Life Sciences Commons^™

Aromatic Amino Acid Catabolism By Lactobacillus Spp.: Biochemistry And Contribution To Cheese Flavor Development, Sanjay Gummalla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acids derived from the degradation of casein in cheese serve as precursors for the generation of desirable and undesirable flavor compounds. Microbial degradation of aromatic amino acids is associated with the formation of aroma compounds that impart putrid-fecal, barny-utensil, and floral off-flavors in cheese, but pathways for their production had not been established. This study investigated Tyr and Phe catabolism by Lactobacillus casei and Lactobacillus helveticus cheese flavor adjuncts under simulated Cheddar cheese-ripening conditions (pH 5.2, 4% NaCl, 15°C, no sugar). Enzyme assays of cell-free extracts and micellar electrokinetic capillary chromatography of supernatants indicated that L. casei and L. …