Fractionation of chia oil for enrichment of omega 3 and 6 fatty acids and oxidative stability of fractions

Omega 3 and 6 fatty acids were enriched in the olein fraction of chia oil via dry fractionation at -30°C. Concentrations of C18:3 (linolenic acid, ω-3) and C18:2 (linoleic acid, ω-6) were 78.16 and 25.42% in the olein fraction. HPLC characterization indicated enrichment of caffeic and chlorogenic acids, quercetin, and phenolic glycosides in the olein fraction. Total antioxidant activities of chia oil and the olein and stearin fractions were 42.5, 53.8, and 34.6%, respectively. After 6 months of storage at 4°C, the concentration of ω-3 in the olein fraction decreased from 78.19 to 76.16%, with a 10% decrease in the ω-3 concentration when the olein fraction was stored at 25°C. The stearin fraction of chia oil exhibited the longest induction period, followed by chia oil and the olein fraction. Amounts of ω-3 and 6 fatty acids can be enriched in the olein fraction from 11.92 and 61.28% to 15.22 and 72.16%, respectively, with reasonable storage stability at low temperature.