Effect of Extraction Methods on Quality Characteristics of Chia Seed Oil

Chia seed oil was extracted from Chia seeds by pressing method,solvent extraction method,water enzymatic method and supercritical CO₂ extraction method. The physicochemical properties,fatty acid composition,quality characteristics such as oxidative stability of oils,phenolic substances and antioxidant capacity in vitro of Chia seed oil were extracted by different methods. The results showed that among the four methods,the supercritical CO₂ extraction method had the highest oil yield(85.5%),followed by the solvent extraction method(65.8%)and the pressing method(40.9%),and the lowest water enzymatic method(33.2%). The supercritical CO₂ extraction of Chia seed oil had the best quality,the color was Y70R4.3N0.3,the acid value was 1.10 mg KOH/g,the peroxide value was 0.0137 g/100 g,and the total mass fraction of unsaturated fatty acids was 88.22%. Linoleic acid content was 18.36%,linolenic acid content was 69.86%,The oxidation rate was the slowest after 30 h,and the peroxide value reached 0.25 g/100 g,the total phenol content was 106.45 mg/kg,and the flavonoid content was 222.09 mg/kg. Supercritical CO₂ extraction of Chia seed oil at the same concentration of DPPH free radical scavenging capacity(IC₅₀ 28.04 mg/mL)and ABTS⁺· scavenging capacity(IC₅₀ 33.70 mg/mL)was superior to pressing,solvent extraction and the water enzymatic method,the superoxide anion radical scavenging ability(IC₅₀ 10.08 mg/mL)was superior to the solvent extraction method and the water enzymatic method,which was slightly lower than the pressing method.