三油酸甘油酯/三硬脂酸甘油酯固体脂肪含量标准物质的研制及定值方法

Development and Determination of Reference Material for Glycerol Trioleate/Glycerol Tristearate Solid Fat Content

固体脂肪含量是描述可可脂、人造黄油等油脂的重要质量指标。低场核磁共振法由于具有简单、快速、无需化学试剂等优点,已逐渐成为测量固体脂肪含量的主流手段。低场核磁共振直接法是一种相对测量方法,需要使用三油酸甘油酯/三硬脂酸甘油酯混合物对仪器进行校准、溯源。本文介绍了低场核磁共振及测量固体脂肪含量的原理,研究了三油酸甘油酯/三硬脂酸甘油酯混合物的固体脂肪含量的定值溯源路径,研究了其在不同温度下的稳定性,分析了混合油管在不同温度条件下测量不准确的原因,并最终确定了标准物质的定值方法与温度。

Solid fat content(SFC) is an important quality indicator for describing fats and oils, such as cocoa butter and margarine. Low-field nuclear magnetic resonance(NMR) has become the mainstream method for measuring SFC due to its simplicity, speed, and lack of chemical reagents. The low-field NMR direct method is a relative measurement method that requires calibration and traceability of the instrument using a mixture of glycerol trioleate and glycerol tristearate. This paper introduces the principles of low-field NMR and SFC measurement, studies the traceability path of SFC for the glycerol trioleate/glycerol tristearate mixture, investigates its stability at different temperatures, analyzes the reasons for inaccurate measurement of mixed oil tubes at different temperature conditions, and finally determines the calibration method and temperature of the reference materials.