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Updated: Jan 13, 2026

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements
Published on: May 1, 2017
Advancing the Analysis of Fatty Acid Composition in Animal-Based Marine Oils Through the Integration of Raman and IR
Fatema Ahmmed1,2, Keith C Gordon1,2, Asli Card3
1Te Whai Ao, Dodd-Walls Centre for Photonic and Quantum Technologies and Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9016, New Zealand.
Abstract:
This study investigated the use of Raman and IR spectroscopy, individually and combined, for quantifying fatty acid methyl ester (FAME) profiles in animal-based marine oils and potential adulterants (palm oil, ω-3 concentrates in ethyl ester, and generic fish oil). FAME profiles are important for assessing oil quality, conventionally determined via gas chromatography. This study aimed to provide a rapid and non-destructive alternative. The study utilized Partial Least Squares Regression (PLSR) alongside Raman (r2 = 0.94; RMSEP = 2.4%) and IR spectroscopy (r2 = 0.95; RMSEP = 2.3%), demonstrating similar ω-3 fatty acid predictions. Fusion of IR and Raman spectroscopic datasets improved ω-3 fatty acid (r2 = 0.96; RMSEP = 1.9%), polyunsaturated fatty acids (PUFA) (r2 = 0.83; RMSEP = 4.0%), and saturated fatty acids (SFA) (r2 = 0.79; RMSEP = 4.1%) quantification. The study highlights that fusion of IR and Raman spectroscopic datasets presents a promising avenue for non-destructive fatty acid composition assessment.
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