卡尔·费休库伦法测定三水合柠檬酸钙水分研究  

Determination of water content in calcium citrate trihydrate by Karl Fischer Coulometric method

作　　者：侯洋 薛峰[1,2] 彭亚锋[1,2] HOU Yang;XUE Feng;PENG Yafeng(Shanghai Institute of Quality Inspection and Technical Research,Shanghai 200233;National Food Quality Supervision and Inspection Center(Shanghai),Shanghai 200233)

机构地区：[1]上海市质量监督检验技术研究院,上海200233 [2]国家食品质量监督检验中心(上海),上海200233

出　　处：《中国食品添加剂》2022年第1期173-177,共5页China Food Additives

基　　金：国家重点研发计划课题“发酵乳制品核心技术及关键指标合格评定体系建立(2019YFF0217603)”。

摘　　要：目的:建立卡尔·费休库伦法测定三水合柠檬酸钙中的水分含量。方法:首先利用程序升温系统摸索出三水合柠檬酸钙的加热温度,然后在恒温条件下进行水分测试,确定样品水分检测时间。利用水标准物质进行加标回收,对两个不同批次的三水合柠檬酸钙样品进行精密度实验,并将两家实验室对两个批次同一样品的检测数据进行对比研究。结果:当加热温度为180℃时,三水合柠檬酸钙样品的结晶水全部检出,检测时间为30min。加标回收率达到99.6%~100.3%,回收率良好。两个不同批次的样品水分含量的相对平均偏差分别为0.27%和0.33%,结果精密度高。两家实验室的检测数据的相对平均偏差为0.16%~0.36%,精密度和重复性良好。结论:采用卡尔·费休库伦法测定三水合柠檬酸钙的水分含量,可以使样品中的游离水和结晶水完全检出,且精密性、重复性和稳定性良好,是测定其真实水分的有效方法。Objective:To establish a method for determination of water content in calcium citrate trihydrate.Methods:The best temperature for heating calcium citrate trihydrate was studied by using temperature program system.Then water content determination was conducted under the constant temperature.The recovery test was carried out by a water standard.Two different batches of calcium citrate trihydrate samples were tested and compared by two laboratories.Results:The crystal water of calcium citrate trihydrate can be detected completely at heating temperature of 180℃.The detection time was 30 minutes.The recoveries of water ranged from 99.6%to 100.3%.The relative average deviations of water content in two different batches were 0.27%and 0.33%,respectively.The data from two laboratories showed highly precise with the relative standard deviations of 0.16%~0.36%.Conclusion:The Karl Fischer Coulometric method can precisely determine the free water and the crystal water in calcium citrate trihydrate.The method has good reproducibility and stability and an effective way to detect water content in calcium citrate trihdrate.

关 键 词：三水合柠檬酸钙 卡尔·费休库伦法 结晶水 水分 

分 类 号：TS2[轻工技术与工程—食品科学与工程] Q948.112.3[生物学—植物学]