Effect of Partially Purified Extracellular Serine Proteinases Produced by Brevibacterium linens on the Accelerated Ripening of Cheddar Cheese

The effectiveness of serine proteinases produced by Brevibacterium linens (a major component of the surface microflora in surface ripening cheese) in accelerating Cheddar cheese ripening was compared with commercial bacterial metalloproteinase (Neutrase). Two partially purified fractions (Pro-C and Pro-D-E) of serine proteinase, which were rather unstable in acidic buffer, were stable in cheese and accelerated cheese ripening without causing bitterness. After 2 mo of ripening at 12T, Cheddar cheese flavor increased significantly, as scored by sensory analysis in the cheeses dosed with as much as 26 unitsfkg curd of Pro-C and Pro-D-E. No significant difference in casein hydrolysis during the ripening was observed in serine proteinases (Pro-C, Pro-D-E) and the metalloproteinasetreated cheese.