[Tannins of grapes to stabilize the colour]

anthocyane anthocyanins antocianinas antocianine color colore colour conservazione couleur laboratory experimentation polifenoles polifenoli polyphenol polyphenols preservation raisin de cuve red wines taninos tannin tannini tannins uvas para vino uve da vino vin rouge vini rossi vinification vinificazione vino tinto wine grapes winemaking