Amadori rearrangement
Japanese: アマドリ転位
A molecular rearrangement in the early stage of the Maillard reaction. A Schiff base converts to a more stable Amadori compound.
The Amadori rearrangement is a molecular rearrangement occurring in the earliest stage of the Maillard reaction. Amino acids and reducing sugars condense to form a Schiff base, which rearranges to a more stable Amadori compound (ketoamine). Reported by Mario Amadori in 1925.
Amadori compounds are relatively stable, but further reaction produces α-dicarbonyl compounds, leading to Strecker degradation and melanoidin formation. The Amadori rearrangement is the prologue to the Maillard reaction's 'story of color and aroma.'
In early miso aging, Amadori compounds accumulate and gradually proceed to subsequent reactions, progressively darkening color and complexifying aroma. This stepwise progression is one of the chemical realities behind 'aging.'