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

Autor: Elena Vittadini, Pavinee Chinachoti, Xuyen Pham, James P. Lavoie
Rok vydání: 2005
Předmět:
Zdroj: Innovative Food Science & Emerging Technologies. 6:21-28
ISSN: 1466-8564
DOI: 10.1016/j.ifset.2004.11.001
Popis: The role played by water activity (aw), “mobility” (“molecular” by Nuclear Magnetic Resonance (NMR) analysis and “macromolecular”, by glassy to rubbery transition, thermal analysis) and physico-chemical properties of the media in modulating microbial response have been studied in multicomponent model food systems of different physical state. NMR “molecular” mobility correlated well with microbial (mold spore) response in solid and semisolid systems (dry and intermediate moisture foods) while in high moisture, liquid, homogeneous systems water activity was found to correlate better with Staphylococcus aureus activity. Correlation between microbial survival ability and glassy to rubbery transition in heterogeneous and complex model systems is not yet conclusive. Industrial relevance 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.
Databáze: OpenAIRE