TheMaillard reaction is oneof four primary non-enzymatic browning reactions.
This reaction requires thepresenceof anamino-bearing compound, a reducing
sugar, andwater. Basic aminoacids, suchas lysine, areespecially susceptible.
When the reducing sugar is ahexose, 5-hydroxymethyl-2-furaldehyde, or HMF,
is oneof the intermediate reactionproducts, especially at lower pH. The
structureof HMF is shown below, anda simplifiedMaillard reaction scheme is
shown inFigure1.
2
The formulaweight of HMF is 126.1, and theUV
max
is
283nm. On further reaction, anumber of highmolecular weight polymeric
materials are formed, resulting in color and flavor changes. These changesmay
ormay not be desirable; someof thenegativeeffects includeoff-flavors or off-
colors, and thepotential loss of essential aminoacids suchas lysine.
TheMaillardReaction
OH
O
O
