Part one of “Mushromatherapy” introduced some of the more ubiquitous scent molecules responsible for characteristic aromas of some of our (making an assumption here) favorite edible and medicinal mushrooms.  The article also delved into what these volatile compounds do for the mushrooms and what they may potentially do for us.  This time, we’ll geek out a bit more on mushroom scent and perfumery and, for anyone who cares, touch on what makes certain mushrooms smell so good.                                                                                                                                                                                                                                                                                                                                               

Experiments with mushroom aromatics                                                                                                                                               

Mushroom aromatics can vary widely based on where a particular mushroom grows, what time of year it is, what it’s growing on, how old the fruiting body is, whether it’s raw or cooked and other factors.   Along these lines, I’ve found Oyster Mushrooms in the wild with the loveliest scent of anise and almond.  But growing them from kit?  Zero anise, zero almond.  Given that the chemicals largely responsible for the scent — anisaldehyde and benzaldehyde — may protect the mushroom from infection (1, 2) and UV radiation (3), it seems like there’s little need for them in coddled, kit-grown Oysters.                                                                                                                                                                                   

As mentioned in part one of this series, there are some commercial mushroom-based scents out there, but not many. Mandy Aftel’s Cepes and Tuberose is one, and she also offers a Bolete absolute (4). Cepes is another name for Bolete (aka Porcini), which has a big, rich, earthy scent (especially after it’s been roasted), while tuberose is sweat, creamy and strongly flora.

 

A note on perfumery notes before getting back to mushroom scents. The concept of a musical scale is often used in perfume blending, to make a balanced, nuanced blend.  Along these lines, top or high notes are those aromatics that evaporate first from a blend, because of their smaller molecular size. One could say that they have a higher vibration. At the other end of the spectrum are the base notes that are the heaviest aromatics, molecularly speaking.  These evaporate the slowest and, generally, ground the blend. In between are the middle notes that make up the body of the blend and connect top and bottom notes.

 

If you’ve encountered heavy base oils like Vetiver or Nutgrass, you might assume that base notes are the most intensely smelling and tend towards deep, earthy scents. In reality, some base notes aren’t super intense, like Elemi and Myrrh, and others are even sweet (Vanilla).  One might also assume that top notes tend towards lighter, floral, sweet or citrusy scents.  But, if you’ve smelled Eucalyptus oil, a top note, you know it’s anything but light or floral or sweet.   So, along these lines, those compounds such as octenol that are largely responsible for the mushroomy, earthy scents of our fungal friends are….wait for it…..top notes!  They’re small molecules and, hence, evaporate quickly.  So, top notes despite the funky, earthy scent. I mentioned in the first article of this 2 part series that octenol (1-octen-3-ol for you chem nerds) is the most ubiquitous of mushroom aromatics and is an 8-carbon compound derived from linoleic acid oxidation. It and other so called “C8” compounds are found in mushrooms here, there and everywhere.

Despite all this chemistry nonsense, many mushrooms do indeed have a great, earthy scent upon which to layer sweet, floral, citrusy or even sharp scents. Like some of the really “dirty” smelling base oils out there, some mushroom scents may not be super appealing on their own but are just what’s needed to make a blend interesting. Though you still want to add in just a small amount of a true base note to help preserve the blend while not overwhelming the mushroom’s scent.                                                                                                                                               

So, am initial foray into playing with mushroom aromatics….   Of course after proposing this class and getting enthused about the topic, we in the Southern Rockies proceeded to have the shittiest mushroom season.  Thus, no Chanterelles, Boletes, Oyster Mushrooms, Coral Mushrooms and other yummy smelling ones for experiments. The very few of these encountered, I left alone so they could do their thing sporulating. So, conks it was for the most part. These tough, woody fruiting bodies are perennial, and so were available despite a dry (and  fiery!) year. 

Mushrooms don’t have nearly the volatile oil content that aromatic plants do, so the focus was not on extracting pure oils.  Not set up for that, anyway.  Instead the conks were used for making hydrosols and infused oils.   

First, distillations.  I’m not a great distiller. But did generate some mushroomy hydrosols either via a stove top set-up or with a microwave distiller.  Hydrosols will contain water-soluble aromatics and, generally, very small amounts of essential oil droplets in suspension.                                                                                                                                                    

Then, mushroom-infused oils. In contrast to hydrosols, an infused oil will contain only the fat-soluble aromatics. So a hydrosol and an infused oil of the same mushroom won’t necessarily smell the same, though there may be similarities.  Anyway, the infused oils are produced in 1 of 2 ways. One is a modified version of Michael Moore’s way of making Rosemary-infused oil.   The (relatively dry) are chopped then blended on medium/high (the only functioning setting on my blender) with expeller-pressed grapeseed oil until the oil warmed up (4-5 min). (I’d prefer jojoba but I’m too cheap to buy it in enough quantity.) The mixes are then heated on low (below 110°F) in a double boiler for a half hour. They’re filtered after sitting overnight at room temperature, then after one more day of sitting, the oil is decanted from any remaining crud at the bottom of the jar.  Alternatively, the oils are made via the old fashioned window sill method, with 4-6 weeks of infusion.                                                                                                           

So, the results!                                                                                                                                                                                            

Artist’s Conk (Ganoderma applanatum) hydrosol and infused oil are woody and earthy with a note of fermentation.  There’s a great report on Artist’s Conk steam distillation at Reishi and Roses, a wonderful and informative blog on mushrooms and mushroom medicine (5). The author actually obtained a lardy, aromatic substance after a couple of hours that I didn’t manage to capture for Artist’s Conk, in either my janky stove top distillation or in the microwave distiller. She mentioned that the aroma was extremely sedating.  I’ll have to look more into this with mine, but I’m pretty hard to sedate!                                                                                                                                                                            

Not surprisingly, octenol is a major aromatic component of Artist’s Conk (6). Octenol has 2 forms based on structural orientation that smell different. The form in Artist’s Conk octenol is described as “genuine mushroom”, earthy, fresh, with some fruitiness (7).  Phenylacetaldehyde was another major component among the 22 aromatics identified from distillation (6), and its odor is described as slightly earthy, fermented, green, cocoa, sweet and floral. Some of the more prevalent terpenes include included ?-terpinene (woody, lemon, oily, herbal (7)) and d-limonene (citrus, (7))(6).    

False Tinder Polypore/Aspen Bracket (Phellinus tremulae) – I was thrilled to recently stumble upon the name “Aspen Bracket” for this mushroom. That’s way easier to say than “False Tinder Polypore”.  Plus, having “false” as part of a name kinda sucks.                                                                                                                                                                                 

Anyway, Aspen Bracket is a common conk around here in the Southern Rockies because Aspen trees are common around here.  The “tremulae” part of Phellinus tremulae reflects that fact that Quaking Aspens (Populus tremuloides) are its host.  This one did not yield as strong an aroma as Artist’s Conk by distillation or oil infusion. Though sometimes when I harvested this conk for medicinal preparations, it has a faint wintergreen scent. I’ve even convinced myself that one of the hydrosol fractions had an ever-so-small touch o’ wintergreen. Though I don’t notice it in the infused oil.  There is a scent of clean hamster litter (you know, the curled wood shaving-type…) The wintergreen thing is in agreement with research showing that various Phellinus species contain methyl benzoate and methyl salicylate (8). Aspen Bracket may be picking up at least one of these from its host, given that Aspens contain methyl salicylate and compounds related to methyl-benzoate (9).    

 

Red Belted Conk (Fomitopsis sp ) – The Red Belted Conks around here generally referred to as Fomitopsis pinicola, but recent genetic analyses have found that F. pinicola is restricted to Eurasia and that we have 4 distinct species here in North America that look a hell of a lot like and are closely related to F. pinicola (10). I’m mentioning this because the studies looking into aromatics were done on European F. pinicola.                                                                                             

Anyways, Red Belted Conk has a more of a woody scent than mushroomy one (though, yes, it has octenol (11)). There is a sharp, juicy note that’s super noticeable especially when chopping it up. There’s a bit of funkiness to it. There was a tallow-like, whitish opaque layer that came out of the oil infusion, and the aroma is stronger in this than in the oil itself. Aside from octenol, ?-barbatene is another chemical that’s considered a main contributor to the odor of Red Belted Conk (11), though I’ve not yet found a description of how ?-barbatene itself smells. Maybe sharp, juicy and woody???   Red Belted Conk also has several terpenes, including ? – pinene and limonene (11), familiar to folks who work with Pine or Citrus oils.   The aroma of Red Belted Conk attracts wood-living beetles (11). Maybe I’ll be dive bombed by beetles if I wear my RBC blend in the woods. I’l keep you posted.                                                                             

Shaggy Scalycap (Pholiotta squarrosa)  Something that’s not a conk!  One of the few soft mushrooms I encountered in a very dry season. The hydrosol pretty well reflects the scent of the fresh mushroom:  A strong and minerally, dirt-like scent. This species sometimes has a garlic scent, but I’ve not yet noticed that in those I’ve encountered here.  Of course, octenol is a major aromatic (12) as with most, if not all, mushrooms.   Other volatiles include methyl 2-foroate (13), described as fruit, mushroom, fungus, tobacco and sweet (7), and geosmin (13)(earthy, freshly plowed soil (7))  Freshly-plowed soil really describes it to a T!                                                                                                                                    

Almond Mushroom (Agaricus blazei) – OK, the dried Almond Mushrooms were bought online. . They have a very strong mushroom scent, but none of the strong almond scent that they’re known for. I distilled and oil extracted them anyway, both of which smell more or less the dried mushrooms. Like mushroom gravy on steroids.

On to blending… At the moment, I’m blending mushroom-infused oils with small amounts of essential oils to play around with either complementing or highlighting the mushroom aromas.                                                                              

Current blends                                                                                                                                                                                         

1) Artist’s Conk infused oil plus essential oils of Geranium, Bergamot and Lavandin. The result is a sweet and earthy blend with citrus notes to lighten it up a bit. 

2) Red Belted Conk infused oil plus essential oils of Juniper, Cypress, Fir and Coriander. This was a woodsy blend to try and reflect the forest where the conks were found. 

3) Aspen Bracket infused oil plus essential oils of Davana, Petitgrain and Lavandin. The goal here was to make an airier blend to work with the lighter scent of this conk. The airy scent also reflects that these conks are often way up in the tree. 

4) Almond Mushroom (lacking the almond scent!) infused oil plus essential oils of Black Pepper, Cardamom, Mandarin, Tangerine and Ylang Ylang. This the opposite of the Aspen Bracket Blend. This one has bold spicy and citrusy scents added to complement the ridiculously-strong mushroom scent.

                                                                                                                                                                                                      Characteristic aromatics in popular edible and medicinal mushrooms                                                                                            

Chanterelles (Cantharellus cibarius)

Of course these are on the list. Chanterelles have a mild apricot-like aroma that matches their apricot color. The Chanterelles here in Colorado smell more or less like those I used to pick outside of Seattle, despite the fact that the habitat couldn’t be more different. (Here, they peek out from under rocks in sunny spots within mixed Aspen/Conifer woods. In Washington they like the deep duff of dense Doug Fir forests.                                                                                  

Although Chanterelles have very low levels of aromatics overall, there are dozens of volatile compounds that contribute to their distinctive scent (14). Those present in the highest amounts include the ever-present C8 compounds such as octenol, though there are several aromatic alcohols and aldehydes found in Chanterelles that are used, in purified form, in the perfumery industry (7).  Some Chanterelle aromatics that you may even be familiar with from Lavender, Peppermint and Eucalyptus.                                                                                                                           

Here are a handful of aromatics that make Chanterelles smell good (not a comprehensive list)(7, 14-17): 

Hexanal  – The scent —  which you may have gotten to sniff in very diluted form in class at the Good Medicine Confluence (GMC) — is described as citrusy, apple-like, woody, grassy, green, fresh, and/or vegetable-like.  Chemical names that end in “al” are aldehydes, which generally have fruity, sweet scents.

Hexanol – This is another you may have smelled in class at the GMC. Hexanol is described as  freshly-cut grass, fruity, apple, sweet, oily, herbal, green, wine-like, goaty(!) and ethereal.  “Ethereal”  means like ether, which has a sickly sweet scent. Though some folks use ethereal to mean light and airy. By the way, chemicals that end in “ol” are alcohols. The scent of alcohols can vary widely from sweet to sharp to medicinal.  

Heptanal – This one is described as fruity, solvent-like and “pen”. (Sharpie pens do smell good.)  Heptanal is used as source material for perfumery ingredients (18). Heptanal, like octenol, is secreted by the skin and is a mosquito attractant (19).  Perfume and mosquito attractant? Hmmmmm….

Heptanol – A volatile with sweet, fruity, cucumber-like notes, and also “cellar”.  Heptanol blocks signal transmission gap junctions (20), inhibiting signaling between cells. As such, it may have applications with respect to tremors and seizures (20).

(E)-2-nonenol – This one has my favorite description so far: ”Cucumber, old books, cardboard, paint, air mattress (?!?!). 

? -copaene – This is one of the major contributors to the distinctive flavor of Chanterelles.  It’s scent is noted as woody, spicy, honey-like. It’s also in Eucalyptus, Star Anise, Geranium Basil, Bay and a whole slew of other plants. 

Alpha-humulene – Another major flavor component of Chanterelles. It smells woody, clove-like, and like ocean water. This is in many members of the Mint family, along with Valerian, Black Pepper and Pine needles. 

Beta-caryophyllene – Yet another big one in Chanterelle flavor. It smells sweet, fruity, spicy, woody, clove-like, and peppery) and is also found in Carrot, Clary Sage, Lavender and multiple citruses. 

Eucalpytol – This is described as minty, herbal, camphorus, eucalyptus-like, strong and/or fresh. Can you guess what plant this is in?                                                                                                                                                                                            

Matsutake (Trichloma species)

Matsutake means “Pine Mushroom” and it grows, shockingly enough, in Pine forests.  (“Take” means mushroom in Japan. As in Maitake and Shiitake).  Matsutake is much sought after because of its distinctive, spicy scent and strong flavor.                                                                                                                                                                                                                                                                                                                                                                                                                  The most notable aromatics include a variety of C8 compounds, along with an interesting collection of other aromatics only some of which I’m including here (7, 21-23): 

Methyl-cinnamate – This is part of the distinctive scent of Matsutake. It’s described as balsamic, strawberry, cherry, fruity, cinnamon, spicy and sweet. Methyl-cinnamate plays a role in both mushroom metabolism and protection from predation (except from predation by us, apparently). 

Phenylacetaldehyde – Slightly earthy, fermented, green, cocoa, sweet and floral. Also in Artist’s Conk (and, if memory serves, in some species of Oyster Mushroom).  

Terpineol – A major aromatic in Pine that smells like….Pine.  I wonder if the mushroom picks this one up from its host?

Methional – This is pretty common mushroom aromatic, described as “baked potato”. 

Acetoin – A ketone with a buttery scent. Seems like it would go well with methional. 

(E)-2-decanal  – Smells like orange, of all things…                                                                                                                              

Oyster Mushrooms (Pleurotus species)

Another prized edible with lots of medicinal uses…   Yes, it’s loaded with C8 aromatics (and there’s a “C9”, nonanol, that smells like fruit). And don’t forget about the aforementioned anisealdehyde and benzaldehyde.  Hexanol (see Chanterelles) is also prevalent.                                                                                                                                                            

Oyster Mushroom alcohol extracts are active against multiple drug resistant pathogenic bacteria, with the aromatics likely being a part of this…especially anisealdehyde (1, 24).                                                                                                          

This is one of the best studied mushrooms in terms of aromatics, and many have been isolated from various species of Oyster Mushroom. Here are a few more (1, 7, 25, 26):

Acetaldehyde – Like many aromatics discussed here, in high enough levels, acetaldehyde is toxic, though commonly used in lower levels as flavoring in foods and in perfumery. In larger amounts in the body, it can have a corrosive effect on the tissues and has narcotic-like effects (27). Interesting that the FDA has given it GRAS (generally recognized as safe) status. Its odor is ethereal, sharp, fruity, green and penetrating. 

Gamma-butyrolactone – This one is described as creamy, sweet, caramel, peach, milky and fatty. Sounds good!

Beta-bisabolene – A sesquiterpene with a balsamic, woody scent.  Sesquiterpenes are heavy scent molecules (base notes!). 

2-pentylfuran – An ingredient used for flavor, it’s scent is noted as sweet, fruity, caramel, green, earthy, beany, waxy, vegetable and metallic. 

2-undecanone – Another delicious sounding one, with floral, fruity, pineapple, creamy, fatty, waxy and cheesy notes. Almost sounds like a wine description…                                                                                                                                            

King Bolete (Boletus edulis)

Yes, C8s. They contribute to the mushroomy, buttery and nutty flavor and scent of Boletes (aka. Porcini). As usual with mushrooms, King Boletes harvested from different regions have somewhat different scent profiles (28).   They also have some level of benzaldehyde and anisaldehyde, found in either fresh or frozen fruiting bodies (29).                  

Some other interesting Bolete volatiles (16, 28, 29):

2-propenoic acid – This gives a tart, acrid scent to Boletes.

Vanillin – This aldehyde is a major contributor to the scent of Vanilla beans. Though I can’t say I’ve ever noticed my bolete harvest smelling remotely Vanilla-like. 

Toluene – Yes, as in paint thinner.  Doesn’t sound so appetizing. Toluene, a solvent, is a benzene-derivative with a sharp scent similar to that of benzene (sweet, gasoline-like).

Euganol – A terpene that is largely responsible for the scent of Cloves and is also prevalent in Cinnamon, Basil, Bay and Nutmeg.  If you can think of the smell of Cloves, then you know just what eugenol smells like. 

Valeric acid – Named for Valerian and described as rancid, sweaty, sour, tobacco, cheesy with slight fruit notes. 

Putrescine – Can you guess how this smells, based on its name? Putrescine, charmingly enough, is a fatty acid derivative that, aside from Boletes, is found in decaying corpses as their fats decompose (30).  Turn on the range, it’s time to roast some Boletes!  Actually, Boletes do taste really good despite this component. I hope I haven’t put you off them….

                                                                                                                                                                                                        Truffles (Tuber species)

Truffles should obviously be included here but I’ve no experience with them other than Black Truffle oil…basically olive oil that’s had a Black Truffle waved over it at some point.

Truffles are really complex, aromatically speaking, more than 200 different scent molecules identified so far (31).  Some of the aromatics responsible for the distinctive Truffle scent comes from resident bacteria rather than from the truffle itself (24)!                                                                                                                                                                              

Some of the aromatics in Truffles include (31, 32):

2-methylbutanal – Smells like chocolate. That sounds way better than rotting corpse. 

Methional – Baked Potato! Here it is again!

Isobutanol – Not to be confused with rubbing alcohol (isopropanol).  Described as ethereal and winey. Also as “cortex” but I don’t know what the hell that means. Maybe it’s a typo.  (Can you tell I’m getting loopy tonight?) 

p-cymene – Woody, fresh, citrus, spice, harsh.

Cedrol – Woody, dry, soft, sweet. You are familiar with this scent if you’ve ever worked with Cedarwood.

Hydrogen sulfide – Rotten eggs.  Hydrogen sulfide is a big part of why farts smell like they do.                                               

OK, I think I’ve tortured you enough mushroom aroma. Hopefully this gets you experimenting yourself with mushroom scents whether in your cooking or perfume making. 

~~~

Content © Dr. Anna Marija Helt, Osadha Natural Health, LLC. Permission to republish any of the articles or videos in full or in part online or in print must be granted by the author in writing.

The articles and videos on this website for educational purposes only & have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease or to substitute for advice from a licensed healthcare provider.

References

1) Shen, H-S, et al (2017) Antimicrobials from mushrooms for assuring food safely. Comp Rev Food Sci Food Safety. 16:316-329.

2) Verma, RS et al (2017) Natural benzaldehyde from Prunus persica (L.) Batsch. Int J Food Prop. 20(52):S1259-63.

3) Nitoda, T, et al (2007) Anisaldehyde, a Melanogenesis Potentiator. Z Naturforsch. 62(1-2):143-9.

4) https://www.aftelier.com/Cepes-Absolute-p/bot-abs-cepes.htm

5) Sitkof, A (2015) Distillations on Ganoderma applanatum. Reishi and Roses. https://reishiandrosesbotanicals.com/2015/08/10/distillations-on-ganoderma-applanatum/.

6) Campos, F, et al (2007) Volatile Metabolites From the Wood-inhabiting Fungi Bjerkandera adusta, Ganoderma applanatum, and Stereum hirsutum. J Essential Oil Res. 22(2):116-118.  

7) The Good Scents Company Information System http://www.thegoodscentscompany.com/

8) Collins RP & AF Halim (1972) An analysis of the odorous constituents produced by various species of Phellinus  Can J Microbiol. 18(1): 65-66

9) Ayer, WA & ER Cruz (1995) 2-Carbomethoxyoxepin: 1-Carbomethoxybenzene 1,2-Oxide and the Biosynthesis of Methyl Salicylate in Phellinus tremulae. J Nat Prod

10) Haight, JE, et al (2016) Phylogeny of Fomitopsis pinicola: a species complex. Mycologia. 108(5):925-38.

11) Faldt, J, et al (1999) Volatiles of Bracket Fungi Fomitopsis pinicola andFomes fomentarius and Their Functions as Insect Attractants.  J. Chem Ecol. 25(3):567-90.

12) Dijkstra, F (1976) Studies on mushroom flavours 3. Some flavour compounds in fresh, canned and dried edible mushrooms. Zeitschrift für Le0bensmittel-Untersuchung und -Forschung 160(4):401-5.

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