Effects of reaction parameters on the formation of α-Dicarbonyl compounds in Glucose-Glycine Maillard chemical model system

Derivatization with o-phenylenediamine(OPD) as well as qualitative and quantitative analysis with HPLC were employed to investigate the effects of reaction conditions(temperature,p H,duration and reactant ratio) on the formation of three α-dicarbonyl compounds including 3-deoxyglucosone(3-DG),glyoxal(GO)and methylglyoxal(MGO) in glucose-glycine maillard chemical model systems. The results showed thatthe increasing of temperature promoted the generation of MGO and GO within 80~140 ℃,while the level of 3-DG increased to the highest at 110 ℃,and decreased subsequently. The effects of p H value within 5 ~9 were similar to that of the temperature:the formation of GO and MGO increased with the increasing of p H values,while the levels of 3-DG increased to the maximum as p H vaue of 6. The rate of 3-DG and GO formation decreased as the extension of duration,but it tended to be constant for MGO within 2 h. In terms of the substrate ratio,the formation of 3-DG could be enhanced by the increasing of relative content of glucose,while increasing of glycine levels could promote GO and MGO formation. The results may provide experimental basis to certain extent for flavor compounds with α-dicarbonyl compounds as intermediate products.