First approach on rice bran oil extraction using limonene

Edible oil extraction with petroleum derivatives as solvents has caused safety, health, and environmental concerns everywhere. Thus, finding a safe alternative solvent will have a strong and positive impact on environments and general health of the world population, considering the scale of oil extraction operations worldwide. T he extraction of oil from rice bran by d-limonene and hexane (for comparison) has been carried out at their respective boiling points at various solvent-to-meal ratios and for various extraction times. The preliminary data suggested that the optimum solvent-to-meal ratio and extraction time required for d-limonene extraction of rice bran oil to be 5:1 and 1 h respectively. The initial quality characteristics (free fatty acid content, oil color, phospholipid content) of crude oil extracted under these optimum conditions were analyzed using various analytical methods based on the standard methods of AOCS and were found to be comparable to the oil extracted with hexane. The initial positive result has paved the way for further studies on issues related to meal qualities as well as to a scale-up of the method in the near future.