Cannabis 101Science & tech

Can Cannabis Oil Go Bad?

Published on July 17, 2017 · Last updated July 28, 2020

Finding a long-lost cannabis concentrate is a bittersweet moment. Your discovered concentrate was left stranded in a pair of jeans that had been stuffed in the far reaches of your dresser, untouched since that last camping trip. For about a year, it’s been sitting in between some parchment paper, waiting for you to unearth it.

The good news: no mold. The bad news: it doesn’t look like the translucent and golden “shatter” you once had. What’s before you now looks like a collection of off-yellow sugar crystals. Has this hash oil gone past its shelf life? Can you still enjoy it?

How long a cannabis concentrate lasts depends on a number of factors ranging from the quality and classification of the starting material used to the packaging and storage of the final product. While some extracts and infusions can experience quality degradation in a very short time span, others may stay fresh and useable indefinitely.

The Impact of Extraction Method on Concentrates

The Impact of Extraction Method on Concentrates

(Julia Sumpter/Leafly)

Over time, some shatters will sometimes “sugar out” as their terpenes degrade away, leaving a substance with a higher concentration of THCA behind.

The golden standard in any extraction methodology is that the quality of the end product will always reflect the quality of the starting material. “Gold in, gold out; Garbage in, garbage out.” There’s a direct correlation between the quality of the starting material and what remains post-extraction. Inferior products containing compromised cannabinoid profiles will, in every case, result in an inferior extract.

Terpenes will almost always experience degradation of some kind during extraction. The loss will not only affect the flavor and medical efficacy of the final product, it could play a role in that product’s shelf life as well. Some products, such as those purposed for dabbing, utilize extraction methods intended for terpene preservation. Extractions meant for infusions such as for edibles, topicals, and tinctures  however, may not necessarily need to utilize these terpene preservation methods.

Concentrates come in a variety of forms, ranging from extracts like saps, shatters, crumbles, butters, and distillates to sifted mechanical varieties like kief, ice water extract (IWE), and dry sift. Their attributes, such as consistency, viscosity, and clarity, are all byproducts of their extraction method.

The basic principle of an extraction is to remove the many impurities from the starting material, which include plant matter, fats and lipids, and other foreign contaminants. Many fats and lipids in solventless concentrates remain because they are more difficult to mechanically remove.

Solvent extractions, on the other hand, produce “oleoresins” that contain a combination of cannabinoids, flavonoids, and terpenes, as well as other impurities such as fats and lipids, in many cases. Through a secondary solvent filtration process called “winterization,” these fats and lipids may be removed from a product, leaving behind a more purified substance.

The process of winterization is known to cause some terpene degradation that could compromise both the flavor profile and the consistency of the final product. However, this process is necessary for the production of super stable hash oil products such as glass-like “shatters,” as well as high terpene-containing saps and sugars.

Terpenes, Cannabinoids, and Concentrate Shelf Life

Terpenes, Cannabinoids, and Concentrate Shelf Life

(Julia Sumpter/Leafly)

The greatest perceived enemies of any concentrate, be it a wax, shatter, sap, or any cannabis oil-infused product, are all the same: light, heat, air, and time.

Concentrate varieties range in consistency from stable shatters and viscous saps to butters and sugary waxes. Each variety contains a different combination of molecules (e.g. cannabinoids, terpenes, lipids , impurities), but most carry a high concentration of the cannabinoid tetrahydracannabinolic acid (THCA).

The geometric structure of pure THCA is comprised of lattices stacked onto one another, forming a crystalline structure. However, THCA in a concentrate mixture will crystallize differently, depending on variables such as the ratio of other impurities present to agitation and temperature.

Related
What is THCA and what are the benefits of this cannabinoid?

For instance, “shatters,” known for their super stable glass-like consistency, are typically monocrystalline in final form, meaning they exhibit many properties consistent with amorphous solids (they have softer melting point ranges and appear less rigid in molecular structure) when exposed to varying concentrations of terpenes, impurities, or even other cannabinoids like CBD.

Shop highly rated stores near you

Showing you stores near
See all stores

In order for shatter to maintain a glass-like physical structure, it must go through further filtration to remove these impurities. If left in a product, these other components can do many things, one of which is to cause a “buttering” effect in a concentrate when agitated or brought to varying temperatures.

Related
Why Low Temperatures Are So Important for Dabbing

When terpenes or even other cannabinoids such as CBD are present in a concentrate, they can also act as emulsifiers (a mixing or solvating agent) to the crystalline THCA. A concentrate that is richly saturated in both THCA and in terpenes can take on different consistencies depending on how the product was agitated and at what temperatures that product was exposed to. These varying phases that concentrates exhibit (e.g. polycrystilline to amorphous) are largely influenced by the many impurities that prevent THCA from crystallizing.

Impurities can include anything from elevated levels of terpenes to fats, lipids, solvents, as well as the presence of other cannabinoids. For example, concentrates high in cannabidiol (CBD) will appear sappier due to the distinct structure of its molecule.

Related
How to measure THC & CBD content in weed

Over time, some shatters will sometimes “sugar out” as their terpenes degrade away, leaving a substance with a higher concentration of THCA behind. Although this process may compromise the experience a hash oil product may have once given, it’s not a final indicator that the product is unable to be used for vaporization (dabbing). Rather, it simply means that the molecular structure of the oil has changed as a result of the terpenes degrading out of the concentrate.

“Sugary”-like hash oils that were once “shatter”-like in consistency is our visual observation of what happens during terpene degradation, when THCA no longer has to worry about terpenes getting in the way of crystallization.

Related
Infographic: How Do Cannabis Terpenes Affect the Body?

Cool, dark, dry, still environments (refrigerators, freezers, low cabinets, freeze driers) are best for promoting longevity of your cannabis concentrates.

The greatest perceived enemies of any concentrate, be it a wax, shatter, sap, or any cannabis oil-infused product, are all the same: light, heat, air, and time. All of these elements facilitate the degradation of terpenes and cannabinoids, and will hasten the process by which some of your concentrates and infusions change.

Cool, dark, dry, still environments are best for promoting longevity, and when exposed to as few environmental contaminants as possible, some of these products will last a very long time without changing or losing anything.

Optimal storage options include refrigerators or freezers, low cabinets, or a freeze drier. These will help to eliminate the variables that tend to break down extracts. Over time, the cannabinoids (and, in some cases, terpenes) will inevitably change in some ways, regardless of condition. THCA will eventually degrade to cannabinol (CBN), a process which creates an “amber-ing” or darkening effect. Shatters and other dabble oils with higher terpene profiles may also sugar up, just like the one you found in your dresser.

Related
How to Store Cannabis Oil, Tinctures, and Other Products

At the end of the day, that sugary shatter isn’t going to be a deal breaker. While your concentrate may not taste quite the same or give you that “full spectrum” feeling, a nice dab will still do the trick as those THCA crystals will still pack a punch.

Shop highly rated stores near you

Showing you stores near
See all stores
Patrick Bennett
Patrick Bennett
Patrick lives with his wife and daughter in Denver, where he spends his time writing, photographing, and creating content for the cannabis community.
View Patrick Bennett's articles
Get good reads, local deals, and strain spotlights delivered right to your inbox.

By providing us with your email address, you agree to Leafly's Terms of Service and Privacy Policy.



Stay In Touch

Receive updates on new products, special offers, and industry news.

By providing us with your email address, you agree to Leafly's Terms of Service and Privacy Policy.

Leafly mobile app
Get high for less.
Download the Leafly app.
Download Leafly: Marijuana Reviews on the App Store
Download Leafly Marijuana Reviews on Google Play




The material provided on Leafly is intended for educational and informational purposes only. Leafly is not engaged in rendering medical service or advice and the information provided is not a substitute for a professional medical opinion. If you have a medical problem, please contact a qualified health professional.


© 2024 Leafly, LLC
Leafly and the Leafly logo are registered trademarks of Leafly, LLC. All Rights Reserved.