Interactions between polycyclic aromatic hydrocarbons (PAHs) and phospholipids cause PAH migration into wet gums during the oil degumming process

Abstract

The refining process can reduce PAH contamination levels in vegetable oils, but the safety of byproducts requires further attention. We hypothesize that interactions between PAHs and phospholipids could contribute to PAH migration into the wet gums and subsequently evaluated the distribution of PAHs during different degumming processes. Enzymatic degumming achieved over 99.90 % removal of phospholipids from soybean oil and sunflower seed oil and minimized the toxic equivalency quotient of PAHs in wet gums (approximately 0.05 μg/kg). Notably, greater PAH reduction was correlated with greater phospholipid removal in degummed soybean oil. Quantum chemical calculations indicated that van der Waals forces between PAHs and phospholipids could cause PAH migration, with higher phospholipid contents and PAH contamination in soybean oil providing more favourable conditions than in sunflower seed oil. This study will help to improve the quality of edible oils and provide information on the mechanisms underlying PAH migration.