Increasing oxidative stability in corn oils through extraction of γ-oryzanol from heat treated rice bran

Corn oil was mixed with heated rice bran with different extraction periods and ratios of rice bran to corn oil to extract gamma-oryzanol from rice bran. Selected corn oils based on the content of gamma-oryzanol were heated at 180 degrees C for 100 min or 60 degrees C for 16 days, and oxidative stability was evaluated. Corn oils recovered from the mixture of rice bran showed higher oxidative stability at both 60 and 180 degrees C treatment compared to control corn oils. At 180 degrees C, corn oils of a 1:5 ratio of rice bran to corn oil (w/w) showed higher oxidative stability than did those of 1:3 and 1:7 (w/w), whereas at 60 degrees C, corn oils of 1:7 (w/w) showed higher oxidative stability than did others. gamma-Oryzanol can be extracted through a corn-oil mixture at 80-90 mg/100 g oil, which is about 4.0% recovery of 2244 mg/100 g crude rice-bran oil. Oxidative stability of corn oils increased significantly, partly because of the extraction of gamma-oryzanol under current experimental conditions.