Comparison of rice bran oil and wax yields; a systematic approach to wax ester analysis

Rice bran oil (RBO) comprises 2–4% of rice bran wax (RBW) which contains wax esters (WE), hydrocarbons and other minor constituents, and there is still a lack of information on the RBW yields by various extraction methods and the WE contents in RBW. In this study, the yields of RBO and RBW extracted with Soxhlet and microwave‐assisted extraction (MAE) were compared with establish suitable RBW preparation methods. HPLC methods were also developed to determine the WE contents in RBW. MAE with hexane was the most efficient method for higher RBW yields as well as higher WE contents. The HPLC analysis proved that around half of the refined RBW consists of WE. The results established an efficient procedure for RBW preparation, which includes MAE with hexane, RBO refinement, winterisation, solvent fractionation and HPLC separation.