Effect of Paddy Parboiling and Rice Puffing on Physical, Optical and Aerodynamic Characteristics

Rice (Oryza sativa L) is the second largest important cultivated cereal. India is among major rice producing countries in world and Asia contributed 90 percent of the world cultivated area. India contributes more than 20% of paddy production in world with a figure of 152.6 MMT in 2012. Rice being invaluable alternative source of carbohydrate being easily digestible and has rare allergic reactions. Puffed rice is a whole-grain puffed product obtained from pregelatinized milled parboiled rice. This changed form of rice starch in resistant starch may be nutritionally important fraction as dietary starch, which may thus escapes unaffected during digestion and absorption in the small intestine. Also if it goes to large intestine in unaffected form may serve as nutrient for the gut micro-flora. The roasted form of rice as puffed rice may thus also be considered as prebiotic foods apart from the conventional and nutritious low cost easily reach food to masses. Therefore, attempts have made for the preparation of puffed rice from the use of commercially important medium slender paddy genotype, Gurjari as raw material in our study. As per the result the expansion ratio was found in the range of 2.08 to 2.43 in the dimensional parameters. The increase in the surface area was found to be 5.01times that of the raw rice leaving the aspect ratio and sphericity unaltered, which is the indicator that the rice is puffed in all the dimension uniformly. The other physical properties found were in consistent with our earlier studies. The puffed rice has showed lighter optical colour with Lab value as 76.33, 0.66 and 0.33. The terminal velocity under the study of aerodynamic property showed, puffed rice could float with a very low air flow rate of 0.78 ms. S. Kumar & K. Prasad 766