定量核磁氢谱法快速测定食用醋中乙酸含量  

Rapid determination of acetic acid content in vinegar using quantitative ^(1)H NMR method

作　　者：甄少波[1] ZHEN Shaobo(China University of Labor Relations,Beijing 100048)

机构地区：[1]中国劳动关系学院,北京100048

出　　处：《中国食品添加剂》2022年第5期148-153,共6页China Food Additives

基　　金：中国劳动关系学院一般科研项目(20XYJS010);教育部教育教学改革专项(JYJG202002)。

摘　　要：建立食用醋中乙酸含量的快速定量分析方法。采用核磁共振氢谱(^(1)H nuclear magnetic resonance,^(1)H NMR),对多种食用醋进行了测定。核磁共振氢谱(^(1)H-NMR)测定参数为:温度25℃,谱宽2~14ppm,脉冲角度45度,脉冲延迟时间3s,采样时间2s,扫描次数16次。实验结果表明,在优化的测试条件下,目标物与内标物定量特征峰面积比1∶3~4∶1范围内,该方法表现出良好的线性关系,线性回归方程为Y=-0.01996+0.01732X(R=0.9999);精密度和重复性实验相对标准偏差(RSD)分别为0.059%和0.249%;样品加标回收率为97.8%~101.4%,平均偏差0.9%。该方法样品需求量小,结果稳定可靠,是一种简便、快捷的食用醋中乙酸含量的检测方法。A quantitative analysis method for the content of acetic acid in vinegar by ^(1)H-NMR spectroscopy was established.^(1)H-NMR working conditions are:temperature 25℃,spectrum width 2~14ppm,pulse angle 45 degrees,pulse delay time 3s,sampling time 2s,scanning times 16.The experiment results show that under the optimized test conditions,the quantitative characteristic peak area ratio of the target substance and the internal standard substance is within the range of 1∶3~4∶1,The method has a good linear relationship.The linear regression equation is Y=-0.01996+0.01732X(R=0.9999);the relative standard deviation(RSD)of the precision and repeatability experiment were 0.059%and 0.249%,respectively;the sample recovery rate was 97.8%~101.4%,and average deviation was 0.9%.The method only requires a small amount of sample,and results are stable and reliable.It is a simple and quick method for detecting the content of acetic acid in vinegar.

关 键 词：核磁共振氢谱 食用醋 内标法 定量核磁 乙酸 

分 类 号：TS264.2[轻工技术与工程—发酵工程]