TD NMR relaxation studies of cereal products

Abstract

In this chapter, an overview is given about the main time domain (TD) proton nuclear magnetic resonance (1H NMR) transversal relaxation studies on cereal products. Because of the scope of this book, first an introduction is given on changes of the main biopolymers during baking and storage of wheat bread, one of the most studied cereal products. TD 1 H NMR is an excellent technique to study the molecular mobility of water and biopolymers during processing and storage of cereal products including bread. Due to their complexity, starch-based model systems are often used to understand and interpret the complex NMR transversal relaxation time distributions of these products. Comparison of NMR relaxation data of the model systems and those of cereal products reveals that changes in proton mobility during processing and storage are largely caused by changes in the starch fraction, which is the main constituent of flour, and concomitant redistribution of water. Furthermore, a relationship exists between proton mobility on a molecular scale and the macroscopic textural properties of the food product, making TD 1 H NMR transversal relaxometry a very suitable technique to predict product quality.