NON-ENZYMIC FORMATION OF DIMETHYLAMINE IN DRIED FISHERY PRODUCTS

Dimethylamine (DMA) forms very rapidly in heat-dried and freeze-dried fish muscle. The DMA forms regardless of species. The rate of DMA formation was related to the water activity (Aw) of the product with minimum amounts forming at Aw <1 and Aw 4. Evidence was developed to show that the formation of DMA in these products did not result from enzymic activity. In vitro studies show that several ionic constituents such as Fe2+, Sn2+, and SO2 induce the degradation of trimethylamine oxide (TMAO) to DMA. Metal chelators such as EDTA and phytic acid in the presence of Fe2+ and Sn2+ rapidly accelerate the formation of DMA. © 1979, American Chemical Society. All rights reserved.