Non‐destructive determination of fat, moisture and protein in salmon fillets by use of near‐infrared diffuse spectroscopy

Abstract

Abstract Near infrared (NIR) diffuse spectroscopy was used to determine the fat, moisture and protein contents in whole and ground farmed atlantic salmon fillets. A remote fibre‐optic probe was used for NIR measurements on 50 whole salmon fillets. The constituent ranges were: 91‐205 g kg −1 fat, 599‐709g kg −1 moisture and 186‐209 g kg −1 protein. Principal component regression resulted in the following prediction errors for ground salmon fillets, expressed as root mean square error of cross validation: 6.6 g kg‐1 fat, 3.8 g kg −1 moisture and 2.0 g kg −1 protein. The corresponding prediction errors for non‐destructive measurements on whole salmon fillets were 10.8 g kg −1 fat, 8.5 g kg −1 moisture and 3.7 g kg −1 protein. Regression models using the 760‐1100 m range gave lower prediction errors than models using the 1100‐2500 mm or 760‐2500 nm ranges. The results show that fibre‐optic probe NIR instruments are suited to determine fat and moisture in whole salmon fillets non‐destructively.