Assessment of subcritical propane, supercritical CO2 and Soxhlet extraction of oil from sapucaia (Lecythis pisonis) nuts

The extraction of sapucaia (Lecythis pisonis) nut oil (SNO) using subcritical propane (SPE) and supercritical CO2 (with ethanol as co-solvent; scCO(2)) as solvent was investigated and compared with the conventional (Soxhlet) extraction. Extraction with scCO(2) was performed at 333 K and 20 MPa while the SPE extractions were carried out in different conditions to investigate the effects of temperature (293-333 K) and pressure (2-10 MPa) on the oil yield and the chemical compositions of the products. Results show that SPE allowed a fast extraction with a higher yield (46.22%) obtained at 333 K and 10 MPa, representing 93% efficiency compared to Soxhlet. Only temperature had significant (p < 0.05) effect on the extraction yield. SPE yielded the oils with highest values of polyunsaturated fatty acids (similar to 36%). Stability to oxidation ranges from 6.53 to 11.17 h. The major triacylglycerols present in SNO are OOO, SOO, POO, PLO, and POS.