Formation of acrylamide in heated potato products - model experiments pointing to asparagine as precursor

Model experiments were carried out to examine the mechanism of acrylamide formation in heated foodstuff, especially in potato products. For this purpose various substances, like organic acids, sugars and amino acids were heated using starch or silica gel as carrier substances. Low amounts of acrylamide are formed by heating ascorbic acid with an additional nitrogen source like ammonium acetate or glutamine. Significantly higher yields of acrylamide are formed by heating asparagine. The amount of acrylamide dramatically increases if asparagine is heated in the presence of glucose or fructose. Asparagine works not only as a nitrogen source, it seems to be evident, that the complete backbone of the acrylamide molecule is formed from asparagine. There are indications, that in an analogue reaction 3-buteneamide is formed, if glutamine is heated in the presence of reducing sugars.