ISO 16756:2024

Milk and milk products — Guidance for the application of Carr-Purcell-Meiboom-Gill (CPMG) pulsed time-domain nuclear magnetic resonance (TD-NMR) spectroscopy for fat determination

Scope

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.