响应面法优化胡萝卜-发酵蓝莓奶片的工艺研究

以脱脂奶粉、胡萝卜粉、发酵蓝莓冻干粉为原料制备胡萝卜-发酵蓝莓奶片,并进行相关工艺优化。通过正交试验确定发酵蓝莓的最佳条件,用总抗氧化能力进行鉴定,采取真空冷冻干燥的方法将蓝莓发酵液制成冻干粉。以奶片感官评分为响应值,通过单因素实验和响应面法优化奶片工艺。结果表明,发酵蓝莓的最佳条件为发酵温度35 ℃、菌种添加量5%、发酵时间25 h,此条件下蓝莓发酵液的总抗氧化能力为230.158 U/mL,较蓝莓汁发酵前提高了33.18%。奶片的最佳制备工艺配方为奶粉:果蔬粉=2:1、麦芽糖醇添加量7.5%、柠檬酸添加量0.3%、硬脂酸镁添加量0.5%,此条件下的感官评分为95分。本产品保有蓝莓的营养价值,具有较好的市场应用前景。

Optimization of Carrot-fermented Blueberry Milk Tablet by Response Surface Methodology

The carrot-fermented blueberry milk tablets were prepared from skim milk powder,carrot powder and fermented blueberry lyophilized powder,and the related process was optimized. The optimal conditions for fermenting blueberries were determined by orthogonal test with the total antioxidant capacity for identification. The blueberry fermentation broth was made into lyophilized powder by vacuum freeze-drying method. The milk tablets process was optimized by single factor experiment and response surface method with the sensory score of milk tablets as the response value. The results showed that the optimal conditions for fermenting blueberries were fermentation temperature 35 ℃,5% strain addition,fermentation time 25 h. Under this condition,the total antioxidant capacity of blueberry fermentation broth was 230.158 U/mL,which was 33.18% higher than that before blueberry juice fermentation. The best preparation formula for milk tablets was milk powder∶Fruit and vegetable powder=2∶1,7.5% maltitol,0.3% citric acid,0.5% magnesium stearate,the sensory score under this condition was 95 points. This product retains the nutritional value of blueberries and has a good market application prospect.