0000000000489555
AUTHOR
R. Gaglio
Combined approach for the investigation of dominant fermenting microbiota in two traditional sourdoughs produced in sicily
In order to explore the community of lactic acid bacteria (LAB) and yeasts present in two major typical Sicilian sourdoughs, seven mature sourdoughs for "Pane Nero di Castelvetrano" (CV1 - CV3 samples) and "Pane di Monreale" (MR1 - MR4 samples) were analysed through a culturedependent and culture-independent approach. The highest values of microbial counts were revealed in MR1 sourdough. In particular, LAB counts were at about 109 CFU/g in media specific for typical sourdough LAB, such as SDB and SFM, while levels of 106 CFU/g were registered for yeasts. The total DNA form each sourdough sample was extracted and subjected to a multiplex-PCR in order to recognize the major groups of LAB. Sev…
An overview of the microbiological characteristics of the wooden shelves used in cheese ripening
Cheese ripening is a complex phenomenon affected by several factors. Among these, the influence of the wooden shelves used for aging traditional cheeses is underrated. The surfaces of the wooden boards are in contact with cheese rind for the entire ripening period and develop a microbial community. The aims of this review article is to provide an overview on the microbiological approaches applied to study the biofilms associated to the wooden tools used for dairy productions and to summarize the studies specifically performed on the wooden shelves used to ripen traditional cheeses. A critical discussion is focused on the hygienic aspects and the safety of these systems applied in cheese pro…
Development of an ad hoc starter culture for the production of functional raw ewes’ milk cheeses through the addition of grape pomace powder
The present work was carried out to select lactic acid bacteria (LAB) resistant to polyphenols in order to develop an ad hoc starter culture for the production of functional fresh ewes’ milk cheeses through the addition of grape pomace powder (GPP). To this purpose, raw ewes’ milk samples were inoculated with individual polyphenols belonging to five classes: flavanols (cathechin, epicatechin and epigallocathechin), flavonols (quercetin), flavones (rutin), hydroxyl-benzoic acid (vanillic acid and syringic acid) and hydroxyl-cinnamic acid (caffeic acid and cumaric acid). These polyphenols are commonly associated with the wine industry by-products and were added in milk to a final concentratio…
EFFECTS OF CITRUS ESSENTIAL OILS ON THE MICROBIOLOGICAL SAFETY OF PRIMO SALE CHEESE
In the last years, the consumers demanding foods with no chemical preservatives for food conservation, determined an interest by the food industries for the use of natural biopreservatives. Several essential oils from various plants and fruits have been characterized for their antibacterial activities in order to select new biopreservatives. The aim of this work was to evaluate the organoleptic effect of citrus essential oils to be applied in the processing of sheeps’ milk “Primo Sale” cheese and the inhibitory effect on the main bacterial pathogens of dairy interest. In order to better evaluate the antibacterial effect, the first approach was based on pasteurized milk, in view of the futur…
Effect of Opuntia ficus-indica Mill. mucilage edible coating on quality of fresh-cut cactus pears during cold storage
Cactus pear [(Opuntia ficus-indica (L.) Mill.] consumption and marketability are limited by the presence of spines and glochids on the fruit surface. Minimally processed cactus pear fruits are characterized by a short shelf life due to the peel removing that increases tissue senescence and deterioration. The aim of this study was to evaluate the effect of O. ficus-indica (OFI) mucilage edible coating on quality, nutraceutical, and sensorial parameters of minimally processed cactus pear. OFI fruits were collected in mid-October and were quickly moved to the nearby laboratory. One-year-old cladodes were sanitized, sliced into squares, and cooked in a microwave oven and mixed using a homogeniz…
Microorganisms of food ice cubes and their transfer to drinks
The present work was carried out to investigate the microbiological characteristics of the ice cubes produced at different levels: 1) home-made (HM) from domestic freezers; 2) produced by ice machines in bars and pubs (BP); 3) produced by ice industries (IN). BP samples were collected from the box stocks. HM and BP samples were transferred into sterile stomacher bags. IN samples were provided in the manufacturers’ plastic bags. Samples were transported into thermal insulated boxes. Five samples per each production level, forming a total of 15 samples (HM1-HM5, BP1-BP5, IN1-IN5), were collected in duplicate in two consecutive months. Each ice sample was thawed in 1 L sterile Dhuram’s bottle …
On the thermal-hydraulic performances of the DEMO divertor cassette body cooling circuit equipped with a liner
Abstract In the framework of the Work Package DIV 1 - “Divertor Cassette Design and Integration” of the EUROfusion action, a research campaign has been jointly carried out by University of Palermo and ENEA to investigate the steady-state thermal-hydraulic performances of the DEMO divertor cassette cooling system. The research activity has been focussed onto the most recent design of the Cassette Body (CB) cooling circuit, consistent with the DEMO baseline 2017 and equipped with a liner, whose main function is to protect the underlying vacuum pump CB opening from plasma radiation. The research campaign has been carried out following a theoretical-computational approach based on the finite vo…
Microbial diversity of traditional Sicilian cheeses
Traditional Sicilian cheeses are manufactured in small size farms with raw milk from animals of indigenous breeds and without the addition of starter cultures. In order to transform milk into cheese, the presence of lactic acid bacteria (LAB) is required. The main sources of desirable LAB are generally the milk, the rennet, the equipment used during processing and the dairy environment. In the last years, the microbial characterisation of traditional Sicilian cheeses, such as Caciocavallo Palermitano, Protected Designation of Origin (PDO) Pecorino Siciliano and PDO Vastedda della valle del Belìce have been the object of different studies conducted by our research group. To this purpose, the…
Il vino e la fermentazione alcolica
Il consumo di bevande alcoliche ha da sempre accompagnato la storia dell’uomo, riscontrandosi in tutte le civiltà, dalle meno evolute a quelle più progredite. Le scoperte scientifiche del XV secolo hanno messo in luce come tutti i popoli abbiano ampiamente sfruttato il fenomeno della fermentazione di cereali per produrre bevande. Lo stesso vino, inoltre, aveva assunto fin dai tempi più antichi un valore liturgico presso tutte le civiltà che si erano affacciate al Mediterraneo. Anche oggi, e in misura maggiore rispetto al passato, si fa largo uso di bevande alcoliche ottenute sia da fermentazione che da distillazione di liquidi zuccherini. Le bevande alcoliche fermentate sono caratterizzate …
I batteri lattici delle cariossidi del grano: influenza geografica, varietale e del periodo di invecchiamento
Il presente articolo riporta i dati di alcune ricerche volte a risalire all’origine dei batteri lattici degli impasti acidi. A tal proposito, i batteri lattici del frumento di quattro varietà moderne sono stati monitorati a partire dalle spighe. Le cariossidi ospitavano livelli di microrganismi inferiori rispetto a quelli rilevati sulle spighe e queste ultime livelli inferiori rispetto alle semole. La minore biodiversità lattica è stata riscontrata sulle cariossidi, mentre le semole hanno mostrato la maggiore ricchezza di specie e ceppi. Al fine di valutare la resistenza dei batteri lattici del grano durante l’invecchiamento, le cariossidi di due varietà antiche e due moderne di grani duri …
The effects of the traditional producing system on physicochemical, microbial and sensory properties of Caciocavallo Palermitano cheese
Caciocavallo Palermitano (CP) is a traditional cheese made with raw milk from cows of Sicilian local breeds fed pasture-based diets in extensive farms (EXT), processed by an artisanal technology (ART) based on wooden tools and the action of native microflora. CP is obtained also in intensive farms (INT) where milk from cows of specialized breeds fed dry diets is transformed by advanced procedures (ADV) using a stainless steel equipment and lactic acid starter cultures. This research was planned to investigate the changes in cheese properties due to production system and ripening., Milk was collected 3 times from an EXT and an INT farm and processed in ART and ADV conditions. The 12 produced…