Proteolysis development in enzyme-modified Cheddar cheese using natural and recombinant enzymes of Lactobacillus rhamnosus S93

摘要

Proteolysis in enzyme-modified cheese was investigated with natural crude enzyme or recombinant ami-nopeptidase, both derived from Lactobacillus rhamnosus S93 in the presence of a commercial proteinase, Neutrase. For production of enzyme-modified cheeses, a cheese slurry was produced and pre-incubated with Neutrase. Natural enzyme or recombinant aminopeptidase (50 units 200 g~(-1) slurry) was added alone or in combination to the cheese slurries, which were then incubated anaerobically under vacuum at 37 ℃ for 1,3 and 6 d. The greatest levels of phosphotungstic acid soluble nitrogen and free amino acids were observed in the enzyme-modified cheese containing natural enzyme followed by the one treated with a combination of the natural enzyme and recombinant aminopeptidase. The enzyme-modified cheese containing the recombinant aminopeptidase alone resulted in the complete disappearance of pro-line after 1 d of maturation time.