Development and validation of a quantitative spectrophotometric method to detect the amount of carbon monoxide in treated tuna fish

► Method for the quantitative determination of CO in the meat drip of tuna fish by UV-Vis spectroscopy. ► Evaluation of the accuracy of the method in terms of trueness and precision using fortified samples. ► Comparison with a head space gas chromatographic technique (HS-GC-MS). ► The CO levels by UV-Vis are substantially lower than those revealed by HS-GC-MS. ► For a routine analysis the spectrophotometric method is simpler and more rapid.