title: Influence of grape density and harvest date on changes in phenolic composition, phenol extractability indices, and instrumental texture properties during ripening.
abstract: Changes in the phenolic composition, phenol extractability indices, and mechanical properties occur in grape berries during the ripening process, but the heterogeneity of the grapes harvested at different ripening stages affects the reliability of the results obtained. In this work, these changes were studied in Nebbiolo grapes harvested during five consecutive weeks and then separated according to three density classes. The changes observed in chemical and mechanical parameters through the ripening process are more related to berry density than harvest date. Therefore, the winemaker has to select the flotation density according to the objective quality properties of the wine to be elaborated. On the other hand, the stiffer grapes were associated with a higher accumulation of proanthocyanidins. The harder grapes provided the higher concentration and extractability of flavanols reactive to vanillin, whereas the thicker ones facilitated the extraction of proanthocyanidins.
authors: DIVAPRA-Food Technology Sector, University of Turin, Grugliasco (TO), Italy.
authors: Luca
authors: L
authors: Rolle
authors: Susana Río
authors: SR
authors: Segade
authors: Fabrizio
authors: F
authors: Torchio
authors: Simone
authors: S
authors: Giacosa
authors: Enzo
authors: E
authors: Cagnasso
authors: Fabio
authors: F
authors: Marengo
authors: Vincenzo
authors: V
authors: Gerbi
mesh_terms: D000872:Anthocyanins / Q000032:analysis; D001696:Biomechanical Phenomena; D055598:Chemical Phenomena; D005638:Fruit / Q000033:anatomy & histology / Q000737:chemistry* / Q000254:growth & development*; D010636:Phenols / Q000032:analysis*; D027843:Vitis; D014920:Wine / Q000032:analysis
chemical_list: D000872:Anthocyanins; D010636:Phenols