Isolation of oligosaccharides from soybean molasses by alcohol precipitation

The crude soybean oligosaccharides were extracted with ethanol from soybean molasses,and then the soybean oligosaccharides were purified by saturated lime water.The extraction conditions were optimized through single factor and orthogonal experiments as follows:volume fraction of ethanol 95%,ratio of solvent to raw material 25∶1,extraction temperature 50℃,extraction time 2 hours.Under the optimal conditions,the yield and purity of crude soybean oligosaccharides were 55.0% and 66.3%,respectively.The finished product with the content of 84% soybean oligosaccharides was obtained by purifying the crude soybean oligosaccharides with saturated lime water at room temperature.