Herbal tinctures are not always made using ethanol as the solvent, though this is most commonly the case. Other solvents include vinegar, glycerol, diethyl ether and propylene glycol, not all of which can be used for internal consumption. Ethanol has the advantage of being an excellent solvent for both acidic and basic (alkaline) constituents.
Glycerine can also be used, but when used in tincturing fashion is generally a poorer solvent. Vinegar, being acidic, is a better solvent for obtaining alkaloids but a poorer solvent for acidic components. For individuals who choose not to ingest alcohol, non-alcoholic e,g., (glycerite) extracts offer an alternative for preparations meant to be taken internally.
Some solutions of volatile or nonvolatile substances are traditionally called spirits, regardless of whether obtained by distillation or not and whether or not they even contain alcohol. In chemistry, a tincture is a solution that has alcohol as its solvent.