杜马斯燃烧法测定油料作物中粗蛋白质含量的 方法优化及其与凯氏定氮法的比较研究

目的建立杜马斯燃烧法测定油料作物中粗蛋白质含量的方法,并与凯氏定氮法进行比较。方法以芝麻、大豆、油菜和花生为研究对象,对杜马斯燃烧法的称样量和氧气系数进行优化。分别用杜马斯燃烧法和凯氏定氮法测定4种样品的粗蛋白含量,并对2种测试方法的结果进行比较分析。结果杜马斯燃烧法的测定值略高于凯氏定氮法,但2种方法的测定值间没有显著性差异(P0.05),杜马斯燃烧法比凯氏定氮法的测定精密度和准确度更高。测定结果的相关性分析表明两种方法的测定值呈显著相关(r~2=0.9988)。结论杜马斯燃烧法的精密度和准确度更好,可以替代凯氏定氮法测定油料作物的粗蛋白质含量。

Optimization of the Dumas combustion method for the determination of crude protein content in oil crops and comparison study of Dumas combustion method and Kjeldahl determination

Objective To establish the Dumas combustion method for the determination of crude protein content in oil crops, and compare the results by Dumas combustion method with Kjeldahl determination. Methods With sesame, soybean, rapeseed and peanut as samples, the sample mass and oxygen coefficient were optimized in Dumas combustion method. The crude protein content in 4 kinds of samples were determined by Dumas combustion method and Kjeldahl determination respectively, and the experimental results of the 2 methods were analyzed and compared. Results The measured values of Dumas combustion method were slightly higher than those of Kjeldahl determination. However, there was no significant difference for the results (P>0.05) between the above 2 methods. The Dumas combustion method had higher precision and accuracy than those of Kjeldahl determination. Correlation analysis of results from 2 methods showed the results of them were correlated significantly (r2=0.9988). Conclusion The Dumas combustion method had higher precision and accuracy, so it can replace the Kjeldahl determination for the determination of crude protein content in oil crops.