Producing Ethanol (Alcohol) Powdered Extracts
With powdered extracts, the vast majority of herbs (referring here to medicinal plants, fungi, and other substances) are produced using a method called a hot water extract (read our page on this process here). However, for some specific applications, a second method is utilized to produce powdered extracts—ethanol (alcohol) extracts. This is very similar process as a hot water extraction, but with an ethanol extract, the two distinct extraction processes happen almost in reverse. Similar to hot water powdered extracts, when extracting using ethanol as the primary substrate, all soluble compounds are captured.
An ethanol powdered extract is used when those targeted compounds are more readily dissolved in ethanol (over water). For instance, while the polysaccharides present in Reishi (Ganoderma lucidum) are more readily extracted using the hot water process, the equally important triterpenes in Reishi are more readily extracted using ethanol.
Gathering Herbs and Preparing For Extraction
Before extraction begins, several steps need to be taken, including:
- The collection of raw materials (wild-harvesting, cultivation, et cetera);
- Sorting and selecting the raw materials for quality and then washing them;
- Grinding the raw materials and sieving the resulting powdered. This increases the surface area of the herbs to increase extraction.
When the herbs have been collected, selected, cleaned, and ground, the extraction process begins.
Stage One: Ethanol Processing
Ethanol (CH₃CH₂OH, ETOH) is the technical name for the alcohol that people drink (as seen on the right). Beer, wine, rum, and whiskey all contain ethanol.
Ethanol is produced using a variety of means, but in short, it involves the fermentation of a sugar by a yeast. With concentrated ethanol, the fermentation is then purified by distillation. To learn more ethanol, visit the Wikipedia entry of the subject.
When producing herbal extracts, ethanol has three advantages: It is relatively inert and non-toxic, it is an effective solvent, and it evaporates moisture.
In the ethanol step, the herbs are combined with ethanol and allowed to percolate. The exact concentration of ethanol (as a percentage of alcohol to water) and the length of time left to percolate will vary depending on what is being extracted and the desired extraction concentration.
Once the percolation is complete, the combination of herbs and alcohol is concentrated using a vacuum pump to the proper extraction ratio (10:1, 50:1, 200:1, et cetera). When the ratio is reached, the mixture continues its way to the following.
Stage Two: Water Precipitation
Here, in stage two, the concentration of herbs and alcohol from stage one are precipitated using water. Water is added to the mixture, and everything is reduced. This process transfers those compounds that have been dissolved in the alcohol back onto the solids. This way, when all of the liquid is removed, all extracted compounds are present in the resulting extract.
In short, stage two ensures a complete, full spectrum extract.
Once the the added water has been precipitated out, the mixture goes onto its finally processing: Drying. With drying, the extract is sprayed a temperature of between 70° and 100° Centigrade. When spray drying is complete, that powder is further refined by crushing, agitation, and sieving.
Different Ways of Extraction
When omitting the folk tradition of producing herbal extracts (including the usage of wines, medicinal oils and salves, and even foods like soups), there are three major methods for extracting plants, fungi, and other substances for their medicinal value. These are:
- Ethanol/alcohol powdered extracts (discussed above);
- Hot water powdered extracts (learn more here);
- Liquid (tincture) extracts (learn more here).
Ethanol powdered extracts, as seen in our Arctic Bear Wild Siberian Chaga Extract and in our Våren Forest Nettles Beta-Sitosterol Capsules, are an important tool in our toolbox for producing professional, clinical grade powdered extracts.
These extracts capture and concentrate the full-spectrum of compounds contained within the herbs they are produced from. To learn more about how these extracts have been utilized in the scientific literature and within scientific and medical research, visit academic sites like NCBI's PubMed or Google Scholar.