Abstract
The operating parameters which are controlled in order to achieve the optimal evolution of a fermentation process are usually: temperature, pH, aeration, nutrients concentration. Hydration characteristics of the fermentation medium are considered only very rarely, although they are recognized as important parameters of microbial growth and activity. Water activity (aw) is an essential parameter in the hurdle technology concept (Leistner et al. 1981) which proved its efficiency as regard the microbial stability of foods. The value of the aw parameter, however, is being discussed. It was recently claimed that its use should be replaced in the field of food technology by a better consideration of the specific effects of the solutes used to depress aw (Franks 1985), or by parameters connected with the plastifying properties of water (Slade and Levine 1985).
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© 1989 Kluwer Academic Publishers
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Simatos, D., Gervais, P. (1989). Importance and Feasibility of Modeling and Controlling Hydration Properties in Fermentation Processes. In: Singh, R.P., Medina, A.G. (eds) Food Properties and Computer-Aided Engineering of Food Processing Systems. NATO ASI Series, vol 168. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-2370-6_17
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DOI: https://doi.org/10.1007/978-94-009-2370-6_17
Publisher Name: Springer, Dordrecht
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