Solid-phase Maillard Reaction between L-glutamic Acid and Glucose as Determined by TG-SPME-GC-MS

In order to explore Maillard reaction without aqueous solution,a novel combinatorial system of thermogravimetrysolid phase microextration-gas chromatography-mass spectrometry(TG-SPME-GC-MS) was designed and a glutamic acidglucose solid phase Maillard reaction pattern was established.Based on sampling in different temperature ranges,the pyrolysis behavior of pure glucose and mixtures of glutamic acid and glucose at different ratios(1:1,1:2,1:4,1:6,1:8,or 1:10) were investigated and the release tendency of pyrolysis products in different pyrolysis stages was also discussed.The mixture of glutamic acid and glucose exhibited a lower initial pyrolysis temperature(130 ℃) than that of pure glucose(185 ℃).At the initial reaction stage(130-170 ℃) of solid-phase Maillard reaction,the released product was the pyrolysis product of pure glucose.Maillaid products were generated from 170 ℃,which included 2-pyrrolidone,L-pyroglutamic acid methyl ester,2-(2oxopyrrolidino) acetamide,and 5-methyl-1H-pyrrole-2-carbaldehyde.