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.

The physicochemical characteristics and minor component contents of blended oils packed in pouches in relation to starting oils used for blending were studied over a period of 6 mon at two storage temperatures and humidity conditions: 27°C/65% RH and 40°C/30-40% RH. Color, PV, FFA value, β-carotene content, tocopherol content, and oryzanol content of the oils were monitored at regular intervals. The color, PV (0.6-20.7 meq O 2 /kg , FFA value (0.08-2.1%), tocopherol content (360-1700 ppm%), oryzanol content (460-2,000 mg%), and sesame oil antioxidants (400-2,000 mg%) were not changed in either the starting oils or their blends. Oils and oil blends containing a higher initial PV (18.9-20.7 meq O 2 /kg) showed a slight reduction in value at 40°C, whereas oils having lesser PV of 5-10 showed a slight increase during the storage period. Among the minor components studied, only β-carotene showed a reduction, 8.9-60.2% at 27°C and 48-71% at 40°C, for the different oil blends studied. The observed results indicated that the packed oil blends studied were stable under the conditions of the study, and the minor components, other than β-carotene, remained unaltered in the package even at the end of 6 mon of storage.