Metabolomics of Vitis davidii Foëx. grapes from southern China: Flavonoids and volatiles reveal the flavor profiles of five spine grape varieties

AIM: Study the chemical and sensory parameters of fifty commercial white wines elaborated with different techniques (fermented in oak barrel and aged on lees (FB+AL); aged on lees (AL); and without aging (WA)) and different grape varieties (Verdejo, Sauvignon blanc and Godello).

Context and purpose of the study. The vine nursery sector is undergoing a transformation to meet growing environmental and sanitary demands.

AIM The main lead exposure route is the intake of contaminated food, water, and alcoholic beverages, in particular wine. At the gastric level, Pb is transformed into a soluble compound which, when conveyed into the bloodstream, is the long-term cause of saturnism, intoxication with neurotoxic, nephrotoxic and hematopoietic effects, and with the neurological developmental delay of children. Pb is classified by the International Agency for Research on Cancer as a 2A class, possible carcinogenic to humans. In an opinion on possible health risks, CONTAM considered that cereals, vegetables, drinking water, and wine give a greater contribute to dietary exposure to Pb in Europe. Large quantities of wine, beer, and other alcoholic products drinking can increase daily Pb intake above the maximum permitted levels.

Phenolic acids are phytochemicals that are expansively distributed in daily food intake. Phenolic acids are involved in various physiological activities, such as nutrient uptake, enzyme activity, protein synthesis, photosynthesis, and cytoskeleton structure in seeds, leaves, roots, and stems. Also exhibit antibacterial, antiviral, anticarcinogenic, anti-inflammatory, and vasodilatory activities due to their antioxidant property.

Malolactic fermentation (MLF) is a desired process to decrease acidity in wine. This fermentation, carried out mostly by Oenococcus oeni, is sometimes challenging due to the wine stress factors affecting this lactic acid bacterium. Wine is a harsh environment for microbial survival due to the presence of ethanol and the low pH, and with limited nutrients that compromise O. oeni development. This may result in slow or stuck fermentations. After the alcoholic fermentation the nutrients that remain in the medium, mainly released by yeast, can be used in a beneficial way by O. oeni during MLF.