How is CBG oil made? The CBG extraction process

The CBG extraction process takes the cannabinoids out of dried hemp with a solvent, usually supercritical CO₂ or ethanol, then refines the extract and dilutes it in a carrier oil. Because ordinary hemp contains less than 1% CBG, producers start from varieties bred for CBG. Heat during processing turns the plant's CBGA into CBG, and the finished oil is tested for its cannabinoid content.

What is the CBG extraction process, step by step?

1. Choosing the plants. CBG oil starts with hemp that contains a lot of CBGA. Varieties with the B0 genotype convert little of their CBGA into other cannabinoids, so CBG becomes their main one (Zagožen et al., 2021).
2. Drying and grinding. The harvested flowers are dried and ground so the solvent can reach the resin.
3. Extraction. A solvent, usually supercritical CO₂ or ethanol, dissolves the cannabinoids and terpenes out of the plant material (Nahar et al., 2021).
4. Refining. The crude extract still holds plant waxes, fats and chlorophyll. These are removed, and the extract can be concentrated further.
5. Decarboxylation. Heat removes the acid group from CBGA, which turns it into CBG (Wang et al., 2016).
6. Dilution. The concentrate is mixed with a carrier oil to reach the strength on the label.
7. Testing. A laboratory measures the cannabinoids in the batch, and the results go on a certificate of analysis.

Where does CBG come from in the hemp plant?

Hemp makes its cannabinoids as acids, and cannabigerolic acid (CBGA) comes first. Plant enzymes turn most of it into the acid forms of THC, CBD and CBC, and CBG forms when CBGA loses its acid group (Jastrząb et al., 2022). That is why mature hemp usually holds less than 1% CBG (Perez et al., 2022) and why CBG is called the "mother cannabinoid". For the molecule itself, see our guide what is CBG (cannabigerol)?

CBG can also be made without the plant. Perez et al. (2022) tested CBG produced by yeast fermentation, a method developed because extracting minor cannabinoids from hemp is costly.

CO₂ or ethanol: which CBG extraction method is better?

Both solvents are standard in the industry, and each has trade-offs. Solvent extraction with organic solvents such as ethanol is the most common method for cannabis (Lazarjani et al., 2021). Supercritical CO₂ is valued because it is selective, and because the CO₂ returns to a gas when the pressure drops, leaving an extract without solvent (Qamar et al., 2021).

How do you make CBG oil from the extract?

A refined extract can be used in two forms. A distillate keeps CBG together with other cannabinoids from the plant. An isolate is CBG purified on its own, usually by chromatography and crystallisation. Full-spectrum and broad-spectrum oils are made from extracts or distillates, and CBG isolate oils from the purified compound. The differences are explained in full spectrum vs broad spectrum vs isolate.

The concentrate is then mixed with a carrier oil, such as MCT oil or hemp seed oil, until it reaches the strength on the label. The CBG content per drop depends on that dilution. To check what a bottle contains, read its certificate of analysis; our guide how to read a certificate of analysis shows what to look for.

How is the CBG oil at Formula Swiss made?

We extract with CO₂ only. Our hemp is grown in Central Switzerland following organic principles. Lugano Clarity is our CBG-richest oil, with 10% CBD and 7% CBG in MCT oil and a 0% THC specification. CBG is also part of the cannabinoid profile of Lucerne Calm, Zermatt Balance and St. Moritz Restore; the CBG vs CBD comparison lists the measured values. All our oils are in the CBD oil collection.