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This article discusses opportunities and current issues of digital approaches for papyrology. It seeks to determine whether good practice is adopted throughout the development of the projects, thereby allowing use, reuse and sustainability over the long term, hence ongoing usefulness and usability, while suggesting possible improvements. I shall reflect on how the growth and evolution of digital content and tools, which rely on novel ways of representing and sharing primary sources, analysis and interpretation, with their various purposes and audiences, is assisting the papyrologist's work with new modes of research practices and of scholarly communication., Digital Classics Online, Bd. 8 (2022)

Natural antimicrobial agentsderived from herbs and plants have been used for millenia in medicine and food preservation. Indeed, essential oils (EO) and plants extracts (PE), in addition to contributing to flavour and taste, can act against food microbiota thus enhancing its stability. Moreover, recently, the consumers’ demand for naturalproducts – free of chemical preservatives - has been strongly increased. Fruit-based juices are susceptible to spoilage microorganisms,mainly yeasts and lactic acid bacteria, which negatively affect their organoleptic and nutritional properties making the product unacceptable to consumers. The aim of this study was to evaluate the effects ofnatural compounds, i.e. EO of Satureja montana and PE of Cotinus coggygria, in combination with mild thermal treatments on shelflife of carrot-orange juice and its microbial stability. In particular, viability of two spoilage microrganims Saccharomyces cerevisiae and Lactobacillus plantarumwas addressed. The EO and PE were preliminarly characterized by gascromatographic analises whichshowedthat S. montana was composed mainly by carvacrol and o-cimene, while the main components of C. coggygria were sulfuretin and fustin. Both S. montana EO and C. coggygriaPE displayed a good antimicrobial activity against S. cerevisiae, with minimum inhibitory concentration (MIC) values of 0.351 mg/ml and 0.094mg/ml, respectively. On the other hand, Lactobacillus plantarum was more resistant thanS. cerevisiae(MIC >0.5 mg/ml). The freshcarrot-orange juice was added with the S. montanaEO or C. coggygriaPE at MIC/4 concentrations for S. cerevisiae. Following its deliberatecontamination with the spoilage microrganisms (4 LogCFU/ml), samples were heat treated (60 °C for 2 or 5 min) and stored at room temperature for 9 days or 4°C for 50 days. Changes insurviving spoilage microbiota, pH, colour and antioxidant activity were monitored over storage. Overall, the results highlighted the possibility of stabilizing a juice with a high pH (5.4)by applying the "Hurdle Technology". The natural compounds enhanced the efficacy of heat treatments in inactivating/damaging the spoilage biota and delaying its recovery over storage. Moreover, no significant changes in the pH and color of the juices were found during storage, while limited variations in the antioxidant activity were detected

Food industries produce high amounts of by-products, wastes and residues which are considered a problem because they contribute to environmental pollution. On the other hand, by-products are generally rich in various nutrients and functional compounds, e.g., dietary fibres and/or bioactive components such as flavonoids and polyphenols recognized as antimicrobial and anti-radical compounds. A possible strategy for their valorization is their use as feedstock for microbial fermentation by selected strains of yeast and lactic acid bacteria (LAB) for the production of valuable bio-based compounds. In particular, in this study olive pomace (OP) and tomato residues and seeds (TR) were analyzed, and 31 strains of yeasts were isolated from OP and 30 from TR. In addition, more than 50 strains of LAB were isolated from TR. Yeasts were characterized for some metabolic features such as lipase, protease and beta-glucosidase activities. When grown in culture media with OP or TR as the only nutrient source, marked lipolytic and proteolytic activities were shown by some yeast strains already after 2 days of incubation at 30°C. Moreover, more than 60 volatile compounds interesting for the food, cosmetics or chemical sectors were detected by GC/MS-SPME analysis. In particular, several molecules used as food flavouring or perfume compounds were identified. In conclusion, the results obtained indicate that the tested biotechnological approach can be a promising strategy for the exploitation of polluting by-products through the production of bio based flavours. From a technological point of view, the yeast isolates could be also exploited for bioremediation of olive oil wastewaters or as a source of enzymes of biotechnological interest.

Eötvös Loránd University&nbsp

Because of the impossibility to consume food of animal origin, vegan consumers are looking for substitutes that could enrich their diet. Among many substitutes, fermented nut products are made from different nut types and obtained after soaking, grinding, and fermentation. Although other fermented vegetable products have been deeply investigated, there are few data about the fermentative processes of nut-based products and the microbial consortia able to colonize these products are not yet studied. This study characterized a hand-made vegan product obtained from cashew nut. Lactic acid bacteria responsible for fermentation were identified, revealing a succession of hetero- and homo-fermentative species during process. Successively, some lactic acid bacteria isolates from the home-made vegan product were used for a pilot-scale fermentation. The products obtained were characterized and showed features similar to the home-made one, although the microbiological hazards have been prevented through proper and rapid acidification, enhancing their safety features. Practical Application: Spontaneous fermented products are valuable sources of microorganisms that can be used in many food processes as starter cultures. The lactic acid bacteria isolated in this research can be exploited by industries to develop new foods and therefore to enter new markets. The use of selected starter cultures guarantees good organoleptic characteristics and food safety (no growth of pathogens).