Rice bran oil

About: Rice bran oil is a research topic. Over the lifetime, 2102 publications have been published within this topic receiving 32504 citations.

Refining Of Rice Bran Oil (oryza Sativa L.) To Preserve γ-orizanol [refino De óleo De Farelo De Arroz (oryza Sativa L.) Em Condições Brandas Para Preservação Do γ-orizanol]

Abstract: γ-orizanol is an antioxidant present in rice bran oil, but absent in other vegetable oils, which were attributed to antioxidant and hypocholesterolemic effects. The content of γ-orizanol in crude rice bran oil varies between 1-2%, but during neutralization in chemical refining this substance is transferred to soapstock. The aim of this research is to study an alternative technique of physical refining in light conditions with the purpose of preserving γ-orizanol. Inativacted and extrused rice bran obtained by the production of parboilizated rice was used to extract crude rice bran oil (Oryza sativa) by the expeller method. The process of refining consisted of: acid degumming (with 85% H3PO4), centrifugation, clarification, deodorization, and winterization. Chemical analyses were carried out by the characterization of refined oil according to the AOCS methods. Results showed that the physical refining process was able to preserve 97% of γ-orizanol, and its presence improved the oxidative stability of the oil comparing with the commercial rice bran oil (by 33% 13.3 hours to 110 oC).

Thermal oxidation of rice bran oil during oven test and microwave heating

Abstract: The purpose of the present study was to evaluate the oxidative stability of physically refined rice bran oil (RBO) under oven heating at 63 °C and microwave heating conditions by absorptivity. Oil samples with tertiary-butylhydroquinone (TBHQ) (100 ppm and 200 ppm), citric acid (CA), butylhydroxyanisole/butylhydroxytoluene (BHA/BHT) and in other combination, BHA/BHT+CA were submitted to oven test for 6 days, and the linear coefficient of correlation between peroxide value and absorptivity at 232 nm was determined. The gradual increase in peroxide value and absorptivity at 232 nm was observed in all the RBO samples, control and antioxidant added. RBO samples added with tertiary-butylhydroquinone (TBHQ) had shown the least peroxide value and absorptivity as 6.10 and 5.8 respectively, when added at a concentration of 200 ppm whereas; the control RBO samples had shown the maximum values. The peroxide values obtained from the correlations during the oven test were found closely correlated with the peroxide values obtained during the microwave oven heating experimentally. The effect of microwave heating on the oryzanol content and p-anisidine value was also observed and the correlation to the oven test was established. The oryzanol content and p-anisidine values obtained after oven heating when correlated to the microwave heating data showed the oryzanol content 13,371, 13,267 and 13,188 ppm after 1 day, 4 days and 5 days respectively which were closely correlated with the experimental value.

Comparison of 11 rice bran stabilization methods by analyzing lipase activities

Abstract: The production of rice bran oil is severely impeded because of the rapid rancidity caused by rice bran lipase. Eleven stabilization treatments including 6 heating treatments and 5 nonheating treatments were carried out in this research. Lipase activities as well as oil colors, oil compositions, and contents of vitamin E and γ‐oryzanol after different treatments were investigated to evaluate the effect of stabilization and oil qualities. All the treatments had no significant influence (p > .05) on the oil compositions and γ‐oryzanol contents. Among six heating treatments, autoclaving had the best stabilization effect for 10.73% lipase activity remained and other heating treatments held about 30%–35% lipase activities residual except dry heating (68.88%). Heating treatments except steam heating resulted in the significant decreases (p .05) on oil acid values and color. In conclusion, ultraviolet irradiation might be a potential, convenient, and energy‐saving stabilization method with high oil quality. PRACTICAL APPLICATIONS: Rice bran has a potential for producing about 8 million tons of rice bran oil worldwide but nearly 90% rice bran was wasted every year. The processing of rice bran is impeded because of the rancidity caused by lipase, so the stabilization of rice bran is very important. This research provided a new and time‐saving method for evaluating stabilization efficacy instead of long time storage. Using this new evaluating method, 11 stabilization methods were compared and methods like microwave, extrusion, and ultraviolet irradiation were considered to be suitable methods for industrial processing. In additional, ultraviolet irradiation was found to be a potential, convenient, and energy‐saving stabilization method without influencing oil quality and nutrient content.

Supercritical CO2 Extraction of Rice Bran Oil -the Technology, Manufacture, and Applications.

Abstract: Rice bran is a good source of nutrients that have large amounts of phytochemicals and antioxidants. Conventional rice bran oil production requires many processes that may deteriorate and degrade these valuable substances. Supercritical CO2 extraction is a green alternative method for producing rice bran oil. This work reviews production of rice bran oil by supercritical carbon dioxide (SC-CO2) extraction. In addition, the usefulness and advantages of SC-CO2 extracted rice bran oil for edible oil and health purpose is also described.