On Food and Cooking

Other mushrooms offer a wide range of
aromas. A close relative of the common
mushroom produces the essence of almond
extract, while more exotic species are valued
for such flavor notes as cinnamon, pepper,
garlic, pine needles, butterscotch, and
shellfish. Shiitake mushrooms owe their
distinctive aroma to an unusual molecule
called lenthionine, a ring of carbon and sulfur
atoms, which is created by enzymes when the
tissue is damaged. Lenthionine production is
maximized by the common practice of drying
and then rehydrating shiitakes in warm water
(it’s minimized by rapid cooking of the fresh
or dried mushroom, which destroys enzymes
before they have a chance to act). With a few
exceptions (chanterelles, oysters, matsutakes),
drying intensifies mushroom flavor by a
combination of heightened enzyme activities
and browning reactions between amino acids
and sugars. Shiitakes and boletes, or porcini,
are familiar examples, and especially