Rice bran oil

Rice bran oil (also known as rice bran extract) is the oil extracted from the germ and inner husk of rice. It is notable for its high smoke point of 213 °C (415 °F) and its mild flavor, making it suitable for high-temperature cooking methods such as stir frying and deep frying.^[1] It is popular as a cooking oil in several Asian countries, including Japan and China.^{[2][verification needed]}

Uses

Rice bran wax, obtained from rice bran oil, is used as a substitute for Carnauba wax in shoe creams and polishes.

Composition

Rice bran oil has a composition similar to that of peanut oil, with 38% monounsaturated, 37% polyunsaturated, and 25% saturated. The fatty acid composition is:^[1]

Health benefits

A medically significant component of rice bran oil is the antioxidant γ-oryzanol, at around 2% of crude oil content. Thought to be a single compound when initially isolated, it is now known to be a mixture of steryl and other triterpenyl esters of ferulic acids.^[1] Also significant is the relatively high fractions of tocopherols and tocotrienols, taken together as vitamin E. Rice bran oil is also rich in other phytosterols which may provide health benefits.

Cholesterol

Literature review shows that rice bran oil and its active constituents improve blood cholesterol by reducing total plasma cholesterol and triglyceride , and increasing the proportion of HDL cholesterol.^[3] Results of an animal study^[4] indicated a 42 percent decrease in total cholesterol with a 62 percent drop in LDL cholesterol, when researchers supplemented test subjects' diets with fractionated vitamin E obtained from rice bran oil.

Menopause

The rice bran oil component γ-oryzanol was shown in Japan to be effective in relieving hot flashes and other symptoms of female menopause. Researchers found that 90% of the women found some form of relief from hot flashes after taking a rice bran oil supplement for 4–6 weeks.^[5]

Antioxidant stability

Studies have shown that the antioxidant stability in rice bran oil remains almost constant even when heated at frying temperatures. The study of thermal degradation and antioxidant stability in the oil is carried out by heating the oil to the frying temperature up to 250°C for 0.5, 1, 1.5, 2hrs. The density of rice bran oil is found to be constant throughout the time of heating illustrates there is no molecular changes due to antioxidant activity in the oil. The oxidative stability of rice bran oil was equivalent to or better than soybean, corn canola, cottonseed, and safflower oil in a model system that simulated deep frying conditions.^[6])

Other benefits

Other potential properties of rice bran oil include modulation of pituitary secretion, inhibition of gastric acid secretion, antioxidant action and inhibition of platelet aggregation. ^[3]

See also

• Cereal germ
• Oat bran oil
• Rice germ oil
• Wheat germ oil
• Wheat bran oil

References

1. ^ ^{a b c} Orthoefer, F. T. (2005). "Chapter 10: Rice Bran Oil". In Shahidi, F.. Bailey's Industrial Oil and Fat Products. 2 (6 ed.). John Wiley & Sons, Inc.. p. 465. ISBN 978-0-471-38552-3. http://books.google.com/books?id=wG-0QgAACAAJ. Retrieved 2012-03-01. 
2. ^ California Rice Oil Company. "Health Benefits of Rice Bran Oil". http://www.californiariceoil.com/healthbenefits.htm. Retrieved 2006-10-09. ^{[Third-party source needed]}
3. ^ ^{a b} A.F. Cicero, A. Gaddi (2001). "Rice bran oil and gamma-oryzanol in the treatment of hyperlipoproteinaemias and other conditions". Phytother Res 15 (4): 277–286. DOI:10.1002/ptr.907. PMID 11406848. http://www.findarticles.com/p/articles/mi_m0FDN/is_5_6/ai_80490897. Retrieved 2006-10-09. 
4. ^ Minhajuddin M, Beg ZH, Iqbal J. "Hypolipidemic and antioxidant properties of tocotrienol rich fraction isolated from rice bran oil in experimentally induced hyperlipidemic rats." Food and chemical toxicology. 2005; 43(5):747-53.
5. ^ Ishihara, M; Ito, Y; Nakakita, T; Maehama, T; Hieda, S; Yamamoto, K; Ueno, N (1982). "gamma-oryzanol on climacteric disturbance". Nihon Sanka Fujinka Gakkai zasshi 34 (2): 243–51. PMID 7061906. 
6. ^ http://www.rasayanjournal.com+(2006-10-09). "Antioxidant stability in palm and rice bran oil using simple parameters". Science Daily. http://rasayanjournal.com/View-document/322-ANTIOXIDANT-STABILITY-IN-PALM-AND-RICE-BRAN-OIL-USING-SIMPLE-PARAMETERS.html. Retrieved 2011-06-09.