抄録
Solution thermodynamics was applied to the water sorption isotherms of foods. First, we corrected Le Maguer's theory. By this correction, it was found that the same thermodynamic equations were applicable to both water sorption data measured at constant total pressure (P) and to those measured under the particular vapor pressure, P = Pw, for a food material. Second, the change in the water sorption behavior of rice flour by defatting and extrusion cooking was analyzed by solution thermodynamics. It was confirmed that the principle of solution thermodynamics is more appropriate than that of conventional adsorption thermodynamics for evaluating the affinity of food for water. The enhanced affinity of rice flour for water by defatting and extrusion was quantitatively evaluated by solution thermodynamics.
