Revaluing Anion Effects on Maillard Reaction Catalysis as a Relevant Feature for Kinetic Predictions

The influence of organic and inorganic anions on the Maillard reaction (MR) in glucose–glycine systems at 100 °C and pH close to neutrality was analyzed. The progress of MR markers was followed at the intermediate and final stages by spectrophotometric, pH changes, and colorimetric measurements. Two different trends were found depending on the nature of the anion. Systems with anions displaying basic properties showed an exponential correlation between the MR kinetic constants and their basicity constant values. On the other hand, systems containing anions with no acid–base properties exhibited a linear correlation between water dissolution enthalpies of their sodium salts and MR constants, indicating both a zwitterionic glycine–anion interaction catalytic effect and a relationship with their Jones–Dole viscosity constants. Finally, at a given heating time, the present anion defined the chromatic aspects of the samples, provided that the rest of the compositional variables were constant.