Occurrence of Histamine Forming Bacteria and Histamine in Dried Fish

Natural spoilage of protein rich foods leads to the production of histamine, which is associated with histamine poisoning throughout the world. Fish and fish products are at times associated with major concern due to the presence of histamine, which at toxic level generates histamine or scombroid poisoning known to be contaminated with high levels of histamine leading to histamine poisoning. Histamine consumption is also considered to be of health concerns at chronic levels due to effects on the physiological functions. Dried fish are known to be one of the most popular fish products consumed in the Indian subcontinent, often prepared under unhygienic conditions. In this present study, fifteen dried fish sold in local retail markets were purchased and screened to determine the occurrence of histamine and histamine-forming bacteria. The levels of pH, salt, moisture content and Aerobic Plate Count (APC) were determined in all samples and ranged from 5.46 to 7.07, 0.5 to 1.19%, 33 to 77.05% and 10.5 to 11.4 log CFU/g respectively. Two strains of Enterobactercancerogenous PUFSTFMDf01 and Enterobacter sp., PUFSTFMDf02 were identified as histamine forming bacteria in dried fish samples. All fifteen dried fish samples contained an average histamine content of 10.03 mg/100 g which is greater than the guideline value (5 mg/100 g) suggested by USFDA.