Optical fibre-based micro-analyser for indirect measurements of volatile amines levels in fish

Abstract

An analytical method based on optical fibre (OF) detection has been developed and validated for monitoring of trimethylamine (TMA) and dimethylamine (DMA) in fish handling environments and for non invasive assessment of fish quality. The OF analyser was first calibrated and then its analytical performance for TMA and DMA was compared with a more classical method, namely gas chromatography coupled with a flame ionisation detector (GC–FID), regarding analysis of air samples from confined atmospheres. The estimates of the lower and the upper detection limit of the proposed method were found to be less than 2.2 and 18.1 μg/L for TMA and DMA. The analytical system was applied to air monitoring in a confined environment in a fish market, revealing a suitable compact design and a high analytical performance for monitoring TMA and DMA, both in situ and in real-time mode. Furthermore, the fish quality was evaluated by correlating TMA in fish tissue and in air samples from an experimental chamber containing sardines.