外源植酸酶对面粉的酶解条件优化

以无机磷含量为评价指标，以酶解温度、酶解pH值、酶解时间和植酸酶添加量为影响因素对帝斯曼、昕大洋、罗氏三种外源植酸酶(分别记为酶1、酶2和酶3)在面粉中的作用效果进行单因素试验。结果表明：三种外源植酸酶在不同条件下均有相一致的适宜酶解作用范围，分别为酶解温度50～60℃、酶解pH5.0～6.0、酶解时间约4h、外源酶添加量约0.5%，其中外源酶2较其他两种外源植酸酶在同等酶解作用条件下具有更好的作用效果。因此对外源酶2进一步以酶解温度、酶解pH值和酶解时间为三因素进行正交试验。结果发现各影响因素的主次顺序分别为酶解温度>酶解时间>酶解pH值，其最佳酶解条件为酶解温度55℃、酶解时间4.5h、pH5.5，此时磷利用率高达79.1%。

Enzymolysis of Phytate in Wheat Flour with Exogenous Phytases

Single factor experiments were conducted to explore effects of three reaction parameters, including temperature, pH and time on release of inorganic phosphorus from phytate in wheat flour hydrolyzed by various exogenous phytases, namely DSM (Enzyme 1), Xindayang (Enzyme 2) and Luoshi (Enzyme 3). Subsequently, based on this, hydrolysis conditions of the most efficient one of the enzyme preparations were optimized for maximizing inorganic phosphorus content in wheat flour by orthogonal array design. These enzymes were found to perform hydrolysis effects under the following identical conditions: approximate 4 h reaction at 50－60 ℃ and pH 5.0－6.0 with a dose of 0.5%, among which, Enzyme 2 exhibited the best hydrolysis effect. An optimized Enzyme 2-catalyzed hydrolysis for 4.5 h at 55 ℃ and pH 5.5 yielded a phosphorus utilization ratio of 79.1%, which was affected by hydrolysis conditions in the following order of temperature ＞ reaction time ＞ pH.