Journal of food science and technology(Iran)

Journal of food science and technology(Iran)

Enrichment of Essential Omega-3 Fatty Acids from Flaxseed Oil Using Urea Complexation and Cold Crystallization

Document Type : Original Article

Authors
Mahboobeh Zare 1
Mahmoud Kiani 2
Razieh Azimi 3
Seyed Ali Andi 2
1 AMOL UNIVERSITY
2 Faculty of Medicinal Plants, Amol University of Special Modern Technologies, Amol, Iran.
3 Department of Medicinal Plants and Byproducts Research, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran.
10.48311/fsct.2026.118159.82978
Abstract
Flaxseed (Linum usitatissimum) oil is an abundant botanical source of essential fatty acids (EFAs), notably α-linolenic acid (ALA, ω-3) and linoleic acid (LA, ω-6), both of which are associated with a range of health benefits. In this study, two polyunsaturated fatty acid enrichment techniques i.e., urea complexation and low-temperature crystallization (LTC), were comparatively evaluated for their effectiveness in enriching EFAs from flaxseed oil. Fatty acid profiles of crude and processed fractions were determined by gas chromatography (GC-FID), and recovery yields were calculated to assess process efficiency. The crude oil contained 54.13% ALA, 15.02% LA, 19.36% oleic acid, and 10.5% saturated fatty acids (SFAs), with total EFAs comprising 69.15% of the profile. Urea complexation resulted in a non-urea-complexed fraction (NUCF) enriched to 63.0% ALA and 17.0% LA, while reducing SFAs to 1.9%. However, the overall recovery yield was relatively low, with 23.0% recovered in the NUCF and 14.4% in the urea complexed fraction (UCF), totaling 37.4% mass retention. Conversely, LTC yielded a liquid fraction containing 55.2% ALA and 15.25% LA, with SFAs reduced to 6.62%. This method achieved a markedly higher recovery yield, with 75% of the mass retained in the liquid phase and 21% in the crystalline phase, corresponding to an overall recovery of 96%. This work provides the first direct comparative evaluation of these methods for the selective enrichment of EFAs from flaxseed oil, highlighting a critical trade-off between compositional purity and material recovery and offer evidence-based guidance for selecting enrichment strategies tailored to specific industrial or nutraceutical objectives.
Keywords
Flaxseed, &alpha
-linolenic acid, Linoleic acid, Omega-3, Linum usitatissimum
Subjects
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