通过单因素试验探讨不同发酵温度、固液比、接种量、初始pH和发酵时间对乳酸乳球菌固态发酵羽毛粉降解率和菌落数的影响,采用响应面试验设计优化影响羽毛粉降解率较大因素.结果表明,①随发酵温度、固体含量、乳酸乳球菌接种量、初始pH和发酵时间增加,发酵羽毛粉降解率和乳酸乳球菌菌落数呈先增后降趋势.②各因素对乳酸乳球菌菌落数影响强度顺序为:发酵时间>接种量>固液比>发酵温度>初始pH.③优化后发酵条件为发酵温度30℃,固液比6.5∶3.5,接种量7%,初始pH 6.0、发酵时间47 h.④优化条件下发酵羽毛粉实际降解率为39.22%,乳酸乳球菌菌落数为10.61 lg(cfu·g-1).试验明确乳酸乳球菌固态发酵羽毛粉最优条件,该方法是一种提高羽毛粉饲用价值的有效方式.试验填补乳酸乳球菌固态发酵羽毛粉研究空白,为开发优质、低成本蛋白饲料提供新思路.
The effects of different fermentation factors on the degradation rate and viable count of solid state fermentation in feather meal by Lactococcus lactis were explored via the single factor design,including temperature,solid-liquid ratio,inoculum,initial pH,and time of fermentation.Response surface method was introduced to optimize the influence factors of degradation rate of fermentation feather meal.The results showed as the followings:①The degradation rate and viable count exhibited a trend that first decreased and then increased with an increasing of temperature,solid-liquid ratio,inoculum,pH,and fermentation time.② The order of the importance each factor on viable count of Lactococcus lactis was fermentation time>inoculum>solid-liquid ratio>fermentation temperature>initial pH.③The optimal conditions for feather meal by Lactococcus lactis were fermentation temperature 30℃,solid-liquid ratio 6.5∶3.5,inoculum 7%,pH 6.0,and fermentation time 47 h.④After the optimization of feather meal fermentation,the degradation rate of feather meal was 39.22%,and the viable count of Lacto-coccus lactis was 10.61 lg(cfu·g-1).In conclusion,this research defined the optimal conditions of solid state fermentation in feather meal by Lactococcus lactis,and increased the feeding value of feather meal.This study filled the gap of solid state fermentation in feather meal by Lactococcus lactis and provided new insights for the development of high quality and low cost protein resource.