Histamine levels in imported scombroid fishes

ABSTRACT

A total of 100 imported scombroid fish samples, 50 of each frozen mackerel and canned tuna, were used in this study for determination of pH value, histamine content as well as isolation of histamine producing bacteria. pH values in imported frozen mackerel ranged from 5.4 to 6.8 with a mean value of 6.1, while they ranged from 5.6 to 6.8 with a mean value of 6 in canned tuna. 86% of mackerel samples and 16% of canned tuna showed that histamine content exceeded the permissible level [10 mg/100 g], while 10% of imported frozen mackerel and 2% of canned tuna exceeded 25 mg/100 g. None of the examined samples reached the hazard action level of histamine [50 mg/100 g]. Proteus species, followed by Klebsiella pneumoniae and Enterobacter aerogenes could be detected in high frequency as compared with other isolated organisms. The health hazard effect of histamine and suggestive measures for reducing the risk were discussed