Contributed by John Darius Soltes, CHMM
Everybody has heard of delta-9-tetrahydrocannabinol, commonly known as THC- it's what gets you high. But did you know that most of the THC in harvested flower is in the form of THC-Acid (AKA Tetrahydrocannabinolic acid)? In fact, bud with a 22% total cannabinoid concentration may contain up to 19% THCA. THCA does not interact with the cannabinoid receptors of the brain and therefore does not contribute to the psychoactive effect of marijuana. When smoked, THCA is spontaneously converted to THC. However, when using untreated flower for cooking or oil infusion the situation is not so "cut and dry."
See the difference? A black ball (carbon) and 2 red balls (oxygen) were removed from the right-most ring structure. And just like that, THC has been created!
Let’s Get Cooking with LEVO
In a recent study performed by yours truly using LEVO, 2 grams of flower and Grapeseed Oil showed that THCA was indeed infused into the oil. The LEVO unit allows for constant temperature settings between 90F and 200F and infusion times up to 10 hours. I ran this test twice, once at 95F and once at 200F. The oil was sampled at 1.5 hours, 5 hours, and 9 hours for both temperature settings and submitted to a local laboratory. When the flower was infused at 95F the THCA concentrations increased over time. When the flower was infused at 200F THCA actually decreased. So what was happening? Well, 200F was hot enough to decarboxylate some of the THCA, converting it to THC.
How does this factor in with recipes? Say for example you want to make a medicated hummus or salad dressing. If you use a LEVO infused oil that has been prepared at 95F none of the THCA will be converted to THC during the food preparation - this is because these recipes typically do not call for heating the ingredients. If, on the other hand, you were to use a LEVO infused oil that has been prepared at 200F there will be more THC and therefore more of a psychoactive effect. All of this is based on personal preference. Maybe you don't want to get blasted off of your infused vinaigrette, (then again maybe you do). The choice is yours.
Although THCA won't get you high- it has been shown to have anti-inflammatory properties.1The anti-inflammatory effect centers around the interaction of THCA with an enzyme in the body called cyclooxygenase (COX). A study conducted in 2011 showed that THCA (along with CBDA, CBGA, and CGB) inhibited COX in a similar way as aspirin. The anti-inflammatory effects increased with concentration of cannabinoids ingested. This study also showed that THC and CBD had low COX inhibiting effect compared to the other cannabinoids mentioned earlier.
Here is a tip if you are trying to maximize THC but will only be using low temperatures for your recipe. Pre-treat your bud!
- Place your flower or trim in an oven safe pyrex or ceramic baking dish.
- Preheat oven to 240F
- Cover with tin foil and place in oven for 60 minutes.
Voilà! Your THCA in the flower has been fully decarboxylated. *Warning -it should be noted that this will dry out your ingredient and you may also lose some of the volatile terpenes.
More bang for your buck - HOT HOT HOT!
Up for a sauté? Cakes, brownies, "pot" pies? - YES PLEASE!
Cooking temperatures vary based on your own personal style; I go for a low and slow approach (it usually takes me 2-3 hours to caramelize a bag of onions when I make french onion soup). But a temperature range from 280F to 330F would be typical. For more information check out this wikipedia link.
For those nit-picky nerds out there - here is a chart that illustrates THC concentration at various temperatures with time. (Courtesy of skunk pharm research2)
As this chart shows, any temperature above 200F will start the THCA to THC conversion reaction. Remember the LEVO at 200F? Although this is on the low end of the temperature needed for decarboxylation, the oil was infused for a total of 9 hours and thus it yielded similar results. At the highest temperature range (300F), and given enough time THC starts to decrease as it begins to turn into Cannabinol (CBN)3, which can promote drowsiness (but we'll save that conversation for another time).
For baked goods, factor in the final internal temperature. Brownies and cheesecake will be at around 165F (the minimal food safety temperature) while breads may heat up to 210F. It should be noted that the internal temperature of baked goods will increase over time. Once the final temperature is reached and the food is removed from the oven, the THCA to THC process will cease as the food comes to room temperature.
I hope you have enjoyed reading this blog as much as I enjoyed writing it. Thank you for allowing me to share my thoughts on this topic and...Bon Appétit !
About the Author:
John Darius Soltes is a professional chemist with over 15 years of experience in both environmental science and analytical laboratory chemistry. Over the past year he has focused his attention on cannabis extracts and terpene chemistry and currently works in the Denver metropolitan area.