Grape seed powder as an alternative to bentonite for wine fining

La région viticole de Mendoza est la principale zone vitivinicole d’Argentine qui se compose de 3 oasis (Nord, Valle de Uco, Sud). La première zone vitivinicole, située dans l’oasis Nord, est composée par les département de Luján de Cuyo et Maipu. C’est la zone de production la plus ancienne et la plus reconnue pour la qualité de sa production. Ce travail se porte plus particulièrement sur le département de Luján de Cuyo qui constitue le lieu traditionnel de production du Malbec argertin. Ce travail propose de caractériser les terroirs et de mettre en avant leurs typicités.

Sustainability is a key focus in viticulture, where managing abiotic and biotic stress presents a major challenge.

Epidermal Patterning Factors are a class of cysteine rich peptides known to be involved in many developmental processes. The role of EPF1, EPF2 and EPFL9 in controlling leaf stomata formation has been well described in model plants and cereals, and recently also in grapevine, while little is known about their activity in other organs. The aim of our study is to investigate whether VviEPFL9-2 can have a specific biological function in grapevine roots, where it resulted to be expressed. As grapevine is cultivated in the form of a grafted plant, we focused our study on the commonly used rootstock Kober 5BB (Vitis berlandieri x Vitis riparia). VviEPFL9-2 was edited in Kober 5BB plants using Agrobacterium tumefaciens transformation of embryogenic calli and the CRISPR/Cas9 technology. The phenotypic evaluation in greenhouse indicated that, as expected, the leaves of knock-out (KO) plants have a significant lower stomatal density compared to WT, associated with a lower stomatal conductance.

Flavonols are a class of flavonoid compounds derived from plant secondary metabolism. There they play different roles like antioxidants, internal regulators and UV screenings. In red wines, flavonols have increasingly received consideration by part of scientific and winemakers according their properties began to arise known. Among these stand out wine colour stabilization and their value as bioactive compounds. In this work the complete series of the acetylated and p-coumaroylated derivatives of the 3-O-glycosides of methoxylated flavonols, namely isorhamnetin, laricitrin and syringetin, have been identified in grapes and their respective wines from Vitis vinifera cv. Tannat.

The inherent variability of Nature poses challenges for researchers to draw clear conclusions from field experiments. Identifying and assessing adaptations to climate change requires agronomic field trials.