Peptides as Sources of Essential Amino Acids for Lactic Streptococci

Abstract

Strains of Streptococcus lactis, Streptococcus lactis var. maltigenes and Streptococcus cremoris possess peptidases capable of hydrolyzing several synthetic di-and tripeptides, when the C-terminal amino acid was glycine or of the L-configuration. S lactis var. maltigenes degraded dipeptides containing L-leucine and L-valine to 3-methylbutanal and 2-methylpropanal, respectively, indicating a possible source of aromatic aldehydes in dairy products.