For the last few decades concentrated marijuana or hash has been predominantly available through 5 extraction methods. Dry-sift, cold water extraction, CO2 extraction, sound wave extraction, and the most popular today Butane extraction. Recently a well respected Northern California extraction company started using a new solvent for extraction, Propane. Its an interesting solvent that behaves totally different than any of the others currently used. One of the most significant differences is the flavor profile it creates from the extracted terpenes. In this installment of The Week in Weed we return to the interview room with Fresh off the Bud Extractions and learn everything we need to know about this new kind of hash oil known simply as PHO.

Why did you decide to start extracting with propane?
Propane is a light hydrocarbon very similar to butane. Both solvents have very similar polarities and thus produce very similar extracts. We started experimenting with propane extractions when we purchased a closed loop system capable of handling the pressures that propane creates.

Are there advantages to using propane rather than butane?
One advantage to propane over butane is its low boiling point of -43.6 F. This enables us to purge the extract of the solvent very easily, allowing us to produce a solvent free cannabis concentrate.

What else can be used as a solvent?
Virtually anything can be used as a solvent. In fact Water is known as the universal solvent as it is capable of dissolving more substances than any other liquid. Ethanol can be used as a solvent, isopropyl alcohol, heavier hydrocarbons such as pentane and hexane, P.E.T ether, chloroform, DMSO, and the list goes on. Many of these solvents are not acceptable for use in medical products due to their toxicity levels at very small ppm levels. Butane and Propane are great for cannabis extracts due to their non-polar nature and low toxicity levels. The first thing you learn in chemistry is that “like dissolves like” and non-polar solvents like butane and propane dissolve non-polar cannabinoids and terpenoids quite efficiently.

I have heard propane has one less hydrocarbon is that true?
Yes and no. Propane has one less carbon atom but two less hydrogen atoms then butane. The chemical formula for propane is C3H8 while butane is C4H10.

What does that mean?
It means that propane has a slightly different polarity due to the distribution of electrons in the molecule; it is also is the reason that propane has a lower boiling point than n-butane.

Fresh off the Bud process photo

Are hydrocarbons dangerous to consume?
As far as the FDA is concerned butane and propane are generally recognized as safe food ingredients (GRAS). The short answer is yes in low concentrations butane and propane are safe to consume. However, at higher concentrations found in a good amount of extracts today they could be major throat and lung irritants and lead to pulmonary issues. Apart from that their have been no conclusive studies that show butane or propane to be very harmful, especially in cannabis extracts.

What are the drawbacks to using propane?
When using propane it is very difficult to obtain a stable product (shatter). The high terpenoid content of PHO usually causes it to sugar or wax up. Some people prefer this texture, others prefer stable resin.

Why isn’t your whole line PHO?
Our whole line is not PHO because we cater to many different pallets. Some patients prefer a nice sugar or a sap high in terpenoid content and free of residual solvents. Some prefer a nice stable shatter high in cannabinoid content and while low in residual solvent levels <400ppm, is not free of residual solvents.

What determines in your mind what would be a good candidate for propane extraction vs butane? is it based on anything?
This I cannot really divulge as it is becoming a trade secret. Based upon several factors that we have determined the material (either flowers or trimmings) is given a grade and based upon that is processed with a given gas or gas mixture.

Fresh off the Bud hash oil

Visually is there any differences in the final product PHO vs BHO?
PHO tends to look very different than BHO. Occasionally we will have a strain that comes out stable shatter or sap as PHO but that is usually one with less terpenoids or certain strain types. The PHO tends to be a sugar or sap while BHO tends to be a shatter unless either is whipped into a budder. Another difference between the two is the color as PHO tends to have vibrant electric yellow and orange hues rarely found in BHO and a lack of the amber color commonly found in BHO. This is due to the difference in the flavonoid content of the extracts.

Where can California patients find your products?
In Northern California you can find our extracts at Harborside Health Center, Berkeley Patients Group, and San Jose Organics to name a few. You can also stay up to date with all our new drops and new products and new locations throughout the state that our products are available in on Instagram @fobextractions.

Brian Kaiser is Philly, born and raised. After attending Temple University, in 2007 he moved west to Hollywood to open up the Sunset Boulevard dispensary the Alternate Root. After two years of applying his knowledge of all things cannabis to serve his neighborhood in Echo Park, the city forced Brian to shut down his business.

Brian uses his connections to push for cannabis legalization on both a state and national level, a process that begins by just sharing information. We are happy to have Brian as our latest columnist, as he presents the new column This Week in Weed.