Determining Odor and Taste
by Michael Kuo
The odor and taste of a mushroom can be important in the identification process. I'm aware that you probably don't need me to tell you how to use your sniffer and your taste buds--but there are a few things you may want to keep in mind when it comes to smelling and tasting mushrooms.
I take a piece of the mushroom (or a whole cap, in the case of small mushrooms) and crush it between my finger and thumb before trying to assess an odor. Usually the cap is the best part of the mushroom to test, but occasionally you will discover that some other part of the mushroom should be tested (for example, the stem bases in Agaricus).
Some people cannot detect certain odors; I can't smell the "phenolic" odor in Agaricus species, but I can sniff out "farinaceous" from yards away. Experience will tell you which odors you are best at detecting.
"Not distinctive" is probably the most common mushroom odor, but distinctive smells include:
- Farinaceous or mealy. Often compared to the odor of cucumbers, watermelon rind, or an old grain mill. Common in many mushrooms, including Polyporus squamosus, Agrocybe praecox, Mycena galericulata, Tricholoma sejunctum, Clitopilus prunulus, and Entoloma abortivum. Some mycologists (Smith et al., 1979; Moser, 1983), armed with better sniffers than mine, subdivide "farinaceous" into three odor groups: strictly farinaceous, cucumber/farinaceous, and rancid-oily-fishy/farinaceous. Believe it or not, the cucumber/farinaceous sub-odor has been upheld by chemical research (Wood et al., 1994) as a valid distinction, and the chemical trans-2-Nonenal has been identified as being responsible for it.
- Foetid-Russula odor. Often compared to benzaldehyde (whatever that is); to me it smells like maraschino cherries that have gone slightly bad. See the Key to Foetid Russulas.
- Fishy or shrimplike. Examples include Lactarius volemus and Russula xerampelina.
- Spermatic. Primarily in species of Inocybe. (See also "Hey, That Mushroom Smells Like...")
- Like anise (the flavoring in ouzo or black licorice). Examples include Clitocybe odora and Agaricus.
- Like green corn. Examples include species of Inocybe and an odd species of Porpoloma I have not yet identified.
- Like bleach. Primarily in species of Mycena.
- Like swamp gas or coal tar. Primarily in species of Tricholoma.
- Like apricots. Primarily in species of Cantharellus.
- Like almonds. Primarily in species of Agaricus.
- Like garlic. Primarily in species of Marasmius.
- Phenolic. I wish I could help you with a comparison, but I don't sense this odor well. When others say a mushroom smells phenolic, I smell nothing or, in some instances, an almond odor that has been pushed to the extreme. Primarily in species of Agaricus.
- Foul. Any mushroom can smell foul after it has begun to decay, but some have a strongly unpleasant odor anyway. Examples include Stinkhorns and Lepiota cristata.
Since there are some deadly poisonous mushrooms out there, you should be careful when it comes to tasting mushrooms. One swallowed bite of Amanita bisporigera or Galerina marginata could contain enough poison to kill you. To be honest, it is doubtful that swallowing your spit after you have tasted and spit out a piece of deadly mushroom is likely to cause you any harm (sorry to be graphic, but I want to be as clear as possible). Still, it is better to be conservative in matters like this; please study and follow the guidelines below, and bear in mind that taste is only one of many features that can help you identify a mushroom.
- Study the Amanitas, especially the deadly ones. Memorize their details--from button stage to maturity--and never taste any mushroom that could remotely be similar.
- Do not taste any mushroom unless you are reasonably sure you have approximated its identity and that it belongs to a genus that holds no species known to be deadly poisonous. For example, you know you are holding a bolete, and you wonder whether it might be a Tylopilus; a reasonable scenario. But never pull one of these: "What's this? I have no idea. I think I'll taste it."
- If your mushroom has a mealy or bleachlike odor, do not waste your time (or your taste buds) testing its taste. It will undoubtedly taste more or less like it smells--and assessing the odor is already enough for identification purposes.
- To determine taste, tear off a very small piece of the mushroom's cap (including flesh as well as gills or pores). Put it on the tip of your tongue, and hold it in your mouth for a few seconds (perhaps a little longer in the case of Lactarius mushrooms, since some of their tastes develop slowly). DO NOT SWALLOW, and try not to trip over anything. Spit the mushroom out, and rinse your mouth out thoroughly with water, being careful not to swallow.
- If you have tasted Lactarius piperatus, Tylopilus felleus, or another excruciatingly acrid or bitter mushroom, be prepared to regret the experience. Do not kiss anyone for several hours afterwards!