桑黄风味酸奶发酵工艺优化

该试验以桑黄发酵液、脱脂奶粉为主要原料，将保加利亚乳杆菌、嗜热链球菌、乳双歧杆菌1∶1∶1混合作为发酵菌剂，生产桑黄酸奶。通过单因素试验和正交试验分别考察桑黄发酵液添加量、奶粉添加量、白砂糖添加量、发酵菌剂接种量、发酵时间和发酵温度对桑黄风味酸奶品质的影响。结果表明，桑黄风味酸奶的最佳发酵工艺条件为桑黄发酵液添加量15 mL/100 mL、奶粉添加量17 g/100 mL、白砂糖添加量7 g/100 mL、发酵菌剂（8.4×108 CFU/mL）接种量5 mL/100 mL、发酵时间5 h、发酵温度42 ℃。在此优化条件下，制备的桑黄风味酸奶感官评分为92.2分，蛋白质和脂肪含量分别为1.86 g/100 g、0.6 g/100 g、1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除率为46%。

Optimization of fermentation technology of Phellinus igniarius flavor yoghurt

Using Phellinus igniarius fermentation broth and defatted milk powder as main raw materials, and the 1∶1∶1 mixture of Lactobacillus bulgaricus, Streptococcus thermophilus and Bifidobacterium lactis as fermentation agent, P. igniarius yoghurt was produced. The effects of P. igniarius fermentation broth addition, milk powder addition, sugar addition, fermentation agent inoculum, fermentation time and temperature on quality of P. igniarius flavor yoghurt were investigated. The results showed that the optimal fermentation technology conditions of P. igniarius flavor yoghurt were as follows: P. igniarius fermentation broth addition 15 ml/100 ml, milk powder addition 17 g/100 ml, sugar addition 7 g/100 ml, fermentation agent (8.4×108 CFU/ml) inoculum 5 ml/100 ml, fermentation time 5 h and temperature 42 ℃. Under the optimal conditions, the sensory score of the prepared P. igniarius flavor yogurt was 92.2. The contents of protein and fat were 1.86 g/100 g and 0.6 g/100 g, respectively, and the 1,1-diphenyl-2-picrylhydrazyl radical scavenging rate was 46%.