Formation of Unsaturated Aldehydes in Edible Oils During Heating and Storage and Their Control Strategies: A Review

The safety of edible oils is of significant concern to consumers. However, heating/storage of edible oils can induce fatty acid oxidation, resulting in the formation of unsaturated aldehydes. These compounds can induce genotoxicity and carbonyl stress. We found that unsaturated aldehydes are formed through fatty acid chain reactions with hydroperoxides as key intermediates, and these aldehydes can form adducts with biomolecules, resulting in genotoxicity. Subsequently, this paper reviews the types and quantities of unsaturated aldehydes generated during the heating/storage of edible oils. The results indicate that the types of unsaturated aldehydes are related to the fatty acid composition, while their levels increase with higher heating/storage temperatures and prolonged durations. Finally, this paper summarizes current methods aimed at reducing unsaturated aldehydes in edible oils. The study shows that certain phenolic compounds and amino acids with antioxidant groups are more effective than vitamin E in reducing unsaturated aldehyde formation, making them highly promising novel antioxidants for edible oils. Moreover, current research focuses on approaches like low-temperature oil deodorization and aldehyde-absorbing packaging development to further reduce unsaturated aldehyde formation. For consumers, adopting vacuum frying and light-protected low-temperature storage can effectively minimize unsaturated aldehyde production during end-use.