Effect of Methionine on the Thermal Degradation of N-(1-Deoxy-D-fructos-1-yl)-methionine Affecting Browning Formation

The effect of additional DL-methionine (Met) on the thermal degradation of a methionine-glucose-derived Amadori rearrangement product (MG-ARP) was investigated under different reaction conditions. The resulting color formation and changes in the concentrations of MG-ARP, Met, and alpha-dicarbonyl compounds were investigated. Additional Met did not affect the degradation rate of MG-ARP but got involved in subsequent reactions and resulted in a decrease in the contents of C-6-alpha-dicarbonyl compounds. During MG-ARP degradation, the formation of glyoxal (GO) and methylglyoxal (MGO) was facilitated by additional Met, through retro-aldolization reaction of C-6-alpha-dicarbonyl compounds. This effect of Met addition was dependent on the reaction temperature, and the consistent conclusion could be made in a buffer system. The improvement of GO and MGO formation as color precursors caused by the additional Met contributed to the acceleration of browning formation.

Automated summary

Additional DL-methionine did not affect the degradation rate of the methionine-glucose-derived Amadori rearrangement product, but played a role in subsequent reactions, resulting in a decrease in C-6-alpha-dicarbonyl compounds and facilitating the formation of glyoxal and methylglyoxal. The effect of Met addition was dependent on reaction temperature and contributed to the acceleration of browning formation by improving the formation of color precursors glyoxal and methylglyoxal.