枸杞山药凝固型酸乳的发酵工艺研究

以牛奶为原料,枸杞山药为主要辅料,利用保加利亚乳杆菌,嗜热链球菌和植物乳杆菌按照体积比1∶1∶1进行发酵,采用单因素和Box-Behnken试验设计,结合主成分分析优化枸杞山药凝固型酸乳的生产工艺进行研究,并对酸乳中的pH值、可溶性固形物、乳酸、蛋白质、总黄酮与活菌数及感官评分进行测定分析。结果表明,枸杞山药凝固型酸乳的最佳发酵条件为在鲜牛乳中,枸杞汁添加量为12%、山药汁添加量为10%、接种量为5%。在此发酵条件下得到枸杞山药凝固型酸乳的综合得分值为0.9932,与理论综合评分值0.9934接近,说明响应面结合主成分分析法优化对枸杞山药凝固型酸乳的品质的综合优化具有较好的效果,为其他食品的多参数品质分析提供一定的理论依据。

Study on Fermentation Technological Conditions of the Solidifying Yoghurt with Lycium barbarum and Chinese yam

In this study,Lycium barbarum and Chinese yam as the main adjuvant,Lactobacillus bulgaricus,Streptococcus thermophilus and Lactobacillus plantarum were used to ferment according to the volume ratio of 1∶1∶1.Single factor and Box-Behnken design were used to optimize the production process of Lycium barbarum and Chinese yam coagulated yoghurt.The pH value,soluble solids,lactic acid,protein,total flavonoids,viable bacteria and sensory score of yoghurt were determined and analyzed.The results showed that the optimum fermentation conditions of the solidifying yoghurt with Lycium barbarum and Chinese yam were as follows:12%Lycium barbarum juice,10%Chinese yam juice and 5%inoculation.Under this fermentation condition,the comprehensive score of yoghurt was 0.9932,which was close to the theoretical comprehensive score of 0.9934.It was concluded that response surface methodology combined with principal component analysis had a good effect on the comprehensive optimization of the quality of the solidifying yoghurt with Lycium barbarum and Chinese yam barbarum,and provided a theoretical basis for the quality analysis of many other food parameters.