Effect of hot acidic fructose solution on caramelisation intermediates including colour, hydroxymethylfurfural and antioxidative activity changes

Fructose model solutions of various concentrations were adjusted to pH 3.0, then incubated at 75, 85, and 95 °C, respectively, for studying the reaction kinetics of colour development, hydroxymethylfurfural (HMF) production, and antioxidative activities change in the caramelisation reaction. Results showed that colour development, HMF production, DPPH radical scavenging activity and ABTS·+ radical scavenging activity in the system increased linearly with a first-ordered kinetics on fructose concentration. Their values of Q10 were 1.87, 4.48, 2.06, and 2.24, and activation energies were 66, 160, 77, and 86 kJ/mol, respectively.