电位滴定法测定槟榔中总酸的不确定度评定

Evaluation of Uncertainty in Determination of Total Acid in Areca Nut by Potentiometric Titration

对电位滴定法测定槟榔中总酸含量进行不确定度评定。建立影响槟榔中总酸含量的数学模型,并对电位滴定法测量槟榔中总酸的不确定度进行评定。样品槟榔中总酸含量为6.67 g/kg (以苹果酸计)时,测定结果的扩展不确定度为0.160 g/kg。GB/T 12456—2008 《食品中总酸的测定》标准方法测定槟榔中总酸不确定度的最主要来源是试样消耗氢氧化钠标准滴定溶液体积引入的不确定度,因此在试验过程中应该严格控制滴定终点,确保试验结果准确可靠。

The uncertainty of the total acid content in betel nut was determined by potentiometric titration.A mathematical model was established to influence the total acid content in areca nut,and the uncertainty of total acid in betel nut was measured by potentiometric titration.When the total acid content of the betel nut was 6.67 g/kg,the expansion uncertainty was 0.160 g/kg.The main method for determining the uncertainty of total acid in betel nut by GB/T 12456-2008“Determination of total acid in food”was the uncertainty introduced by the sample volume of sodium hydroxide standard titration solution,so in the experimental process.The titration end point should be strictly controlled to ensure accurate and reliable experimental results.