Choice of model gel systems for the food dehydration studies

Various solid model gel systems were prepared by using different compositions of agar, starch and microcrystalline cellulose. Model gel systems were air dried and their drying characteristics were defined in some visual terms (change in shape, shrinkage, occurrence of browning reaction, cracking, cross sectional view). Agar showed a high tendency to the shrinkage. Addition of starch decreased the rate of the shrinkage, however caused the cracking in solid model systems. The mixtures of agar, starch and microcrystalline cellulose in proper ratios showed better drying characteristics with their full, non-cracking structures and similar shrinkage characteristics to those of vegetables.