Polyphenols in kombucha: impact of infusion time on extraction and investigation of their behavior during “fermentation”

Comprehensive evaluation of grape composition at winery receiving areas often requires multiple measurements to ensure representativeness, as well as the use of analytical techniques that are time-consuming and involve sample preparation.

Increasing water scarcity and unpredictable rainfall patterns necessitate efficient water management in grape production. This study proposes a novel approach for monitoring grapevine water status in a commercial vertically-shoot-positioned Vitis vinifera L. Tempranillo vineyard using non-invasive spectroscopy with a battery of different AI methods to assess vineyard water status, that could drive precise irrigation. A contactless, miniature NIR spectrometer (900-1900 nm) mounted on a moving vehicle (3 Km/h) was employed to collect spectral data from the vines’ northeast side along six dates in season 2021.

Grape canes are a non-recycled byproduct of wine industry (1-5 tons per hectare per year) containing valuable phytochemicals of medicine and agronomical interest. Resveratrol and wine polyphenols are known to exert a plethora of health-promoting effects including antioxidant capacity, cardioprotection, anticancer activity, anti-inflammatory effects, and estrogenic/antiestrogenic properties (Guerrero et al. 2009). Additionally, resveratrol is a major phytoalexin produced by plants in response to various stresses and promotes disease resistance (Chang et al. 2011). Our project aims to develop polyphenol-rich grape cane extracts to fight phytopathogenic or clinically relevant fungi. We initiate the project with the development of analytical methods to analyze resveratrol mono- and oligomers (dimers, trimers and tetramers) from grape canes and we evaluate their potential activity against clinically relevant opportunistic fungal pathogens (Houillé et al. 2014).

Nowadays, the entire viticultural and enological process is wisely thought out according to the style of wine to be produced and the local climatic conditions. Acquiring the approach of a technical management route specific for wine production remains a complex learning process for students. To enhance such learning, The Ecole d’Ingénieurs de PURPAN (PURPAN), an engineering school located in Toulouse southwest France, has recently developed Creativini, a collaborative card game in English made of 150 cards spread into 14 batches. Students in groups of 3 to 6 must design a technical production route, from plant material to bottling.

Disease resistant grapevine varieties (PIWI) are increasingly important for sustainable wine production, yet the impact of different yeasts on their wine profiles remains poorly studied. In this study, nine white interspecies varieties (i.e., caladris blanc, fleurtai, hibernal, johanniter, muscaris, sauvignon kretos, soreli, souvignier gris, and voltis) grown at the faculty of agriculture, university of Zagreb (Croatia) were vinified with three different saccharomyces cerevisiae yeasts (control strain, zymaflore x5, and zymaflore xarom).