# A comprehensive review on the formation and mitigation of polycyclic aromatic hydrocarbons (PAH4) in edible oils: From oilseeds to oils

## TL;DR

This review explores how harmful PAH4 compounds form in edible oils and suggests ways to reduce them during production and cooking.

## Contribution

The paper systematically reviews PAH4 formation mechanisms and mitigation strategies in edible oils from oilseeds to final products.

## Key findings

- High-temperature cooking methods increase PAH4 levels through lipid oxidation and thermal decomposition.
- Refining processes and cold pressing can effectively reduce PAH4 concentrations in oils.
- Antioxidants during processing and cooking help mitigate PAH4 formation.

## Abstract

Edible oils are susceptible to contamination by polycyclic aromatic hydrocarbons (PAHs), particularly PAH4 compounds, which include Benz [a]anthracene, Chrysene, Benzo [b]fluoranthene, and Benzo [a]pyrene, all of which are recognized for their toxic and carcinogenic properties. This review examines the mechanisms underlying the formation of PAH4 in edible oils, with a particular focus on the transformation process from oilseeds to oils. Factors influencing the formation of PAH4 include environmental contamination, the composition of fatty acids, and processing methods such as extraction, refining, and cooking. High-temperature techniques, including roasting, frying, grilling, and baking, facilitate PAH4 formation through lipid oxidation and thermal decomposition. Conversely, low-temperature and short-duration treatments, such as cold pressing, along with refining processes, effectively reduce PAH4 levels in oils. Although detection methods such as High-Performance Liquid Chromatography (HPLC) and Gas Chromatography-Mass Spectrometry (GC-MS) are reliable, they are also costly and time-consuming. In contrast, methods such as fluorescence spectroscopy, electrochemical sensors, and Surface-Enhanced Raman Scattering (SERS)-based optical sensors are more appropriate for on-site rapid detection. To reduce PAH4 concentrations, it is advisable to select raw materials with minimal contamination, utilize cold pressing or refining techniques during processing, and choose oils that are low in polyunsaturated fatty acids. Additionally, employing low-temperature cooking methods, such as steaming or boiling, is recommended. The incorporation of antioxidants during both processing and cooking can further mitigate PAH4 levels. This systematic review offers specific guidance for oils production and food safety monitoring, thereby enhancing the safety and quality of edible oils in the market.

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•PAH4 formation in oils is closely related to fatty acid composition.•High-temperature increases PAH4 levels via lipid oxidation and thermal decomposition.•Refining processes effectively reduce PAH4 levels in oil.•Antioxidants can effectively reduce PAH4 formation.

PAH4 formation in oils is closely related to fatty acid composition.

High-temperature increases PAH4 levels via lipid oxidation and thermal decomposition.

Refining processes effectively reduce PAH4 levels in oil.

Antioxidants can effectively reduce PAH4 formation.