The Histamine Checker can be used on any kind of flesh (freshly killed or frozen), using samples taken from any tissue location.

When fish is no longer fresh, it can easily cause food poisoning. This may appear as a skin rash, which is caused by histamine present in decaying fish. This is a simple method enabling the visualization of histamine levels, allowing inspection by eye.
When red-fleshed fish, such as tuna and sardines, is no longer fresh, the histamine released can be a cause of food poisoning. Histamine extracted from fish is separated by electrophoresis, stained, and the amount present is measured by colour intensity.