Quantitation of 3-aminopropionamide in potatoes - A minor but potent precursor in acrylamide formation

3-Aminopropionamide (3-APA) has recently been suggested as a transient intermediate in acrylamide (AA) formation during thermal degradation of asparagine initiated by reducing carbohydrates or aldehydes, respectively. 3-APA may also be formed in foods by an enzymatic decarboxylation of asparagine. Using a newly developed method to quantify 3-APA based on liquid chromatography/ tandem mass spectrometry, it could be shown that the biogenic amine was present in several potato cultivars in different amounts. Further experiments indicated that 3-APA is formed during storage of intact potatoes (20 or 35 degreesC) or after crushing of the cells. The heating of 3-APA under aqueous or low water conditions at temperatures between 100 and 180 degreesC in model systems always generated more AA than in the same reaction of asparagine, thereby pointing to 3-APA as a very effective precursor of AA. While the highest yields measured were about 28 mol % in the presence of carbohydrates (170 degreesC; aqueous buffer), in the absence of carbohydrates, 3-APA was even converted by about 63 mol % into AA upon heating at 170 degreesC under aqueous conditions. Propanoic acid amides bearing an amino or hydroxy group in the alpha-position, such as 2-hydroxypropionamide and L-alaninamide, were ineffective in AA generation indicating that elimination occurs only from the beta-position.