Extraction of sweet potato polysaccharides by slowly freezing cooperative with the micro wave and hot water immersion process
With the fresh sweet potato for material,through comparing with the heat water immersion extraction,the micro wave hot water immersion extraction,the slowly freezing immersion extraction,the slowly freezing and heat water immersion extraction,the slowly freezing cooperative with the micro wave water immersion extraction,to determin the last method is the best one.Separately investigated the factors,which are the time of slow frozen,the material-liquid ratio,the time of extraction,the temperature of extraction,the power of microwave,the time of microwave,they all effect on the extraction rate of polysaccharide for sweet potato,and through orthogonal experiment L9(34) pairs the process parameters of extraction in optimization.The results show that its best conditions are that:the time of slow frozen is 20 h,the temperature of extraction is 80 ℃,the time of extraction is 2 h,the time of microwave is 4 min,the material-liquid ratio is 1:15,the power of microwave is 400 W,the rate of extraction is 26.6%.