Impact of fractionation on fatty acids composition, phenolic compounds, antioxidant characteristics of olein and super olein fractions of flaxseed oil

Abstract

Flaxseed oil was fractionated at −40°C, filtrate was designated as olein fraction (31% yield), which was further fractionated at −60°C, and filtrate was named as super olein fraction (17% yield). Flaxseed oil, olein, and super olein fractions were stored at 25°C–30°C for the duration of 90 days. Alpha linolenic acid in flaxseed oil, olein, and stearin fraction was 55.26%, 63.47%, and 71.61%. High‐performance liquid chromatography (HPLC) characterization showed that phenolic compound was concentrated in olein and super olein fractions. In super olein fraction of flaxseed oil, concentration of gallic acid, protocatechuic acid, 4‐hydroxybenzoic acid, syringic acid, p‐coumaric acid, and ferulic acid was 8.14, 40.59, 75.38, 7.95, and 9.27 mg/100 g. Total phenolic contents of flaxseed oil, olein, and super olein were 145, 185, and 247 mg GAE/100 g. Peroxide value of 90 days stored flaxseed oil, olein, and super olein was 0.59, 0.75, and 0.96 (MeqO2/kg) with no difference in color and flavor scores. Practical applications Several fractions of palm oil and milk fat are commercially produced for large number of industrial applications. However, fractionation of flaxseed oil is not previously performed, and chemical characteristics of olein and super olein fractions of flaxseed oil are not reported in literature. In this study, olein and super olein fractions of flaxseed oil were produced by dry fractionation. Super olein fraction revealed more than 70% alpha linolenic, higher magnitude of phenolic compounds than parent flaxseed oil, with reasonable oxidative stability and acceptable sensory attributes. Olein and super olein fraction of flaxseed oil may be conveniently used for the supplementation of large number of food products.

Fatty acids profile, antioxidant properties, phytosterols, induction period, and sensory characteristics of olein and super olein fractions of date seed oil

“…Chia oil, its olein, and stearin fractions were characterized by phenolic compounds, and OF showed the highest content of phenolic compounds followed by chia oil and stearin fraction (Ullah et al, 2016). Azad et al (2021) produced OF and SOF from flaxseed oil, and the same were characterized for phenolic compounds on HPLC, it was reported that phenolic compounds were concentrated in OF and SOF flaxseed oil. OF and SOF of palm oil showed more content of phenolic compounds than substrate palm oil (Kumar & Krishna, 2014).…”

“…The higher induction period of OF and SOF of date seed oil was due to the presence of antioxidant substances in higher concentrations; further, the lower induction period of winterized sunflower, soybean, canola, cotton seed, and safflower oils was due to the loss of tocopherols and other antioxidant compounds during refining and bleaching, etc. The induction period of OF and SOF of date seed oil was determined on Rancimat, parent flaxseed seed had the highest induction period followed by OF and SOF, respectively (Azad et al, 2021). Ullah et al (2016) described that the induction period of OF of chia oil was lower than parent chia oil and its stearin fraction.…”

“…For example, palm olein and super olein are commercially produced from palm oil through dry fractionation (Azeem et al, 2015). Flaxseed oil was winterized at two different temperatures to produce olein and super olein, fractions had lower melting point, different fatty acids profile, higher total antioxidant capacity, and sterol contents as compared to flaxseed oil (Azad et al, 2021). The color of date seed oil is pale yellow, it can be used after the first press without refining, bleaching, and deodorization.…”

Fatty Acid Composition, Phenolic Compounds, Phytosterols, and Lipid Oxidation of Single- and Double-Fractionated Olein of Safflower Oil Produced by Low-Temperature Crystallization

“…6 The phospholipid content was significantly influenced by technological methods applied during oil extraction. 8 Triglycerides and fatty acid profiles of oils and fat can be modified to a great extent by technological methods or fat modification strategies such as chemical/ enzymatic interesterification, transesterification, blending, and low-temperature crystallization/winterization/fractionation. Among the listed techniques, low-temperature crystallization/ fractionation is one of the most commonly used methods as versions of oils and fat modified by this method can be used in the production of traditional foods and the development of functional foods.…”

“…Among the listed techniques, low-temperature crystallization/ fractionation is one of the most commonly used methods as versions of oils and fat modified by this method can be used in the production of traditional foods and the development of functional foods. 8 Modification of fats can be achieved via solvent and low-temperature crystallization; however, the latter is more suited for the food industry as the fats and oils modified by the former method may have residues of hazardous solvents used for fractionation. 9 Hussain et al 10 produced olein and super-olein fractions of date seed oil by the dry crystallization method.…”