Supercritical CO₂ extraction in chia oils production: impact of process duration and co-solvent addition

This study was conducted to show impact of supercritical fluid extraction using pure SC-CO₂ or SC-CO₂ enriched by 2, 6, and 10% of acetone, simultaneously varied by the extraction time (1 vs. 5 h), on the quality of chia seed oils. Obtained oils were relatively similar in the fatty acid composition, but they differed in total content of phytochemicals (from 4956 to 6391 mg/kg of oil). Among them, three oils were the most different: oil extracted 1 h with pure SC-CO₂ (the most abundant in squalene, sterols, and tocopherols), oil extracted 5 h with pure SC-CO₂ (the poorest in squalene, polyphenols, and carotenoids, with medium level of sterols and tocopherols) and oil extracted 1 h with SC-CO₂ enriched by 10% acetone (the most abundant in polyphenols and carotenoids). Such unique chia oils can be valuable for special market needs, such as cosmetics, pharmaceuticals, functional food or diet supplement production.