MSc

A study was conducted on the “Quality parameters of popular rice varieties”. The study was based on the assessment of the nutritional composition, physical characteristics, cooking characteristics and organoleptic qualities as influenced by different processing methods. The effect of different cooking methods on the nutritional composition was also assessed.

The results of the analysis showed that all the nutrients studied were found to be higher in the high yielding rice varieties evolved by KAU when compared to the local varieties studied. Among the nutrients analysed the calorific value, iron content and ash content were found to be increased as a result of parboiling , while all other nutrients experienced a loss. Protein, calcium and iron were experiencing an increase as a result of puffing.

The physical characteristics studied showed that the local varieties were having a higher value for thousand grain weight and moisture content, while the grain dimensions, head rice yield and gelatinization temperature were found to be higher in the high yielding varieties evolved by KAU. As a result of parboiling all the physical characteristics except moisture content and grain dimension ratio were found to be increased.

The cooking characteristics studied revealed that there was not much difference in the optimum cooking time, water uptake, volume of expansion and total amylose between the local as well as evolved varieties. But the elongation ratio and elongation index was found to be higher in the high yielding varieties of rice evolved by KAU. A decrease in all the cooking characteristics except optimum cooking time and elongation index was observed as a result of parboiling.

The organoleptic qualities of the different rice varieties showed a marked preference for the local varieties in all the six quality attributes studied. Among the six quality attributes, appearance flavor and taste were found to obtain a higher mean score as a result of parboiling.

The results of the effect of different methods of cooking on the nutritional composition showed that all the nutrients studied were experiencing a loss when boiled and retained more when roasted. The protein, calcium and phosphorus contents were found to be decreased as result of parboiling after cooking, while the iron content was increased. Roasting and frying in a cast iron pan was found to increase the iron content. In general the high yielding varieties of rice evolved by KAU were found to contain higher amounts of all the nutrients studied when compared to the local varieties after cooking.

The results of correlation analysis revealed that the nutritional composition of rice varieties were not determined by the physical characteristics of the grains. The nutritional composition did not influence the cooking quality either. The physical characteristics of rice grains were found to have profound influence on the cooking quality of rice. Most of the cooking qualities studied were inter related. The ultimate acceptability of a rice variety after it was cooked, was not influenced by neither the physical features nor the cooking qualities.

The results of the study enables one to conclude that the high yielding rice varieties evolved by KAU when compared to local varieties have better nutritional composition , though to taste panels on the basis of organoleptic qualities local varieties were more preferred. Cooking qualities and physical characteristics were also on the advantageous side for the evolved varieties.