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Bran during storage prone to rancidity and other deterioration caused by the decline in quality, need to be stabilized to improve the storage quality of the rice bran, the industrial application of the method is the use of the extrusion process, but the higher investment cost of the extrusion method, the processing flexibility is small , impact on the nutritional and functional properties of rice bran components. The microwave fast and efficient inhibition of rice bran lipase and microwave stabilization is a more promising new technology, the subject of rice bran as raw material, research the effect of microwave conditions stabilized rice bran, to determine the appropriate microwave conditions, comparing microwave stabilized rice bran, rice bran oil solvent extraction and enzymatic extraction of rice bran oil and rice bran protein. Main results are as follows: 1. The bran microwave stabilized conditions: Suitable microwave stabilized condition, and rice bran processing 2.5min in a microwave dose of 4.5 Kw / Kg. Microwave stabilized rice bran under (25 ° C, 37 ° C) at room temperature for 90 days of storage, the fatty acid value of not more than 15mgKOH / g. Microwave stabilized rice bran protein solubility, emulsification increased, and water holding ability. Compared with other heat treatment, the lowest microwave treatment of rice bran oil acid value, peroxide value highest. After storage, the acid value of the microwave treatment of rice bran oil, the smallest change in lightness, the peroxide value decreases up after microwave treatment of rice bran oil, rice bran best quality. 2 Solvent Extraction rice bran: best microwave method for stabilizing treatment bran and rice bran oil suitable conditions and extracted with n-hexane, 1:5 (rice bran: solvent, w / v) stock solution than at 50 ° C. extracted under 20min, rice bran oil extraction rate of 94%. Spherical model of rice bran oil extraction exponential kinetic equation, with high fitting accuracy and the grease the diffusion coefficient in the extraction process 0.0038mm2/min, diffusion can 1109J/mol. The microwave treatment is beneficial for rice bran oil and protein extraction. Isopropanol as a solvent, the rice bran oil extraction rate of n-hexane and acetone. Enzymatic extraction of rice bran oil and protein: protease enzyme dosage, reaction temperature and time have a significant impact on the rice bran oil and protein extraction rate, the suitable rice bran oil and protein extraction conditions the protease add 1.0% at 55 ℃ The following extract 5h. Under this condition, the extraction rate of the rice bran oil and protein, respectively, 72.85% and 83.62%, than solvent extraction is low. 4 The quality characteristics of the rice bran: rice bran oil, unsaturated fatty acid content is higher, the microwave stabilized rice bran oil, oleic acid, linoleic acid content decreased. Enzymatic extraction of rice bran oil peroxide value slightly higher than the solvent method, but lighter in color, in addition to the Koh slightly higher enzymatic extraction of rice bran oil can reach three bran oil GB19112-2003 standards.
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