Relation between calcium content and resistance to enzymatic digestion of the skin during grape ripening

The evolution of calcium during grape berry development and ripening is irregular. The changes in calcium content of cell wall will have important consequences, mainly on the skin which is responsible for the berry reaction during attack pathogenic fungus like Botrytis cinerea. Our study about the evolution of the susceptibility to enzymatic digestion of berry skin from different cultivars during ripening reveals that the more important the cell wall calcium content, the less susceptible is the skin. Precisely, cell wall cohesion of the skin tissue results in the chelation state of the pectic substances.