Browning of Peeled Tubers of Taro (Colocasia esculenta)

Abstract

Distribution of polyphenolic substances and polyphenol oxidase (P.O.) in the tubers of taro (Colocasia esculenta) was investigated in relation to the browning of the peeled tubers. The concentration of polyphenolic substances was higher in the surface part than in the center part of the tubers, and in the main tubers than in the branch tubers. On the other hand, the activity of P.O. was lower in the surface part than in the center part, and in the main tubers than in the branch tubers. The P.O. was not inhibited by NaCl at the concentration of 1% but the enzyme was easily inactivated under pH 4. The significant roles of the phenolic substances and the P.O. in the browning reaction of the peeled tubers were discussed.