Key takeaways
- Alcohol extraction uses food-grade ethanol, usually mixed with water.
- It draws out compounds such as triterpenes and sterols that dissolve poorly in water.
- Strong alcohol makes polysaccharides precipitate, so dual extracts need careful balancing.
- Alcohol also preserves a tincture, so no added preservatives are needed.
- Tinctures contain alcohol; the amount is stated on the label.
Alcohol extraction is the other half of most mushroom tinctures. It reaches compounds that hot water leaves behind, and it keeps the finished tincture stable. This article explains how it works, what it draws out and what alcohol means for the product you use.
Why alcohol?
Ethanol is less polar than water, so it dissolves a different range of compounds. In practice it is usually used as a mixture with water, and adjusting the proportion changes what is extracted. Stronger alcohol favours less polar compounds; weaker mixtures behave more like water. See How Solvent Choice Changes What Is Extracted.
What alcohol draws out
- Triterpenes, such as the ganoderic acids in Reishi.
- Sterols, such as ergosterol.
- Some phenolic compounds and other less polar molecules.
Polysaccharides, by contrast, don’t dissolve well in strong alcohol. In fact, adding alcohol to a water extract is a standard laboratory method for making polysaccharides precipitate out of solution. This is one reason why the order and proportions of a dual extract need care.
How alcohol extraction is done
The most common approach is maceration: dried, ground mushroom is steeped in the alcohol mixture for a period of days or weeks, agitated from time to time, then filtered. Percolation, where the solvent passes slowly through the material, is another option.
Alcohol as a preservative
Alcohol does a second job: it preserves the tincture. With sufficient alcohol, a tincture resists microbial spoilage without needing added preservatives, which is why it keeps well once opened. The alcohol content of a tincture is always stated on its label. See Mushroom Extract Shelf Life and Storage.
What “plant-derived ethanol” means
Food-grade ethanol is made by fermenting plant material and then distilling it. “Plant-derived” simply tells you its origin. It is the same kind of alcohol found in drinks, used here as a solvent and preservative.
Why not glycerine?
Some tinctures use glycerine instead of alcohol. Glycerine avoids alcohol, but it has different solvent properties and much weaker preserving power, so the resulting extract is a different product.
Alcohol in the finished product
A typical serving of a tincture is small, but it does contain alcohol. If you avoid alcohol for any reason, including pregnancy, religious reasons, recovery or medication, check the label and consider whether a tincture is right for you. See How Much Alcohol Is in a Mushroom Tincture?
What alcohol misses
On its own, alcohol extraction captures relatively little of the polysaccharide content of mushrooms. That’s why it is usually paired with hot water extraction to make a dual extract.
How we use alcohol extraction
We extract our UK-grown fruiting bodies and wild Finnish chaga in plant-derived ethanol, separately from our hot water extract, and then combine the two. The ethanol extracts the alcohol-soluble compounds and preserves the finished tincture, so nothing else needs to be added.
