MOISTURE SORPTION CHARACTERISTICS OF COMPOSITE FOODS FILLED WITH STRAWBERRY JAM

Moisture sorption isotherms (MSIs) of cracker cookie, jam (strawberry jam), and two types of composite food [CF1 (cracker/jam/cracker) and C F2 (cookie/jam/cookie)] were determined at 20-40 degrees C and 11-85% relative humidity. The MSIs were fitted into the Guggenheim-Anderson-d e Beer (GAB) equation and their temperature dependence was evaluated b y rise of the temperature-dependent GAB parameters. Jam had the highes t mono-layer (m(o)) value and equilibrium moisture content (EMC), foll owed by cracker and cookie. The m(o) or EMC values of composite snack foods depended on those values of crust (cracker or cookie) and fillin g (jam). The MSIs of the composites lie between those of crust (cracke r 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, w hile C-2 values increased with temperature. Jam had the highest sorpti on energy levels, followed by cracker and cookie. CF1 showed higher so rption energy levels than CF2 at moisture contents of 0.03 kg water/kg solid oi higher. (C) 1998 Academic Press.