In this study, biogenic amine content in two types of fermented radish kimchi (Kkakdugi and Chonggak kimchi) was determined by high performance liquid chromatography (HPLC). While most samples had low levels of biogenic amines, some samples contained histamine content over the toxicity limit. Additionally, significant amounts of total biogenic amines were detected in certain samples due to high levels of putrefactive amines. As one of the significant factors influencing biogenic amine content in both radish kimchi, Myeolchi-aekjoet appeared to be important source of histamine. Besides, tyramine-producing strains of lactic acid bacteria existed in both radish kimchi. Through 16s rRNA sequencing analysis, the dominant species of tyramine-producing strains was identified as Lactobacillus brevis, which suggests that the species is responsible for tyramine formation in both radish kimchi. During fermentation, a higher tyramine accumulation was observed in both radish kimchi when L. brevis strains were used as inocula. The addition of Myeolchi-aekjeot affected the initial concentrations of histamine and cadaverine in both radish kimchi. Therefore, this study suggests that reducing the ratio of Myeolchi-aekjeot to other ingredients (and/or using Myeolchi-aekjeot with low biogenic amine content) and using starter cultures with ability to degrade and/or inability to produce biogenic amines would be effective in reducing biogenic amine content in Kkakdugi and Chonggak kimchi.
Keywords: Chonggak kimchi; Kkakdugi; Lactobacillus brevis; biogenic amines; kimchi; lactic acid bacteria; radish kimchi; tyramine.