A number of S. thermophilus isolates produced BA in lysine
decarboxylase broth (LDB; Table 1). Ammonia production by Streptococcus
isolates was generally above 100 mg/L in LDB. Only one
isolate of S. thermophilus accumulated high amounts of ammonia
(1602 mg/L). S. thermophilus and Lb. plantarum were found to produce
678 and 616 mg/L of ammonia in tyrosine decarboxylase
broth, respectively (Kuley & Ozogul, 2011).