On Food and Cooking

Even more fortunate and complex are the
reactions responsible for the cooked color and
flavor of bread crusts, chocolate, coffee beans,
dark beers, and roasted meats, all foods that
are not primarily sugar. These are known as
the Maillard reactions, after Louis Camille
Maillard, a French physician, who discovered
and described them around 1910. The
sequence begins with the reaction of a
carbohydrate molecule (a free sugar or one
bound up in starch; glucose and fructose are
more reactive than table sugar) and an amino
acid (free or part of a protein chain). An
unstable intermediate structure is formed, and
this then undergoes further changes,
producing hundreds of different by-products.
Again, a brown coloration and full, intense
flavor result. Maillard flavors are more
complex and meaty than caramelized flavors,
because the involvement of the amino acids
adds nitrogen and sulfur atoms to the mix of
carbon, hydrogen, and oxygen, and produces