Higher Oxidative Stability of Alpha-linolenic Acid Than Linoleic Acid in Nanoemulsions: a Comparison Between Bulk Flaxseed Oil and its O/W Nanoemulsions

• Published in: Food biophysics 2021-06, Vol.16 (2), p.203-213
• Main Authors: Zeinalzadegan, Masoomeh, Nejadmansouri, Maryam, Golmakani, Mohammad-Taghi, Mesbahi, Gholam Reza, McClements, David Julian, Hosseini, Seyed Mohammad Hashem
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Biological and Medical Physics; Biophysics; Carotene; Chemistry; Chemistry and Materials Science; Corrosion resistance; Degradation; Droplets; Emulsions; Fatty acids; Flaxseed oil; Food Science; Linoleic acid; Linolenic acid; Lipid peroxidation; Lipids; Nanoemulsions; Original Article; Oxidation; Physicochemical properties; Stability; Storage temperature; Thiobarbituric acid; β-Carotene
• ISSN: 1557-1858; 1557-1866
• DOI: 10.1007/s11483-020-09662-8

In this study, the effects of different dispersed phase volume fractions ( Φ 0.025 and 0.1) and storage temperature (4 and 25 °C) were determined on lipid oxidation, fatty acids profile, β-carotene degradation, and other physicochemical properties of flaxseed oil-in-water nanoemulsions. Nanoemulsions containing small anionic droplets (≈ 100 nm) were fabricated using high-pressure homogenization. Although an increase in the viscosity and physical stability of nanoemulsions was observed with increasing Φ , but mean droplet diameter and chemical stability decreased. β-carotene degradation, free fatty acids formation, as well as thiobarbituric acid-reactive substances production, were all faster in the more concentrated emulsions. As the storage temperature raised, physical and chemical stability both decreased. Interestingly, while the ratio of α-linolenic acid to linoleic acid in bulk oil decreased over time, an opposite trend was observed in the nanoemulsions. This effect was due to differences in the location of different unsaturated fatty acids inside the oil nanodroplets.