usually thought of as a particularly good source of nutrients, mushrooms
actually rank rather high in nutritive value. They contain a substantial
amount of B vitamins, selenium, copper, and some other trace minerals,
and are very low in calories. Moreover, researchers have discovered
they contain antibacterial and other medicinal substances, including
anti-tumor compounds called triterpenoids.
mushroom's distinctiveness derives, in part, from the fact that it is
not truly a vegetable but a fungus, a plant that has no roots or leaves,
no flowers or seeds, and that does not require light to grow (although
some do need light to fruit). Instead, it proliferates in the dark and
reproduces by releasing billions of spores. There are about 38,000 varieties
of mushrooms, from deliciously edible to highly toxic. Most varieties
grow wild; in fact, their earthy flavour has been appreciated for thousands
of years. The Egyptian pharaohs decreed mushrooms to be a royal food.
some mushrooms still refuse to be "domesticated," many can
be cultivated in caves or cellars, or grown year round in specially
designed structures in which all aspects of the environment, light,
temperature, humidity, and ventilation can be controlled. As a result,
many varieties of mushrooms are affordable and widely available, no
longer exclusively reserved for royalty.
To minimize waste in recipes that call
for caps only, choose mushrooms with short stems. Alternatively, reserve
the stems for another recipe.
For garnishing, or for cooking whole
in a stew or braise, choose small mushrooms; for general cooking purposes,
select medium-sized ones. For stuffing, look for mushrooms with caps
large enough to hold a generous amount of filling.
When shopping for specialty mushrooms,
there is no single rule of thumb for judging freshness since they are
all quite different and will not have the clean, uniform appearance
of cultivated button mushrooms, particularly if gathered in the wild.
They should, however, be firm and meaty, as well as dry to the touch
but not withered. Even uncooked, they should have an appealing earthy
It is important to conserve just the right amount of moisture when storing
mushrooms. If left completely uncovered, they will dry out; if enclosed
in moisture-proof wrapping, they will become soggy and begin to decay.
A good compromise is to place mushrooms purchased in bulk in a loosely
closed paper bag or in a shallow glass dish covered with a kitchen towel
or a lightly moistened paper towel. Leave prepackaged mushrooms in their
unopened package. Don't wash or trim mushrooms before storing them.
mushrooms on the refrigerator shelf, not in the refrigerator salad drawer
, which tends to be humid, for no more than a few days. Unopened, prepackaged
mushrooms will stay for up to a week. If mushrooms begin to darken (and
their caps open) with age, they can still be used for cooking and flavouring
Dried mushrooms will keep almost indefinitely
if wrapped in plastic or placed in a tightly closed jar and stored in
the refrigerator or freezer. They can also be stored in a cool, dark
place for up to six months.
Since mushrooms are very absorbent, try to minimise their contact with
water when cleaning them. Simply wipe them with a dry paper towel or
a damp sponge or cloth, or use a soft brush (you'll find special mushroom
brushes at cookware shops, or you can use a small soft-bristled paintbrush).
If the mushrooms have a lot of soil adhering to their stems, just trim
off the stem bottoms. If absolutely necessary, place the mushrooms in
a colander and rinse them quickly under cold running water; do not soak
them or they will absorb too much water.
mushrooms stems are edible. All you need to do is trim off the very
ends where the stem might be too spongy (try cutting through the stem
with a small knife; if it feels spongy, trim off that section). If the
recipe does not call for stems, break them off at the cap and save them
(chopped, wrapped, and frozen) for later use in a stock or soup. However,
shiitake stems are usually too fibrous to be edible and should be cut
off before preparing the caps. (Use the stems to flavour stock.).