Iron (Fe2+)-Catalyzed Glucosamine Browning at 50 degrees C: Identification and Quantification of Major Flavor Compounds for Antibacterial Activity

摘要

Glucosamine browning at 50 degrees C with (GlcN/Fe2+) or without iron (GlcN) was studied over time from 0 to 48 h. Generation of reactive oxygen species (ROS), H2O2, and O-1(2), along with alpha-dicarbonyls, fructosazine, and deoxyfructosazine, was evaluated. Singlet oxygen generation increased over time and was greater in GlcN/Fe2+ caramel solution. The presence of iron significantly increased the concentration of alpha-dicarbonyls at an early incubation time (3 h). Fructosazine and deoxyfructosazine were the major degradation products at 48 h comprising together up to 37 and 49% in GlcN and GlcN/Fe2+, respectively. GlcN/Fe2+ (48 h) exhibited a MIC50 against highly heat-resistant Escherichia coli AW 1.7 at pH 5, but not at pH 7. Despite several antimicrobial compounds being produced during browning, GlcN/Fe2+ created a synergistic environment for the fructosazine-organic acids to confer their antimicrobial activity. GlcN caramel solutions have the potential to serve as both flavoring compounds and antimicrobial agents in formulated food systems.