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In order to examine whether olive pomace (OP), the mean by-product of olive oil extraction, can be included in the animal diet, its effect on the raw mixture and sausages made from meat from OP-fed Cinta Senese swine is tested by comparing it with a diet supplemented with high oleic sunflower oil (SO) and a control diet (C). Proximate composition, pH, color, total culturable bacteria, lactic acid bacteria (LAB), and lipid oxidation are evaluated in both the raw mixture and sausages. The aroma profile is also evaluated in sausages. Olive pomace affected the fatty acid composition of the raw mixture and strongly limited the lipid peroxidation of sausages, probably due to the synergistic action of 3,4-DHPEA and α-tocopherol. Olive pomace selectively promotes LAB growth, and protected the raw mixture and sausages from discoloration. The diet also affected the content of volatile organic compounds thus enabling OP sausages to be distinguished from other sausages. Practical Applications: The protection of foods against lipid peroxidation is a very important aspect in terms of their quality. Achieving this naturally is a high priority for consumers, as there is an increasing demand for 'low impact' and 'environment-safe' production processes. The approach proposed in the present study is aimed at meeting both these objectives. Our findings demonstrate that the inclusion of olive pomace in the swine diet effectively slowed down the lipid oxidation in the sausages. The strategy we propose also meets both economic and ecological goals. Olive pomace is the main by-product of olive oil spinneret, and its re-use in another spinneret is a cost-effective way of improving the sustainability of the production process. Three different kinds of sausages are made. The experiment is aimed at studying the effect of olive pomace (OP) in controling the progression of lipid oxidation. OP have protected sausages against cholesterol oxidation, thus limiting the production of COPs (α-hydroxycholesterol, α-epoxycholesterol, and 7-ketocholesterol). The most probable mechanism is attributable to electron or H+ donor properties of polyphenols contained in olive pomace. [ABSTRACT FROM AUTHOR]

Kombucha is a mildly sweet, slightly acidic fermented beverage, commercially available worldwide, that has attracted increasing consumers' interest due to its potential health benefits. Kombucha is commonly prepared using sugared black or green tea, but also other plant substrates are frequently utilised. Kombucha is obtained by fermentation using a symbiotic culture of bacteria and yeasts, whose composition varies depending on inoculum origin, plant substrates and environmental conditions. After fermentation, kombucha drinks are usually refrigerated at 4 °C, in order to maintain their biological and functional properties. There are no reports on the fate of microbial communities of kombucha in relation to long-term storage time and temperature. Here, for the first time, we monitored the diversity and dynamics of the microbial communities of a kombucha beverage fermented with different herbs during storage at 4 °C and at room temperature, for a period of 90 days, utilising culture-dependent and independent approaches. Moreover, cultivable yeasts and acetic acid bacteria (AAB) were isolated from the beverage, inoculated in pure culture, identified by molecular methods, and yeasts assessed for their functional properties. Total yeast counts were not affected by storage temperature and time, although their community composition changed, as Saccharomyces species significantly decreased after 45 days of storage at room temperature, completely disappearing after 90 days. On the other hand, Dekkera anomala (Brettanomyces anomalus), representing 52 % of the yeast isolates, remained viable up to 90 days at both storage temperatures, and was able to produce high levels of organic acids and exopolysaccharides. Data from DGGE (Denaturing Gradient Gel Electrophoresis) band sequencing confirmed that it was the dominant yeast species in all samples across storage. Other yeast isolates were represented by Saccharomyces and Zygosaccharomyces species. Among AAB, Gluconobacter oxydans , Novacetimonas hansenii and Komagataeibacter saccharivorans represented 46, 36 and 18 % of the isolates, whose occurrence remained unchanged across storage at 4 °C and did not vary up to 20 days of storage at room temperature. This work showed that the combination of culture-dependent and independent approaches is important for obtaining a complete picture of the distinctive core microbial community in kombucha beverages during storage, elucidating its diversity and composition, and preliminary characterizing yeast strains with putative functional activities. • The microbiota of a kombucha beverage was isolated and molecularly identified. • The community composition of yeasts and AAB was affected by storage and temperature. • Dekkera anomala was the dominant yeast species in all samples across storage. • AAB persisted across storage at 4 °C and up to 20 days of storage at room temperature. [ABSTRACT FROM AUTHOR]