全自动电位滴定法测定有色液态食品中的糖含量

Determination of sugar content in colored liquid food by automatic potentiometric titration

本论文针对国标法测定糖含量所采用的手工滴定法存在不适合深色样品的缺点,研究采用高温氧化还原电极的全自动滴定法进行替代的可能性。首先通过测定3个含酒精饮料,研究样品中的酒精对全自动滴定结果的影响,结果表明有色液态样品中所含酒精对全自动电位滴定法测定结果没有影响;采用全自动电位滴定法测定了9个有色液态食品(包括7个含酒精饮料和2个碳酸饮料)的糖含量,相对标准偏差(RSD)、回收率分别为0.124%～1.637%、96.0%～104.6%,并将结果与国标方法的结果进行了比对,相关系数r达到0.99997,说明全自动电位滴定法作为糖含量测定的一种新方式,其精密度和准确度均满足要求,可以取代传统手工滴定法。

The traditional manual titration method for determination sugar is not so suitable for the dark samples to overcome this shortcoming.A replace method of automatic potentiometric titrator equipped with high temperature redox electrode was studied.Firstly,the effect of alcohol on the determiantion result was stuidied by detecting 3 kinds of alcoholic beverage,which showed no effect.Then the sugar content of 9 kinds of colored liquid food,including 7 alcoholic beverage and 2 sodas,were measured by automatic potentiometric titration.Their relative standard deviation（RSD）and recoveries were 0.124% ~ 1.637% and 96.0% ~ 104.6%,respectively.The correlation between automatic potentiometric titration and manual titration was 0.99997.Our result showed that the automatic potentiometric titration method could meet the demand of detection sugar and could replace of the manual titration method.