Quality characteristics of Cheonggukjang by mixed culture of biogenic amine producing- and degrading-bacteria

Abstract

The objective of this study was to evaluate biogenic amine (BA) formation and degradation abilities of Bacillus strain and lactic acid bacteria (LAB) isolated from meju and doenjang and to determine the microbiological and physicochemical qualities of Cheonggukjang prepared by mixed culture of these strains. Accumulation of cadaverine (421.7 ± 11.0 mg/L) and histamine (628.7 ± 24.1 mg/L) was assessed in the culture media of Bacillus subtilis MJ226 that displayed lysine and histidine decarboxylase activities. No ability to form cadaverine, histamine, putrescine, tryptamine, and tyramine by Lactobacillus acidophilus D11, L. acidophilus D38, Lactobacillus sakei D44, Lactobacillus plantarum D70, which exhibited high BA degradation ability. The amino nitrogen and free amino acid contents were significantly (p<0.05) increased in Cheonggukjang prepared by the mixed culture of LAB (L. sakei D44, L. plantarum D70, or L. pentosus D74) and B. subtilis MJ226, whereas the ammonia nitrogen and BA (cadaverine and histamine) contents were significantly (p<0.05) decreased. Consequently, it was confirmed that BA formation in Cheonggukjang prepared by starter culture of B. subtilis was effectively inhibited by the certain strains of LAB having BA-degrading ability. Key words：Bacillus, biogenic amine, Cheonggukjang, lactic acid bacteria