喷雾干燥法制备紫薯全粉的研究

Study on Preparation of Whole Purple Sweet Potato Powder by Spray Drying Method

以紫薯为原料,采用喷雾干燥法制备紫薯全粉,研究进风温度、出风温度、进料浓度及喷雾压力对紫薯全粉碘蓝值及基本成分、品质特性的影响。通过正交试验确定喷雾干燥法制备紫薯全粉的最优工艺条件为喷雾压力1.8 kg/cm2、进风温度180℃、进料浓度14 g/100 g、出风温度90℃,此时碘蓝值为27.01。与热风干燥相比,喷雾干燥法制备的紫薯全粉粗蛋白、淀粉、花色苷损失较少。进一步测定紫薯全粉的加工特性,其持水性比持油性好;3%盐溶液、9%糖溶液或pH值3溶液均有助于提高其胶凝特性;添加一定量的食盐可提高其凝胶的冻融稳定性。

The whole powder of purple potato was prepared by spray drying method with purple potato as raw material,and the effect of inlet air temperature,outlet air temperature,feed concentration and spray pressure on iodine blue value,basic composition and quality characteristics of purple potato powder was studied.The optimal spray drying parameters for preparing whole purple sweet potato powder were as followed through orthogonal experiment:Spray pressure 1.8 kg/cm^2,temperatures of inlet wind 180℃,feed concentration 14 g/100 g and out let wind 90℃,with the iodine blue value of PSP granules 27.01.Compared with hot-air drying,the loss of crude protein,starch and anthocyanin in the whole purple potato powder prepared by spray drying method was less.After processing characteristics of PSP powder further determined it showed that the powder was more powerful on water holding capacity than that of on oil holding capacity.The gelatinization capacity of granules was improved under the condition of 3 percent of salt,9 percent of sugar or the solution of pH 3;Adding salt was benefit for increasing freeze-thaw stability of granules.