Size‐Exclusion HPLC Separation of Bitter and Astringent Fractions from Cheddar Cheese Made with Added Lactobacillus Strains to Accelerate Ripening

Lactobacillus strains were added as an adjunct to the regular lactic starter in Cheddar cheese manufacture in order to accelerate ripening. Microbial cheese proteolysis resulted in the release of free amino acids which were extracted with the astringent and bitter fractions and separated by size‐exclusion and reversed‐phase HPLC chromatography. Lactobacillus strains generally increased the degree of proteolysis. L. plantarum and L. brevis produced off‐flavors possibly due to an accumulation of medium‐size peptides. The control cheese (without lactobacilli) had the most peptides with a mean molecular‐ weight of < 1000 daltons and had a flavor described as slightly bitter. Addition of L. casei‐casei L2A accelerated ripening and yielded a well‐aged Cheddar cheese without any bitterness even after 7 months at 6°C.