Reducing polycyclic aromatic hydrocarbons (PAHs) formation in olive pomace oil using microwave pre‐heating of olive pomace

Abstract

High temperature application during drying of olive pomace before solvent extraction leads to formation of polycyclic aromatic hydrocarbons (PAHs) and their eventual presence in the oil. Therefore, the objective of this study was to investigate a mitigation possibility of PAHs in olive pomace oil. For this purpose, microwave pre‐treatment was applied to the olive pomace before drying at 200°C to final moisture content of less than 5%. Effect of pre‐drying microwave process was carried out against drying at 200°C and vacuum drying. PAH content analysis of the solvent extracted oil was completed using a HPLC method with fluorescence detection (HPLC‐FLD). The results demonstrated that the pre‐microwave application led to 75% reduction of total PAHs content in olive pomace oil. This study highlighted the possibility of an alternative innovative strategy to apply in a process to suggest a simple solution for a significant industrial problem.Practical applications: PAHs are serious problem in olive pomace oil. Removal of PAHs in olive pomace oil has a great importance because of their carcinogenic potential. Results show that PAHs are formed during drying of olive pomace at high temperature (200°C). This study reveals that microwave application was effective strategy to reduce PAHs in olive pomace oil. Therefore, drying process was modified with microwave pre‐heating application to produce high quality olive pomace oil.In this study, the effect of microwave pre‐heating application before drying to reduce PAH formation in olive pomace oil is demonstrated. The eventual reduction of total PAH concentration in olive pomace oil indicated the effectiveness of this pre‐heating application.