Characterization of Microbial Diversity and Chemical Properties of Cheddar Cheese Prepared from Heat-treated Milk. Cheddar cheese

This study aimed to characterize the interaction of microbial diversity and chemical properties of Cheddar cheese after three different heat treatments of milk; low temperature/long time (LTLT), thermization, and high temperature/short time (HTST). Cheese obtained from LTLT-treated milk (LC) and thermized milk (TC) had diverse bacterial community patterns, while cheese from HTST-treated milk (HC) had the lowest microbial diversity. Although the proportion of subdominant species was <1%, significant differences in community patterns were observed. Particularly, the proportions of Lb. casei and Lb. delbrueckii in LC and TC were significantly greater than in HC. Moreover, the result of chemical analysis revealed the highest proteolytic and lipolytic activities in TC. Consequently, Cheddar cheese was characterized by bacterial communities in low abundance. Furthermore, diversity of these bacterial communities is highly correlated with the heat treatment of milk and has the potential to alter chemical metabolism involved in lactose, fat, and protein during ripening.