Comparison of de-skin pretreatment and oil extraction on aflatoxins, phthalate esters, and polycyclic aromatic hydrocarbons in peanut oil

Abstract Peanut oil is a traditional high-end food oil, and most consumers enjoy fragrant peanut oil because of its unique flavor. In this paper, crude peanut oils were obtained from skinned and de-skinned peanut kernels by solvent extraction, cold pressing or hot pressing, and then, the contents of aflatoxins (AFs), phthalate esters (PAEs), and polycyclic aromatic hydrocarbons (PAHs) in raw peanut materials and their corresponding crude oil were determined. The results showed that the pressed oil had higher AFs and PAHs than leached (solvent-extracted) oil; in contrast, PAEs were higher in leached oil. Because some PAHs can be produced during roasting and the lipophilic capability of PAEs will increase at high temperature, the PAHs and PAEs of hot pressed oil are higher than those of cold pressed oil. AFs in hot pressed oil were lower than those in cold pressed oil. After removing the peanut seed coat, the contents of AFs and PAEs in the extracted oil decreased, indicating that the de-skin treatment of oilseeds can reduce the content of AFs and PAEs in the oil.