三氯乙酸沉淀法与硫酸铜沉淀法在液态奶蛋白质检测中适用性研究  

TCA precipitation method and cupricsulfate precipitation in the milk protein detection applicability of the study

作　　者：牛巍[1] 侯彩云[1] 祝晓芳[1] 刘莹[1] 

机构地区：[1]中国农业大学食品科学与营养工程学院,北京100083

出　　处：《中国乳品工业》2008年第9期59-61,共3页China Dairy Industry

摘　　要：分别利用三氯乙酸沉淀蛋白法和硫酸铜沉淀蛋白法与凯氏定氮法相结合,对液态奶蛋白质进行测定。比较研究了亚硝酸钠、硝酸铵、尿素、甘氨酸、水解蛋白等几种非蛋白氮对这两种蛋白沉淀法的影响,并对这两种方法进行比较。结果表明,对于液态奶蛋白氮的测定,三氯乙酸沉淀法与硫酸铜沉淀法在数值上存在着显著性差异,三氯乙酸沉淀法能更有效地排除非蛋白氮对液态奶蛋白氮测定的影响。Using Kjeldahl method to determine the content of protein which had been precipitated by trichloroacetic acid and Cupricsulfate. Comparing with the two precipitated methods and studying on Sodium Nitrite ,Ammonium nitrate ,Urea ,Glycin,Proteinum hydrolysatum effected on the two methods. It is shown from the results that the two precipitated protein methods exist significant diversity and trichloroacetic acid is more better than cupricsulfate on precipitating protein.

关 键 词：液态奶 三氯乙酸 硫酸铜 凯氏定氮 

分 类 号：TS252.7[轻工技术与工程—农产品加工及贮藏工程]