Generation of proline-specific Maillard compounds by the reaction of 2-deoxyglucose with proline

The proline-specific Maillard products including 2,3-dihydro-1H-pyrrolizines, hexahydro-7H-cyclopenta[b]pyridin-7-ones, and cyclopent[b]azepin-8(1H)-ones were generated by both 2-deoxyglucose/ proline and glucose/proline model reactions at 180 degrees C for 2 h. The amounts of these products generated in 2-deoxyglucose/proline reaction were far less than (< 12%) those generated in the glucose/proline model reaction at both pH 9.0 and 4.0. The pH effect on the formation of these products in the 2-deoxyglucose/proline model was not significant, while a lower pH favored the generation of these products in the glucose/proline reaction. The generation of the active precursors of these proline-specific Maillard products from 2-deoxyglucose is proposed.