Enzymatic degradation of phytic acid in low-calore bread with different sources of phytases

Abstract

The present investigation was carried out to study the possibility of utilization of high phytase activity extracted from different plant sources to degradation of phytic acid in low calore (diabetic bread) bread contained high levels of phytates. The reduction of phytate by using the ordinary water without adding phytase extract (control) in dough mixing then, fermented to 45 min., was 17.2 and 22.1% of its initial value after fermentation and baking, respectively. The addition of phytase extract from germinated wheat, wheat germ and rice bran during dough mixing led to increase the hydrolysis of phytate and reduction its content in final diabetic bread. The obtained results by addition phytase extract from wheat germ showed highly increase in phytic acid degradation compared to germinated wheat extract. When half amount of water required for dough mixing was replaced by equal amount of phytase extract from defatted wheat germ, the phytate phosphorus levels in diabetic bread decreased by 90.6 % of its initial values. Addition of phytase extract prepared from rice bran to the doughs minimized the phytate content during fermentation by 62.7, 65.7 and 77.2% in the presence 10, 20 and 30 ml of rice bran phytase extract, respectively. It can be concluded that, the use of wheat germ phytase extract is better to reduce the phytate content in diabetic bread compared with germinated wheat and rice bran phytase extracts.