Distribution of histamine-producing lactic acid bacteria in canned salted anchovies and their histamine production behavior

Histamine-producing bacteria were isolated from various types of canned salted anchovies with cooking oil, which were purchased from retail groceries over a study period of eight years. Thirty-two histamine-producing bacterial isolates were collected from 13 samples, which were equivalent to 43 % of the total canned anchovies manufactured in four different countries. All of these histamine-producing bacterial isolates were Gram-positive, catalase-negative, tetrad-forming cocci, and were identified as the lactic acid bacterium Tetragenococcus muriaticus by 16S rRNA gene sequence analysis. These findings indicated that histamine-producing T. muriaticus cells are widely distributed in the canned anchovies that were purchased from retail groceries. In addition, to evaluate the suppression of histamine production using a model of the storage condition of canned anchovies, the histamine-producing ability of our isolates under various culture conditions was examined. Low-pH and low-temperature conditions were demonstrated to be useful for inhibiting the histamine production of these isolates.