T. Hofmann
Sep 26, 1998
Citations
2
Influential Citations
31
Citations
Journal
Journal of Agricultural and Food Chemistry
Abstract
Thermal treatment of a methanolic solution of N-(1-deoxy-d-fructos-1-yl)-l-proline and furan-2-carboxaldehyde led to the rapid formation of colored compounds, among which 4-hydroxy-2-methoxy-2-methyl-5-[(E)-(2-furyl)methylidene]methyl-2H-furan-3-one (1) could be identified as one of the main colored compounds by NMR, LC/MS, and UV−vis spectroscopy. Studies on its formation revealed that condensation of the hexose dehydration product acetylformoin (2a/2b) with furan-2-carboxaldehyde formed the labile 2,4-hydroxy-2-methyl-5-[(E)-(2-furyl)methylidene]methyl-2H-furan-3-one (3a/3b), which then reacts with methanol to the more stable colorant 1. Reacting furan-2-carboxaldehyde with N-(1-deoxy-d-fructos-1-yl)-l-alanine, however, completely stalled the formation of acetylformoin and, consequently, also of colorant 1. Further model studies revealed acetylformoin as a chemical switch in the Maillard reaction determining different reaction pathways in the presence of primary and secondary amino acids; for example, t...