冻猪肉中挥发性盐基氮含量测定的不确定度评定  

Evaluation of Uncertainty in Determination of Total Volatile Basic Nitrogen in Frozen Pork by Automatic Kjeldahl Apparatus Method

作　　者：陈韵 陈桂云 黎颖欣 叶春常 陈梓聪 CHEN Yun;CHEN Guiyun;LI Yingxin;YE Chunchang;CHEN Zicong(Guangzhou Institute of Food Inspection,Guangzhou 511400,China)

机构地区：[1]广州市食品检验所,广东广州511400

出　　处：《现代食品》2022年第13期168-171,共4页Modern Food

摘　　要：目的:对自动凯氏定氮仪法测定冻猪肉中挥发性盐基氮含量的不确定度进行分析和评定。方法:建立不确定度评定数字模型,分析并计算各不确定度分量,从而得出挥发性盐基氮的合成不确定度和扩展不确定度。结果:冻猪肉中挥发性盐基氮含量为12.3 mg/100 g,扩展不确定度为0.4 mg·kg^(-1)(95%,k=2)。结论:采用自动凯氏定氮仪法测定冻猪肉中的挥发性盐基氮,标液浓度引入的不确定度分量影响最大,测量重复性和滴定体积的误差引入的不确定度的影响次之,而样品称量引入的不确定度最小。Objective:To evaluate the uncertainty of total volatile basic nitrogen in frozen pork by Automatic Kjeldahl Apparatus method.Method:A mathematical model for uncertainty evalution was established,the sources of uncertainty were analyzed,and the combined uncertainty and expanded uncertainty were calculated.Result:The content of total volatile basic nitrogen in frozen pork was 12.3 mg/100 g,and the expanded uncertainty was 0.4 mg·kg^(-1)(95%,k=2).Conclusion:The main factor influencing the uncertainty in determination of total volatile basic nitrogen in frozen pork by Automatic Kieldahl Apparatus method is the concentration of standard titration solution,followed by the repeatability of measurement and deviation of the titration volume,while the uncertainty caused by sample weighing has minimal effect.

关 键 词：自动凯氏定氮仪法 冻猪肉 挥发性盐基氮 不确定度 

分 类 号：TS251.7[轻工技术与工程—农产品加工及贮藏工程]