Physicochemical quality and oxidative stability of linseed (Linum usitatissimum) and camelina (Camelina sativa) cold‐pressed oils from retail outlets

Abstract

Cold‐pressed linseed and camelina oils have been available on the global market for many years. They are known for their high contents of polyunsaturated fatty acids (PUFAs), mainly α‐linolenic (ALA). This study aimed to evaluate the quality and oxidative stability of linseed and camelina cold‐pressed oils purchased in retail outlets in Poland. The fatty acid composition, peroxide value, acid value, anisidine value, chlorophyll pigments, carotenoid pigments, and oxidative stability of these oils were analyzed. It was found that all analyzed oils meet the standards of requirements of the Codex Alimentarius (2009) for cold‐pressed oils. The content of chlorophyll and carotenoid pigments of linseed and camelina oils was significantly different. The percentage composition of PUFAs was high in both types of oils, but it was significantly higher in linseed than in camelina oils. The results of Rancimat and PDSC tests show low oxidative stability of all tested oils, although camelina oils were more stable than linseed oils.Practical applications: Based on the study, it can be concluded that linseed and camelina oils should be included in the human diet to provide an optimal ratio of omega‐6 to omega‐3 fatty acids. The differences between tested oils of the same seed species were significant. This study shows that quick methods of testing an oils oxidative stability (Rancimat and PDSC) may be successfully applied in oil studies.The study evaluates the quality of cold‐pressed linseed and camelina oils purchased in retail outlets in Poland. The research shows a correlation (r = −0.673) between content of polyunsaturated fatty acids and oxidative stability of tested oils. Oxidative stability was determined by Rancimat test and fatty acid composition by GC‐FID.