Characteristics Of Histamine Production On Lactic Acid Bacteria Isolated From Marinade Broth In Shimesaba Production

To investigate the conditions for histamine production on lactic acid bacteria isolated from a marinade broth accumulating histamine in shimesaba production, the characteristics of growth and histamine production in the isolates were studied. Nineteen strains capable of producing histamine were isolated from a marinade broth by using the aerobic plate count with anaerobic culture method and the members of lactobacilli were identified based on the phenotypic characteristics. The closest phylogenetic neighbor of the strains was Lactobacillus otakiensis sharing 100% similarity based on 16S rRNA gene sequence. The strains harbored a pyruvoyl dependent histidine decarboxylase gene. Growth of the strains was inhibited by low pH (below 3.6), low water activity (below 0.939), high salt concentration (above 10%), and supplementation of 2% acetic acid (final concentration). However, all of the strains were able to grow in MRS broth of pH 5.7 at below 8 degrees C and produce histamine within 4 weeks of cultivation. To prevent histamine accumulation in shimesaba production, it is necessary to apply a combination of bacteriostatic conditions, low pH (around 4.0), low temperature (below 8 degrees C), and an appropriate concentration of vinegar, to preserve marinade broth based on the hurdle technology theory.