Abstract
Water is an important component of nearly all food materials, and plays a decisive role in dictating the physical properties, quality and microbial, chemical and biochemical degradation of the food material [1]. For most food materials, unless the moisture content is reduced below 50% (wet basis), much of the water content is freely available to behave physically as pure water with properties such as vapor pressure equal to pure water. As moisture content is lowered further, a point will be reached at which the water becomes less active in that it cannot act physically or chemically as pure water. For example, it cannot freeze or act as a solvent or reactant. In this state, it is considered to be bound water.
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(2007). Water Activity. In: Food Physics. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-34194-9_1
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DOI: https://doi.org/10.1007/978-3-540-34194-9_1
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