0000000000351686
AUTHOR
Rosa Palmeri
Production and characterization of glicosidases from Aspergillus terreus using "pastazzo" as inductor .
Increase of trans-resveratrol in typical Sicilian wine using β-Glucosidase from various sources
β-Glucosidase (EC 3.2.1.21) (β-G) from different sources were tested to increase the trans-resveratrol in some Sicilian wines by hydrolysing resveratrol glucoside. β-G from Aspergillus niger mould was tested as a crude and purified enzyme, and compared with the same enzyme from Saccharomyces cerevisiae yeast. Specific purification served to eliminate collateral enzyme activities so that β-G could be used simply and economically. Aspergillus niger β-G produced trans-resveratrol increases of up to 75%, with no change in physico-chemical properties and bouquet, and an increase in health and nutritional properties. S. cerevisiae β-G raised free-terpenol levels, but impaired wine colour due to a…
Physicochemical properties, sugar profile, and non-starch polysaccharides characterization of old wheat malt landraces
Abstract Craft beers produced by small breweries are becoming increasingly popular worldwide due to their unique composition, taste, and flavour. Wheat malt is a traditional brewing raw material with great potential to improve beer properties such as mouthfeel, foam, haze, and flavour. In this study, the malting quality of eight wheat varieties (four common and four durum) was evaluated to explore the feasibility of producing 100 % wheat malt beer from old landraces. The physicochemical characteristics such as friability, Kolbach index, viscosity, and colour, of the wheat malts indicated a better degree of modification in the common wheat varieties when compared to that of the durum wheat v…
PARTIAL SEQUENCING OF THE BETA-GLUCOSIDASE-ENCODING GENE FROM YEAST STRAINS ISOLATED FROM MUSTS AND WINES
The aim of the present work was the identification of the gene encoding for β-glucosidase and its partial sequencing in the strainsPichia anomala AL112,Hanseniaspora uvarum Y8 andSaccharomyces cerevisiae AL41. To this aim degenerated primers, designed on the basis of aminoacid similarities of four known yeast β-glucosidases, have been used in PCR amplifications. An expected fragment of about 200 bp was amplified from all the DNAs, cloned and sequenced. Sequence homology demonstrated for the first time the presence of a β-glucosidase encoding gene inHanseniaspora uvarum andSaccharomyces cerevisiae.
DETERMINATION AND CHARACTERIZATION OF A LIPOXYGENASE FROM OPUNTIA FICUS INDICA (L.MILLER).
Dry cherry tomato: innovation from studies on isotherms
The drying of vegetables is a very ancient practice for food preservation still in use nowadays. Tomatoes cut into two parts, added with salt and dried are an important element of the food tradition in south of Italy. The tomato’s drying in Sicily is still carried out with a sun-drying process, with an empiric method. The final product obtained has a high quality which it is not homogeneous. In addition to dried products, the market offer even semidry products, to limit the loss of the nutritional characteristics of the dried product. The semidry product is a special category of dehydrated products that have a residual moisture content about 30%; for this reason, nutritional product charact…
REMOVAL OF BITTER COMPOUNDS FROM CITRUS BYPRODUCTS
Bitter compounds such as limonoids, which consist of oxygenated triterpenoid compounds, are present in citrus fruits. Removal of limonoids from citrus fruits is of considerable importance for the citrus industry. Researchers have removed limonoids from citrus fruits and citrus byproducts using organic solvents. The objective of this study was to use a simpler method to remove limonoids from citrus byproducts.
Poly(hydroxyalkanoate) synthase genes in pseudomonads strains, isolation and heterologous expression
Cherry Tomato Drying: Sun versus Convective Oven
Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content…
New application of agro-industrial waste to prevent melanosis of Mediterranean pink shrimp
Effects of thermal treatments on pectinesterase activity determined in blood oranges juices
Abstract The citrus processing industry aims to maintain turbidity and attractive colour of the juice obtained from Sicilian blood oranges. Nevertheless, the presence of pectinesterase (PE, E.C. 3.1.1.11) causes the loss of these peculiar characteristics, due to precipitation of colloids and very fine pieces of pulp in suspension, with negative effects on colour and clarification of the juices. This study compares total PE activity of Sicilian blood oranges ( Sanguinello , Moro , Tarocco ) with the blonde cultivar Navel , checking enzyme stability with various pasteurisation times and temperatures conditions. Decimal reduction time and temperature ( D and z ) as well as the kinetic constant…
Water as a Solvent of Election for Obtaining Oleuropein-Rich Extracts from Olive (Olea europaea) Leaves
Leaves from Olea europaea represent one of the main by-products of the olive oil industry, containing a plethora of bioactive compounds with several promising activities for human health. An organic solvent-free extraction method was developed for the recovery of olive leaf phenols, which obtained an extract containing oleuropein in high amounts. A comparison of various extraction media is reported, together with the total phenolic content, DPPH (2,2-Diphenyl-1-picrylhydrazyl) content, ORAC (oxygen radical absorbance capacity), and polyphenol oxidase activity of the corresponding extracts. The polyphenol profiles and content of the most representative extracts have also been studied. Extrac…
The effect of different technologies in Pomegranate jam preparation on the phenolic compounds, vitamin C and antioxidant activity
The effect of different gelling agents and processing for jam production from pomegranate juice was evaluated. In the last years, different gelling agents were tested for improving jam quality in terms of color and bioactive compounds. The unsonicated and sonicated pomegranate juices were processed for jam production by micro waves, under vacuum and cryoconcentration concentration methods using low and high methoxy pectins, and carob seed flour as gelling agents. The polyphenols content of sonicated jam was significantly lower than unsonicated samples and cryoconcentrated jams showed the significantly highest value among other methods. The results showed the highest anthocyanin content in t…
Anticancer effect of citrus limonoids: review of the available evidence.
Natural Indigo from Isatis tinctoria L. for the Reassessment of Sicilian Crops - A Minireview
OPTIMIZATION OF CITRUS PROCESS IN BLOOD ORANGE JUICE
Use of concentrated fruit juice extracts to improve the antioxidant properties in a soft drink formulation
Three juices obtained respectively from pomegranate, prickly pear and orange fruit were separately concentrated using an innovative technique, that allow to obtain a final product with high content of bioactive compounds and elevate antioxidant activity. The concentrated juices were employed in the formulation of a soft drink to improve its bioactive properties. Despite a low amount of each concentrated juice was used, the experimental soft drink obtained evidenced a high content of total polyphenols. The antioxidant activity detected was similar to that of tea commonly considered a healthy beverage with strong radical scavenging activity. The sensory analysis of the soft drink showed a con…
Employ of Citrus By-product as Fat Replacer Ingredient for Bakery Confectionery Products
Citrus fruits processing is one of the foremost industrial activities in Sicily and the main residual by-product consists in peels and seeds (known as "pastazzo"). Traditionally this by-product has been used for different purposes, and only most recently, it has been described as source of a wide range of healthy bioactive compounds and dietary fibers. In the present work, a debittered food grade orange fiber (DOF), extracted from orange juice by-product, was experimentally obtained and tested as fat-replacer at different percentages (30, 50, and 70%) in bakery confectionery products (brioches). The DOF showed high total fiber content, low water activity and a high water binding capacity. T…
Tecnologie alimentari: problemi svolti di operazioni unitarie
Le Operazioni Unitarie (OU) costituiscono gli elementi base del flow-sheet di un processo produttivo. Le OU fondamentali comuni a più processi si basano sugli stessi principi, relativi a fenomeni chimico-fisici e biologici, e quindi su tecnologie simili, anche se naturalmente le apparecchiature, i materiali di costruzione e le condizioni operative devono essere adattate. Questa scomposizione logica, permette di realizzare un qualsiasi processo mediante una sequenza ottimale di OU (Biardi G., ed. Città Studi, 2009), in cui occorre che lo studente acquisisca le medesime conoscenze e competenze. Per tale motivo le OU, vengono impartite in un insegnamento a parte, con un metodo “unitario”, che …
Use of stevia and chia seeds for the formulation of traditional and vegan artisanal ice cream
Abstract Gelato is the name of the Italian-style artisanal ice cream, a nutritious product widely consumed in different parts of the world. Due to the high content in simple sugars, ice cream should be consumed moderately by diabetic patient. This research aimed to create artisanal ice cream, using Stevia rebaudiana, a plant well known for its sweet taste and its hypoglycemic effect. Traditional and vegan ice cream were formulated using stevia and chia seeds, in order to obtain products with appreciable rheological, textural and sensorial properties. Physical and sensorial properties of the ice cream formulation containing milk protein (traditional) or vegan substitute, were evaluated. Resu…