Histamineproducing

Histamine-producing refers to organisms or cells that synthesize histamine by decarboxylating histidine. Histamine is a biogenic amine involved in immune responses and gastric function. Several microbes possess histidine decarboxylase, enabling histamine production, which can accumulate in foods under improper storage or processing.

Bacterial producers include Morganella morganii, Proteus spp., Hafnia alvei, Klebsiella spp., and Providencia rettgeri, commonly linked to histamine formation in spoiled fish and other foods. Some lactic acid bacteria also carry histidine decarboxylase and can form histamine. The amount produced depends on temperature, time, pH, salt, and other factors affecting bacterial growth.

Health and safety: Ingesting histamine-rich foods can cause scombroid poisoning, with flushing, headaches, nausea, and palpitations. Individual susceptibility varies; reduced diamine oxidase (DAO) activity increases risk. Prevention relies on proper handling, rapid chilling, and good hygiene. Histamine formed during storage is heat-stable and may persist after cooking.

Detection and regulation: Food laboratories test for histamine content and may screen for histidine decarboxylase genes. Regulatory limits for histamine in fish differ by jurisdiction, typically in the tens to hundreds of milligrams per kilogram. Controlling time-temperature exposure and sanitation is central to preventing histamine production in foods.