Hey there, time traveller!
This article was published 31/1/2018 – that’s before recreational cannabis was legal in Canada, so language and information in the article may be dated.
Dear Herb: Is it true that freezing marijuana reduces its potency? — Elsa
Dear Elsa: It sounds like you're facing a classic cannabis conundrum: how to keep your secret stash fresh over the long-term.
On the surface, it makes sense that freezing your weed might actually make it last longer, right? If it works for peas and corn niblets, why not cannabis?
I did some research on your behalf to learn whether it's actually a good idea to freeze your bud.
First, I got in touch with the knowledgeable folks at cannabis testing firm Anandia Labs. Andrew Waye, Anandia's lead scientist for plant analytics, pointed me to a 1973 research paper on this very topic, with the pithy title Constituents of Cannabis sativa L. IV: Stability of Cannabinoids in Stored Plant Material.
The researchers stored cannabis at different temperatures for two years, and found the THC content of cannabis stored at lower temperatures degraded more slowly than the THC content of cannabis stored at higher temperatures.
But Waye pointed out that "light, moisture and air are also very important" when it comes to THC degradation, not just temperature.Advertisement
I next called up Boveda, a company that manufactures humidity control products used for storage of cannabis and cigars, among other things. (They're located in Minnetonka, Minn., so they ought to know a thing or two about freezing.)
"I don't think freezing does anything for cannabis, from what I understand about the process," said Bob Esse, Boveda's vice-president of research.
When you freeze cannabis, said Esse, the trichromes will probably fall off, and you will be more vulnerable to losing them.
What are trichromes? In cannabis, they're the tiny, whitish glands that contain lots of the cannabinoids that produce the drug's psychoactive effects. (When you grind up your weed, broken-off bits of trichromes form the potent, powdery "kief" that gets left behind.)
For personal storage of small amounts of cannabis, Esse recommended an airtight glass mason jar with a moisture control system. Keep the jar in a dark place and the product will be preserved extremely well, he said.
"I don't think freezing does anything for cannabis, from what I understand about the process." - Bob Esse
For the final word, I consulted Robert Connell Clarke's authoritative book Marijuana Botany: An Advanced Study: The Propagation and Breeding of Distinctive Cannabis.
"Cannabis floral clusters are best stored in a cool, dark place," wrote Clarke. "Refrigeration will retard the breakdown of cannabinoids, but freezing has adverse effects. Freezing forces moisture to the surface from the inside of the floral tissues and this may harm the resins secreted on the surface."
Clarke also recommends storing cannabis in air-tight glass jars, rather than the plastic sandwich bags so common in black-market cannabis sales.
So there you have it, Elsa. Keep your treasured cannabis stockpile in an airtight, glass jar in a cool place away from any light, and leave the freezer free for niblets and Hungry-Man frozen dinners.
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