Nuclear magnetic resonance studies of water mobility in bread during storage

The mobility of water in bread stored at 5 and 22°C was studied using nuclear magnetic resonance (NMR) relaxation techniques. A multi-component model was used to analyse the proton relaxation curves, from which water in the bread crumb samples was classified into three categories, each of which had a distinct relaxation time (T₂) or molecular mobility. The changes in crumb firmness, T₂ and proton intensity (A) of the three categories of water in the crumb were monitored during storage. It was found that several NMR parameters correlated with the firming process in the bread crumb (1), and could be related to macroscopic and microscopic migration of water during staling.