Turn over any of our mushroom tinctures and you'll find just three ingredients: the mushroom, spring water and food-grade ethanol at 20%. Each one is there for a reason.
Water and ethanol each dissolve a different set of the mushroom's compounds, so using both (a dual extraction) is the only way to capture the full spectrum. Ethanol then does a second job: it naturally preserves the finished extract. And at 20%, the amount of alcohol in a single 1ml serving is genuinely tiny, as we'll show with the numbers below.
This post is a companion to Ultrasonic Extraction and Vacuum Distillation: The Gentle Science Behind a Better Mushroom Extract, which explains the equipment and process we use.
Mushrooms contain two families of compounds
Medicinal mushrooms hold both water-soluble and alcohol-soluble compounds, and no single solvent captures both well (Mountain Rose Herbs).
| Compound group | Dissolves best in | Examples |
|---|---|---|
| Polysaccharides, including 1,3-1,6 beta-glucans | Water | The beta-glucans in Turkey Tail, Lion's Mane, Reishi and Chaga |
| Triterpenes and other terpenoids | Ethanol | Ganoderic acids in Reishi; erinacines in Lion's Mane |
| Phenolic compounds and sterols | Ethanol (and ethanol–water blends) | Antioxidant polyphenols in Chaga; ergosterol |
All of these are locked behind chitin cell walls, which is why the extraction method matters as much as the solvent. A combination of hot water and alcohol is widely preferred for capturing both the polysaccharides and the alcohol-soluble compounds (Raw Forest Foods).
Why ethanol is such a good solvent
Ethanol is one of the most versatile, safe and practical solvents there is for natural extracts. Herbalists and pharmacists have relied on it for centuries, and there are solid chemical reasons why.
- It works on both sides of the fence. An ethanol molecule has a water-loving end (its hydroxyl group) and an oil-loving end (its short carbon chain). That lets it dissolve compounds that water alone can't touch, like triterpenes and resins, while still handling many moderately polar compounds. It's an excellent solvent for both acidic and alkaline constituents (EPFL Graph Search).
- It mixes perfectly with water. Ethanol and water blend in any ratio, so the solvent can be tuned precisely to the compounds being targeted. Tinctures are often made with both, because each dissolves what the other can't.
- It's food-safe. Food-grade ethanol is the same alcohol found in everyday foods and drinks. Many alternative solvents used in industry are not safe to consume.
- It's easy to remove. Ethanol has a low boiling point, so it can be gently taken out under vacuum at around 40°C. That makes it simple to concentrate an extract and set its final strength, without high heat.
- It preserves the finished product. More on this below.
By comparison, glycerine (used to make "glycerites") is generally a weaker solvent than ethanol, and vinegar extracts some compound types well but others poorly.
Why water extraction is essential for mushrooms
For mushrooms, an alcohol-only extract misses the main event. The beta-glucans that mushrooms are best known for are water-soluble, so without a water extraction step they're largely left behind in the spent mushroom.
This is what sets mushrooms apart from many herbs. A lot of herbal tinctures can be made with alcohol alone. But mushrooms have been prepared as teas, broths and decoctions for centuries, and for good reason: water, with the help of time and heat (or, in our case, ultrasound), opens up the chitin cell walls and draws out the polysaccharides.
There's a second, less obvious reason. High concentrations of ethanol cause polysaccharides to drop out of solution. Scientists actually use this to isolate beta-glucans in the lab: one mushroom study precipitated its polysaccharides using 80% ethanol (Aguiló-Aguayo et al., 2017). Herbal educators have warned that some dual extracts lose beta-glucans this way, when the polysaccharides settle out in strong alcohol and get strained off with the solids (Chimelski, Fungi Medicine).
That's one reason our finished tinctures are mostly water, with ethanol at just 20%: enough to dissolve and preserve, but low enough to keep the water-soluble compounds where they belong, in the bottle.
Ethanol: a natural preservative
A water-only mushroom extract is essentially a nutrient-rich broth, and broths spoil. Left at room temperature, bacteria, yeasts and moulds would soon start growing in it.
Ethanol prevents that. It is antimicrobial, so it acts as a natural preservative (Wikipedia: Tincture). In herbal practice, a tincture should contain at least 20% alcohol to keep it preserved, and at that level it generally stays stable at room temperature.
That's exactly why we use 20%. It means:
- No synthetic preservatives. The ethanol does the job on its own.
- No fridge needed. Store the bottle somewhere cool and dark, away from direct sunlight.
- A stable product from the first drop to the last. A 50ml bottle lasts around 50 days at 1ml a day, and it stays protected the whole time.
It's the minimum needed to keep the extract safe and stable, and no more.
How much alcohol is actually in a serving?
A 1ml serving of a 20% tincture contains about 0.16g of alcohol, roughly 1/75th of a South African standard drink.
Here's the maths. A 1ml serving at 20% contains 0.2ml of pure ethanol. Ethanol weighs about 0.79g per ml, so that's around 0.16 grams. In South Africa, one standard drink is defined as 12g of pure alcohol (Africa Check).
To put that in perspective, many everyday foods contain small amounts of naturally occurring alcohol from fermentation. A 2016 study in the Journal of Analytical Toxicology found ethanol in orange, apple and grape juice, and up to 1.2g per 100g in some packaged bread rolls (Tasting Table; summary of findings).
| Item | Approx. alcohol (g) |
|---|---|
| One SA standard drink (about 300ml of 5% beer) | 12 |
| A whole 50ml bottle of our tincture (50 servings) | 7.9 |
| A 50g sweet bread roll (high end) | 0.6 |
| A 250ml glass of orange juice (high end) | 0.18 |
| One 1ml serving of our tincture | 0.16 |
In other words, a full serving contains about as much alcohol as a glass of orange juice can, and even the entire bottle holds less alcohol than a single standard drink.
Want to avoid even that? Add your daily dose to a little warm water or tea and let it stand for a minute or two. The warmth helps some of the alcohol evaporate before you drink it. If you avoid alcohol completely, for any reason, please check with your healthcare provider first.
Frequently asked questions
Why not just use alcohol, like many herbal tinctures?
Because mushrooms' beta-glucans are water-soluble. An alcohol-only extract leaves most of them behind, and strong alcohol can even push them out of solution.
Why not just use water?
Water misses the alcohol-soluble compounds, such as Reishi's triterpenes, and a water-only extract would spoil without added preservatives.
Will a serving make me feel the alcohol?
A 1ml serving contains about 0.16g of alcohol, around 1/75th of a standard drink. That's in the same range as a glass of orange juice.
Why 20% and not higher?
Around 20% is the commonly accepted minimum to keep a tincture preserved at room temperature. Going higher adds alcohol without adding benefit, and keeping it low helps keep water-soluble compounds in solution.
Do I need to keep it in the fridge?
No. The ethanol keeps it stable. Store it somewhere cool and dark.
References
- How to Make a Mushroom Double Extraction. Mountain Rose Herbs.
- Functional Mushroom and Fungi Extraction. Raw Forest Foods.
- Tincture. EPFL Graph Search.
- Tincture. Wikipedia.
- Aguiló-Aguayo I et al. (2017). Ultrasound assisted extraction of polysaccharides from mushroom by-products.
- Chimelski. Fungi Medicine (presentation).
- South Africans are not the world's biggest alcohol consumers. Africa Check.
- How much booze is "too much" booze? BusinessTech.
- The Scientific Reason Some Fruit Juices Contain Alcohol. Tasting Table (reporting Gorgus et al., 2016, Journal of Analytical Toxicology).
Disclaimer: This article is for educational purposes only. Our products are not intended to diagnose, treat, cure or prevent any disease. Always consult a qualified healthcare professional before using any herbal or dietary supplement, especially if you are pregnant, nursing or on medication.
May the Fungi be with you!