Berkowitz D B, Webert D W
J Assoc Off Anal Chem. 1987 Jan-Feb;70(1):85-90.
A number of methods may be used for determining soy flour in meat products. Highly purified soy products are more difficult to determine because the nonprotein components used to quantify the flour are reduced. Immunoassays have been used to directly measure protein content of soy products. Immunological methods for determination of soy proteins in meat are complicated by changes in the structure of the soy proteins during processing. These changes alter the available epitopes, changing the immunoreactivity of soy proteins. The epitopes available are dictated by the details of the processing. Other workers circumvented this problem by denaturing the soy protein with urea and mercaptoethanol, and then removing these agents by dialysis; whatever the initial protein conformation, all soy samples came to the same final conformation after the denaturing agents were removed. The assay used antibody made against the "renatured protein." These steps made the assay long and laborious. Attempts to develop a rapid assay were complicated by the same protein denaturation problems. Sodium dodecylsulfate gel electrophoresis coupled with immunoblotting may be the best quantitative approach.
有多种方法可用于测定肉制品中的大豆粉。高度纯化的大豆制品更难测定，因为用于定量面粉的非蛋白质成分减少了。免疫测定法已被用于直接测量大豆制品的蛋白质含量。肉类中大豆蛋白的免疫测定方法因加工过程中大豆蛋白结构的变化而变得复杂。这些变化改变了可用的表位，从而改变了大豆蛋白的免疫反应性。可用的表位由加工细节决定。其他研究人员通过用尿素和巯基乙醇使大豆蛋白变性，然后通过透析去除这些试剂来规避这个问题；无论初始蛋白质构象如何，去除变性剂后所有大豆样品都达到相同的最终构象。该测定使用针对“复性蛋白”制备的抗体。这些步骤使得测定过程漫长且费力。由于同样的蛋白质变性问题，开发快速测定方法的尝试也很复杂。十二烷基硫酸钠凝胶电泳结合免疫印迹可能是最好的定量方法。
