Study on Polyphenol Oxidase Activity in Different Parts of Purple Sweet Potato

Abstract

The basic study on activity of polyphenol oxidase (PPO) from different purple sweet potato (PSP) parts was mainly carried out here. The PPO activity and browning degree (BD) of PSP peel were higher than those of inner-tissue and intact sweet potatoes. The relativity between them was positive, and relativity coefficient was 0.9895. The activity of PPO extracted from sliced PSP increased initially and decreased afterwards, with the highest activity of PPO on the third day during storage. And BD increased very quickly as time went by, especially in the first three days. The relativity between PPO activity and BD was negative, and relativity coefficient was-0.8747.