Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry.

A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were determined by use of this sample preparation method and for samples chewed for 10 s. Effects of sampling time, temperature, and purge flow on level of volatiles were tested. Purging at 340 mL/min for 30 min at 45 degrees C was found to be optimal. Detection limits for a number of aldehydes were 0.2-2.7 microg/kg. Levels of volatiles are given for fresh salmon, cod, saithe, mackerel, and redfish.