Wine professionals are interested in the quality of the grape, in particular of its phenolic composition and their potential of extraction. In this context, the main objective here is to evaluate the contribution of the mechanical properties of grapes to the extractability of the phenolic compounds. The first step was to follow the evolution of major phenolic of Cabernet Franc grapes, belonging to different vineyards as well as their extractability during the maturation over two vintages. A second approach related to the study of the evolution of the mechanical properties of the grapes during maturation by TPA and puncture tests on whole berry and by destructive compression on seeds was proposed. However the experimental and statistical approach followed in this study proved limited and did not allow to lead to a comprehensive view although having been able to highlight during the maturation of the correlations when the analyses were carried out on grapes coming from the same vineyard or the same vintage. Indeed various correlations were generated but none could be widespread. The nature of the bonds being able to exist seems dependent on the vintage and hardly being able to be extrapolated from one vineyard to another. Our results show that the evolution and the extractability of the phenolic compounds as well as the mechanical properties of the grape are above all related on the vintage and to a lesser level to the vineyard.
STUDY OF THE EVOLUTION AND THE EXTRACTABILITY OF PHENOLS COMPOUNDS IN MODEL SOLUTION DURING MATURATION- RELATIONSHIP WITH MECHANICAL PROPERTIES OF GRAPES