豆制食品中胰蛋白酶抑制剂活性测定方法的改进

在ISO 14902:2001《动物饲料-大豆制品胰蛋白酶抑制剂活性的测定》方法的基础上，对影响豆制食品中胰蛋白酶抑制剂活性测定的一些关键因素进行改进与补充，为豆制食品中胰蛋白酶抑制剂活性的测定提供新方法。采用分光光度法，对样品提取方法、样品脂肪含量、提取液过滤与否影响、结果计算公式等进行相应改进研究，使改进后的测定方法操作简便快速、变异系数小，适用性强、计算方式简单、计算结果准确、检测速度提高并具有足够高的重复性等优点，适宜日常豆制食品检验工作的开展。

Improvement of the Animal Feeding Stuffs — Determination of Trypsin Inhibitor Activity of Soybean Products (ISO 14902:2001)

A spectrometric method has been established and announced by ISO for determining trpsin inhibitor activity of soybean-based animal feed. The method, however, has several defects, which restrict its application and popularization. Therefore this study aimed to improve this method to achieve rapid and accurate determination of trpsin inhibitor activity of soybean-based food products such as soybean milk powder, etc. The improvement mainly focused on sample preparation. The results showed that the determination results were basically identical when sample was crushed to particle sizes of 80 and 100 mesh, higher than those of the samples with the particle size less than 80 mesh. Removal of fat from sample and filtration of the prepared trpsin inhibitor solution had no significant effects on determination result. The optimal extraction effect of trpsin inhibitor from sample could be achieved by stirring the mixture of the sample and distilled water for 30 min. The improved method has high accuracy and precision, and is time-saving.