丙酸钙含量测定方法的比较研究及对我国强制性标准修订的建议

COMPARATIVE STUDY ON DETERMINATION METHODS OF CALCIUM PROPIONATE AND SUGGESTIONS FOR THE REVISION OF CHINA’S MANDATORY STANDARDS

建立了液相色谱法测定丙酸钙含量的实验方法。对试样进行酸化处理后,利用C18液相色谱柱、紫外检测器、外标曲线定量法,测定了丙酸根的含量,并计算得到丙酸钙含量。采用液相色谱法对质量分数为99.7%、不确定度0.6%的丙酸钙标准物质进行多次测试,结果表明丙酸钙质量分数99.74%~99.82%,相对标准偏差0.03%。对3组实际试样、分别采用滴定法和液相色谱法的进行重复性实验,相对标准偏差分别是0.060%和0.099%(第1组)、0.070%和0.085%(第2组)、0.075%和0.13%(第3组)。改进试样制备方式、采用自动进样等可进一步提高液相色谱法的可重复性。液相色谱法的建立为食品安全领域丙酸钙强制性标准的修订提供依据。

A test method for the determination of calcium propionate content by liquid chromatography was established.After the sample was acidified,it was quantified using a C18 liquid chromatography column,an ultraviolet detector,and an external standard curve to determine the content of propionic acid and calculate the calcium propionate content.The liquid chromatography method was used to test the calcium propionate standard substance with a content of 99.7%and an uncertainty of 0.6%.The results showed that the calcium propionate content was 99.74%to 99.82%,with a relative standard deviation of 0.03%.Titration and liquid chromatography are used to test samples on the market.Liquid chromatography is aimed at the active ingredients in calcium propionate to prevent counterfeit and shoddy products.For three groups of actual samples,the titration method and liquid chromatography were used to perform repeatability tests.The relative standard deviations were 0.060%and 0.099%(first group),0.070%and 0.085%(second group),0.075%and 0.13%(third group).Improving the sample preparation method and using automatic injection can further improve the repeatability of liquid chromatography.The establishment of liquid chromatography provides the basis for the revision of the mandatory standard of calcium propionate in the field of food safety,and it is expected to solve the problems of food safety management and effective law enforcement in China.