The Preparation Of Functional Rice Bran Oil And Its Effect On Blood Lipids Regulation

Rice bran oil is a high nutritional value oil，it has a more reasonable proportionof the fatty acid composition，there is only20%saturated fatty acid but80%unsaturated fatty acid，of which42%oleic acid and38%linoleic acid. It isbasically accord with the optimum ratio1:1of oleic acid and linoleic acid whichrecommended by International health organization.What’s more, rice bran oilcontains a variety of biological activity factors (such as oryzanol、vitamin E、steroletc)，and the total content in rice bran oil reached4.2%. At the same time，there aresome problems in the development and utilization of rice bran oil. High acid valueof rice bran oil caused it is more difficult to deacidification than general grease，andin the traditional process of alkali refining，some active substances such as oryzanolhave a huge loss. Therefore，it is not only the difficulty but also the research hotspot to find a superior refining technology which can reduce the acid value of ricebran oil as well as reduce the loss of functional factors such as oryzanol, vitamin Eand sterol.The main research of this paper are the preparation of the functional rice branoil and its effect on blood lipids regulation，the conclusion obtained as following:（1）Study the process of solvent extraction to deacidificate，and throughcomparing，selected the methanol as the best extraction solvent，and orthogonaldesign was used for combination with single factor. Then，the optimum conditionswere：the temperature is30℃，the solvent dosage is2.4(V/W)，the time is30minand extract five times；Finally the acid value of the oil drop to2.81，and the contentof oryzanol maintained1.35%.（2）Using the rice bran oil as the raw materials，which deacidificated threetimes by solvent extraction，studied the process of adsorbent to deacidification，andthrough comparing，selected the DA5as the best adsorbent，and orthogonal designwas used for combination with single factor. Then，the optimum conditions were： the temperature is75℃、the amount of adsorbent is1.8%and the time is35min；Finally the acid value of the oil drop to2.75， and the content of oryzanolmaintained1.35%.（3）Comparing the deacidification method of solvent extraction three timescombinated with adsorbent， solvent extraction five times， alkali refining andphysical refining，it proved that the method of solvent extraction three timescombinated with adsorbent get the best effect， condiderating the effect ofdeacidification and reduce the loss of functional factor such as oryzanol, vitamin Eand sterol.（4）Contrasting the lipid regulating efficacy of functional rice bran oil withgeneral rice bran oil，study found，functional rice bran oil can effectively reduce thecontent of total triglycerides(TG)，low density lipoprotein cholesterol(LDLC)，and improve the content of high density lipoprotein cholesterol(HDLC)，but theeffect for total cholesterol content is not obviously； And have a doseeffectrelationship for the higher dose of rice bran oil， the more effective of lipidreduction. While the general rice bran oil has the lipid regulating efficacy either,but not that significant.