The Research On The Reduction On The Levels Of Oligosaccharide In Soybean And Its Mathematical Model

Soybean is an excellent source of plant protein, but the presence of flatulence factor-oligosaccharide has limited the development of soybean protein, so the effective reduction ofoligosaccharide is practically important for providing excellent and inexpensive soybean protein andimproving the bioavailability of soybean.By employing the physical treatment, enzymatic hydrolysis and microbiological fermentation,the optimal technological parameters had determined and the oligosaccharide levels in soybean waseffectively reduced. Additionally, the mechanical model for oligosaccharide levels fluctuation duringthe soaking and boiling processes was also defined and its change trend was dynamically predicted.Details are following:①For the physical treatment, considering the loss of water-solvable substance during the boilingperiod, the optimal boiling time was defined as 90min at 100℃and the concentrations of sucrose,raffinose and stachyose was reduced by 62.0％,72.4％and 54.6％.When the boiling temperature roseup to 121℃, the optimal boiling time was defined as 45min and the concentration of sucrose,raffinose and stachyose was reduced by 79.％, 84.7％and 77.6％.②By employing the diffusion mathematical model, the oligosaccharide change mechanismduring the soaking and boiling periods. For soaking process, the beginning part of soaking period canbe eexpalined by diffusion mechanism. But the latter part can not be explained by diffusionmechanism only fot the presence of respiration phenomenon with the soaking time prolonged. But forthe boiling period, the experimental data and predicated data were inosculated fairly well and theoligosaccharide concentrations in the soaking water and boiling water basically conform with the ruleof mass conservation. All these means during the boiling period, the diffusion mechanism only canexplain the oligosaccharide change mechanism.③The effects of soaking time,soaking temperature,boiling time,boiling temperature andsoybean dimension factors etc on the diffusion velocity of oligosaccharide were analyzed: And theeffects of soaking time on the diffusion velocity during the boiling period was also examined.④The oligosaccharide concentration during the germinating period was also examined and ansignificant reduction was found for raffinose and stachyose concentrations. They respectively reduced to the levels of 0.091％and 0.37％.⑤The effects of crudeα-galactosidase enzyme extracted from germinating soybean on thesoybean powder and original ground soybean were analyzed. After a probation of 6h at 40℃, theconcentrations of sucrose, raffinose and stachyose was reduced by 69.5％,79.0％,80.3％respectively,while the sucrose concentration in the soybean powder was reduced by 87.9％and the concentrationsof raffinose and stachyose was not detected.⑥Oligosaccharide concentrations during the fermentation by Rhizopus oligosporusandNeurospora sitophila were examined and They were reduced to the non-detection levels when thefermentation time reached 36h and 32h respectively.100...