Decomposition of trimethylamine oxide during iced storage of blue whiting (Micromesistius poutassou)

Products of the decomposition of trimethylamine N-oxide (TMAO) during iced storage of blue whiting were monitored over 15 days. Increasing amounts of trimethylamine (TMA) and dimethylamine (DMA) were found in the white muscle with increasing storage time. The production of TMA was interpreted as a c onsequence of bacterial growth, while DMA production was due to enzymatic a ctivity of trimethylamine N-oxide demethylase (TMAOase). TMAOase activity w as monitored with time in different organs. The highest activities always c orresponded to kidney and spleen. Also, TMAOase was found to remain active during the 15 days of iced storage. A relationship was found between TMAOas e in kidney and DMA concentrations in white muscle.