Pink discoloration of canned pears: role of procyanidin chemical depolymerization and procyanidin/cell wall interactions.

After canning, pear pieces turn occasionally from whitish-beige to pink. Conditions were set up to obtain this discoloration systematically and investigate its mechanism. Canned pears showed a significantly lower L* coordinate compared with fresh pears, and the L* coordinate of canned pears decreased with decreasing pH.