Polycyclic aromatic hydrocarbons in edible oils and fatty foods: Occurrence, formation, analysis, change and control

Numerous studies have demonstrated that dozens of polycyclic aromatic hydrocarbons (PAHs) are mutagenic, genotoxic and strongly carcinogenic. PAHs are found to be widely present in foods contaminated through multiple paths. Due to their lipophilic nature, these compounds easily accumulate in edible oils and fatty foods where they can range from no detection to over 2000μg/kg. Compared to precursor PAHs, researchers have seldom studied the presence of PAH derivatives, especially in food matrices. This chapter includes the physical and chemical characteristics of PAHs and their types, occurrence, sample pretreatment and instrumental determination methods, and their formation, change and control in edible oils and fatty foods. The occurrence and formation of PAH derivatives in foods are much less investigated compared to those of their precursor PAHs. Although the removal of matrix effects and accuracy remain difficult for current rapid determination methods, a prospective research direction of PAH analysis for large-scale screening is in demand. To date, physical absorption, chemical oxidation and biodegradation have been widely used in PAH removal techniques. Specific types of bacteria, fungi, and algae have also been used to degrade PAHs into harmless compounds. However, most of them can only degrade a range of LPAHs, such as naphthalene, anthracene and phenanthrene. Their ability to degrade HPAHs requires further study. Moreover, it is still a great challenge to maintain food nutrition and flavor during the PAH removal process using these methods.