Study On Enzymatic Hydrolysis For Production Of Purple Sweet Potato Beverage

This paper studied on the process conditions of preparation purple sweet potato beverage for enzyme method taking the purple sweet potato(Solanum tuberdsm)as main raw material.The beverage was made from purple sweet potato that had been treated by enzymolysis,clarifying,filtration,deployment,sterilization.The main results obtained were as follows:Nutrient content determined for purple sweet potato included water 72.46g/100 g,ash 0.58g/100 g,carbohydrate 22.36g/100 g,protein 1.12g/100 g,crudefat 0.18g/100 g,dietary fiber1.67g/100 g,anthocyanins 46.58mg/100 g.On the basis of single factor optimizing test and orthogonal test,the optimum technological parameters of enzymolysis for purple sweet potato pulp were determined.They included 1:3 of the solid-to-liquid ratio,0.1% thermostable ?-amylase,liquefaction time for 25 min,liquefaction temperature at 90?,pH 5.5.Saccharify phase conditions were at 60? for 150 min,pH 4.0,0.15% saccharifying enzyme.Study on processing technology of purple sweet potato beverage.The optimum conditions for the clarification process included 0.15% pectinase,0.1% cellulase,pH 4.5,time of clarify for150 min.The best formula of purple sweet potato beverage was 7% sugar,20% purple sweet potato juice,0.15% citric acid.The best sterilization parameter of beverage was at 100? for15 min.The stability of purple sweet potato beverage was good in the former 120 days.The beverage began to appear trace particles after 135 days and a small amount of precipitation after180 days.