Fermented Product Of Rice Bran And Its Function Evaluation

The rice bran is the surface which attached to the brown rice after hulling rice,and it is the main by-products of rice processing. In our country, resources of rice bran are abundant, but it is mainly used as feed for livestock, its nutrients has not been extracted and used efficiently.With the development of technology of rice bran extrusion processing, rice bran is more easier to conduct the follow-up processing after extrusion processing, and it is the base of comprehensive utilization of rice bran.In this study,Bacillus natto and lactobacillus were used to ferment the rice bran, the optimum strains and conditions of rice bran fermentation were determined, the changes of the main nutrients in the rice bran after the fermentation was analyzed,and ingredients substance in the rice bran befor and after the fermentation were determined and analyzed, the sanitarian functions of fermented rice bran were evaluated through the animal experiment.This is the base of making a new functional food which have variety of probiotics in rice bran.The process of fermented rice bran is as follows:beandregs is 5%,fermentation temperature is 34℃and moisture cintent is 40%.1. Bacillus natto and Lactobacillus(Lactobacillus brevis,Lactobacillus elveticus,Lactobacillus plantarum,Streptococcus thermophilus and Lactobacillus bulgaricus) were used to solid state fermentation of rice bran by single bacteria and mixed bacterias,then it was detemined that the optimum strains are Bacillus natto and Lactobacillus brevis;optimum inoculum propotion is 1:1, optimum inoculum volume is 10%,inoculum mode is incoculate Bacillus natto,3 days later.incoculate Lactobacillus brevis. The process of fermenting rice bran was determined first, then on the basis of one-factor, double-factor interaction tests and the Box-Behnken center-united experimental design principle, the method of response surface analysis with 3 factors,3 levels and the optimum conditions of fermenting. The optimum conditions are as folloes.After fermentation, the circle diameter of nattokinase dissolved reached 12.25mm in fermented rice bran,and the quantity of living of Bacillus natto is 6.8×109cfu/g,the live count of Lactobacillus brevis is 4.5×109cfu/g in it.2.the changes of the main nutrients in the rice bran after the fermentation was analyzed,from this,the opimum period is 5d,the protease activity in the fermented rice bran were 2374.85u/g for 2d and the circle diameter of nattokinase dissolved reached 12.35mm for 5d.The crude protein,fatty acid and amino acid were determined.The results are as follows.The crude protein increased 4.32%; the linokeic acid and linolenic acid increased 0.82% and 0.57% respectively in the fatty acid; there are 13 kinds of amino acids had increased in the 17 kinds of amino acids in fermented rice bran.3.The glutelin in rice bran,un-fermented rice bran and fermented rice bran was comparative analyzed by SDS-PAGE.It was found that there were some electrophoretic bands disappeared about the glutelin in fermented rice bran in the range of their relative molecular weight,it explains that these proteins had been degraded and used in the processing of rice bran fermentation.4. The effects of fermented rice bran on reducing serum lipid in the experimental rats was found by the research.The results that there are a obvious effect to reduce TC of experimental hyperlipidemia rats by fermented rice bran,and it is better than stable rice bran;In high doses,fermented rice bran can reduse TG and raise the level of HDL-C on experimental hyperlipidemia rats.In this experiment, no case was natural death,sothe fermented rice bran is safe.