Reactive Maillard intermediates leading to coloured products-5-hydroxymethyl- and...

In the course of the Maillard reaction, labile sugar degradation products are formed that are susceptible to secondary reactions and therefore have a decisive influence on the product spectrum. Such reactive intermediates may be transformed into stable derivatives with trapping reagents, and thus be protected from further reactions. Secondary processes may also be forestalled if the primary products are removed from the reaction mixture by high-vacuum distillation. By this procedure, 5-hydroxymethyl- and 5-(1,2-dihydroxyethyl)-3(2H)-furanone have been identified directly from Maillard reaction mixtures for the first time. The activated methylene group of these 3(2H)-furanones can easily enter into condensation reactions. The coloured condensation products in turn react with primary amines to pyrrolinone derivatives, which may also contribute to the colouring observed in non-enzymatic browning.