Rice bran oil
 A bottle of rice bran oil | |
| Fat composition | |
|---|---|
| Saturated fats | |
| Total saturated |
25% Myristic: 0.6% Palmitic: 21.5% Stearic: 2.9% |
| Unsaturated fats | |
| Total unsaturated | 75% |
| Monounsaturated | 38% |
| Oleic acid | 38% |
| Polyunsaturated | 37% |
| Omega-3 fatty acids | α-Linolenic: 2.2% |
| Omega-6 fatty acids | Linoleic: 34.4% |
| Properties | |
| Food energy per 100 g (3.5 oz) | 3,700 kJ (880 kcal) |
| Smoke point | 232 °C (450 °F) |
| Iodine value | 99-108 |
| Acid value | 1.2 |
| Saponification value | 180-190 |
| Unsaponifiable | 3-5 |
Rice bran oil is the oil extracted from the hard outer brown layer of rice called chaff (rice husk). It is known for its high smoke point of 232 °C (450 °F) and mild flavor, making it suitable for high-temperature cooking methods such as stir frying and deep frying. It is popular as a cooking oil in several Asian countries, including Bangladesh, Japan, India, and China.[1]
Uses
Rice bran oil is an edible oil which is used in the preparation of vegetable ghee. Rice bran wax, obtained from rice bran oil and palpanese extract, is used as a substitute for carnauba wax in cosmetics, confectionery, shoe creams, and polishing compounds.
Composition
Rice bran oil has a composition similar to that of peanut oil, with 38% monounsaturated, 37% polyunsaturated, and 25% saturated fatty acids. The fatty acid composition is:[1]
| Fatty acid | Percentage |
|---|---|
| C14:0 Myristic acid | 0.6% |
| C16:0 Palmitic acid | 21.5% |
| C18:0 Stearic acid | 2.9% |
| C18:1 Oleic acid (an Omega 9 fatty acid) | 38.4% |
| C18:2 Linoleic acid (LA, an Omega 6 fatty acid) | 34.4% |
| C18:3 α-Linolenic acid (ALA, an Omega 3 fatty acid) | 2.2% |
Physical properties of crude and refined rice bran oil[2][3]
| character | Crude Rice bran oil | Refined oil |
| Moisture | 0.5-1.0% | 0.1-0.15% |
| Density (15-15 °C) | 0.913-0.920 | 0.913-0.920 |
| Refractive Index | 1.4672 | 1.4672 |
| Iodine value | 85-100 | 95-104 |
| Saponification value | 187 | 187 |
| Unsaponifiable matter | 4.5-5.5 | 1.8-2.5 |
| Free fatty acids | 5-15% | 0.15-0.2% |
| oryzanol | 2.0 | 1.5-1.8 |
| Tocopherol | 0.15 | 0.05 |
| Color(Tintometer) | 20Y+2.8R | 10Y+1.0R |
Health benefits
A 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, together as vitamin E. Rice bran oil is also rich in other phytosterols.
Isolated Γ-oryzanol (Chinese: 谷维素) is available in China as an over-the-counter drug,[4] and in other countries as a dietary supplement.
Cholesterol
Literature review shows rice bran oil and its active constituents improve blood cholesterol by reducing total plasma cholesterol and triglycerides, and increasing the proportion of HDL cholesterol.[5] Results of an animal study[6] indicated a 42% decrease in total cholesterol with a 62% drop in LDL cholesterol, when researchers supplemented test subjects' diets with fractionated vitamin E obtained from rice bran oil.
Menopause
One small-scale study of γ-oryzanol, a mixture of chemicals found in rice bran oil, found that 90% of the women had some form of relief from hot flashes during Menopause after taking a supplement of the purified concentrate for four to six weeks.[7]
Antioxidant stability
The oryzanol content of the pan heated rice bran oil samples remains approximately the same even when heated at 180 ˚C for 8 hours, while a decrease in oryzanol content was reported in the case of microwave heating at the same conditions.[8]
Calcium absorption
Rice bran might help lower cholesterol because the oil it contains has substances that might decrease cholesterol absorption and increase cholesterol elimination. One of the substances in rice bran might decrease calcium absorption. This might help reduce the formation of certain types of kidney stones.[9]
Insulin resistance
In utero exposure to germinated brown rice and its oryzanol-rich extract attenuated high fat diet-induced insulin resistance in rats. [10]
See also
References
- 1 2 3 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. Retrieved 2012-03-01.
- ↑ http://www.riceactive.com/?page_id=203
- ↑ SEA HandBook-2009, By The Solvent Extractors'Association of India
- ↑ "National Drug Standard for 谷维素片 / Oryzanol Tablets (DRAFT)" (PDF). 国家食品药品监督管理总局. Archived from the original (PDF) on 29 July 2018. Retrieved 29 July 2018.
- ↑ 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. Retrieved 2006-10-09.
- ↑ Minhajuddin, M; Beg, ZH; Iqbal, J (2005). "Hypolipidemic and antioxidant properties of tocotrienol rich fraction isolated from rice bran oil in experimentally induced hyperlipidemic rats". Food and Chemical Toxicology. 43 (5): 747–53. doi:10.1016/j.fct.2005.01.015.
- ↑ 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.
- ↑ Paul, A.; Masih, D., Masih, J., Malik, P. (2012). "COMPARATIVE ANALYSIS OF HEAT DEGRADATION OF ORYZANOL IN RICE BRAN OIL, MUSTARD OIL AND SUNFLOWER OIL BY MICROWAVE AND PAN HEATING" (PDF). International Journal of Food and Nutritional Sciences. 1 (1): 110–117. Retrieved December 2012. Check date values in:
|accessdate=(help) - ↑ http://www.webmd.com/vitamins-supplements/ingredientmono-852-rice%20bran.aspx?activeingredientid=852&activeingredientname=rice%20bran
- ↑ Hadiza, Altine .; Mustapha Umar Imam, Der-Jiun Ooi, Norhaizan Mohd Esa, Rozita Rosli (2017). "In utero exposure to germinated brown rice and its oryzanol-rich extract attenuated high fat diet-induced insulin resistance in F1 generation of rats" (PDF). BMC Complementary and Alternative Medicine. 17: 67. doi:10.1186/s12906-017-1571-0. PMC 5251246. PMID 28109299. Retrieved January 2017. Check date values in:
|accessdate=(help)