Atlantic Salmon Average Fat Content Estimated by Near‐Infrared Transmittance Spectroscopy

Near‐infrared transmittance spectroscopy was used to determine the average fat content in farmed Atlantic salmon fillets with skin and scales. The fat content was 5.7–17.6% and weight range 1.0–5.4 kg. A partial least square regression including 43 salmon resulted in a multivariate prediction correlation of 0.97 and a root mean square error of cross validation of 0.75%. Regression models using 6 to 9 wavelengths in the 850–1048 nm range gave somewhat lower prediction errors than a model using 100 wavelengths. Results showed that NIR transmittance was suited to determine fat content nondestructively in whole salmon fillets with skin and scales.