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Two long grain and one medium grain brown rice varieties were gammairradiated at 1.0 and 2.0 kGy to ascertain if cooking time could be decreased and to determine effects of storage on chemical and physical characteristics. A tendency toward decreased cooking time was observed as dose level increased. Cooking time was not significantly (P~0.05) affected by storage. A trend was noted in water uptake ratios, soluble starch of residual cooking water and volume 'expansion due to irradiation. Storage of irradiated rice produced similar changes to those of nonirradiated rice. Variety also contributed to differences in irradiated samples, such as cooking times, water uptake, starch retention and grain volume expansion.

Brown rice samples prepared from medium grain (Mars) and long grain (Lemont and Tebonnet) varieties were irradiated at 0, 1.0, 2.0 and 3.0 kGy and analyzed. The amount of solids leached upon cooking increased with increased dose levels indicating the degradation of the rice grain structure. Damaged starch for Mars decreased to the 1.0 kGy level and increased thereafter. Moisture content remained constant between 13% and 14%. Amylose content was not greatly affected by irradiation. Peak viscosity, setback values, final viscosity, viscosity at SOY, and consistency all decreased with increasing levels of irradiation. As radiation increased, an increase in the yellow color of the rice samples was noted.

Quick-cooking rice was produced by soaking raw, white, long grain rice in a 1% aqueous sodium citrate and calcium chloride solution (5O:SO) at 50°C for 15 min. The soaked sample was cooked in an autoclave at 121°C for 3 min and freeze-dried to 20% moisture followed by convective air-drying to a final moisture of 12%.