before and after dehydration process monitored by a smart sensors system

ABSTRACT The main hypothesis of this work was to evaluate the presence of lactic acid bacteria (LAB) intrinsically resistant to plant essential oils in sage (Salvia officinalis L.) and laurel (Laurus nobilis), for future applications in functional cheese production by addition of aromatic herbs. The effect of the drying process on the viability of LAB was evaluated with three biomass densities (3, 4 and 5 kg/m2). The drying densities did not affect weight loss, but influenced the levels of LAB of sage and laurel. A total of 10 different strains of Enterococcus faecium, Enterococcus mundtii, Enterococcus raffinosus and Leuconostoc mesenteroides were identified from laurel, while sage did not…

Dinamiche microbiche durante le fermentazioni delle olive da tavola siciliane

Non-starter lactic acid bacteria used to improve cheese quality and provide health benefits

Non-starter lactic acid bacteria (NSLAB) dominate cheese microbiota during ripening. They tolerate the hostile environment well and strongly influence the biochemistry of curd maturation, contributing to the development of the final characteristics of cheese. Several NSLAB are selected on the basis of their health benefits (enhancement of intestinal probiosis, production of bioactive peptides, generation of gamma-aminobutyric acid and inactivation of antigenotoxins) and are employed in cheese-making. This review describes the ecology of NSLAB, and focuses on their application as adjunct cultures, in order to drive the ripening process and promote health advantages. The scopes of future dire…

Impact of innovative agricultural practices of carbon sequestration on soil microbial community. In: Carbon sequestration in agricultural soils: a multidisciplinary approach to innovative methods

Abstract This chapter deals with the impact on soil microbiology of innovative management techniques for enhancing carbon sequestration. Within the MESCOSAGR project, the effect of different field treatments was investigated at three experimental sites differing in pedo-climatic characteristics. Several microbiological parameters were evaluated to describe the composition of soil microbial communities involved in the carbon cycle, as well as to assess microbial biomass and activity. Results indicated that both compost and catalyst amendments to field soils under maize or wheat affected microbial dynamics and activities, though without being harmful to microbial communities.

Preliminare caratterizzazione di ceppi di Saccharomyces Cerevisiae isolati da campioni di Moscato Di Saracena (Calabria).

Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking

Background and Aims Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration thro…

Jaminaea phylloscopi sp. nov. (Microstromatales), a basidiomycetous yeast isolated from migratory birds in the Mediterranean basin.

During a survey of yeasts vectored by migratory birds in the Mediterranean basin, isolations from the cloacae of members of the order Passeriformes collected in Ustica (Italy) were performed. Based on phylogenetic analysis of the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacer ITS1-5.8S rRNA gene-ITS2 region, five yeast isolates clustered in a new lineage within the Microstromatales clade. The DNA sequences of these isolates differed from those of their closest relatives, Jaminaea angkorensis and Jaminaea lanaiensis, by 20 and 25 nt substitutions in the D1/D2 domain and 119 and 131 nt substitutions in the complete ITS region, respectively. In addition, the five isolate…

Yeasts in Birds

Wild animals, particularly birds, play a relevant role in disseminating microscopic organisms, including yeasts and filamentous fungi. The ecology of yeasts associated with birds has been studied mainly for the urban avifauna, and little is known about yeasts associated with wild birds including migratory species. Recent findings on the adaptation and persistence of yeasts in animals suggest that birds can play an important role in the ecology and distribution of yeasts.

Shelf life evaluation of fresh-cut red chicory subjected to different minimal processes

Abstract Microbiological, chemical and physical parameters of minimally processed red chicory (Cichorium intybus L.) subjected to two different transformation processes were investigated. A classic ready-to-eat (RTE) process (P1) and a production without cutting (P2) were monitored during refrigerated (4 °C) storage (15 d). Total mesophilic microorganisms, total psychrotrophic microorganisms and pseudomonads were detected at the highest cell densities in all samples. Presumptive Pseudomonas population dominated the cultivable microbial community of RTE red chicory and were characterized genetically. Twenty-two randomly amplified polymorphic DNA (RAPD) types were investigated by 16S rRNA gen…

Evaluation of microbiological and physico‐chemical parameters of retail ready‐to‐eat mono‐varietal salads

An integrated microbiological and physico-chemical approach was applied to evaluate the decay of mono-varietal ready-to-eat escarole (Cichorium endivia var. latifolium) and red chicory (Cichorium intybus L. var. foliosum Hegi) during refrigeration. Total mesophilic microorganisms, including pseudomonads, and total psychrotrophic microorganisms were detected at high numbers in all samples just after packaging and at the expiry date. The dominant microbial populations analyzed by classical culture-dependent methods belonged to Pseudomonas and yeasts. Illumina sequencing identified Janthinobacterium lividum and Pseudomonas veronii as main species. Regarding the physico-chemical quality between…

Indagini preliminari su bacilli sporigeni associati ad adulti di Punteruolo rosso e loro possibili impieghi in lotta biologica.

E’ stata condotta un’indagine per isolare batteri sporigeni associati ad adulti morti di Rhynchophorus ferrugineus. La carica microbica riscontrata, sia quella superficiale che endogena, risulta essere elevata (107 UFC/gr). Gli isolati sono riconducibili al genere Bacillus. La produzione di cristalli parasporali, potenziali δ-endotossine, è stata utilizzata come parametro fondamentale per lo screening delle colture. All’attualità su un totale di 126 isolati solo 8, presentanti elevata produzione di esostrutture, sono stati sottoposti a caratterizzazione tassonomica. Gli isolati GC33 e GC76, identificati presuntivamente come Bacillus thuringiensis, sono stati saggiati alla concentrazione di …

Technological and molecular diversity of Lactobacillus plantarum strains isolated from naturally fermented sourdoughs.

Thirty Lactobacillus (L.) plantarum strains, isolated from sourdough, were identified by biochemical tests as well as 16S rDNA sequencing and differentiated on the basis of technological properties, such as amylase, protease, phytase and antirope activities. These properties were shown to be widely differing among the strains, indicating a significant technological diversity. Genetic differentiation was achieved by restriction endonuclease analysis-pulsed field gel electrophoresis (REA-PFGE) that allowed the L. plantarum strains to be divided into 10 different genomic groups. Moreover, 32 different starters were employed in dough making experiments; each starter consisted of a single strain…

Response to salinity stress of Rhizobium leguminosarum bv. viciae strains in the presence of different legume host plants

We investigated the effect of residual salts from the previous summer’s irrigation on two non-irrigated cover crops—broad bean and common vetch—and on their rhizobial symbiontics. Before sowing, seeds were inoculated with a salt-tolerant strain and a salt-sensitive strain of Rhizobium leguminosarum biovar viciae. An increase in the electrical conductivity of the saturated-soil extract from 2.0 dS m−1 to 6.0 dS m−1 caused a severe reduction of broad bean biomass, while growth of common vetch was almost unaffected by the salinity level. Our results clearly indicate that common vetch as a cover crop may increase the availability of nitrogen in soil more than broad bean also in saline environme…

Evaluation of different conditions to enhance the performances of Lactobacillus pentosus OM13 during industrial production of Spanish-style table olives.

The main objective was to set up a methodology to improve the high volume production of green table olives, cv. Nocellara del Belice. Lactobaccillus pentosus OM13 was applied during three different industrial processes of table olives as follows: trial one (IOP1) was subjected to an addition of lactic acid until a brine level of pH 7.0 was reached; trial two (IOP2) subjected to same addition of lactic acid as in trial one plus nutrient adjuvant; and trial three (IOP3) subjected to same addition of lactic acid as in trial one, but with the strain L. pentosus OM13 acclimatized in brine for 12 h before inoculation. These trials were compared against two untreated controls (spontaneously fermen…

Indigenous yeast communities in the environment of ‘‘Rovello bianco’’ grape variety and their use in commercial white wine fermentation

The indigenous yeast communities associated with several vineyard habitats were analysed. Wild yeasts were isolated, differentiated at strain level and identified. A phylogenetic tree based on partial 26S rRNA genes was constructed. The strains were characterized and the indigenous Saccharomyces cerevisiae GR1 was then used to carry out a vinification process and compared with a commercial yeast. Wines obtained were subjected to chemical and sensory analysis. The comparison between the two products highlighted differences due to the fer- menting strains employed. The vineyard environment was found to strongly influence the composition of yeast communities, thus, confirming the theory of ‘te…

Distribuzione spaziale e temporale in campo di una popolazione naturale di Rhizobium leguminosarum bv. viciae nell’area vesuviana.

In vivo application and dynamics of lactic acid bacteria for the four-season production of Vastedda-like cheese.

article Twelve lactic acid bacteria (LAB), previously selected in vitro (Gaglio et al., 2014), were evaluated in situ for their potential to act as starter cultures for the continuous four-season production of Vastedda-like cheese, made with raw ewes' milk. The strains belonged to Lactobacillus delbrueckii, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides and Streptococcus thermophilus .L AB werefirst inoculated in multiple-strain combinations on the basis of their optimal growth temperatures in three process conditions which differed for milk treatment and medium for strain development: process 1, growth of strains in the optimal synthetic media and pasteu…

Characterization of halophilic Archea isolated from different hypersaline ecosystems

Valorisation of Dairy Wastes Through Kefir Grain Production

The main aim of this work was to investigate on kefir grains (KGs) increase using different dairy by-products. To this purpose, whey and deproteinized whey from cow, goat and sheep milk were compared to the pasteurized milk of the corresponding animal species. Each substrate was inoculated with 3% (w/v) of KGs cultivated in ultra-high temperature cow milk and evalu- ated for pH decrease, total titratable acidity increase and development of lactic acid bacteria (LAB) and yeasts released in the matrices after 24 h incubation at three different temperatures (20, 25 and 30 °C). The genotypic characterization of the dominating microbial populations resulted in the identification of two LAB belon…

Influenza di batteri alofili estremi nella lavorazione tradizionale di alici salate.

Microbiological, chemical and sensory aspects of bread supplemented with different percentages of the culinary mushroom Pleurotus eryngii in powder form

Pleurotus eryngii (DC.) Quél. powder was used in bread production. Three dough trials (0, 5 and 10% of mushroom) were obtained with commercial baker's yeast. P. eryngii powder was first tested against several yeast species; 10% P. eryngii trial was characterised by the highest pH and total titratable acidity. P. eryngii did not influence negatively the fermentation process, since all trials reached yeast levels of 10 8 CFU g −1 . Mushroom powder decreased bread height and softness, increased crust redness and crumb void fraction and cell density and, although the breads were scored diverse, the overall assessment was comparable. The final breads provided higher concentrations of thiamin, ri…

Effetti della tecnologia tradizionale di caseificazione sulle caratteristiche microbiologiche e organolettiche del Caciocavallo Palermitano

New trends in technology and identity of traditional dairy and fermented meat production processes: Preservation of typicality and hygiene

Interest in ecofood tourism is strictly related to the consumption of products associated with the geographical area visited. Local products are often requested by consumers living far from the production zones (e.g. in bistro restaurants that reproduce the atmosphere of typicality). This phenomenon, if on the one hand guaranteeing the continued popularity of certain traditional foods, highlights the inherent dangers that certain types of food pose. They could spread the risks to a much wider area that they might typically inhabit. The higher the demand for certain products, the more variations of the production processes of the traditional products there will be. This is particularly evide…

Microbiological characteristics of traditional Caciocavallo Palermitano cheese making

Study of green Sicilian Table Olive Fermentation Through Microbiological, Chemical, Hs-Spme and Sensory analyses

Antilisterial effect of citrus essential oils and their performance inedible film formulations

[EN] The antimicrobial activity of eight essential oils (EOs) extracted from the fruit peel of Citrus genotypes (orange, mandarin and lemon) was evaluated against 76 strains of Listeria monocytogenes, previously isolated from different food matrices. EOs showing the most (EO L2 and EO L8) and least (EO O3 and EO M7) effective inhibition activities were chemically characterized by gas chromatography coupled with mass spectrometry (GC/MS) to compare their composition. EO L2 and EO L8 were chosen to determine the MIC and to evaluate the cell viability of the most sensitive strains (L. monocytogenes LM35 and LM69) after 1, 2, 4 and 6 h of exposure. The effectiveness of chitosan (CH) and methylc…

The Use of Winery by-Products to Enhance the Functional Aspects of the Fresh Ovine “Primosale” Cheese

Fresh ovine “primosale” cheese was processed with the addition of grape pomace powder (GPP). Cheese making was performed using pasteurized ewes’ milk and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190) inoculated individually. For each strain the control cheese (CCP) was not added with GPP, while the experimental cheese (ECP) was enriched with 1% (w/w) GPP. GPP did not influence the starter development that reached levels of 109 CFU/g in all final cheeses. The comparison of the bacterial isolates by randomly amplified polymorphic DNA (RAPD)-PCR showed the dominance of the added strains over indigenous milk bacteria resistant to pasteurization. GPP addition red…

Survey of antibiotic resistance of Pseudomonas isolated from fresh cut red chicory (Cichorium intybus L., Asteraceae)

The present work was carried out to investigate the safety aspects of minimally processed red chicory (Cichorium intybus L., family Asteraceae) regarding the antibiotic resistance of Pseudomonas Migula, 1894 populations (Bacteria Pseudomonadaceae). The Pseudomonas strains tested for their characteristics were previously isolated from experimental monovarietal salads prepared with two different processes, a classic ready-to-eat (RTE) process and a process with entire leaves, and stored under refrigeration (4 °C) up to 15 days from production. Due to their dominance over the microbial community, Pseudomonas strains were better characterised for their undesirable features that might be exerted…

Genetic diversity of a natural population of Rhizoboim leguminosarum bv. Viciae nodulating plants of Vicia faba in the vesuvian area

Fruit quality evolution of different olive table cultivars during fermentation.

Effect of the natural winemaking process applied at industrial level on the microbiological and chemical characteristics of wine.

The composition of yeast and lactic acid bacteria (LAB) communities and the chemical evolution of the large-scale commercial vinification of Catarratto IGT Sicilia, carried out under the biological regime, was followed from grape harvest until bottling. Simultaneously to the maximum growth of yeasts, LAB counts reached high level of concentration (6-7 log CFU mL(-1)) during the first steps of the alcoholic fermentation. Yeast identification was determined applying different molecular methods. The highest species biodiversity was observed on grape and must samples taken soon after pressing. Saccharomyces cerevisiae was detected at dominant concentrations during the entire winemaking process.…

Impact of Innovative Agricultural Practices of Carbon Sequestration on Soil Microbial Community.

This chapter deals with the impact on soil microbiology of innovative management techniques for enhancing carbon sequestration. With in the MESCOSAGR project, the effect of different field treatments was investigated at three experimental sites differing in pedo-climatic characteristics. Several microbiological parameters were evaluated to describe the composition of soil microbial communities involved in the carbon cycle, as well as to assess microbial biomass and activity. Results indicated that both compost and catalyst amendments to field soils under maize or wheat affected microbial dynamics and activities, though with out being harmful to microbial communities.

Effect of the mechanical harvest of drupes on the quality characteristics of green fermented table olives

BACKGROUND Because of damage caused by mechanical harvesting, the drupes for table olive production are traditionally hand harvested. Until now, no data have been available on the microbiological and chemical features of mechanically harvested drupes during fermentation. RESULTS Drupes mechanically harvested and inoculated with Lactobacillus pentosus OM13 were characterized by the lowest concentrations of potential spoilage microorganisms. On the other hand, drupes mechanically harvested and subjected to spontaneous fermentation showed the highest concentration of Enterobacteriaceae and pseudomonads during transformation. The lowest decrease of pH (4.20) was registered for the trials inocul…

Codominance of Lactobacillus plantarum and obligate heterofermentative lactic acid bacteria during sourdough fermentation

Fifteen sourdoughs produced in western Sicily (southern Italy) were analysed by classical methods for their chemico-physical characteristics and the levels of lactic acid bacteria (LAB). pH and total titratable acidity (TTA) were mostly in the range commonly reported for similar products produced in Italy, but the fermentation quotient (FQ) of the majority of samples was above 4.0, due to the low concentration of acetic acid estimated by high performance liquid chromatography (HPLC). Specific counts of LAB showed levels higher than 10(8) CFU g(-1) for many samples. The colonies representing various morphologies were isolated and, after the differentiation based on phenotypic characteristics…

"In vitro" antagonism of a grapevine endophytic Bacillus subtilis strain towards "esca" fungi.

Preliminary investigations on grapevines (CV Catarratto) with symptoms of “esca” permitted to isolate only bacterial colonies, from black punctuations belonging to the genus Bacillus. Particularly, an isolate was Gram-positive with spore forming and, on the basis of the partial 16S rRNA sequence comparison, it showed a similarity of 99% with Bacillus subtilis subsp. subtilis. There are numerous reports on the antagonistic activity of the species towards several phytopathogenic microorganisms. For this reason the possible bacterial control against the “esca” fungi (Phaeoacre- monium aleophilum, PAL; Phaemoniella clamidospora, PCH; Fomitiporia mediterranea, FOMED), was studied. The antagonist…

Yeast ecology of vineyards within Marsala wine area (western Sicily) in two consecutive vintages and selection of autochthonous Saccharomyces cerevisiae strains.

In this work, the yeast ecology associated with the spontaneous fermentation of Grillo cultivar grapes from 10 vineyards was analyzed from grape harvest till complete consumption of must sugars. The microbiological investigation started with the plate count onto two culture media to distinguish total yeasts (TY) and presumptive Saccharomyces (PS). Yeasts were randomly isolated and identified by a combined genotypic approach consisting of restriction fragment length polymorphism (RFLP) of 5.8S rRNA gene and 26S rRNA and sequencing of D1/D2 domain of the 26S rRNA gene, which resulted in the recognition of 14 species belonging to 10 genera. The distribution of the yeasts within the vineyards s…

Influence of pasteurization temperature on flesh firmness of table olives cv. Nocellara del Belice

The application of heat treatment is especially important in maintaining the organoleptic characteristics of fermented agro-food products, which potential consumers perceive as reflecting the quality of these foodstuffs. The aim of this study was to evaluate the influence of pasteurization time and temperature on the flesh firmness of table olives cv. Nocellara del Belice, packaged in glass jars, and to study their effect on the microbial community of table olives. Four different treatments were applied, one for each of the pasteurization temperatures adopted: 65 °C, 75 °C, 85 °C and 95 °C. A control test was also carried out (test Tc, not pasteurized). Each test was repeated with treatment…

Effect of grape pomace from red cultivar 'Nero d’Avola' on the microbiological, physicochemical, phenolic profile and sensory aspects of ovine Vastedda-like stretched cheese

Abstract Aims The purpose of this study was to functionalize an ovine stretched cheese belonging to 'Vastedda' typology with red grape pomace powder (GPP) of Nero d’Avola cultivar and to characterize the microbiological, physicochemical, phenolic profile and sensory characteristics of the final cheeses. Methods and Results Before cheeses production, GPP was characterized for its microbiological profile, antibacterial activity and polyphenolic content. No colonies of bacteria and yeasts were detected in the GPP. GPP showed a large inhibition spectrum against spoilage and pathogenic bacteria. Three classes of polyphenolic compounds belonging to flavan-3-ols, flavonol and phenolic acids were i…

Response of Soil Microbial Communities to Iron-Porphyrin Catalytic Amendments.

Intensive agricultural practices strongly increase CO2 emission from soil. Synthetic metal-porphyrins were shown to significantly decreased CO2 emission from soil due to an in-situ catalysis of oxidative polymerization of soil organic matter. This research aimed to assess the effects of iron-porphyrin (POR) amendments on soil microbial communities in three arable soils under wheat and maize cropping located in Naples, Turin and Piacenza, characterized by different pedological and climatic conditions. Bulk-soil and rhizo-soil were sampled during 4 years and the microbial groups directly involved in organic matter (OM) mineralization and in key processes of the nitrogen cycle were examined. M…

Could halophilic archaea improve the traditional salted anchovies (Engraulis encrasicholus L) safety and quality?

Aims: The positive influence of two selected extremely halophilic archaea strains in the production of salted anchovies (Engraulis encrasicolus, L., 1758) was highlighted. Methods and Results: Anchovies produced with salt artificially contaminated with halophiles exhibited lower loads of staphylococci, Enterobacteriaceae and lactic acid bacteria, and a reduced content of histamine as well as an improved organoleptic acceptance. Conclusions: The findings of this survey are expected to enhance the safety of salted anchovies, with regard to the histamine formation during ripening, and to improve the sensory attributes of this product. Significance and Impact of the Study: This study represents…

Evoluzione della microflora durante il processo fermentativo “Sivigliano” di olive da tavola “Nocellara del Belice”

Una lavorazione tipo “Sivigliano” di olive della varietà “Nocellara del Belice”, provenienti da coltura in irriguo e non, è stata sottoposta a monitoraggio chimico-fisico e microbiologico periodico sino al 150° giorno di fermentazione. La tecnologia adottata su tre repliche da 500 Kg ha previsto l’aggiunta di soda a 2,2°Bè a scopo di deamarizzare le olive in bagno alcalino e sei lavaggi sequenziali allo scopo di neutralizzare l’alcalinità, al termine dei quali si è provveduto alla colmatura con salamoia concentrata a 10°Bé. Il monitoraggio del pH e della concentrazione di zuccheri riduttori ha evidenziato il buon andamento del processo fermentativo per entrambe le tesi considerate, sebbene …