SACCHARIDES EXTRACTED FROM RICE GRAINS DU RING COOKING PROCESS AND EFFECT OF MONOGLYCERIDE ON THEM

The saccharides extracted from rice grains with and without monoglycer ide into aqueous layer during cooking process was investigated. Monogl yceride (0.5% of the rice) was added when the temperature of an electr ic rice cooker reached to 80 degrees C. The aqueous layer was separate d from rice by sieve at 0 min., 5 min. and 10 min. after the starting period. The aqueous layer was further separated to two fractions, supe rnatant and residue, by centrifugation (12 000 rpm). After 10 min. aqu eous layer could not be separated, because it was perfectly absorbed i nto rice grains. The results were as following; 1) Amounts of sacchari des in both fractions increased during cooking until 10 min. 2) The su pernatant of 0 min. contained sucrose and glycerol except glucosides. Glucose and maltose increased until 5 min. Amylose and dextrin increas ed until 10 min.. 3) The residue contained amylose and partially hydro lyzed amylopectin, and amounts of the both components increased until 10 min.. 4) Monoglyceride decreased amylose content in the residue of 10 min., but pretreatment of the residue with DMSO revealed that littl e difference exist in amylose content between the both residue with an d without monoglyceride. This observation suggested formation of amylo se-monoglyceride complex in the residue. This complex should be absorb ed again in the surface area of rice during cooking, hence the complex would significantly affect to physical properties of cooked rice.