title: Impact of the N-terminal amino acid on the formation of pyrazines from peptides in Maillard model systems.
abstract: Only a minor part of Maillard reaction studies in the literature focused on the reaction between carbohydrates and peptides. Therefore, in continuation of a previous study in which the influence of the peptide C-terminal amino acid was investigated, this study focused on the influence of the peptide N-terminal amino acid on the production of pyrazines in model reactions of glucose, methylglyoxal, or glyoxal. Nine different dipeptides and three tripeptides were selected. It was shown that the structure of the N-terminal amino acid is determinative for the overall pyrazine production. Especially, the production of 2,5(6)-dimethylpyrazine and trimethylpyrazine was low in the case of proline, valine, or leucine at the N-terminus, whereas it was very high for glycine, alanine, or serine. In contrast to the alkyl-substituted pyrazines, unsubstituted pyrazine was always produced more in the case of experiments with free amino acids. It is clear that different mechanisms must be responsible for this observation. This study clearly illustrates the capability of peptides to produce flavor compounds such as pyrazines.
authors.affiliation: Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
authors.forename: Fien
authors.initials: F
authors.lastname: Van Lancker
authors.forename: An
authors.initials: A
authors.lastname: Adams
authors.forename: Norbert
authors.initials: N
authors.lastname: De Kimpe
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D005524:Food Technology; D005947:Glucose / Q000737:chemistry; D006037:Glyoxal / Q000737:chemistry; D015416:Maillard Reaction; D008956:Models, Chemical; D009842:Oligopeptides / Q000737:chemistry*; D011719:Pyrazines / Q000032:analysis / Q000737:chemistry*; D013649:Taste
chemical_list: D000596:Amino Acids; D009842:Oligopeptides; D011719:Pyrazines; D006037:Glyoxal; D005947:Glucose