A Cook's Introduction to Mushrooms
Cooking with Wild and Cultivated Mushrooms
Mushroom lovers wait patiently each year for enough rain to fall in fields and forests so they can grab their baskets and take off for their favorite hunting grounds. A new breed of mushroom admirers have learned that they can do their foraging in markets and stores which may feature wild delicacies harvested from distant parts long before local species appear. What's more, the probability of finding them on a single trip to the grocer is much greater than traveling to the woods. So for many wild-mushroom fanciers, it is no longer necessary to foray into lands festooned with poison oak and to risk a wet-footed trip through the forest.
Interest in mushrooms has increased dramatically in the last few years. Food magazines offer tempting recipes for both wild and cultivated mushrooms. Restaurant menus offer such dishes as porcini sauce over pasta, or chanterelle quiche. A well-written quarterly magazine dealing solely with fungi is now available. Its contributors are the most active and knowledgable mushroom enthusiasts in this country. It is called Mushroom: The Journal of Wild Mushrooming (see Bibliography).
The potential market is now so great that large-scale cultivation of an increasing variety of fungi provides year-round pleasure for the mushroom fancier.
The use of mushrooms as food has a long and interesting history. The Romans and the Greeks explored the culinary possibilities of fungi with enthusiasm. One mushroom was so highly prized by the Romans that certain cooking pots were set aside and reserved for its exclusive preparation. It was called a boletaria, and the genus Boletus shares this common name. Wealthy Romans hired trained collectors to be certain that the mushrooms on which they dined were edible. Animals and slaves were sometimes fed samples of fungi to test their reactions. No systematic method for identifying and naming mushrooms was adopted by the Romans. Nevertheless, we believe some of the varieties we eat today are to be found in banquet menus and recipes written during Roman times.
Today, in some European countries, trained and certified government inspectors will, for a nominal fee, separate edible from inedible fungi. Handbooks listing names, addresses, and phone numbers of such identifiers in each city are available to the public. Pharmacists in Germany display fresh mushrooms labeled with both common and scientific names.
The search for a simple test to tell if a mushroom is edible continues. The old myths of cooking with a silver coin or spoon, and the Laotian belief that harmful mushrooms make rice turn red have not been substantiated. For a few years, mycologists believed they could detect a poisonous chemical compound found in mushrooms such as in Amanita phalloides, but subsequent testing of many harmless species produced the same reaction, rendering the test meaningless.
War, poverty, and cultural customs have forced the people of many countries to survive on wild foods for certain periods of time. The Russians claim that forest mushrooms spelled the difference between life and death during their many wars when large numbers of people were forced to leave their cities. Wild mushrooms are a permanent part of the cuisine of many countries. People who collect as their forefathers did seldom become ill, because they limit their collections to a small number of well known fungi.
Wild mushrooms fruit in flushes, reach peak quality for a short time, then vanish until the following year. Frequently, too many are collected to be consumed fresh, and since they are perishable, techniques for preserving them were devised. They may be dried, pickled, frozen, or canned. Powders are made by grinding them after drying. "Ketchups" are concocted and bottled, and sometimes the mushrooms are salted down, a brining process in which salt is layered with the mushrooms.
In some European countries the number of areas where one can look for wild mushrooms is limited, but the number of foragers is not. Special days have been set aside for collecting in parks, and in some areas there are signs in three languages forbidding mushroom collecting. Research has yet to explain why the numbers of some wild mushrooms have declined in recent years. Some experts speculate that acid rain may be the cause; others feel that poor land management is responsible. The overpicking of wild mushrooms may be a factor and this is being carefully controlled in Europe. Similar concerns have been expressed in the northwestern United States and Canada that fields and forests may be altered or injured from overpicking.
In the United States, local and distant forays to favorite collecting areas are sponsored by mushroom societies. Their equipment is simple. Many people bring brown paper bags to carry edible varieties. Their baskets are as varied and individual as are their hats. Sometimes their baskets are more interesting than their contents.
Waxed paper is used to wrap uncertain mushrooms to keep them in good condition until they can be studied at home. A large knife is used to remove the entire mushroom from the ground in order to closely examine the base. It is also used to trim and remove debris. A hand lens enables collectors to look for fine details. Some bring a notebook in which to record the specific location of an area where a certain type of mushroom grows. For the artistic, it is an opportunity to record nature on paper. A field guide, especially one dealing with regional species, is essential.
We expect that those who try these recipes will be rewarded with palates sparkling from their new taste experiences. However, we must interject a note of warning to all of you adventurers who follow the culinary trail through these pages of succulent discovery, for we want you not only to be bold, but to grow old enjoying mushrooms.
Readers should be aware that toxic mushrooms may superficially resemble edible ones. We call these "look-alikes." Only by examining specimens carefully with regard to physical details can we distinguish between edible and poisonous wild mushrooms.
It is worth stressing that each single specimen must be carefully identified as well as checked for general good condition. Don't take chances.
When people consider eating wild mushrooms, they always ask these three questions:
"Are there tests to indicate which mushrooms are edible and which ones are not?" Answer: Unfortunately, there are no simple tests to determine which ones are safe to eat.
"What's the difference between a mushroom and a toadstool?" Answer: The word "toadstool" is an indefinite term referring to poisonous mushrooms. It is not commonly used by experts or knowledgeable amateurs.
"Is it edible?" Answer: Fungi are grouped for edibility as follows:
The mushrooms in which we are interested are limited to the first two groups. But we have learned to know the others so that we can delight in eating edible forms with assurance.
We want to emphasize that this book is not a field guide. Our illustrations are aesthetic rather than scientific representations of specific mushrooms. Do not use the drawings to help identify mushrooms.
Whether kneeling happily under a tree collecting golden mushrooms or standing in a produce market weighing them on a scale, positive identification of wild mushrooms for eating is essential. Each individual mushroom must be examined to be certain it is the kind you think it is.
Commercial wild-mushroom collectors sell mushrooms to retail outlets. At the present time, anyone may do this, since licenses are not required. Government agencies are in the process of developing guidelines to protect the consumer. Most retailers rely on the judgment of the person who collects the mushrooms to identify them properly. Restaurateurs are sometimes better trained. Ultimately, consumers must take some responsibility in evaluating their purchases and should shop at produce markets where they trust the produce buyer's judgment. It is exciting today to see so many wild mushrooms for sale to the general consumer.
Usually, when we decide to sample a mushroom we've never eaten before, we slice and sauté a small amount of it in butter until it is brown and soft. Then we eat it with plain crackers or toast to evaluate the intensity and the quality of its flavor. These characteristics help us decide how it might be used in a recipe. This procedure will also alert us to any allergic sensitivity we may have to any new foodstuffs. Any new food can cause unpleasant minor reactions.
Both wild and cultivated mushrooms should be carefully checked for freshness. Brown, shiny, smelly soft spots will appear if decay has begun. Look for fragmenting gills or pore surfaces, and for worm holes. The cap should be firm and have a wholesome odor.
Examine dried mushrooms sold in plastic bags with care to be sure they are not broken or showing other signs of age. They may be stored in clean dry cans or bottles, well sealed to prevent moisture or insects from entering.
Avoid the use of plastic bags for gathering or storing fresh mushrooms. Waxed or brown paper bags are preferred. Water condenses on the walls of plastic, making mushrooms moist or soggy. If they must be carried home from the store in plastic bags, remove them to a dry bowl as soon as possible. If the specimens are very moist, line and cover the bowl with a cloth or paper towel before refrigerating. Most mushrooms will last a week if treated this way.
As a rule, clean mushrooms as you use them. Wash them with as little water as possible. Especially avoid wetting the undersides of the caps. If the mushrooms are in good condition, brush or wipe them with a damp cloth. Delicate flavors are lost in soaking or boiling mushrooms.
Remove tough stems or trim the ends as needed. In some recipes, the stems are saved for later use.
Forest debris and soil can be often persuaded to leave the surface with the gentle brushing of a finger. Nylon mushroom brushes are available at cookware stores, but a soft toothbrush is just as effective.
A sharp pointed instrument such as a knife is sometimes required to clean out cracks in chanterelle caps.
In general, mushrooms should be cleaned at least half an hour before cooking so they can dry off. Mary Etta Moose, of the Washington Square Bar and Grill in San Francisco, suggests carefully tossing mushrooms in a dry skillet over heat for a short time to sear their surfaces and to help remove water.
Eating Raw Mushrooms: With a few exceptions, such as the common store mushroom, we do not recommend that mushrooms be eaten raw. Uncooked mushroom tissues are poorly broken down for digestion, depriving us of their nutritional contents. Many varieties of wild mushrooms are disagreeable when eaten raw because of viscid surfaces or peppery characteristics. However, they become readily digestible and delectable when cooked.
Using Butter and Cream: Butter seems to enhance the flavor of most mushrooms, except for some of the Asian varieties such as matsutakes and the ear mushrooms. We recommend unsalted butter in cooking. Lemon juice helps mushrooms maintain their color and adds zest to their flavor.
It is a common observation that mushrooms in some recipes seem to taste much better when cream is added. It is a culinary reality that cannot be avoided despite the current trend away from cream sauces. Milk may substituted for cream if diet is of greater importance than taste.
Adding Salt: It is recommended that salt be added to most of the recipes in this book to satisfy individual taste preferences. We are aware that many mushroom fanciers must limit salt for health reasons. Salt should be added towards the end of cooking, since it tends to remove water from mushroom tissues and makes them too soft.
Slicing Mushrooms: Slicing mushrooms allows for more rapid cooking and water loss than when mushrooms are cooked whole. Cut them into uniform thicknesses and they will cook more evenly. Mushrooms with mild and subtle flavors should be cut into large pieces so that their savory juices can be better appreciated. The best tool for cutting mushrooms is a sharp 5-1/4 inch utility knife.
For uniform slicing, because the caps have varying sizes, shapes, and textures, cut mushrooms in half so that they will lie flat on the surface of the cutting board. Soft species such as shaggy manes are difficult to cut unless the knife is sharp and the cut firm.
Precooking Mushrooms: Wild mushrooms are often precooked for several different reasons. If freezer storage is planned, it is best to sauté them in butter first, so they will have firmer texture when used later. Making duxelles is another way of preparing a mushroom in advance and utilizing otherwise discarded portions of mushrooms. To prepare marinated mushrooms, either parboil them or simmer them in the marinade liquid. Vinegar and other acidic combinations do not have the same chemical action as does heat and will not eliminate toxins. Certain helvella mushrooms should be parboiled to remove toxins and the water discarded before adding the mushrooms to other ingredients.
Using Dried Mushrooms: In using dried mushrooms, first rinse them quickly under the faucet and then place them in a bowl. Pour enough hot water over them to cover and soak for the recommended period of time for each type of mushroom. Soaking time will vary because of the different size, thickness, and shape of each variety. As a rule, this should take at least 15 to 20 minutes. Remove the mushrooms and squeeze them dry. Save the soaking liquid for use in your recipe since much mushroom flavor will have been released while rehydrating. Decant the soaking liquid slowly to avoid adding sediment that has settled to the bottom of the vessel.
Intensifying Flavor: Mushrooms exude liquid when sautéed in oil or butter. Many chefs prefer to cook most of the fluid off to develop the maximum intensity of the mushroom's flavor. Some recipes require browning the mushrooms to create more flavor. While doing this, constant vigilance is required to avoid burning.
There are four excellent reasons for preserving mushrooms:
One of the earliest methods of preserving food was to dry it. This is still an effective way to keep mushrooms for a long time without spoiling. Their taste will usually be altered in the process. Sometimes the flavor becomes more intense, and sometimes their original qualities are lost. Some varieties of mushrooms take on nuances not found when fresh. Begin by selecting mushrooms that are in good condition. They should be firm, without many worm holes, and capable of withstanding gentle handling.
When cleaning, try to prevent the mushroom from taking on water, which is what we want to get rid of. The underside of the cap is particularly prone to holding onto liquid. Clean the top of the cap with a brush, a damp cloth, or your finger. Trim the stems.
Cut flat, even, broad slices about 3/8 inch thick. The slices should be of uniform width so that they will dry at the same speed. Plan to work on your mushrooms as soon as you bring them home. Do not leave them lying around to deteriorate. Avoid overlapping the slices on trays so that they will dry evenly.
Many mushroom fanciers have developed unique drying techniques. Some hang flats of wire screen doors, plastic mesh, etc., overhead with wire or cord, especially above ovens, fireplaces, or heating units. One creative person has converted an abandoned refrigerator into an efficient dryer using a fan and a 75-watt light bulb. Many effective and inexpensive commercial dehydrators are available.
When slices are bone dry, no less, place in metal cans or glass jars. If you are uncertain about their state of dryness, transfer them into paper bags, and hang in a dry, warm place over an oven or fireplace for a few days. Then put them into containers, adding a few dried bay leaves or a handful of whole black peppers to discourage insect pests. Be sure to label containers with the date and the species identification.
Freezing is a fine technique for putting mushrooms away for a future day when none are growing. They can be frozen fresh or precooked. Some small caps may be frozen whole, after examining, cleaning, and completely draining them. Allow 20 to 30 minutes for draining. Larger specimens should be sliced or cubed into 1/4-inch pieces. Heavy plastic is acceptable for freezing, or use freezing containers. Matsutakes and the boletes are preserved beautifully this way, retaining their aromas and spiciness as well as their textures.
There are two methods of precooking mushrooms for freezing. One way is simply to freeze a dish made with mushrooms, such as a quiche, ready to heat and serve. The other is to sauté the mushrooms in butter or oil, or both, for 5 minutes before transferring them to a freezer container. Be sure to include the liquid remaining in your saucepan. Such food will keep well for 6 months.
It's easy to develop a mutual admiration relationship with mushrooms. You stuff them, then let them stuff you. Common store mushrooms are perfect receptacles for a variety of foodstuffs such as onions, tomatoes, greens, meat, or chopped mushroom stems enhanced with butter, herbs, or spices.
The simplest mode of preparation is to remove the stem from the cap or use hollow-capped species such as morels. Stuff them, and bake. They don't last long as party food, and they will contribute complements and compliments for your main course at dinner.
Use medium- to large-sized caps: medium for hors d'oeuvres and appetizers, large ones for main dishes. Select very firm mushrooms with broad stems and unopened caps that will hold more stuffing.
Clean the tops and stems with a soft brush and a little water. Drain for 15 to 30 minutes in a colander. Remove any debris from the stems, and freshen up the cut end of the stem by trimming.
Gently twist off the stems of gilled mushrooms. You may need to use the end of a knife to encourage the stem to leave. Remove the cottony veil from common store mushrooms and their relatives. Don't fail to incorporate these fragments and the stems in the stuffing.
Prepare the caps by brushing them with soft or melted butter. This will sear the surface of the mushroom when heated and will help it hold its shape. Another way of firming them up is to brush them with butter and broil them cavity-side down under a preheated broiler for 5 minutes before being filled.
Stuffing material should be partially or completely precooked and ready for placement as soon as the caps have been prepared. Spoon the stuffing into the hollowed portion of the caps, press the material down tightly, and move the caps onto your baking surface. Mushrooms release a good deal of liquid when heated, so it is best to use a shallow baking pan or a jelly roll pan, which has raised edges, to retain the juices. It is advisable to fill them before placing them on the baking pan, since you want your mushrooms to have a neat appearance. And the pan will be much easier to clean.
Baking or broiling time will vary according to the size of the cap and the nature of the filling. It is best to start with a preheated oven. Keep your eye on your achievements, allowing them to brown without burning. Serve them immediately.
Mushroom varieties other than the common store ones may be stuffed, such as:
Boletus edulis (cèpes or porcini): Large caps may be prepared as small pizzas. Serve stuffed boletes alongside your meat or fish dish; they may be filled with a wide variety of foods appropriate to the entree. The superb full flavor of this mushroom's juice blends with any stuffing to make it unique and rich.
Agaricus augustus (the prince): One of the best mushrooms for stuffing because it is usually large and the cap forms a deep bowl. The strong, sweet almond flavor exuding from the prince adds an exotic quality to whatever ingredients you select to stuff it with, such as sautéed chopped stems cooked with minced garlic, bread crumbs, fresh tomatoes, and soy sauce. The special princely flavor filters through all the ingredients.
Morels: These were designed by nature for stuffing. Fill their hollow interiors with mixtures of ground beef, bacon, lamb, crab, or simply browned onions, bread crumbs, and parsley. Any stuffing will feature the morel's fabulous aftertaste.
Shiitakes: This is the finest of the cultivated mushrooms. Asian recipes frequently recommend steaming them when they are filled. Dry shiitakes should be reconstituted for 20 minutes in hot water before using.
Matsutakes: Expensive to buy and rare to find, a large stuffed matsutake could be the vegetable for a large dinner party. You might want to marinate it with soy sauce and dry sherry for 20 minutes. Remove the stem and use it chopped with pork or chicken, moistened with the marinade. Brush the cap with peanut oil. Fill and grill or bake in a hot oven until brown. Small matsutakes can be stuffed by making a cut in the cap and spreading the opening enough to place stuffing inside. They are very attractive served with steamed vegetables.
You will find suggestions for other stuffing mixtures in the sections on specific mushrooms.