Interest in measuring the grape texture to characterise grapes from different cultivation areas – Example of Cabernet franc from the Loire Valley

A two-bite compression test was applied on Cabernet franc grapes during two harvest seasons. The evolution of the texture parameters from véraison to harvest was studied and a new mechanical ripeness notion was introduced. The ripeness stage and the parcel type effects on the texture properties were investigated, considering ten sampling dates and three parcels. A sensory description of the same grape samples was also performed. The compression test and the sensory evaluation allowed discrimination between ripeness levels and parcels types. The influence of the parcel type and the harvest season were highlighted. Indeed each parcel behaved differently from the others toward climatic conditions. High correlations were observed between some sensory descriptors and texture indices in 2005. This work confirmed the interest of the grape texture as an indicator of the grape ripeness in relation with the terroir.