Correlation of microbial response in model food systems with physico-chemical and “mobility” descriptors of the media

Food technologists, in order to assure safety and stability of food products, should understand the relevant factors in microbial activity. Water availability is a fundamental principle in food preservation and it might be related to water mobility. Mold spoilage, has been shown to be closely related to water mobility (in this case, measured by NMR). However, in some systems, when humectants are used, water activity is an important empirical parameter in food preservation involving intermediate moisture foods. In this work, the role played by “mobility” (“molecular” by NMR analysis and “macromolecular”, by glassy to rubbery transition, thermal analysis) was analyzed in food model systems and an important role of “water mobility” was suggested.