Abstract:In this paper, 16S rDNA sequencing and high performance liquid chromatography (HPLC) were used to analyze the effects of constant temperature and room temperature fermentation on the physicochemical properties, lactic acid bacteria and organic acids of fern kimchi. The results showed that room temperature fermentation had little effect on the pH and titratable acid of kimchi juice and sample within 7 days. The pH of both constant temperature and room temperature fermentation were decreased to 4.2 (p< 0.05), and the titratable acid increased to 0.68% and 0.65% (p<0.05), respectively. The peak value of nitrite in the kimchi under constant temperature appeared 1 d earlier than the kimchi under room temperature, and decreased to 0.68 mg/L and 0.65 mg/L on the 7 th day. The overall acceptability of sensory score showed that the room temperature-fermented kimchi (7.5) was better than the constant temperature-fermented kimchi (7.2). Leuconostoc species in the room temperature-fermented kimchi decreased the Lactobacillus / Leuconostoc ratio; the content of the lactic acidinthe constant temperature-fermented kimchi was 122.58 mg/L, while the room temperature-fermented kimchi was103.09 mg/L; their contents of acetic acid finally was 16.25 mg/Land 18.90 mg/L, respectively. The difference of lactic acid/acetic acid was also the main reason why the sensory score of room temperature-fermented kimchi was better than that of constant temperature-fermented kimchi. Lactobacillus plantarum was identified as the dominant bacteria in fern kimchi.
