Evaluation of rice varieties for physicochemical characters related to puffing quality

Puffed rice is one of the convenient rice based popular products in India. Variability among varieties for important physicochemical characters of the grain like amylose, protein, gelatinization temperature, grain length breadth ratio, bulk density, expansion volume and expansion ratio affecting the puffing qualities were reported. The varieties with more length breadth ratio and high amylose will enhance the expansion ratio (ER) of puffed rice, whereas protein content shows a negative relationship with ER. Eight popular rice varieties viz., ADT 42, ASD 20, Bhavani, CO 43, INTAN, IR 64, MDU 6 and Paiyur 1 were analyzed for the physicochemical characters related to puffing quality. Based on the kernel length/breadth ratio, ADT 42, ASD 20, Bhavani, INTAN, IR 64, MDU 6 and Paiyur 1 were classified as long slender and CO 43 was identified as medium slender. The varieties Bhavani, INTAN, IR 64 and Paiyur 1 were classified as high amylose types (more than 25%) and ADT 42, ASD 20, CO 43 and MDU 6 as intermediate amylose types (20-20%) with regard to amylose. Bhavani, CO 43, Paiyur 1, INTAN and IR 64 had low protein content, while ADT 42 had highest protein content. The puffing yield ranged from 62.36% to 78.54% and higher values were recorded in Bhavani, INTAN, IR 64 and Paiyur 1. The association studies of physicochemical characters related to puffing quality revealed that puffing yield registered significantly positive correlation with starch content, amylose content, expansion volume and expansion ratio and negative correlation with protein and ash content. Amylose had negative association with protein and ash content. Out of eight varieties evaluated, Bhavani, IR 64, INTAN and Paiyur 1 had more length breadth ratio, high starch, high amylose and low protein which in turn resulted in high puffing yield. Hence, these varieties are highly suitable for making puffed rice.