Moisture Sorption Characteristics of Composite Foods Filled with Strawberry Jam

Abstract Moisture sorption isotherms (MSIs) of cracker, cookie, jam (strawberry jam), and two types of composite food [CF1 (cracker/jam/cracker) and CF2 (cookie/jam/cookie)] were determined at 20–40 °C and 11–85% relative humidity. The MSIs were fitted into the Guggenheim–Anderson–de Boer (GAB) equation and their temperature dependence was evaluated by use of the temperature-dependent GAB parameters. Jam had the highest mono-layer (m o ) value and equilibrium moisture content (EMC), followed by cracker and cookie. The m o or EMC values of composite snack foods depended on those values of crust (cracker or cookie) and filling (jam). The MSIs of the composites lie between those of crust (cracker or cookie) and filling (jam). The CF1 had higher EMC values than the CF2. The GAB m o values and C 1 values decreased with temperature, while C 2 values increased with temperature. Jam had the highest sorption energy levels, followed by cracker and cookie. CF1 showed higher sorption energy levels than CF2 at moisture contents of 0.03 kg water/kg solid or higher.