Rice Bran Oil is a unique vegetable oil produced from the outer brown layer of rice which is removed in the form of rice bran during the polishing process of the rice milling industry. Besides having an ideally balanced fatty acid profile, it is rich in natural anti-oxidants and unique nutraceuticals. A number of scientific studies conducted in India & abroad have well documented the better cholesterol lowering properties of rice bran oil as compared to other conventional vegetable oils. All these studies have attributed these properties of the oil to the presence of unique nutraceuticals in this oil known as Oryzanol & tocotrienols.
Rice Bran Oil is extensively used in Japan, Korea, China, Taiwan and Thailand as premium edible oil. It is the conventional & the most favourite cooking medium of the Japanese and is popularly known as "Heart Oil" in Japan. It has acquired the status of a "Functional Food" or a "Health Food" in Western Countries.
India is the second largest producer of paddy in the world after China contributing about 23% to the total world production of paddy. It has a potential to produce over one million tonne of this nutritious oil. Rice Bran Oil extraction started in India about 40 years back. It was in the middle of 60's that a beginning was made in India for the extraction of oil from rice bran with the help of solvent extraction process wherein food grade hexane is used to extract oil from rice bran. Initially the entire quantities of rice bran oil produced in India were used as raw material for the soaps & detergent industry as the free fatty acid content of the oil was very high.
In the early eighties, the Government of India introduced money credit scheme to encourage the use of rice bran oil as a product mix in vanaspati (hydrogenated fat) wherein substantial rebate from the payment of excise duty on vanaspati was given for use of rice bran oil in the manufacture of vanaspati. This scheme encouraged the production of edible grade rice bran oil containing low levels of free fatty acid ranging between 2 to 5%. Low FFA rice bran oil was extracted from rice bran produced in the rice milling industry engaged in the production of parboiled rice. Due to partial inactivation of enzymes responsible for increase of free fatty acid content in the oil, during the parboiling process, it was possible to produce low FFA oil from rice bran produced by the rice milling industry engaged in the production of parboiled rice. This oil was used by the vanaspati industry after refining through the conventional process of chemical refining wherein alkali was used to remove the free fatty acids.
It was only in the mid of eighties that the Industry in India started gearing up for the production of refined rice bran oil as a direct cooking medium. In 1986, standards for refined rice bran oil were laid down under the Indian food laws and the oil was permitted to be sold as a direct cooking medium. The only technology available at that time was the chemical refining process which was used to refine all kinds of vegetable oils. The same process was used for refining of rice bran oil. This process was used only for refining of low FFA rice bran oil which was produced using rice bran produced in the parboiled rice milling industry. It was not possible to use this process for refining of crude rice bran oil produced from the raw rice bran due to higher refining losses which were 2.5 to 3 times of the free fatty acids present in the oil.
In the mean time, efforts were made to develop technologies for stabilizing the raw rice bran so as to extract low FFA crude rice bran oil from the stabilized rice bran which could be further refined for human consumption. Various technologies of stablization such as steam stablization, chemical stablization & extrusion technology were tried for this purpose. But none of the technologies became popular because of various techno-commercial reasons. Ultimately the search started for some alternative refining technologies which could economically refine crude rice bran oil with higher levels of free fatty acids.
In the late eighties, Miscella refining was tried to refine rice bran oil but it could not become popular because of commercial reasons. In the middle of nineties, the industry started trying physical refining technology for refining rice bran oil which was mainly used for refining palm oil. Initially the industry could not get much success in refining rice bran oil through this technology because of lack of appropriate pre-treatment technologies which could bring down the phosphorus content after pre-treatment below 5 P.P.M. which is a pre-requisite for physical refining. It was not possible to bring down the 'P' content in rice bran oil through the conventional phosphoric acid degumming process. So the need was felt for developing appropriate pre-treatment technologies so that the industry could make the best use of the physical refining technology for refining of rice bran oil.
Since 1998, The Solvent Extractors' Association of India, started holding National level seminars to encourage the production and use of rice bran oil as a healthy cooking oil. These seminars created awareness among consumers, technocrats, researchers, medical professionals and also among the government circles. TMOP&M under the Union Ministry of Agriculture sponsored research projects for developing cost-effective technologies for physical refining of the Rice Bran Oil. I.I.C.T., Hyderabad & R.R.L., Trivandrum came out with excellent process technologies of pretreatment of rice bran oil for physical refining. R.R.L. developed a pre-treatment technology known as "simultaneous degumming & dewaxing process" wherein calcium cloride is used to bring down the 'P' content below the desired levels. Similarly I.I.C.T., Hyderabad developed an "enzymatic degumming process" in which enzyme is used to remove the phosphorus content below the desired levels.
Development of these pre-treatment technologies have really revolutionalised the rice bran oil processing in India. A number of new rice bran oil refining plants have been set up incorporating these new technologies with grant-in-aid assistance from the TMOP&M. Majority of these units are based upon IICT technology. The oil produced by these units is good in colour and rich in nutrients particularly the Oryzanol. These technological developments have boosted the production of refined rice bran oil in the country. Indian markets are now witnessing many brands of refined rice bran oil. Even the leading brand players in India have launched new brand variants using 70 to 80% refined rice bran oil. Now the consumers in India can enjoy the benefits of this unique gift from the mother nature.
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At 60th Annual Convention of OTAI, Hyderabad on 2-3rd dec. 2005
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