Abstract

Mongolian cheese was sterilized by using supercritical carbon dioxide (SC–CO 2 ) treatment at three pressures (10, 15 and 20 MPa) and three temperatures (40, 50 and 60 °C). The optimum SC-CO 2 condition (20 MPa and 60 °C) could achieve complete inactivation of bacteria. Preservation of Mongolian cheese was assessed at 25 °C for 20 d by analyzing texture, bacterial communities and volatile compounds, after using SC-CO 2 (20 MPa and 60 °C). The results indicated that SC-CO 2 treatment could maintain texture stability of Mongolian cheese during storage. High throughput sequencing results showed that Clostridium_sensu_stricto and Lysinibacillus were not detected in the SC-CO 2 treated cheese and the total abundance of spoilage bacteria in the SC-CO 2 treated cheese was much lower than that in untreated cheese after 20 days storage. Nine core functional bacteria such as Clostridium_sensu_stricto , Lysinibacillus, Pseudoclavibacter, Pseudomonas, Acinetobacter , Lactococcus , Aeromonas , Serratia and Buttiauxella that significantly affected the formation of volatile compounds were identified by Spearman correlation analysis. SC-CO 2 treatment decreased the contents of volatile compounds (acids and esters) ( p  < 0.05), avoiding off-flavors development related to the volatile compounds of excess in Mongolian cheese during storage. Overall, SC-CO 2 technology could be used as an effective tool to sterilize Mongolian cheese with minimal quality changes.