Kinetics of conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part IV - Formation of HMF

•Kinetics of HMF formation in mānuka honey was studied.•Reaction was first-order during induction and subsequently zero-order.•Rate was correlated to total and free acidity, amino acids and phenolic acids.•A simulation of HMF formation in mānuka honey was created.

During a study of the conversion of dihydroxyacetone (DHA) to methylglyoxal (MGO) in maturing New Zealand mānuka honey, the kinetics of formation of 5-(hydroxymethyl)furfural (HMF) was studied at temperatures from 4 to 37 °C. Formation of HMF was first-order during an induction period and zero-order thereafter indicating that the mechanism includes the formation of certain critical intermediates and that these require time to build up; the duration of the induction period depended primarily upon temperature.The zero-order rate constant at 37 °C was the same for mānuka honey and clover honey doped with 2000 or 10,000 mg/kg DHA and for artificial honey with 2000 mg/kg of DHA and either alanine or proline and alanine added. Zero-order rate constants for artificial honey with added amino acids were less than for a control without amino acids.A simulation was created to predict the formation of HMF over time at 37 °C in mānuka honey.