Étude de la flore levurienne de différents terroirs alsaciens

Color is one of the key elements in the marketing of rosé wines[1]. Their broad range of color is due to the presence of red pigments (i.e. anthocyanins and their derivatives) and yellow pigments, likely including polyphenol oxidation products. Clarifying agents are widely used in the winemaking industry to enhance wine stability and to modulate wine color by binding and precipitating polyphenols[2]. During this study, the impact of four different fining agents (i.e. two vegetal proteins, potatoe and pea proteins, an animal protein, casein, and a synthetic polymer, polyvinylpolypyrrolidone, PVPP) on Syrah Rose wine color and phenolic composition (especially pigments) was investigated. Color was characterized by spectrophotometry analysis using the CIELab system in addition to absorbance data. Fining using PVPP had the highest impact on redness (a*) and lightness (L*) parameters, whereas patatin strongly reduced the yellow component (b*) of the wine color. In parallel, the concentration of 125 phenolic compounds including 85 anthocyanins and derived pigments was determined by Ultra High Performance Liquid Chromatography coupled to elestrospray ionisaion triple-quadrupole Mass Spectrometry (UHPLC-QqQ-ESI-MS) in the Multiple Reaction Monitoring mode[3] .

Water stress triggers functional compartmentalization in grapevines, influencing how resources are allocated to different plant organs.

The winemaking industry generates a substantial amount of byproducts, including grape pomace, which is often discarded as waste. However, this seemingly useless material holds a wealth of bioactive compounds with potential health benefits. Recognizing the value of circular economy principles, this study delves into the comprehensive chemical analysis of aglianco grape pomace, aiming to transform this byproduct into a valuable resource.

Wine quality is influenced by grape maturity, typically monitored by measuring sugar content and acidity.

In France, the definition of appellations of origins is entrusted to the Institut National des Appellations d’Origine. (‘NAO). With the increase in price of appellations of origin vine­yards and considering the interests at stake, Institut National des Appellations d’Origine and the Institut National de Recherche Agronomique (INRA) established a work group in 1993 in order to study the “terroir-wine” relationship as precisely as possible, taking into account the knowledge acquired by researchers of the INRA and the experience in the field of the agents of the INAO.