Investigations of different sources of acrylamide formation in model systems consisting of amino acids and sugars have indicated the presence of two pathways of acrylamide generation; the main pathway specifically involves asparagine to directly produce acrylamide after a sugar-assisted decarboxylation step, and the second, nonspecific pathway involves the initial formation of acrylic acid from different sources and its subsequent interaction with ammonia and/or amines to produce acrylamide or its N-alkylated derivatives. Aspartic acid, beta-alanine, and carnosine were found to follow the acrylic acid pathway. Labeling studies using [(13)C-4]aspartic acid have confirmed the occurrence in this amino acid of a previously proposed sugar-assisted decarboxylation mechanism identified in the asparagine/glucose model system. In addition, creatine was found to be a good source of methylamine in model systems and was responsible for the formation of N-methylacrylamide through the acrylic acid pathway. Labeling studies using creatine (methyl-d(3)) and (15)NH(4)Cl have indicated that both the nitrogen and the methyl groups of methylamine had originated from creatine. Furthermore, analysis of cooked meat samples has also confirmed the formation of N-methylacrylamide during cooking.