CHAPTER 9: Application of Molecular Spectroscopy and Chromatography in Combination with Chemometrics for the Authentication of Cod Liver Oil

Cod liver oil (CLO) is a fish oil commonly used in pharmaceutical and food supplement products. CLO is acknowledged as a functional oil owing to its capability to provide some health benefit effects. It is known as a good source of vitamins and essential fatty acids, especially omega-3 (ω-3) and omega-6 (ω-6) fatty acids such as eicosapentaenoic acid (EPA, C_20:5 ω-3) and docosahexaenoic acid (DHA, C_22:6 ω-3), hence it commands a high price in the fats and oils industry. Some analytical methods for the authentication of CLO have been reported, including Fourier transform infrared spectroscopy, NMR spectroscopy, and chromatography-based methods. These methods in combination with chemometric techniques were successful for the identification and classification of CLO and CLO adulterated with other animal fats and vegetable oils having a lower price than CLO.