Although there are several ways to extract CBD from the hemp plant, the two that are most common are ethanol extraction and CO2 extraction. Both have advantages and disadvantages, and both are capable of producing a first-rate product, but it’s important to know the difference.
When you want to extract CBD oil from hemp using ethanol extraction, the first thing you do is heat the plant material to achieve something called decarboxylation (that’s the removal of carbon atoms from a carbon chain). That leaves you with a fine, green powder that is subsequently soaked in a solvent, which in this case is ethanol. After a while, the solution is filtered, the liquid separates from the plant matter and eventually, the ethanol evaporates.
One of the arguments in favor of ethanol extraction is that it maintains the chemical ratios that occur naturally in hemp plants. So you get the terpenes and the flavonoids that support CBD, and you get them in just the right amounts. Ethanol extraction also efficiently extracts chlorophyll, which is both a plus and a minus. Chlorophyll has many health benefits—but at the same time, it’s kind of bitter and grassy tasting, and therefore not to everyone’s liking.
CO2 extraction—or, technically supercritical CO2 extraction—is another way to extract CBD oil from hemp. (“Supercritical” refers to the temperature at which carbon dioxide—CO2—can function as both a gas and a liquid at the same time, roughly 88 degrees F.)
A chamber containing the plant material is filled up with supercritical CO2, and the trichomes and terpenes dissolve into the carbon dioxide. This is one of the few disadvantages of CO2 extraction. Though producing an extremely pure CBD oil, and though theoretically “cleaner” than ethanol extraction (the key word being “theoretically”), CO2 extraction also removes important synergistic nutrients. (That’s why Barlean’s adds additional beta-caryophyllene—a member of the terpenoid family found in the oil of black pepper—to its organic, CO2-extracted CBD oil.)
Supercritical CO2 extraction does not, however, extract chlorophyll, which is why Barlean’s Organic CBD Oil—made with the CO2 extraction method—has a pleasant grassy overtone.
Pros and Cons to Both Methods
Both methods of extraction have their advantages and disadvantages, though these differences become less important when the source plant material is of exceptional quality, and when extraction is done according to best practices. Although solvent residual is always a theoretical possibility, scientists use solvents to extract hundreds of compounds, even ascorbic acid (vitamin C). When done properly, it leaves no appreciable residue.
For those who very much want only organic products, the Barlean’s CO2-extracted Organic Ideal CBD Oil (10 mg per dose) is a great choice. For those who want a higher dose, choose the ethanol-extracted Extra-Strength Ideal CBD Oil (25 mg per dose).
The bottom line is that if you trust the manufacturer, the quality of the source material (hemp), and the integrity of the company producing it, either method of extraction will yield a consistent, safe and effective product.