Study on enzymolysis of sweet potato total starch and fermentation yoghurt from sweet potato

To produce sweet potato yoghurt by enzymolysis and fermentation of sweet potato pulp.The sweet potato pulp was hydrolyzed by cellulase andα-amylase to produce the sweet potato pulp.The optimal enzymolysis conditions were determined by single factor and orthogonal experiment.About 42%of juice rate could be obtained at followed conditions:cellulase dosage 0.7%, time 3h, the rate of water and sweet potato pulp 5:1, pH6.5.And then the sweet potato milk was fermented by lactobacillus to produce the sweet potato yoghurt.The optimal fermentation conditions were determined by orthogonal experiment as follows:the proportion of milk powder with sweet potato pulp 5:5, vaccination 5%, fermentation temperature 37℃and the amount of sucrose 4%.The physical, chemical and sensory index of sweet potato yoghurt would be the best at such fermentation process.