Study On Rice-Cooking And Rice Eating-Test

The intention of this experiment was,by studying on rice-cooking and eating-test of different rice varieties,to search for the factors influencing rice cooking and eating quality and probed into the optimal technique of rice-cooking.The results showed as follows:(l)Before cooking rice,washing quickly was necessary to eliminate the impurities on the surface of rice grains,then,to make rice grains drink plenitudinously and equally,soaking in proportional water was needed.In the end of heating, heat preservation for 15~30min was conducted to make starch paste completely and equally. At this point,the eating-quality of cooked-rice was the best.(2)According to the temperature change in boiler and the amount of water absorbed during cooking,the course of cooking could be divided into three periods :heating with strong fire,boiling away and heat preservation. The temperature change in boiler related to degree of heating and quantity of rice.Amylum composition influenced the amount of water rice grains absorbed during cooking.The more the amylose, the more the water. Whereas,the more the amylopectin,the less the water.(3) Conformation of grains during cooking showed that amylum pasted from outside to inside,and the good taste rice and its transverse section had better transparency and polish than the poor.(4)With regard to soluble sugar,there was not evident change before and after cooking.But during cooking process,because of dissolving in water,its content decreased.(5)The content and compose of amylum and protein was the main factor influencing rice cooking and eating quality. The result of eating-test showed clearly that higher amylose content or higher protein content should lower rice cooking and eating quality.(6)Cooking and eating quality of rice changed with its storage after harvest.The extent was various with the quality before storage.The better the quality before storage was,the less extent stored rice quality decreased.(7)Cooking colored rice needed a longer soaking-time and cooking-time,and the eating-quality of cooked-rice was very poor. But if polished before cooking,its nutrition characteristic and feature should be losed.So,in order to prevent this loss and not to influence rice cooking and eating-quality,colored rice would be used to cook porridge but not cook rice directly.(8)Chalk would make rice appearance quality inferior and hinder water absorbed,but couldn't affect rice paste characteristic and rice eating quality.