Process Application of Lactic Acid Bacteria in Traditional Yak Yoghurt in Qinghai Pastoral Areas

Research to investigate the effect of improving the quality of yak yogurt, composite fermentation was prepared with lactic acid bacteria strains isolated from traditional yak yoghurt in Qinghai pasture area, and the response surface methodology was used to optimize the process parameters of yak yoghurt fermentation in combination with Plackett-Burman and steepest climb tests. The results showed that the optimal process parameters of yak yoghurt with the addition of composite bacteria Y2-10 and N5-9 fermenter were: inoculum quantity of 3.5%, yak milk additive quantity of 40%, sucrose additive quantity of 4%, oligogalactose additive quantity of 3%, fermentation time of 6.5 h, fermentation temperature of 42 ℃, and sensory scores of the resultant yak yoghurt and the evaluation of the quality effect, which were higher than those of the traditional yak yoghurt, which further improved the This will further improve the acceptance of consumers and promote the development and utilisation of yak dairy products in Qinghai Plateau region.