关键词: 紫薯；奶酪；发酵工艺；滴定酸度；膳食纤维

Abstract: Milk and purple sweet potato were used to produce purple potato supplemented cheese and the effect of the fermentation process on the change in dietary fiber content was investigated. Purple sweet potato, fermentation temperature and time were optimized using one-factor-at-a-time method and response surface methodology. The contents of nutrients and dietary fiber in cheese samples were measured by the national standard methods. The results indicated that the optimal process parameters were obtained as follows: 4% purple sweet potato flour, and fermentation at 42 ℃ for 8 h. The cheese prepared using the optimized conditions consisted of 19.79% protein, 15.62% fat and 46.75% moisture and contained 2.97 CFU/g of mold and its titratable acidity 78.03 °T, which met the national standards. In addition, the cheese had a dietary fiber content of 0.106 mg/100 g and its structure and texture was uniform. It was good in appearance with a light purple color and had the characteristic aroma of milk and the unique aroma and flavor of purple sweet potato.

Key words: purple sweet potato; cheese; fermentation process; titratable acidity; dietary fiber