| Abstract: | Activation of endogenous or addition of exogenous phytases during food processing gives a chance to reduce the phytate content in the final product to a nutritionally acceptable level. Optimal conditions for the endogenous phytases of black beans, this is 60C and pH 6.0, resulted in a 55% reduction in 1P6 after soaking and cooking. the sum of 1P5 and 1P5 was reduced by 54%. 1P6 reduction was most extensive when black beans were soaked at 50C while adding exogenous phytases during the last 2 h of soaking. After soaking and cooking 1P6 was degraded by 85% and the sum of 1P6 and 1P5 was reduced by 82 % compared to the values in raw beans when adding Escherichia coli phytase. Using rye phytase the values were estimated to be 73% and 70%, thereby a clear accumulation of IP4 occurred. Thus, a significant improvement in reduction of mnyo-inositol phosphates with adverse effects on mineral bioavailability has been achieved in comparison to the usual household procedure. |
