Several different solvents can be used to extract herbal phytochemicals, including ethanol, glycerine and vinegar, however which solvent should you look after for your herbal preparations and which will provide the best herbal quality extracts for you?
Ethanol (or alcohol) has been used since ancient times in the preparation herbal liquid preparations or herbal tinctures. A varied range of phytochemicals were found to be successfully extracted using a solution of water and ethanol. A wide range of different ethanol percentages can be used to extract phytochemicals from medicinal herbs and these percentages should be optimized according with the herb used for extraction. For example, 25% of ethanol is thought to successfully extract water-soluble herbal components such as tannins, mucilage and some glycosides (e.g. flavonoids and a some saponins). Whereas 45% to 60% is though to successfully extract alkaloids, most saponins, essential oils, alkaloids and some glycosides and 90% ethanol percentages can extract oleoresins and resins. Several methods can be used for the preparation of herbal tinctures these include the folk method, the ratio method and percolation.
In general, 40% to 60% ethanol was found to have the maximum effectiveness for the extraction of the active components of a diversity of herbs, however each herb needs to be considered individually for better extraction conditions.
You may be concerned with ethanol exposure especially if you are pregnant or have children. However, the ethanol quantities present in alcoholic herbal preparations are very reduced and rapidly metabolized by the liver therefore its effect might not be measurable in the blood.
Glycerol or glycerine as it is commercially is used with water in herbal liquid preparations as an alternative to ethanol and water. Glycerites or glycetracts can be used for the extraction of water-soluble constituents. However, glycerol is not a good solvent choice to the extraction of numerous herbal constituents (e.g. resins, essential oils and saponins), the final preparations are less stable than the alcoholic herbal preparations and the preparation might be difficult due to viscosity. Like ethanol, the glycerol intake in herbal preparations is so small that no negative side effects can occur. Glycerites can be a great extract choice specially if you are pregnant or for your children.
- 3. Vinegar
Vinegar can be used instead of ethanol or glycerol for the extraction of minerals present in herbs. Herbal vinegars don’t have the medicinal properties of alcoholic extractions or herbal tinctures but you use them as gentle tonics.
Alternatively, honey can be used to infuse herbs instead of ethanol, glycerol or vinegar, but as vinegar it is not as medicinally potent as alcoholic extractions or herbal tinctures. Honey herbal infusions can be named as syrups, or elixir if mixed with ethanol, or oxymel if the herbs are mixed with honey and vinegar.
In conclusion, alcoholic extractions or herbal tinctures are more medicinally potent, are more stable with longer shelf lives and may be the best option for you. However, alcohol sensitive groups such as pregnant woman and small children, people suffering from alcoholism or for religion reasons can use herbal glycerites as the next best medicinal choice after ethanol.