Kinetics of furan formation from ascorbic acid during heating under reducing and oxidizing conditions.

This study aimed to investigate the effect of oxidizing and reducing agents on the formation of furan through ascorbic acid (AA) degradation during heating at elevated temperatures (≥100 °C) under low moisture conditions. To obtain these conditions, oxidizing agent, ferric chloride (Fe), or reducing agent, cysteine (Cys), was added to reaction medium. Kinetic constants, estimated by multiresponse modeling, stated that adding Fe significantly increased furan formation rate constant, namely 369-fold higher than that of control model at 100 °C. Rate-limiting step of furan formation was found as the reversible reaction step between intermediate (Int) and diketogluconic acid (DKG). Additionally, Fe decreased activation energy of AA dehydration and furan formation steps by 28.6% and 60.9%, respectively. Results of this study are important for heated foods, fortified by ferric ions and vitamins, which targets specific consumers, e.g. infant formulations.