Division of Genetics, Indian Agricultural Research Institute, Delhi-12
Twenty popular rice varieties collected from various parts of Northern India, including hill regions, were studied for chemical composition, cooking quality and protein content. Among the varieties from the plains, Basmati-370 is a superfine variety with high amylose content and good cooking quality, followed by Basmati-217, Desi Basmati, AC-3402 and AC-3404 in that order. All the hill varieties are similar in their cooking characteristics and would qualify as medium quality rices. The exotic varieties TN (1), Ashai and Norin-18 are very poor in appearance having short grains which stick on cooking. Protein content varied from 6*9 (in Norin 18) to 12-1 (T.N.-1). Lalnakanda, Basmati-217 and Jhona-20 have protein contents of 11.2, 10.2 and 10.1% respectively. The other varieties fall within the range of 7–10% of protein.
In general, the varieties grown in plains had a higher amylose content with better cooking quality. The amylose content of the hill varieties was less than that obtained for the varieties from plains and lowest values were recorded in exotic varieties. It was found that increase in amylose content was associated with an increase in the swelling number (b = 7.78). The length and breadth of the grain were obtained before and after cooking for all the varieties and those which showed increase in the L/B ratio were found to have good cooking quality. L/B ratio before cooking was positively associated with L/B ratio after cooking (b=0.93).
