Formation mechanisms Maillard reaction pathway

Its formation from rhamnose heated with piperidine acetate in ethanol, under the same conditions that produced amino-hexose-reductones from glucose and other hexoses, was described as early as 1963 by Hodge et al., who confirmed the structure by IR and NMR data and proposed a formation pathway. The formation from Amadori intermediates was been reviewed by Vernin (1981). Numerous model systems have confirmed that it is one of the main Maillard-reaction products. For instance we will mention the formation from L-rhamnose and ethylamine (Kato et al., 1972) and from pentose/glycine or alanine, whose mechanism was proposed by Blank and Fay (1996) and Blank et al. (1998), from the intermediate Amadori compound, /V-(l-deoxy-D-pentos-l-yl)glycine. Furaneol is also formed by recombination of... 

Radical reaction mechanisms during the early Maillard reaction were first detected by Namiki et al. (7, 2). He identified iV.A -dialkylpyrazine-cation radicals that originated from the primary Schiff base formed by reaction between glucose and amino acids. The glycolaldehyde alkylimine formed by a reverse aldol reaction of the Schiff base leads to a dialkylpyrazinium radical cation after self-condensation. The formation of dialkylpyrazinium radical cations, which could be detected by EPR spectrometry, represents an alternative pathway of the Maillard reaction it starts at the very beginning of die reaction, well before the formation of Amadori rearrangement products and depends on the pH value it starts around pH 7 and increases up to pH 11. 

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