Role of Sugar Fragmentation in an Early Stage Browning of Amino-carbonyl Reaction of Sugar with Amino Acid

Abstract
Glycolaldehyde and methylglyoxal, both model compounds structurally related to potential C2 and C3 sugar fragments, showed extremely high reaction rates in browning with β-alanine compared to the usual reducing sugars and even to such active intermediate products of amino-carbonyl reaction as the Amadori product and osones. Production of C2 and C3 sugar fragments in a glucose-β-alanine system was negligible in acidic conditions, but increased with pH in a manner parallel to the increase in browning and also to the N/C ratio of the melanoidins. These results indicated that the proposed new pathway of browning, involving sugar fragmentation, is very important in the initial stages of browning in the Maillard reaction of neutral or alkaline solutions.