Benefits, deleterious effects and mitigation of methylglyoxal in foods: A critical review

Background: Methylglyoxal, a reactive carbonyl compound widely present in thermally processed foods, is produced from sugar degradation and lipid oxidation. Methylglyoxal can yield various aroma compounds by reacting with amino acids and act as a precursor to generate other toxins, including advanced glycation end products, acrylamide and 4(5)-methylimidazole. Scope and approach: This review highlights the formation and the transformation of methylglyoxal, its benefits and its deleterious effects as well as the interaction with dietary ingredients and scavenging reagents. Moreover, the role of amino acids and phenolic compounds in methylglyoxal mitigation in foods and the possible consequences of the intake of the derived adducts was discussed. Key findings and conclusions: The formation and the transformation of methylglyoxal simultaneously occur during food processing. Amino acids and phenolic compounds can efficiently scavenge methylglyoxal, thereby forming numerous adducts, due to their highly nucleophilic reactivity with methylglyoxal. The absorption, metabolism and toxicology of dietary methylglyoxal–phenolic adducts remain largely unknown and require further investigation before applying polyphenols to control methylglyoxal in foods. The selective addition of amino acids may provide a satisfactory strategy to control methylglyoxal in foods, but their effects on food quality and the toxicity of derived adducts should be deeply investigated.