Pressurized mixture of CO2 and propane for enhanced extraction of non-edible vegetable oil

Abstract

Vegetable oils in neglected matrices (monguba seeds and immature green coffee beans) were extracted using a mixture of pressurized carbon dioxide (CO2) and propane. The yields, fatty acid profiles, and active compounds in the extracted oils were evaluated employing a Box-Behnken experimental design, considering the effects of temperature (20–60 °C), solvent flow rate (1.5–2.5 mL min−1), and propane amount (10–50%). The maximum yields were 42.83% for monguba oil and 10.83% for immature green coffee oil. Lower temperature (40–60 °C) and a higher propane fraction (50%) led to higher oil yields. Empirical models satisfactorily described the extraction kinetics. Treatment of the data using principal component analysis (PCA) revealed that the conditions that favored extraction of saturated fatty acids impaired the extraction of polyunsaturated fatty acids. Extraction with a mixture of pressurized CO2 and propane resulted in attractive fatty acid profiles and high oil yields, while preserving the active compounds.