Study On Preparation Technology Of All The Nutrition Sweet Potato Granular

Sweet potato granular is a sweet potato dehydration products, which includes all the drymaterials except those in the potato skin. When it is rehydrated, the sweet potato granularlooked like mashed potato stays the same in nutrition, flavor and taste as fresh sweet potato.Sweet potato granular is easy to store and transport compared to sweet potato. The maindrying methods of drying sweet potato are blast drying and drum drying in the presentproduction, while the nutrition loss of the the production is large and the rehydration is poor.The research mainly use vacuum drying and spray drying for sweet potato granularpreparation to get sweet potato granular with smaller loss of nutrients and good rehydration.And its applicable properties was also studied on.The main research contents and results are as follows:1. Vacuum drying method was chosen to preparing sweet potato cooked granules. Theeffects of vacuum drying temperature, concentration of calcium, cooking time andconcentration of the added emulsifier on the free starch content of sweet potato cookedgranules was discussed. The optimal conditions were as followed through orthogonalexperiment: the vacuum drying temperature40℃，concentration of calcium25ppm,concentration of added emulsifier0.2%, cooking time12min(the quality of sweet potatogranules are best), and the free starch content of sweet potato cooked granules is21.89%.2. Vacuum drying method was chosen to preparing sweet potato uncooked granules. Theeffects of vacuum drying temperature, concentration of calcium and concentration of theadded emulsifier on the free starch content of sweet potato uncooked granules wasdiscussed. The optimal conditions were as followed through orthogonal experiment: thevacuum drying temperature40℃，concentration of calcium75ppm, concentration ofadded emulsifier0.3%(the quality of sweet potato granules are best), and the free starchcontent of sweet potato uncooked granules is26.84%.3. Vacuum drying method was chosen to preparing sweet potato baked granules. The effectsof baking temperature,vacuum drying temperature,and concentration of the addedemulsifier on the free starch content of sweet potato baked granules was discussed. Theoptimal conditions were as followed through orthogonal experiment: the bakingtemperature190℃,the vacuum drying temperature40℃， concentration of addedemulsifier0.1%(the quality of sweet potato granules are best), and the free starch contentof sweet potato baked granules is17.26%.4. Spray drying method was chosen to preparing sweet potato cooked granules. The effects of inlet air temperature, cooking time, liquid ratio on the free starch content of sweetpotato cooked granules was discussed. The optimal conditions were as followed throughorthogonal experiment: the inlet air temperature190℃，cooking time9min, liquid ratio1:4(the quality of sweet potato granules are best), and the free starch content of sweetpotato granules is33.28%.5. Study the effects of four processing technology on sensory properties,physicochemicalindex and application quality of sweet potato granular. There is no obvious differences inphysicochemical index.But there are obvious differences in the free strach content,waterholding capacity,oil holding capacity, transparence and cementing.