Studies on Particle Size Distribution of Rice Bran Wax in the Presence of Gum and Oil in Hexane Medium

Abstract

Particle size distribution of rice bran wax crystals formed during cooling in hexane medium has been investigated by dynamic light scattering technique. Solutions of wax (1 g), gum–wax (1:1) in food-grade n-hexane (100 ml), gum–wax–physically refined rice bran oil (PRBO) (1:1:30 by weight) in hexane (70 ml) and rice bran oil (RBO)–hexane miscella (RBOM) were crystallized at various temperatures of 5–40 °C range. Crystallization of gum and wax, incubation time and temperature, inhibition in crystal growth in the presence of gum and triglyceride of PRBO and crude RBOM have been investigated. Temperature range of 5–12 °C for high gum content oil and 40–60-min incubation time have been optimized for effective fractionation of gum and wax from oil–hexane miscella to get higher centrifugation mass yield with better purity. The presence of gum and wax in 1:1 ratio has been shown to produce a maximal number of smaller-sized wax crystals at 15 °C.