A capillary electrophoresis approach for major unsaturated fatty acids screening in milk

Abstract

Fast methods for milk analysis are internationally desired, and, in this study, a new method for milk unsaturated fatty acids (UFAs) is proposed, using capillary zone electrophoresis with direct detection in the ultraviolet region. Run time analysis was 4 min, and sample preparation comprised only a saponification reaction, which indicates the suitability of the method for UFA monitoring in routine analyses by industries and milk researchers. Milk powder samples submitted to different oxygen content (0.3–20.4%) were analysed after ten months of storage to demonstrate method applicability, aiming to evaluate differences in UFA profiles, the most prone to lipid oxidation. No significant difference was noticed within the 95% confidence interval when comparing different samples. Limits of detection (mmol L−1) for UFAs were 0.040 (C18:1 n-9 cis); 0.014 (C18:2 n-6) and 0.010 (C18:3 n-3). Limits of quantification were 0.132, 0.046, and 0.034 mmol L−1, respectively.