Rice bran oil

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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 after chaff ( rice husk). It is notable for its high smoke point of 232 °C (450 °F) and its 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 Japan and China.[1]

A bottle of rice bran oil, flanked by smaller bottles of sesame oil and hemp seed oil.

Uses[edit]

Rice bran wax, obtained from rice bran oil, is used as a substitute for carnauba wax in cosmetics, confectionery, shoe creams and polishing compounds. It is an edible oil which is used in the preparation of vegetable ghee.

Composition[edit]

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 Propreties of Crude & 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 95-100 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[edit]

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.

One litre packing for Rice Bran cooking oil in India

Cholesterol[edit]

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.[4] Results of an animal study[5] 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[edit]

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 after taking a supplement of the purified concentrate for four to six weeks.[6]

Antioxidant stability[edit]

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.[7]

See also[edit]

References[edit]

  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. Retrieved 2012-03-01. 
  2. ^ http://www.riceactive.com/?page_id=203
  3. ^ SEA HandBook-2009,By The Solvent Extractors'Association of India
  4. ^ 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. 
  5. ^ 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.
  6. ^ 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. 
  7. ^ 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". International Journal of Food and Nutritional Sciences 1 (1): 110–117. Retrieved December 2012.