Traditional cannabutter is made on the stove top with dried flower, but butter can also be infused with marijuana concentrates. Seen here: Packages of shatter concentrate made by using butane hash oil extraction. (Joe Amon, Denver Post file)

Ask The Cannabist: How do I calculate THC for making homemade edibles using BHO?

Hey, Cannabist!
Help! I am looking for a way to use BHO in cooking. I don’t know the ratios. I have made cannabutter many times and made BHO, but I’ve never cooked with it. One ounce of bud to pound of butter and the edibles are good and strong. I have one gram of BHO from the same bud and would love to cook with it. I know it will be so much stronger so I am not sure how to use in a recipe. Your help is appreciated! –Chiefing Chef

Hey, Chiefing Chef!
Yes indeed, it is important to dose homemade edibles accurately! First, let’s cover a couple of points about butane hash oil (BHO), safety and health. Double-check the laws to make sure you are legal to make BHO at home. The Colorado state law (HB 15-1305) that went into effect in July 2015 bans the manufacturing of marijuana concentrates by an unlicensed person using “an inherently hazardous substance” such as flammable butane. Unlawful manufacturing is now a Class 2 drug felony.

In regard to health, there are federal standards in the Occupational Safety and Health Guideline for permissible workplace exposure for n-butane. The recommendation is no more than “800 parts per million as an eight hour time weighted average.”  Although you’re probably not blasting butane for 8 hours at a time, it is important to know how to be safe around this gas. Butane exposure toxicity includes temporary and long-lasting symptoms like hallucinations, irritability, social withdrawal and central nervous system damage, according to the same federal report. Limit your exposure and be smart.

The quality of butane gas used to make BHO is an additional health consideration. Among the Colorado marijuana business regulations, R605 says extraction companies must use solvents that are either food-grade or at least 99 percent pure; the purety of the butane is important because other less-expensive grades can contain contaminants not meant for human consumption.

Additionally, BHO sold in recreational dispensaries is required to pass an analytical test for residual solvents. This standard applies to businesses, but I’m sure you agree it’s important to make clean hash oil that has been fully purged of solvents.

For your dosing guide, I asked Jessica Catalano, Summit County author of “The Ganja Kitchen Revolution,” for her BHO dosing recommendations. She shared her culinary advice via email, and included a few simple and seasonal bonus recipe suggestions.

An important step, decarboxylation, will maximize the THC content of the plant material you use to make concentrated oil. Catalano recommends  baking plant material at 220 degrees for 25 minutes. “Everyone has a different time and temperature for their methods. I prefer that time to preserve terpenes during second processes after the butter is made such as baking,” she says.  BHO can also be decarbed after it has been made by putting the BHO into an oven-safe, parchment paper-lined Pyrex dish and heating it at the same temperature for the same time.

Catalano suggests taking one gram of homemade BHO and adding it to portioned butter. Heat the butter over a low heat and add the BHO by stirring until completely dissolved in the butter.

BHO edibles: How to calculate THC potency
A portion of marijuana concentrate is removed for a dab during the 2014 Cannabis Cup at the Denver Mart. (Seth McConnell, Denver Post file)

Ideally, you already know the THC percentage of the BHO for exact milligram dosage. If you don’t, Catalano says, “Fret not, dry-weight ratios are fine to use as well.”

According to a cannabis equivalency report prepared for the Colorado Department of Revenue, BHO contains 60-95 percent THC. Your one gram of BHO has 1,000mg of dry weight. Therefore, the dry weight ratio would be 600mg THC at the minimum and could be as much as 950mg THC.

A single-serving size for this recipe of BHO-infused butter is a half-teaspoon, which is how we’ll do the first dosage calculation. Let’s break down the math in a couple of examples using one gram of BHO to one cup of butter:

• If your BHO potency is 70 percent THC, one gram contains 700mg THC. With 96 half-teaspoons in one cup of butter, each half-teaspoon serving would have 7.3mg of THC.

• Looking at this another way, if your favorite cookie recipe has a yield of 60 cookies and calls for one cup of butter, you would divide the BHO butter per cookie — if it’s 700mg THC by dry weight, each cookie would have 11.7mg THC.

Remember, the standard THC dose in Colorado recreational edibles is 10mg. If you are inexperienced  or uncertain, it is better to start with a lower dose and wait several hours before consuming more.

BHO edibles: How to calculate THC potency
Marijuana-infused recipes in The Cannabist for appetizers, entrees and desserts. (Bruce Wolf photos, The Cannabist)

If you are a regular edible consumer or dabber and have a high THC tolerance, you can increase the potency per serving by using less butter. If you mix one gram of BHO with 70 percent THC potency into 1/2-cup butter (48 half-teaspoons), each serving has 14.6mg THC.  If the same 70 percent potency BHO is blended into 1/4-cup butter (24 half-teaspoons), each serving would have 29.2mg THC — making an extra-strong dose.

Once you have BHO-infused butter, Catalano suggests a few easy homemade edibles. Make a quick honey spread for two pieces of toast by mixing a half-teaspoon of BHO butter with one tablespoon raw honey and a pinch of cinnamon. In sauce or stew recipes, use one half-teaspoon of BHO butter for each individual serving size. If you feel like baking, here’s an additional step to a baked apple recipe. When baking a large stuffed apple, use one half-teaspoon of BHO butter for each apple. That sounds delicious! XO

Infused recipes: What else do you feel like making? We’ve got the recipes sorted,
appetizers || entrees || desserts

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