Author(s): GO Ondier, TJ Siebenmorgen, A Mauromoustakos, GO Ondier, TJ Siebenmorgen, A Mauromoustakos
The effects of temperature and relative humidity (RH) on the equilibrium moisture contents (EMCs) of rough rice, brown rice, and head rice from non-parboiled pureline cultivars Wells (long-grain) and Jupiter (medium-grain), hybrid cultivar CL XL730 (long-grain), and a parboiled rice (long-grain) of unknown cultivar, were investigated. In addition, EMCs of broken kernels, bran, and hulls of Wells cultivar were investigated. Air conditions were maintained at temperatures of 50 °F to 140 °F, and RHs of 10% to °F, and RHs of 10% to F, and RHs of 10% to 70% to measure kernel-fraction moisture contents. Rice hulls attained the lowest EMC followed by rice bran, brown rice, broken kernels, and head rice; this held for both parboiled and non-parboiled samples. The Modified Henderson, Modified Chung-Pfost, Modified Halsey, Modified Oswin, and Modified Guggenheim-Anderson-DeBoer equations were evaluated to describe the sorption data of each kernel fraction. The Modified Chung-Pfost and Modified Guggenheim-Anderson-DeBoer equations were the most suitable for describing equilibrium data of rough rice, brown rice, broken kernels, and head rice of both parboiled and non-parboiled samples. The Modified Oswin equation was the most suitable for rice bran and hulls.