Process Optimization for the Development of a Fermented Milk Beverage of Purple Sweet Potato Hydrolysate

Purple sweet potato hydrolysate and fresh bovine milk were mainly used as raw materials to develop a fermented milk beverage with low viscosity,relatively stable emulsion system and palatable taste.Using one-factor-at-a-time coupled with orthogonal array design method,the optimal fermentation substrate composition was determined to be comprised of 60% milk,30% purple sweet potato hydrolysate and 8% sucrose and that fermentation parameters were optimized as follows: inoculum size 3%,fermentation temperature 41 ℃ and fermentation time 3 h.