Prediction of Proximate Fish Composition from Ultrasonic Properties: Catfish, Cod, Flounder, Mackerel and Salmon

The ultrasonic velocity within Atlantic cod (Gadus morhua), Atlantic mackerel (Scomber sombrus), Atlantic salmon (Salmo salar), Channel catfish (Ictalurus punctatus), and Sole flounder (Pseudopleuronectes americanus) fillets was measured over a range of temperatures (5 to 35°C) using an ultrasonic pulse-echo technique (～3.5 MHz). Lipid, protein, moisture and ash content of fillets were determined by standard methods. Ultrasonic velocity-temperature profiles were dependent on fish composition and could be predicted reasonably well using a semi-empirical equation developed in a previous study. Ultrasonic velocity measurements show potential for analyzing fish composition.