Investigation of Conversion of Sunflower Oil Production Wastes to High Value Compounds by Supercritical CO2

The evaluation of wastes from edible oil production industry has increasing importance because of resources deficiency and growing population day by day. It was aimed to investigate the recovery potential of oil and valuable components such as total phenolic contents (TPC), total flavonoid content (TFC) and antioxidant activities with conventional and green extraction methods from edible sunflower oil production wastes. Firstly, Soxhlet extraction was applied on the waste samples from filtration of the oil and then supercritical CO2 (SC- CO2) extraction was performed to compare extraction yield. The statistical evaluation of the SC- CO2 extraction experiments was conducted with the Minitab Software program. It was concluded that 37% extraction yield was obtained with the mixture of perlite and waste sample, while the highest recovery was observed as 27% for the perlite-free sample. The interaction of independent variables (temperature and pressure) on the recovery yields were determined as significant (p=0.002). Pressure was detected more effective on the valuable substance contents of the extracts than temperature. The most efficient conditions were 50 oC and 22.1 MPa for oil recovery, while 60 oC and 20 MPa for valuable substance recovery.