Cereal Chem 51:336 - 344.  |  VIEW ARTICLE
Calorimetric Studies on Swelling of Rice. I. Swelling of Rice Grain and Rice Powder.

T. Kanemitsu and K. Miyagawa. Copyright 1974 by the American Association of Cereal Chemists, Inc. 

Heats of swelling of rice kernel (white rice) and rice powder were measured at 30 C. Rice kernel with about 14% moisture content evolves heat of 1.6 to 2.1 cal. per g. rice with swelling. Degree of polishing of rice has no effect on water absorption and heat of swelling. Heat of swelling of rice powder is a little larger than that of rice kernel and the finer the powder, the greater the heat of swelling. Calorimetrically, swelling of rice powder follows the first-order reaction, but swelling of rice kernel does not. That is, the plotting of first-order reaction of swelling of rice kernel is not straight-line but twofold. The reaction velocity constant, k, of the first-order reaction, increases with the diameter of the powder particle and k also is proportional to the total surface area of the powdered grain.