Physico-mechanical evaluation of the aptitude of berries of red winegrape varieties to resist the compression in carbonic maceration vinification.

By texture analysis tests, the berry aptitude to resist the rupture under compression load supported during intracellular fermentation was studied for twenty-three red winegrape varieties. The softest berries were associated with Ancellotta (1.72 N), Dolcetto (1.79 N), Gamay (2.26 N) and Schiava gentile (2.29 N) cultivars. The hardest berries corresponded to Franconia and Bonarda cultivars (4.02-4.03 N). High resistance to splitting was also detected for,Grenache, Raboso, Marzemino, Negramaro, Montepulciano and Croatina cultivars (3.50-3.95 N). The differentiating power of the mechanical variables of the whole berry and skin was assessed by univariate and multivariate analysis. Relationships among the instrumental berry hardness and other physical and mechanical properties were also investigated. The results obtained suggest that the manufacture of carbonic macerated wines should be planned considering the berry hardness, and it represents a new variable that should be considered in selecting which is the most appropriate winegrape variety to elaborate these wines.