Evolution of Polyphenols during Syrah Grapes Maceration: Time versus Temperature Effect

Chantal Ghanem (1, 2) , Patricia Taillandier (3) , Ziad Rizk (1, 2) , Nancy Nehme (4) , Jean-Pierre Souchard (3) , Youssef El Rayess (1)

1 Holy-Spirit University of Kaslik [Jounieh]
2 LARI - Lebanese Agricultural Research Institute
3 LGC - Laboratoire de Génie Chimique
4 LU / ULB - الجامعة اللبنانية [بيروت] = Lebanese University [Beirut] = Université libanaise [Beyrouth]

The effect of maceration time and temperature on the phenolic compounds of Syrah grape musts was studied. Pre-fermentation cold (10 °C) and heat maceration (60, 70 and 80 °C) were applied and compared to traditional maceration (control, 25 °C). The macerations were monitored and the kinetic profile of the maceration was studied by taking samples at 0, 2, 4, 8, 24 and 48 h. The results showed that heat treatment had the most significant effect on the extraction of total polyphenol. A significant loss of anthocyanin content was observed when the maceration was extended beyond eight hours at high temperatures, while longer maceration times seemed to favor the extraction of tannins. A principal component analysis showed that independently of the vinification technique, and for the same grape varieties, different winegrowing regions and harvest years affected the phenolic composition of the grape skin

Mots clés: Maceration; Phenolic compounds; Tannins; Anthocyanins; Syrah

Domaines: Ingénierie des aliments; Génie chimique; Génie des procédés

Chantal Ghanem, Patricia Taillandier, Ziad Rizk, Nancy Nehme, Jean-Pierre Souchard, et al.. Evolution of Polyphenols during Syrah Grapes Maceration: Time versus Temperature Effect. Molecules, 2019, 24 (15), pp.2845. ⟨10.3390/molecules24152845⟩. ⟨hal-02292046⟩