Mapping climate and bioclimatic indices at high-resolution in vineyard regions

Pre-fermentative skin maceration is a technique used in white wine production to enhance varietal aroma, but it can increase protein concentration, leading to protein instability and haze formation [1]. To prevent protein instability, wine producers typically use fining agents such as bentonite, before wine bottling, which can negatively impact sensory characteristics and produce waste [2,3]. The aim of this study was to understand the impact of alternative techniques such as the application of polysaccharides (k-carrageenan and chitosan) on protein stability and on the wine macromolecular composition.

Fungus resistant grape varieties (FRGV or PIWI) offer many benefits such as less pesticide use or premium prices for enhanced sustainability. Still, winemakers are concerned about inferior wine quality. This study evaluates how European wine consumers assess wines made from new FRGVs in comparison to traditional V. vinifera varieties. Most of them were grown in the same vineyard. Four white (Calardis Blanc, Muscaris, Sauvignac, Cabernet Blanc) und three red (Satin Noir, Cabernet Cortis, Laurot) FRGV were compared to Riesling, Sauvignon blanc, Muskateller, Cab. Sauvignon and Merlot. For each FRGV, different styles were vinified using standardized protocols.

The postharvest dehydration of grapes is a traditional practice to obtain wines with unique traits (e.g. sweet, dry/reinforced). The modern facilities (dehydrating rooms) used for this purpose are equipped with systems for artificially controlling the inside environment parameters, to obtain the desired dehydration kinetic and preserve the grapes from grey mold (Botrytis cinerea) infection, However, the conditioning systems are extremely energy-demanding and the identification and practical applications of solutions effective in controlling/reducing the postharvest decay would reduce the costs of the operation of the dehydration facilities. To this end, we explored the potential of ozone-based treatments on harvested grapes and preliminarily tested if the treatment could impact the normal behavior and metabolism of grapes during the traditionally slow dehydration practice.

Alcoholic fermentation is the main step for winemaking, mainly performed by the yeast Saccharomyces cerevisiae. But other wine yeasts called non-Saccharomyces may contribute to alcoholic fermentation and modulate the wine aroma complexity. The recurrent problem with the use of these non-Saccharomyces yeasts is their trend to die off prematurely during alcoholic fermentation, leading to a lack of their interesting aromatic properties searched in the desired wine. This phenomenon appears to be mainly due to interactions with S. cerevisiae. These interactions are often negatives but remain unclear because of the species and strain specific response. Among the non-Saccharomyces yeasts, Lachancea thermotolerans is a wine yeast naturally found in grape must and well known as a great L-lactic acid producer and an aromatic molecules enhancer, but its behavior during alcoholic fermentation can be completely different in co-fermentation with S. cerevisiae in function of strain used.

Kombucha is a non-alcoholic beverage made of sugared tea that is transformed by a symbiotic consortium of yeasts and bacteria. Polyphenols are expected to be responsible of several health benefits attributed to kombucha consumption, among other metabolites. This study investigated the impact of tea infusion time and of kombucha “fermentation”, on total phenolic content,