Mushrooms: Do They Have A Distinct Aroma?

Mushrooms are known to have distinct odours, which can be used to identify them. While most mushrooms are barely scented, some varieties have strong odours, such as the Stinky Horn Mushroom (Phallus Impudicus), which has a strong and foul odour. Mushrooms can also have pleasant odours, such as the coconut scent of Lactarius hibbardae or the cucumber or watermelon rind scent of Clitopilus prunulus. The odour of mushrooms can be affected by various factors, such as the location on the mushroom, with some parts having a stronger scent than others, and the method of containment, as certain mushrooms may develop a distinct odour when enclosed in waxed paper or another container. Additionally, the freshness of mushrooms plays a crucial role in their scent, with spoiled mushrooms emitting a strong or sour odour.

Mushrooms with a distinct odour

Mushrooms are typically fragrance-free, with only a faint smell of earth and dirt, which is safe for consumption. However, some mushrooms have a distinct odour. For instance, the mushroom Pholiota squarrosoides, which grows in large clusters, has an odour that is somewhere between coffee and chocolate, yet the flesh of the mushroom lacks this scent. Other species of Pholiota give off a green corn smell. Some mycologists have pointed out that certain species of Cortinarius and Hebeloma mushrooms have a honey-like scent that is only detectable at the base of the stipe and not on other parts of the mushroom.

Clitopilus prunulus, a type of sweetbread mushroom, has a farinaceous odour, which is similar to fresh meal or raw pastry, though some liken it to cucumber or watermelon rind. Tricholoma dulciolens, a member of the matsutake mushroom group, has a strong and memorable scent that can fill a small room. Some have described it as reminiscent of Russian olive flowers.

Cortinarius camphoratus has an unpleasant odour of rotten potatoes, while Cortinarius violaceus and C. hyrcinicus have a notable scent of cedarwood. The crushed caps of Gymnopus perforans, a species commonly found on needle beds of spruce and fir, have a strong and unpleasant odour of rotting cabbage. Other species of Gymnopus may smell pleasantly sweet or distinctly like garlic or onion. Hydnellum suaveolens, a tooth fungus, has an odour described as similar to anise, peppermint, or bath soap.

One mushroom with a particularly strong odour is the stink horn mushroom, or Phallus impudicus. This mushroom, which resembles a male genital, has a strong and distinct smell. It is considered noxious due to its foul odour, although it is not considered poisonous.

Mushrooms that smell bad

Mushrooms have a wide variety of odours, with some having particularly unpleasant aromas. Most mushrooms are barely scented, so a strong smell can be a telltale sign that your mushrooms have gone bad. Here are some examples of mushrooms that are known to smell bad:

Cortinarius camphoratus

Cortinarius camphoratus has an unpleasant odour of rotten potatoes. This mushroom can often be smelled before it is even found. It is visually similar to C. traganus, but the odour easily distinguishes the two species.

Tricholoma sulphureum

Commonly known as The Stinker or Sulfur Knight, Tricholoma sulphureum exudes an aroma similar to coal gas. It is considered poisonous and is far too smelly to eat.

Russula fragrantissima

Russula fragrantissima, or The Fragrant Russula, starts out with a pleasant aroma of almonds or maraschino cherries, but later in its life cycle, it takes on a very foul odour. It is considered inedible.

Gymnopus perforans

This species of mushroom has a strong and rather unpleasant odour of rotting cabbage. It is commonly found on the needle beds of spruce and fir trees.

Pholiota squarrosoides

While the mushroom itself does not have a bad smell, the large clusters in which it grows have an odour somewhere between coffee and chocolate.

Signs of Bad Mushrooms

In addition to a bad smell, there are several other signs that indicate mushrooms have gone bad. These include a sticky and slimy texture, dryness, wrinkling or shrivelling, discolouration, dark spots, and the presence of fuzzy mould. Fresh mushrooms should have a slightly sweet and earthy scent, so an overly sour or pungent smell can indicate spoilage.

Stinkhorn mushrooms

Many mushrooms have distinctive odours, and stinkhorn mushrooms are known for their foul-smelling, sticky spore masses. They are often found in mulch, lawns, and areas with bare soil, and their sudden appearance can be a shock to gardeners. Stinkhorns get their name from their unpleasant odour, which has been described as resembling rotting flesh or dung. This smell attracts insects, particularly flies, which then help to disperse the spores to new locations.

Mushrooms that are safe to eat

Mushrooms have a wide variety of smells, and their scent can be a good indicator of their freshness. Most mushrooms are barely scented, so a strong, foul odour can be a telltale sign that they have gone bad. Some mushrooms have a distinctive odour, such as the Pholiota squarrosoides, which smells like a mix of coffee and chocolate, while others have a farinaceous odour, reminiscent of cucumber or watermelon rind.

When it comes to foraging for mushrooms in the wild, it is important to remember that not all mushrooms are safe to eat. Some unsafe mushrooms may look similar to edible varieties, so it is crucial to be able to identify mushrooms correctly before consuming them. Ingesting certain species can be harmful or even fatal.

• Choose mushrooms with tan or brown gills, as mushrooms with white gills can often be poisonous. The most deadly mushroom family, Amanitas, typically have white gills.
• Select mushrooms with white, tan, or brown caps and stems, and avoid those with red caps or stems, as they are generally unsafe to eat.
• Avoid mushrooms with scales on the cap or a ring of tissue beneath the cap, as these could be signs of poisonous mushrooms.
• Look for distinctive-looking mushrooms, such as the Cauliflower mushroom, which can grow very large and is great for cooking, although it can be tricky to clean.
• Field blewits, with their smooth, grey-beige cap and blue/violet fibrous skin over the stem, are another edible variety often used by chefs. They often grow in rings or groups.
• Dryad's Saddle, the largest capped mushroom in the UK, can be found on dead elder trees. It has ochre to dark yellow caps with brown scales and is best eaten when young as it has a watermelon taste.
• Chicken of the Woods, a fleshy bracket fungus with a bright, creamy yellow colour and bands of orange, is commonly found on oak and cherry trees. However, some people may experience stomach issues after consuming it.

Remember, it is always better to be safe than sorry. If you are unsure about a mushroom's edibility, it is best to consult a professional mycologist or seek advice from foraging communities and online forums.

How to store mushrooms

Mushrooms are best cooked and consumed when fresh. While they can be frozen, this will result in a loss of nutritional value and texture. If you do choose to freeze them, make sure to wipe them down with a paper towel first and store them in an airtight bag. Do not wash the mushrooms before freezing.

When it comes to storing fresh mushrooms, moisture is the number-one enemy. Therefore, it is best to avoid storing them in plastic containers or bags, as plastic traps moisture, leading to discoloration, mould, and slime. Instead, place the mushrooms in a paper bag and keep them in the fridge. You can also wrap them in paper towels and then place them in an open plastic bag in the fridge.

If you are storing presliced mushrooms, their shelf life may only be 5 to 7 days when stored correctly. Some delicate varieties, like maitake or oyster, may only last for a few days. Therefore, it is important to keep an eye on them and check for signs of spoilage. Mushrooms that have gone bad will typically have a sticky and slimy texture, or they may appear dry and shrivelled. They should also be discarded if they have noticeable discolouration, dark spots, or fuzzy mould. Most mushrooms have little to no scent, so a foul odour can be another indication that they have spoiled.

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