几种测定油料饼粕粗蛋白含量方法的探讨

采用国家标准规定的凯氏定氮法、改进后的凯氏定氮法以及双缩脲法同时测定油料饼粕中粗蛋白含量，并对三种方法进行比较。结果表明：改进后的凯氏定氮法同国际法相比结果偏高，更皎皎于饼粕中实际粗蛋白含量；采用双缩脲法有测定结果相对平均偏差较大，但操作简便，效率高，更适合于生产厂家进行快速测定大量样品时使用。

Discuss on Methods about Determining Crude Protein Content in Oil Cake

In this paper,kjeldahl method regulated by national standard?improved kjeldahl method and biuret method are used to measure the crude protein content in oil cake simultaneously.After comparing the results,we can draw a conclusion that the data acquired from improved kjeldahl method is bigger than kjeldahl method regulated by national standard and more approximate to the truth of crude protein content.On the other hand,the relative average deviation of the data gained from biuret method for a great amount of samples is bigger.However,biuret method has the advantages of simple operation and being effective,so it suited to be used as a quick measuring method in feed mill.