Typologie des paysages de vigne: un outil de planification

The use of pectinolytic enzymes in winemaking is state of the art. These enzymes catalyse the degradation of pectic substances through depolymerization (hydrolases and lyases) and de-esterification. As a result, it supports the extraction of juice and facilitates filtration. It has also been shown in winemaking that the presence of pectinolytic enzymes improves the stability, taste, texture, colour and aroma of products. With regard to enzymes currently applied in winemaking, enzymes derived from filamentous fungi dominate the enzyme industry. Fungal-based pectinolytic enzymes specifically require purification from the culture medium to eliminate unwanted side reactions, which is poorly sustainable. Some non-traditional yeast strains have been reported to exhibit pectinolytic activities. Therefore, the direct use of pectinolytic yeast during wine fermentation process can be an attractive and alternative source for the use of enzymes as input.

Color is a key quality trait for grape berry and the producing wines. Berry color of red genotypes is mainly determined by the quantity and composition of anthocyanins accumulated in the skin and/or pulp. Both genetic and environmental factors could influence the quantity and composition of anthocyanins, while the underlying mechanisms are not fully clear. To explore the mechanisms underlying the diversity of anthocyanin accumulation in grape berry, we compared two grapevine genotypes showing distinct sensitivities to ABA-induced anthocyanin biosynthesis, where one genotype showed minor responses to exogenous ABA application while the other showed significant increase in anthocyanins after exogenous ABA application.

Una de las biotecnologías más potentes para disminuir el pH en vinos de zonas cálidas y en variedades de pH elevado es el uso de la levadura no-saccharomyces lachancea thermotolerans. Esta especie es capaz de formar ácido láctico a partir de azúcares, reduciendo al mismo tiempo ligeramente el grado alcohólico. Por lo tanto, mejora dos de los principales problemas de los vinos de regiones afectadas por el calentamiento global. El ácido láctico es un ácido orgánico con una buena integración sensorial en el sabor del vino, y también química y biológicamente estable durante el envejecimiento del vino.

The importance of the non-Saccharomyces yeasts (NSY) in winemaking has been extensively reviewed in the past for their aromatic or bioprotective capacity while, recently their antioxidant/antiradical potential has emerged under winemaking conditions. In the literature the antioxidant potential of NSY was solely explored through their capacity to improve glutathione (GSH) content during alcoholic fermen- tation [1], while more and more studies pointed out the activity of the non-glutathione soluble fraction released by yeasts [2].

Un programme de recherche concernant les facteurs naturels et humains des terroirs viticoles a été développé dans le vignoble A.O.C. de l’Anjou, sur une surface d’environ 30.000 Ha