The effect of different processing steps of refining on retention or the availability of oryzanol in refined oil and the oryzanol composition of Indian paddy cultivars and commercial products of the rice bran oil (RBO) industry were investigated. Degumming and dewaxing of crude RBO removed only 1.1 and 5.9% of oryzanol while the alkali treatment removed 93.0 to 94.6% of oryzanol from the original crude oil. Irrespective of the strength of alkali (12 to 20° Be studied), retention of oryzanol in the refined RBO was only 5.4-17.2% for crude oil, 5.9-15.0% for degummed oil, and 7.0 to 9.7% for degummed and dewaxed oil. The oryzanol content of oil extracted from the bran of 18 Indian paddy cultivars ranged from 1.63 to 2.72%, which is the first report of its kind in the literature on oryzanol content. The oryzanol content ranged from 1.1 to 1.74% for physically refined RBO while for alkali-refined oil it was 0.19-0.20%. The oil subjected to physical refining (commercial sample) retained the original amount of oryzanol after refining (1.60 and 1.74%), whereas the chemically refined oil showed a considerably lower amount (0.19%). Thus, the oryzanol, which is lost during the chemical refining process, has been carried into the soapstock. The content of oryzanol of the commercial RBO, soapstock, acid oil, and deodorizer distillate were in the range: 1.7-2.1, 6.3-6.9, 3.3-7.4, and 0.79%, respectively. These results showed that the processing steps-viz., degumming (1.1%), dewaxing (5.9%), physical refining (0%), bleaching and deodorization of the oil-did not affect the content of oryzanol appreciably, while 83-95% of it was lost during alkali refining. The oryzanol composition of crude oil and soapstock as determined by high-performance liquid chromatography indicated 24-methylene cycloartanyl ferulate (30-38%) and campesteryl ferulate (24.4-26.9%) as the major ferulates. The results presented here are probably the first systematic report on oryzanol availability in differently processed RBO, soapstocks, acid oils, and for oils of Indian paddy cultivars.

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The fat-soluble nutraceuticals-oryzanol, tocopherols, and tocotrienols-and FA composition of three varieties of rice-Basmati, Jaya, and parboiled (brown rice is defined as dehulled rice, and brown rice after polishing is known as milled rice)-were investigated. Lipid content ranges were 2.75-4.49% for brown rice and 0.7-1.2% for milled rice. The range in oryzanol content was 500-720 ppm for brown rice, 10,700-14,300 to ppm for brown rice lipids, 70-120 ppm for milled rice, and 4500-6300 ppm for milled rice lipids. Tocopherol content ranged from 22 to 31 ppm for brown rice and 79 to 951 ppm for brown rice lipids while the tocotrienol content ranged from 0 to 26 ppm for brown rice and 0 to 792 ppm for brown rice lipids. Parboiling of paddy rice affected the tocopherol and tocotrienol content adversely, but the oryzanol content remained unchanged. Basmati variety brown rice had the highest tocopherol and tocotrienol contents, although the oryzanol content was lower than that of the Jaya variety brown rice. The FA composition of brown rice differed from that of milled rice for each variety; higher amounts of saturated FA were extracted from the oil of milled rice than from brown rice for all three varieties studied. Brown rice varieties in this study contained all of the fat-soluble nutraceuticals, compared with milled rice.Paper no. J10795 in JAOCS 81, 939-943 (October 2004).

Plastic fats with zero trans fatty acids by interesterification of mango, mahua and palm oilsSpeciality plastic fats with no trans fatty acids suitable for use in bakery and as vanaspati are prepared by interesterification of blends of palm hard fraction (PSt) with mahua and mango fats at various proportions. It was found that the interesterified samples did not show significant differences in solid fat content (SFC) after 0.5 or 1 h reaction time. The blends containing PSt/mahua (1:1) showed three distinct endotherms, indicating a heterogeneity of triacylglycerols (TG), the proportions of which altered after interesterification. The SFC also showed improved plasticity after interesterification. Similar results were observed with other blends of PSt/mahua (1:2). These changes in melting behavior are due to alterations in TG composition, as the trisaturated-type TG were reduced and the low-melting TG increased after interesterification. The blends containing PSt/mango (1:1) showed improvement in plasticity after interesterification, whereas those containing PSt/mango (2:1) were hard and showed high solid contents at higher temperature and hence may not be suitable for bakery or as vanaspati. The blends with palm and mahua oils were softer and may be suitable for margarine-type products. The results showed that the blends of PSt/ mahua (1:1, 1:2) and PSt/mango (1:1) after interesterification for 1 h at 80 7C showed an SFC similar to those of commercial hydrogenated bakery shortenings and vanaspati. Hence, they could be used in these applications in place of hydrogenated fats as they are free from trans acids, which are reported to be risk factors involved in coronary heart disease. For softer consistency like margarine applications, the blends containing palm oil and mahua oil are suitable.