Abstract: Albedo was chopped up to the diameter of 0.5～1 mm, which was separated from citrus fruits. The thin albedo was soaked in 0.2 mol/L sodium phosphate buffer at pH 6.0 for about 24 hours. Then, the resultant suspension for studying the POD characteristics was filtered through a four-fold layer of muslin. The results showed that POD activities among severl species of citrus are different relatively, and the optimum pH and temperature for the POD are 5.0 and 40～60 ℃, respectively. The POD activity increases with the increase of substrate concentration (H2O2) concentration, and reaches saturaed point at 0.07% H2O2. Moreover, both 0.1% VC and 0.5% Na2SO3 are strong inhibitors for POD activity in Tahiti albedo.

Key words: albedo of citrus fruit, POD, characteristics