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With the development of the social economy, people are increasingly concerned about the health problems. In recent years, people from the consumption of high-fat animal fats gradually transition to vegetable fats and oils food nutrition and health. Millet fine bran is processed into a fine millet Millet shelling byproduct, rich in nutrients, its prepared bran oil is a healthy oil fatty acid content ratio is more consistent than the common edible oil nutrition requirements, in addition to food, but also widely used in medicine, health care products, cosmetics and other industries. Bran oil extraction rate of the indexes, the study of supercritical carbon dioxide extraction conditions of bran oil. By supercritical carbon dioxide fluid extraction - distillation study summarizes the extraction pressure, extraction temperature, extraction time, the impact of the carbon dioxide flow of oil yield, as well as distillation pressure distillation temperature of distillation. The results showed that the optimum extraction conditions for the extraction pressure 30MPa, extraction temperature 45 ℃, extraction time 2h, carbon dioxide flow 50kg / h, bran particle size of 40 mesh, moisture content of 7%. Under the conditions of the oil was 19.69%. The most suitable conditions for supercritical carbon dioxide distillation bran oil extraction pressure 30MPa, extraction temperature 45 ° C, extraction time 2h, carbon dioxide flows 50kg / h, the distillation column pressure 10MPa, the distillation temperature distillation Ⅰ: 40 ° C, fine distillate Ⅱ: 45 ° C, Distillation III: 50 ° C, distillation Ⅳ: 55 ° C. By measuring, supercritical extraction method to extract the bran oil containing higher unsaturated fatty acids, especially those containing up to 67.8% of linoleic acid. Bran oil extracted by comparing supercritical extraction of the physical and chemical indicators are better than the commercially available bran oil. Therefore, is a good method for extracting bran oil by supercritical carbon dioxide fluid extraction - distillation. China has rich bran resources, an annual output of about 200 million tons of millet bran production of more than one hundred thousand tons, its development is not only effective use of agricultural waste resources, reduce waste, but also led farmers to get rich, to improve the standard of living of the people significance. Bran oil's price is about 10-60 yuan / ton. China to vigorously develop bran oil industry prospects. From chaff, bran oil is extracted with supercritical carbon dioxide fluid, has many advantages, such as in the extraction has a high ability to dissolve the faster the mass transfer rate, good flow properties and balance, have good tunability and easy to control, and to maintain the biological activity of the nutrients bran oil. And to avoid environmental pollution, the process is non-toxic and non-polluting, clean production.
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