A tincture is a plant steeped in alcohol-water for days to weeks and then strained; the alcohol percentage decides what is extracted, so spirit should be diluted to the intended strength by calculation, not by eye. To make 1 litre at 60% from 80% spirit, mix 750 mL of the spirit with 250 mL of water. Record the plant, weight, spirit strength and volume on the label, because the strength of the plant itself is the unknown.
Part of Organic Chemistry
Alcohol and water preparations of plant material, their strength control and storage.
Alcohol Strength Is The Main Variable
The carrier calls tinctures, produced by alcohol extraction of plant material, “the basis of most herbal medicine”. Alcohol dissolves both water-soluble and oil-soluble compounds (Solvent Extraction). The corpus’s Tincture Making page ties plant type to spirit strength, and Tinctures and Pharmacy Tinctures cover the herbal and dosing context; this article does not repeat their strength tables or doses.
Extracts are the family a tincture belongs to. Water extracts (infusions, decoctions) are short-lived and spoil; alcohol extracts keep, because strong enough alcohol also preserves them. Concentrated extracts, dried or boiled down, gain strength and lose the natural ceiling a dilute preparation has.
What You Need
- Spirit of known strength (check against a hydrometer or a reference; see Achieving 90%+ Purity). Use grain or sugar spirit, never an unidentified distillate: see Methanol Hazards for why the feedstock matters.
- Clean water.
- Dried plant identified with certainty.
- Glass jars with tight lids, dark glass or kept in the dark.
- A scale and a graduated measure.
Method: Making A Tincture At A Stated Strength
Step 1: Choose the strength from the tincture-making page for the plant.
Step 2: Dilute the spirit by the formula in the worked example below.
Step 3: Weigh the plant and measure the liquid so the ratio is recorded, for example 1 part plant by weight to 5 parts liquid by volume (an illustrative labelling convention).
Step 4: Steep sealed, shaking daily, for the time the corpus pages give.
Step 5: Strain, press, filter, bottle and label with plant, part, weights, volumes, spirit strength and date.
Worked Example: Diluting Spirit To A Target Strength
To get 1 litre at 60% from 80% spirit, use the dilution relation C1 × V1 = C2 × V2.
- V1 = C2 × V2 ÷ C1 = 60 × 1,000 mL ÷ 80 = 750 mL of the 80% spirit.
- Water to add: 1,000 − 750 = 250 mL.
- Check pure alcohol: 750 × 0.80 = 600 mL in 1,000 mL = 60%.
Mixing alcohol and water shrinks the total volume slightly, by a few per cent from general knowledge, so top up to the final mark with water in a measuring vessel instead of adding a fixed 250 mL. The strength is then close to, not exactly, the target.
Common Mistakes
- Making a tincture from an unidentified or mixed plant.
- Skipping the record, which makes the batch impossible to repeat or to dose.
- Using a distillate from a pectin-rich fruit feedstock as the solvent. It adds methanol to something meant to be swallowed.
- Treating a stronger tincture as better. Strength is a choice, and potency of the plant is still unknown (Standardization).
- Leaving it near children, since a tincture is also a bottle of strong alcohol.
Safety
The solvent burns and the preparation is a drug
Strong spirit is flammable: pour away from flames and store sealed. A tincture of a toxic plant (see Poisonous Plants) is far more dangerous than the tea: do not make tinctures of narrow-margin plants. Dose only from tested figures and see Dosage and Safety.
What’s Next
- Learn next: Antiseptic Compounds — alcohol and other preparations used on skin
- Combine with: Standardization — keeping batches comparable