Applications of Low-Field Pulsed Nuclear Magnetic Resonance Technique in Lipid and Food

The ratio between liquid and solid portion of lipid can be determined quickly and accurately by low-field pulsed nuclear magnetic resonance (LFP-NMR) instrument. This analytical tool has become one of important techniques to characterize product physical properties especially related to fat melting behavior, mouth feeling, and cooling effect etc. in lipid and food application system. In lipid, it can be used to determine the solid fat content, evaluate the crystallization rate and the compatibility of lipid blends, monitor the enzymatic interesterification degree, and estimate the fat crystal type. As a nondestructive testing, LFP-NMR technique was also applied to analyze the particle size distribution of emulsion, the fat crystallization, and the quality control during food storage. LFP-NMR is not only applied to evaluate the fat crystallization, but also to analyze the crystallinity of sugar. These application progresses of LFP-NMR technique in lipid and food will be summarized in this chapter.

Keywords: Compatibility, crystallinity, crystallization rate, emulsion, foods, interesterification, lipids, low-filed pulsed NMR, particle size distribution, polymorphism, SFC.