In vivo determination of fat content in Atlantic salmon (Salmo salar) with a mobile NMR spectrometer

A new method for the rapid measurement of the fat content in live (or slaughtered) Atlantic salmon, based on a mobile low-field NMR analyser, has been developed and tested. The instrument, calibrated against a set of reference samples (fish oil in agarose), was used for non-destructive fat determination of the Norwegian quality cut (NQC) of anaesthetized fish. The total analysis time per fish was about 20 s. The fat content (range 90-182 g kg(-1)) showed significant correlation (r = 0.92) with chemical extraction data obtained after slaughtering the same fish. The spatial distribution of fat in the NQC was obtained and visualized as a 'fat image' using novel software. It was concluded that the mobile NMR spectrometer has potential for implementation in connection with on-line quality control. (c) 2005 Society of Chemical Industry.