Variety “Rebula” (Vitis vinifera L.) determines the terroir Goriška brda “Collio” in Slovenia

Fermenting grape juice represents one of the oldest continuously maintained anthropogenic microbial environments and supports a well-mapped microbial ecosystem. Several yeast and bacterial species dominate this ecosystem, and some of these species are part of the globally most studied and best understood individual organisms. Detailed physiological, cellular and molecular data have been generated on these individual species and have helped elucidate complex evolutionary processes such as the domestication of wine yeast strains of the species Saccharomyces cerevisiae. These data support the notion that the wine making environment represents an ecological niche of significant evolutionary relevance. Taken together, the data suggest that the wine fermentation ecosystem is an excellent model to study fundamental questions about the working of microbial ecosystems and on the impact of biotic selection pressures on microbial ecosystem functioning. Indeed, and although well mapped, the rules and molecular mechanisms that govern the interactions between microbial species within this, and other, ecosystems remain underexplored. Here we present data derived from several converging approaches, including microbiome data of spontaneous fermentations, the population dynamics of constructed consortia, the application of biotic selection pressures in directed laboratory evolution, and the physiological and molecular analysis of pairwise and higher order interactions between yeast species. The data reveal the importance of cell wall-related elements in interspecies interactions and in evolutionary adaptation and suggest that predictive modelling and biotechnological control of the wine ecosystem during fermentation are promising strategies for wine making in future.

Fast, accurate, and non-destructive analytical techniques based on hyperspectral imaging (hsi) represent effective tools for food quality evaluation. A visible change in the appearance of a fresh product often negatively impacts the perceived quality from a consumer’s point of view.

High temperatures can reduce the phenolic content of grapes, especially anthocyanins and copigments involved in colour stabilisation of red wines [1]. This could make it difficult to maintain stable colour during storage [2].

Wines made from Muscat d’Alexandria grapes exhibit a high haze risk. For this reason, they are systematically treated with bentonite, on the must and sometimes also on wine. In most oenological labora-tories and in companies (trade, cooperatives, independent winegrowers), the test that is by far the most widely used, on a worldwide scale, remains the heat test at 80°C for 30 minutes to 2 hours (and some-times up to 6 hours). The tannin test (sometimes coupled with a heat treatment) and the Bentotest are still used. In this study, we show that all these tests give much higher estimates of the haze risk than the risk assessed by a 24-48h treatment at 42°C, which represents a heat wave.

The evolution of wine quality issues is historically expressed by the passage from wine quality (what is a wine?) to wine quality (what is a good wine?). Perhaps the next question could be: what is a good sustainable wine? To contribute to reflection on this theme, it may be worthwhile to undertake an exercise in prospective fiction, which we have identified in the hypothesis of the AOD, the “appellation d’origine durable”, a scenario we will develop in the light of developments in the wine industry and the regulation on geographical indications.