There are many ways to extract CBD oil. The purpose of extraction is to create cannabinoids that are highly concentrated for human consumption and that’s why ethanol extraction is the best CBD oil extraction method.
Ethanol extraction involves introducing the ethanol to the hemp plant in order to extract the cannabinoids. Ethanol extraction can produce cannabis oil with up to 99 percent purity.
Ethanol is more common than people think. Ethanol can be found in grain alcohol made by fermenting plant sugars from agricultural crops. Ethanol (C2H5OH), also known as ethyl alcohol, is a colorless and flammable liquid that can produce intoxication, be used for fuel, and also be used as a solvent. Ethanol can be fermented from different crops, but corn is the main source of ethanol in the U.S.
Ethanol extraction can be performed under warm or cold temperatures. Generally, raw and ground-up cannabis material (dry or frozen) is soaked in pre-chilled ethanol for a certain amount of time to separate the plant’s trichomes from the plant matter. For larger batches, room temperature or cooled ethanol can improve the quality of cannabinoids and terpenes in cannabis and hemp extraction.
After the initial extraction process using food grade ethanol, the solution is filtered and the ethanol is purged from the extract. Post-processing techniques gently remove ethanol from the extracts through evaporation. Ethanol may be removed with rotary evaporators, falling film evaporators, or a vacuum distillation system.
Winterization is a term used to describe the process of removing impurities such as plant lipids, chlorophyll, waxes, and fats from the oil. Chilling the oil and ethanol solution can cause these undesirable compounds to separate (precipitate) and rise to the top for easier removal. The cooling process can be performed in freezers, cold rooms, or other cooling equipment.
Keep in mind, ethanol has a higher boiling point than butane or propane. Because of its relatively higher boiling point, many of the terpenes that give cannabis the desirable flavors and aromas that many consumers enjoy, are lost in the ethanol extraction process. The inevitable loss in terpenes from the ethanol process also diminishes the entourage effect of the final ethanol extract product when compared to BHO extraction. Regardless of ethanol’s weaknesses, large-scale throughput and financing can easily overcome equipment limitations.
Ethanol extracts can also undergo a final polishing phase where adsorbents can be used to lighten the oil’s hue and improve the translucence of the extract. Popular adsorbents such as activated charcoal and bleaching clays can improve not only the color but also the quality of ethanol concentrates.
The residual ethanol is evaporated, condensed, and reused in the closed-loop extraction system to increase cost-efficiency and throughput. All of these operations take place in a lab-grade facility with adequate ventilation and storage areas.