Sorption isotherms of food materials above 100°C

Abstract

Desorption isotherms and isobars are presented for microcrystalline cellulose (MCC), potato starch, cake dough and lactose measured at temperatures between 100 and 140°C using a manometric and dynamic sorption method. From nine mathematical models which have been transformed to take into account the effect of temperature and pressure, Oswin’ modified model seems to be the best to fit the experimental data. Isosteric heat was calculated in this field of temperature, for MCC, potato starch, and cake dough using the Clausius-Clapeyron equation. The effect of temperature on isosteric heat is negligible compared to that of moisture content. © 1993 Academic Press, Inc.