Contents of free histidine and histamine in fish meals and in the model compounds and their toxicities to induce gizzard erosion.

: Whole meal produced from fresh sardine had a high content of histidine, while that from rancid fish had a high content of histamine. The toxicity to induce gizzard erosion, which appeared after heating, was stronger in the former whole meal than in the latter. Thus, the content of histidine, not that of histamine, was well correlate to the degree of toxicity of the heated fish meal. Changes in the contents of histidine and histamine were also studied in model compounds during heating.