Acrylamide formation mechanisms

The formation of acrylamide via the Maillard pathway at temperatures typically above 120°C is today the most prominent route of formation. The key precursor of acrylamide, asparagine, provides the chemical backbone of acrylamide, in essence through decarboxylation and loss of a nitrogen moiety. Stable isotope-labeled experiments conducted in model foods have corroborated the asparagine pathway, as well as studies on the use of the enzyme asparaginase as a mitigation approach, that have resulted in the successful reduction of acrylamide across many food categories. The chemistry involved has demonstrated different possible intermediates (decarboxylated Amadori product, 3-aminopropionamide) en route to acrylamide, partly driven by the structures of the reacting carbonyls (reducing sugars or dicarbonyl compounds). Recently, 5-hydroxymethylfurfural was demonstrated as a key reactant in the formation of acrylamide, in some cases as efficient as reducing sugars in terms of acrylamide yield when using model systems. Techniques such as mass spectrometry and Fourier-transform infrared spectroscopy have aided to detect and measure the key intermediates. Lower-temperature reactions have also been proposed; for example, in the formation of acrylamide in prune concentrates heated over a longer period of time and subject to drying at a relatively low temperature (<100°C).