Wine lees: characterization and valorization by kombucha fermentation

The vineyard is capable of fixing carbon in its permanent structure from atmospheric carbon dioxide, through the process of gas exchange and the performance of photosynthesis. The photosynthetic capacity of the vineyard depends on the water resources that the plant may have at its disposal, so the amount of dry matter, derived from the processed photosynthates, that it can store will depend on the water regime of the crop, both in the annually renewable organs as in permanent parts.

The separation of different grape juice press fractions is an important step in the production of sparkling base wines. A complete press cycle for this style of wine is a series of pressure increases (squeezes) resulting in variations in juice composition during the press cycle. After alcoholic fermentation, wines obtained from grape juices also exhibit strong differences for numerous characteristics. Nevertheless, there is no statistical study of the impact of the press cycle on grape juices and wine colour/composition. So, the aim of this study (vintage 2018) was to investigate the changes in composition and colour parameters of Pinot noir and Pinot meunier grapes juices, as well as their corresponding wines, during the pressing cycle.

A two years trial was carried out in Chianti (Central Italy) to assess at the detailed scale the viticultural and oenological suitability for Sangiovese of different pedoclimatic conditions, by means of the ΔC13 measured in the must sugars

Under standard champagne tasting conditions, the complex interplay between the level of dissolved CO2 found in champagne, its temperature, the glass shape, and the bubbling rate, definitely impacts champagne tasting by modifying the neuro-physico-chemical mechanisms responsible for aroma release and flavor perception. Based on theoretical principles combining heterogeneous bubble nucleation, ascending bubble dynamics and mass transfer equations, a global model is proposed (depending on various parameters of both the wine and the glass itself), which quantitatively provides the progressive losses of dissolved CO2 from laser-etched champagne glasses.

To obtain a quality wine, it is necessary to collect grapes in an optimal state of maturation, so the control of the ripening process is fundamental for the viticulturist.