Enzymatic browning and its control during potato pulp powder processing

Effects of temperature, pH value, substrate concentration and enzyme inhibitors on polyphenol oxidase (PPO) activity in potato pulp were investigated to control enzymatic browning of potato pulp. The results showed that the optimum pH value of PPO activity of potato pulp was 6.6, the optimum temperature of PPO activity was 35 °C, and the substrate (o-dihydroxybenzene) concentration 0.8%. Treatments of ascorbic acid, citric acid and Na
₂
SO
₃
restrained the PPO activity significantly. Treatments of NaCI also restrained the PPO activity. The optimum treatment for controlling enzymatic browning was ascorbic acid 0.35
⁰
/
₀₀
+citric acid 1.2% +Na
₂
SO
₃
0.25
⁰
/
₀₀
; The activity to inhibite potato pulp browning was as follows: ascorbic acid >; citric acid >; sodium sulfite. The product which was made had natural color and had smell and taste of potato pulp.