Research On Preparation Of Germinated Brown Rice Flour(Porridge)

In this paper, germinated brown rice which riched in γ-aminobutyric acid (GABA) wasmade of brown rice, using xylanase and cellulase treat with germinated brown rice, in order tolooser it’s cortex structure. In this condition, produced germinated brown rice flour throughrollers drying method, germinated brown rice porridge was prepared just around80℃. Wefocus on maintain the cortex structure of germinated brown rice and the process conditions ofproduct preparation, at the same time, the different of structure and properties of germinatedbrown rice which disposed by enzyme and the eating quality of brown rice porridge whichproduced by different treatments were also studied.The germinant conditions of brown rice which riched in GABA were optimized by singlefactor, orthogonal design and response surface analysis (RSA).The optimal parameters wereas follows: soaking temperature34℃, soaking time14h, germination temperature30℃,germination time19.8h, and the concentration of calcium chloride was0.84%. Aftergerminating on this condition, the content of GABA of geminated brown rice reached131.91mg/100g, which was about3times more than that of the ungerminated brown rice. Thedisintegrating conditions were studied by single-factor tests. To ensure the structure of cortex,the parameters were as follows: in pH5.0, both of the concentration of xylanase and cellulasewere0.1%, enzymatic treatment time5h, enzymatic treatment temperature45℃. Theconcentration of glucose was8.39mg/ml after the cortex was treated on this conditions.Observed the cortex microscopic structure of brown rice, germinated brown rice andenzymatic treatment germinated brown rice by scanning electron microscope (SEM), thecortex structure of enzymatic treatment germinated brown rice was looser than brown rice andgerminated brown rice. It explains that the endogenous enzymes and exogenous enzymes canbe applied to the brown rice cortex. The cortical fiber structure of germinated brown ricechanged significantly after enzymatic hydrolysis. The Brabender viscosity curve shows thebrown rice has good hot paste stability and not easily aging, the setback is157BU and thebreakdown is87BU, which is lower than brown rice and germinated brown rice.The product conditions of germinated brown rice flour (porridge) were optimized bysingle factor and orthogonal design. The optimal parameters were as follows: serifluxconcentration45%, boil down time15min, boil down temperature65℃, steamy pressure0.65MPa. After demonstration test of the condition, rehydration rate of geminated brown rice flour is5.5, sensory evaluation score is56, total points are86。Through comparison of the properties of brown rice flour, germinated brown rice flourand enzyme treatment germinated brown rice flour found that the germinated brown ricepowder which after the enzyme treatment have better transparence and anti-sedimentation. Itshows that the endogenous enzymes and exogenous enzymes changed the structure as well asimproved its transparency and sedimentation. After enzyme treatment of germinated brownrice, the content of GABA of geminated brown rice powder reached87mg/100g, which wasabout2times more than that of the brown rice without any treatment. It shows that thecontent of GABA of powder is decreased after roller drying. However, the whole trend isincreased. The product is able to reach peak viscosity (748BU), after rehydration with waterof80.8℃by the test of BrabenderViscograph. The peak viscosity is higher than the threekinds of unprocessed brown rice flour (428BU,289BU,177BU), it shows that this processingmethod can improve the product’s peak viscosity. This experiment produced germinatedbrown rice flour (porridge) has good shape, fast rehydration and eating quality has beengreatly improved.