A Study on Mathematical Models for Predicting Water Activity in Multicomponent Foods

多成份食品水活性之預測模式

陳加忠(Chia-Chung Chen)

《中華農業研究》 39卷2期 (1990/06) Pp. 157-163

https://doi.org/10.29951/JARC.199006.0010

摘要

食品水活性的性質在混合、貯存、運輸等加工作業上十分之重要。此研究之目的即在於推導與驗證由多種成份混合製成食品的水活性預測模式。其應用之假設條件爲食品乾物質與所含水份的總質量不變，且在混合過程中無化學反應發生。利用等溫水份線的直線公式和史密斯公式，雖然可以直接求得預測值，但誤差偏大。利用非線性公式推衍所得的混合模式可以以數值方法求得預測值，其驗證結果則十分精確。

並列摘要

A model to predict water activity (equilibrium relative humidity/100) in multicomponent food mixtures is developed. It is based on balancing masses of water and dry matter and assumes that no interactions affecting water activity of the ingredients occur during mixing. Explicit solutions are presented for the linear and Smith forms of the isotherm equations. A numerical procedure is used to calculate the water activity for nonlinear isotherm equations. An example using data fro m the literature illustrates very good fittings by using appropriate isotherm equation for calculating of water activity of the mixture.