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 degrees C) or after crushing of the cells. The heating of 3-APA under aqueous or low water conditions at temperatures between 100 and 180 degrees C 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 degrees C; aqueous buffer), in the absence of carbohydrates, 3-APA was even converted by about 63 mol % into AA upon heating at 170 degrees C 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.
Granvogl
Michael
M
Lehrstuhl für Lebensmittelchemie, Technische Universität München, Lichtenbergstrasse 4, D-85748 Garching, Germany.
Jezussek
Magnus
M
Koehler
Peter
P
Schieberle
Peter
P
D020106:Acrylamide / Q000032:analysis / Q000737:chemistry*; D003653:Decarboxylation; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D011198:Solanum tuberosum / Q000737:chemistry*; D014867:Water; D015091:beta-Alanine / Q000031:analogs & derivatives / Q000032:analysis* / Q000737:chemistry
D014867:Water; D015091:beta-Alanine; D020106:Acrylamide; C012731:beta-alanine amide