Effect of ripening on protein content and enzymatic activity of Crimson Seedless table grape

► The year had an effect on the evolution of protein content, PPO and POD activity and °Brix in Crimson Seedless. ► The increase in protein synthesis observed after veraison is not related to PPO and POD activity. ► The maximum in specific activity at veraison may be correlated with changes in protein and anthocyanin content that take place during colour synthesis.