Thermostability of Victoria grape (Vitis vinifera ssp. sativa) polyphenoloxidase
Rapeanu, G.; Van Loey, A.; Smout, C.; Hendrickx, M.
Communications in Agricultural and Applied Biological Sciences 69(2): 231-234
2004
ISSN/ISBN: 1379-1176 PMID: 15560229 Document Number: 581039
The thermostability of polyphenol oxidase (PPO) from white grapes cv. Victoria was determined at 25-90 degrees C for 10 minutes. Ten minutes heating at 60 degrees C reduced the PPO activity in the grape extract by 50%. The enzyme was almost completely inactivated at 70 degrees C after 10 minutes of thermal treatment. Results are presented on the detailed inactivation kinetics of grape PPO at 55-65 degrees C.