The Potential of Raman Spectroscopy for the Classification of Fish Fillets

Abstract

Since fishery products represent an important and globally growing food resource, there is also an increased incidence rate of intentional mislabelling of fish products and restaurant frauds globally. In the present study, Raman spectroscopy, as a fast and non-invasive technique, was applied using a laser at a wavelength of 532 nm for the classification of deep frozen fish fillets. Without any preparation, muscle tissue of 12 fish types was analysed with a Raman device, and according to a hierarchical cluster analysis of their spectra, three groups were identified: (1) the carotenoid group, fish from salmonid family; (2) the freshwater group, fish that was reared in fresh or brackish water; and (3) the saltwater group, fish reared in saltwater. Thus, it is demonstrated that Raman spectroscopy can be used as a direct, non-expensive and fast screening method before proceeding with standard methods for the identification of fish fillets.