Button mushrooms are the common, familiar white mushrooms that are used in a wide range of recipes and cooking techniques, from tarts and omelets to pasta, risotto, and pizza. They're the workhorse of the mushroom family, and their mild flavor and meaty texture make them extremely versatile.
What Are Button Mushrooms?
Button mushrooms are the immature form of the edible fungus Agaricus bisporus, which also includes cremini mushrooms and portobello mushrooms. In fact, all of these mushrooms are the same mushroom at different stages of maturity. Button mushrooms are the least mature, have a pale white color, and measure 1 to 3 inches across. The next phase of development brings us cremini mushrooms, which are the in-between stage, small and slightly brown in color, and then finally portobello mushrooms, which are the largest, darkest brown, and most mature stage of the species.
Button mushrooms, also called white mushrooms or white button mushrooms, are the most popular mushroom variety, making up 90 percent of the mushrooms consumed in the United States. They're also the least expensive, and have the mildest flavor, though they readily absorb the flavors that they're cooked with. They can be eaten raw, and cooked via sautéeing, stir-frying, grilling, braising, and roasting.
How to Cook With Button Mushrooms
Button mushrooms have a relatively high water content relative to their more mature counterparts. This means that cooking them takes a little bit longer than cooking cremini or portobellos. Undercooked button mushrooms can have a slightly squishy consistency, but cooking them longer will cook away their water content, giving them a more dense, almost meaty texture.
Since they grow in the ground, button mushrooms can sometimes have particles of dirt on them. In recent decades it was commonplace to brush the dirt off without wetting the mushrooms because it was feared that rinsing them would cause them to absorb water like sponges. But button mushrooms are already saturated with water—their water content is around 92 percent. If you soaked them for a period of time, they might absorb a bit more water, but rinsing away the dirt won't have any appreciable effect on their moisture content.
Likewise, some chefs, especially those with old-school fine-dining training, recommend peeling mushrooms before cooking. This is done using a paring knife, reaching under the cap of the mushroom with the edge of the knife and pulling the skin toward the top of the cap. This was done to make the mushroom look nice, as a way of removing dirt, and also because the skins on older mushrooms can sometimes be tough. But with button mushrooms, toughness isn't an issue, and rinsing is an easier and equally effective method of removing dirt. So peeling is definitely optional.
Button mushrooms are easy to slice and don't require much pressure from the chef's knife. Their flesh is somewhat delicate, and they should be handled gently. They bruise easily, and when that happens, the white flesh turns first pink and then brown.
Button mushrooms are great in pasta dishes, stir-frys, omelets, salads, soups, sauces, as a topping for pizzas and burgers, and as a side dish, served sautéed with butter, herbs, and garlic, especially alongside grilled steaks and other meats.
What Do They Taste Like?
Button mushrooms taste alternately earthy, meaty, and brothy, a combination of flavors known as umami, though their flavor is comparatively mild. This umami flavor comes from a type of amino acid called glutamate, which is naturally present in mushrooms, as well as in other foods, such as parmesan cheese and anchovies. With button mushrooms, the umami flavor is less powerful, because their relatively high water content effectively dilutes it. But, as mushrooms mature into their cremini and portobello phases, their water content diminishes, and the umami flavor is enhanced.
Button Mushroom Recipes
Here are a few easy recipes you can prepare using button mushrooms.
Where to Buy Button Mushrooms
Button mushrooms are widely available at supermarkets, grocery stores, and farmers' markets. At the grocery store, look for loose mushrooms in the produce department, and select ones that are smooth, plump, and firm. A closed veil, meaning the part underneath the cap, indicates a fresher mushroom, while an open veil, which exposes the dark gills underneath, means it is less fresh, although these mushrooms may have a richer flavor. Avoid mushrooms that appear dried or shriveled.
Button mushrooms are also available in plastic-wrapped containers, which are less than ideal since you can't inspect them individually. And, you can also buy them sliced, although these have a shorter shelf life. You can also try growing button mushrooms using a mushroom growing kit.
Storage
Because button mushrooms contain so much water, they are prone to turning moldy or slimy. The best way to avoid this is to use them as soon as possible. But storing them in the fridge for two to three days is fine provided they aren't encased in plastic, which traps in moisture, which in turn can cause them to turn slimy. Avoid storing whole mushrooms in plastic bags.
To preserve freshness, buy whole mushrooms and store them loose in the crisper drawer on the humid setting, with a clean paper towel underneath them. If you buy the sliced kind that is sold in a container with a plastic wrapper over them, remove the plastic wrap and store them in their container, uncovered, in the crisper drawer.