The peroxidase enzyme activity of some vegetables and its resistance to heat

The peroxidase enzyme activities of some fresh vegetables (cabbage, leeks, carrot, spinach, celery, squash, potatoes, onions and green beans) were determined. The peroxidase activities of cabbage and green beans were high. Onions showed very little peroxidase activity. The vegetables were blanched in hot water at 75°G, 85° and 95°C. Peroxidase inactivation was faster at the higher temperature blanch. Blanching of green beans, potatoes and squash at 75°C for 30 min was not sufficient for complete inactivation of peroxidase enzyme. Peroxidase enzyme inactivation was also affected by the type of vegetable and the size of vegetable pieces.