Effects of Reaction Conditions on the Formation of α-Dicarbonyl Compounds in Maillard Reaction Model System

Abstract

The effects of reaction conditions including pH, temperature and time on the formation of α-dicarbonyl compounds(α-DCCs) from ribose/L-cysteine Maillard reaction model system were examined by separation and identification of α-DCCs by HPLC and LC-ESI-MS-MS after trapped with o-phenylenediamine(OPD). The results showed that the α-DCCs identified in the model were 1,2-pentosone, 2,3-pentosone, 3-deoxyp entosone(3-DP), 1-deoxypentosone(1-DP), N-1,4,5-trideoxy-2,3-dioxopentyl-L-cysteine, 1,4-dideoxypentosone(1,4-DDP), glyoxal(GO) and methylglyoxal(MGO). Among them the dominant were 1,2-pentosone, 1,4-DDP, 1-DP and N-1,4,5-trideoxy-2,3-dioxopentyl-L-cysteines. At pH 3.6, N-1,4,5-trideoxy-2,3-dioxopentyl-L-cysteine and GO; at pH 4.6–6.6, 1,2-pentosone, 3-DP and 1,4-DDP; and at pH 7.6, 2,3-pentosone, 1-DP and MGO were readily formed. Based on these results, a pathway of α-DCC formation at different pH was proposed. The con centration of α-DCC at 115 ℃ was higher and then was decreased when heated at a higher temperature(125 ℃) after long reaction time(60 min). The temperature and pH were the most important factors that affect the formation of α-DCCs.