Oils and fats are important for food preparation or as ingredients in food. Crude oils and fats may contain the following contaminants: pesticide residues, polycyclic aromatic hydrocarbons, hydrocarbons of mineral origin and mycotoxins. The risk for presence of a contaminant in a crude oil depends on practices applied in the specific oil and fat supply chain. These risks are classified in a crude oil risk matrix; this matrix can be used to determine the frequency of contaminant analyses.
Crude oils are normally refined before food use to improve taste and appearance. This refining process also reduces the levels of most of the contaminants. Contaminant levels below legal limit or industry standard can be assured by combination of crude oil analyses and refining process validation.
The refining process itself may also result in the formation of process contaminants. The best-known example is trans fatty acids formed during high temperature deodorization. 3-MCPD and glycidyl esters have also been recently reported as undesirable side reaction products.
The provided contaminant levels and process validation information are summarized in an HACCP study.