I was recently at one of my favourite hamburger restaurants, Big Smoke Burger in Toronto, and reminded of the mushroom’s humble status as, what many would say, an under-appreciated side attraction. In this example, a scant few made their requisite appearance as a topping on a burger.
In North American cuisine, mushrooms rarely take centre stage but rather take on the role of sidekick with many foods we view as vices; pizza, bacon cheeseburgers, fired in butter for steak or they get hidden in the background of foods like cream of mushroom soup, omelets, or spaghetti sauce.
The mushroom of choice in these examples tends to be the white button variety, not a heavy hitter in terms of nutrition or antioxidant power compared to other varieties, but more on that later.
Is it simply an issue of poor PR?
With the exception of the portabella mushroom, which is commonly used to replace beef or other meats, in vegetarian burgers, rare is it to find mushrooms as a main ingredient in a meal or as an entrée. Why is that? I am not entirely sure. Perhaps it’s because mushrooms were never held in high regard, save the truffle, like meat was in lean times, which was seen as a luxury item. As peoples’ standards of living improved, people most likely focused on those foods that were once a rarity.
Of note, mushrooms grow from microscopic spores, and all plants that grow from spores are called fungi. Because mushrooms have no chlorophyll and are unable to synthesis their own nutrients, they get all their nutrients from organic matter: in the wild, they grow on other plants such as trees, both living and dead, on dead leaves etc.
Cultivated mushrooms tend to be grown on compost derived from materials such as straw, corn cobs, cotton seed and corn husks, and nitrogen supplements.
Time to get the respect they deserve
Moving these under-appreciated fungi to the culinary centre stage is not only easy, but tasty. Mushrooms come in a variety of types, each with their own unique qualities. What people struggle with, is not knowing how to make them the focus of an entrée.
By far the most popular mushroom is the white button, in fact they represent the vast majority of mushrooms consumed in North America – we see them everywhere; fried and used as a burger topping, on pizza, steak, in prepared spaghetti sauces and even canned. They are the mildest tasting and blend well with almost anything.
Less popular are the so-called specialty mushrooms which are more expensive but arguably of better quality in terms of flavour. In this category, you’ll find crimini which are a smaller relative to portabellas and have a light tan to rich brown cap. They have a deeper, earthier flavour than the white button.
Portabella can measure up to 15cm in diameter and have a deep, meat-like texture and flavour, making them the obvious choice for vegetarian burgers. The enoki are very tiny with button shaped caps and long spindly stems with a mild taste and crunchy texture.
Oyster can be gray, pale yellow or even blue, with a velvety texture and delicate taste. My personal favourite are shiitake. They have a tan to dark brown and umbrella-shaped cap. They have an exceptionally rich and woodsy flavour when cooked. There is no shortage of recipes to be found on the internet – pick a few and start enjoying the magic of mushrooms.
More than meets the eye – fungus nutrition
Not only are mushrooms versatile and good tasting, many may be surprised to learn that these seemingly unassuming plants pack some of the most powerful health benefits. They give a lot of bang for their nutritional buck. For very few calories (about 25 calories per 100 g of mushrooms on average) they are a excellent source of key nutrients such as potassium, B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), selenium, copper, zinc and they’re sodium free.
One cup (250 ml) of sliced cooked portabella mushrooms has more potassium than a medium banana! Potassium is a mineral which helps to maintain a healthy fluid balance in the body and also is important in nerve transmission, involved in muscle contraction including regulating heart function, helps to convert glucose (blood sugar) into glycogen (fuel for muscles) and helps to reduce blood pressure.
The under-appreciated nuances of plant nutrition
The other health promoting properties of mushrooms, like all plant foods, are found in the non-traditional vitamin and mineral route: phytochemicals & antioxidants. Mushrooms are packed a unique antioxidant called l-ergothioneine. Mushrooms contain higher concentrations l-ergothioneine than either of the two dietary sources previously believed to contain the most: chicken liver and wheat germ. Studies have shown that shiitake, oyster, king oyster and maitake mushrooms contain the highest amounts of l-ergothioneine, with up to 13 mg in a 3-ounce/86 g serving. This equals forty times as much as is found in wheat germ.
Antioxidants help to protect body cells and tissues against damage, much like a shield protects a warrior from the onslaught of an enemy’s arrow. This particular antioxidant is heat stable and therefore present in both raw and uncooked mushrooms.
A functional food at its best
Mushrooms also have a form of carbohydrate called beta-glucan which emerging research has shown to have a positive effect on the immune system, specifically enhancing the activity of natural killer cells. Beta-glucan seems to help reduce the risk of hormone dependent cancers such as prostate and breast. And like most plant based foods, mushrooms have anti-inflammatory properties which may help to positively modulate the immune system.
When selecting, storing and cleaning mushrooms, remember the following;
How to Select:
- Purchase mushrooms that are firm with a fresh, smooth appearance.
- Surfaces should be dry, but not dried out, and appear plump.
- A closed veil under the cap indicates a delicate flavor, while an open veil and exposed gills mean a richer flavor.
How to Store:
- Mushrooms keep for up to a week in the refrigerator.
- Keep mushrooms in original packaging until ready to use.
- Once opened, store mushrooms in a porous paper bag for a prolonged shelf-life.
- Avoid storing in airtight containers – they cause condensation, which quickens spoilage.
- Fresh mushrooms should never be frozen, but frozen sauteed mushrooms will keep for up to one month.
How to Clean:
- Brush off any dirt with a damp paper towel or fingers.
- Rinse fresh mushrooms only briefly under running water and pat dry with a paper towel. Never soak them, as they absorb moisture.
- Trim the end of the stem before using.