Ashworth R B
J Assoc Off Anal Chem. 1987 Jan-Feb;70(1):80-5.
The Food Safety and Inspection Service procedure for determination of essential amino acid content of mechanically processed products from red meat animals and poultry is based on hydrolysis of a powder prepared by blending samples in acetone-chloroform. The hydrolysis procedure incorporates thioglycolic acid to prevent loss of tryptophan. Aliquots of prepared hydrolysates are injected into a liquid chromatographic system, using gradient elution on an ion-exchange column for separation. The system also uses post-column hypochlorite oxidation coupled with orthophthalaldehyde reagent and fluorescence detection. Modification of the elution program allows concurrent determination of tryptophan with minimal added cost. Chromatograms from beef, pork, and poultry products show adequate separation and quantitation of beta-alanine, 1-methyl-histidine, and 3-methyl-histidine, indicating that the procedure could be used to estimate muscle content of products. A colorimetric procedure for assay of hydroxyproline was introduced and validated as an adjunct method for protein quality estimation.
食品安全与检验局测定红肉动物和家禽机械加工产品中必需氨基酸含量的程序，是基于对通过将样品在丙酮 - 氯仿中混合制备的粉末进行水解。水解程序中加入巯基乙酸以防止色氨酸损失。将制备好的水解产物等分试样注入液相色谱系统，在离子交换柱上使用梯度洗脱进行分离。该系统还采用柱后次氯酸盐氧化结合邻苯二甲醛试剂和荧光检测。修改洗脱程序可在成本增加最少的情况下同时测定色氨酸。牛肉、猪肉和家禽产品的色谱图显示，β-丙氨酸、1-甲基组氨酸和3-甲基组氨酸有足够的分离度和定量结果，表明该程序可用于估算产品的肌肉含量。引入并验证了一种比色法测定羟脯氨酸，作为蛋白质质量评估的辅助方法。
