高梁中单宁含量测定方法的研究

本文所报道的高梁中单宁含量测定方法的国家标准，是在ISO－9648方法基础上起草制定的，结合我国基层实验室的实际情况，针对ISO－9684方法的各种测定条件，做了适当的修改，对修改后的测定条件，单宁标准品，样品用量，样品粉碎粒度，单宁提取时间，提取液的分离方式，显色反应时间等进行了反复的验证，经过对内蒙古自治区和吉林省18个品种高梁样品单宁含量的测定，结果表明，标准偏差为0－0．03，变异系数CV（％）为0－2．6，由北京谷物油脂化学研究所和成都粮食集藏研究所对其中9个品种单宁含量做了验证，结果表明，三个实验室测定值的平均相对偏差（％）为0．5－3．2，三个实验室测定值的变异系数（％）为2．8－5．8。

Studies on theDetermination of Tannin Content in Sorghum

National Standard for determination of tannin content in sorghum was drafted on the basis of International Standard ISO 9648.According to the practical laboratory condition in China,some factor parameters in the International Standard ISO 9648 were modified through a series experiments, which included tannin acid for the calibration curve,the weight of test sample,the particles size of sample crushed,the time for extracting tannin from test sample,the separating ways for supernatant liquid and the color reaction time. To prove the modified procedure,the tannin contents of eighteen varieties from Inner Mongolia Autonomous Region and Jilin province were determined.The standard deviation were0～0.03,and variations coefficient (%)were 0～2.6.An inter-laboratory test,carried out in Beijing Cereal and Oil chemistry Research Institute and Chengdu Grain Storage Research Institute,gave the following statistical results:mean deviation of the results from three laboratories were 0.5～3.2,and coefficient variation(%)were2.8～5.8.