Simultaneous Measurements of Trimethylamine and Dimethylamine in Fish, and Their Use for Estimating Quality of Frozen-Stored Gadoid Fillets

Abstract

On the basis of some of the recent modifications of Dyer's colorimetric test for measuring trimethylamine (TMA) in fish, a procedure is described that gives both the TMA and the dimethylamine (DMA) contents. Measurements on 84 frozen-stored fillets of haddock, cod, pollock, cusk, and hake showed a correlation coefficient of 0.94 between DMA values obtained by the copper–dithiocarbamate test and those obtained by the picric acid procedure. The simultaneous measurements of TMA and DMA are useful in estimating the quality of frozen-stored gadoid fillets, the TMA value indicating the extent of microbial spoilage before the muscle was frozen and the DMA value the extent of deterioration through action of tissue enzymes during frozen storage.