The effect of pH and amino acids on the formation of methylglyoxal in a glucose-amino acid model system.

Abstract

Methylglyoxal (MGO) as a α-dicarbonyl compound not only affects food flavor and color but also contributes to the loss of nutrition and the generation of toxic compounds. The study was carried out using a glucose-amino acid model system with incubation at 120 °C to investigate the effect of amino acids and pH on the formation of MGO. MGO derivative (2-methylquinoxaline) was detected by high-performance liquid chromatography with a diode array detector. Changes in glucose, amino acids and products such as acetic acid were tested using high-performance anion exchange chromatography with an electrochemical detector or an electrical conductivity detector. Lysine and glycine had higher reactivity to form MGO and melanoidins than arginine and proline. More acetic acid was produced and a higher consumption of arginine was observed in glucose-arginine solution. Moreover, higher pH significantly accelerated the formation of MGO. Amino reactivity and pH were two important factors affecting the formation of MGO in the Maillard reaction. © 2016 Society of Chemical Industry.