ZINC AND PHYTATE DISTRIBUTION IN PEAS - INFLUENCE OF HEAT-TREATMENT, GERMINATION, PH, SUBSTRATE, AND PHOSPHORUS ON PEA PHYTATE AND PHYTASE

The largest proportions of Zn and phytate, 88.7 and 97.1%, respectively, were in the Garfield pea cotyledon; the greatest concentrations were in the germ. Cooking peas by 2 different methods resulted in 13% phytate reduction. Peas incubated 6.5 h from 25.degree. to 80.degree. C yielded maximum phytate loss (25%) at 60.degree. C due to phytase activated hydrolysis. Germination (10 day) decreased pea phytate 75% and increased phytase activity 12-fold. Semi-purified germinated pea phytase showed temperature optimum at 45.degree. C, pH optimum of 5.2, 30% inhibition by 1 mM Pi, and substrate preference for PPi. Incubation of early germinated peas at optima pH and temperatures is suggested for maximum phytate reduction.