Acrylamide Formation Mechanism in Heated Foods

TLDR

Acrylamide, a potential human carcinogen detected in foods, has spurred research into its formation mechanisms. The study proposes a mechanism for acrylamide formation from asparagine reacting with carbonyl compounds during typical cooking temperatures. The mechanism proceeds via a Schiff base intermediate that decarboxylates and eliminates ammonia or a substituted imine under heat to produce acrylamide. Isotope labeling and mass spectrometry confirm key intermediates, and asparaginase removal of asparagine reduces acrylamide levels in heated food, supporting the proposed mechanism.

Abstract

Recent findings of a potential human carcinogen, acrylamide, in foods have focused research on the possible mechanisms of formation. We present a mechanism for the formation of acrylamide from the reaction of the amino acid asparagine and a carbonyl-containing compound at typical cooking temperatures. The mechanism involves formation of a Schiff base followed by decarboxylation and elimination of either ammonia or a substituted imine under heat to yield acrylamide. Isotope substitution studies and mass spectrometric analysis of heated model systems confirm the presence of key reaction intermediates. Further confirmation of this mechanism is accomplished through selective removal of asparagine with asparaginase that results in a reduced level of acrylamide in a selected heated food.