Studies on the Heat Inflation of Dried Starch Paste

Part I. The appropriate method for the evaluation of heat inflation

Abstract

For basic studies on heat inflation of dried starch paste, methods for preparation, drying and heat inflation of starch paste were examined.
The appropriate method examined was as follows:
1. Preparation of starch paste starch sluries(20g of potato starch, water with 1.5 times of dry starch) in hi-zex film were pre-gelatinized at 70-80°C, pressed to about 2mm in thickness, and heated in boiling water bath for 5min after heat sealing. Immediately, the paste was pressed to 2mm in thickness again, stored over night at 20°C, cutted to piece 14mm in diameter, was dried at 45°C for 4hr, and kept at 30°C for about a month in 80% relative humidity.
2. Heat inflation of dried paste; the paste was inflated by two infrared lamps for 30 sec with controlling the surface temperature from 100 to 170°C, or by flying by oil at 180°C.
3. Evaluation of inflation: the volume and hardness of product was measured by Seed-substitution methods and Autograph, respectively.