Characterisation of stem extracts of various grape varieties obtained after maceration under simulated alcoholic fermentation

The removal of stems prior to maceration during red winemaking is generally associated with an improvement in wine quality. However, recent years, increased interest the use has been observed among winegrowers. Different advantages this practice have listed literature. In order better understand their role winemaking, ten grape varieties from different winegrowing regions Switzerland were studied determine which minerals, acids and polyphenols are extracted under simulated alcoholic fermentation. composition extracts revealed differences between varieties. addition, growing conditions terroir seem influence on compounds stems, especially mineral such as potassium copper. Among polyphenols, phenolic proanthocyanidins mostly found stem extracts, caftaric acid, catechin procyanidin B1. Their concentrations significant compared average values wines.