乳制品——关于Carr-Purcell-Meiboom-Gill(CPMG)脉冲时域核磁共振(TD-NMR)光谱法测定脂肪的指南

[中文适用范围]： 本文件提供了关于使用Carr-Purcell-Meiboom-Gill(CPMG)脉冲序列优化分子特定响应的低分辨率核磁共振光谱法测定乳制品中脂肪总量的指导。 [外文原描述]： This document gives guidance on the determination of total fat content in milk and milk-based products, such as milk, cream, yogurt, ice cream, processed dairy, cheese and dairy powders by low-resolution nuclear magnetic resonance (NMR) using Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence to optimize the specific response of fat molecules. This document is applicable to the analysis of any milk and milk-based products, regardless of source (species or region). It is applicable to dry samples (i.e. moisture content ≤ 10 %) and liquid or wet samples which have been pre-dried such that all appreciable water has been removed. The NMR with CPMG pulse sequence analyses glycerolipids, which produces fat results comparable to the total fat result of standard fat extraction techniques, without the need for matrix specific calibrations while meeting the precision criteria listed in Clause 12. The application is not limited by sample viscosity, colour or particle size.