BLANCHING EFFECT ON POLYPHENOL OXIDASE ACTIVITY IN TABLE BEETS

Table beet polyphenol oxidase (PPO) causes undesirable color in underblanched products. The effects of pH and temperature on PPO activity were studied. Varietal differences and the effects of blanching on PPO activity of table beets were measured. The enzyme was most active at pH 7.0 and temperature 25°C. The rate of heat inactivation increases rapidly with increasing temperature and follows pseudo‐first order kinetics. The enzyme activity varied among different cultivars of table beets. Water blanching deactivated the enzyme but the time required for a complete inactivation varied according to the size of table beets. Copyright © 1979, Wiley Blackwell. All rights reserved