Abstract:To investigate the effects of different fermentation conditions on pH value， color difference， and sensory score of fermented Tibetan mutton sausage， Tibetan sheep meat was used as experimental material，and a lactic acid bacteria starter culture（Lactobacillus plantarum HH-LP56∶Streptococcus thermophilus HHST08 = 1∶1， mass ratio） was added. Single-factor and response surface experimental designs were carried out using pH value， color difference value， and sensory score as evaluation indices to explore the effects of strain inoculum size， fermentation time， and fermentation temperature on the quality characteristics of fermented mutton sausage and determine the optimal process conditions. The results indicated that the optimal process conditions were a fermentation temperature of 33.0 ℃， a fermentation time of 35.5 h， and a strain inoculum size of 108 CFU/g. Under these conditions， the fermented mutton sausage achieved the relatively high sensory score （75.50）， with high overall acceptance， favorable product flavor， and reliable optimization results， which contribute to research on the processing technology and quality improvement of fermented mutton sausage.