An often overlooked aspect of the Cannabis industry is the storage of the plant in its different presentations. There is scarce information regarding the role of proper storage and its effects on the Cannabis metagenome (genetic content). This has led to the contamination of several Cannabis-based products used for the commercial, industrial, and even medicinal sectors.
The appearance of mycotoxins, fungi, and other microbiological pathogens has led to not only hazardous risk effects in Cannabis healthy and unhealthy consumers but also to sudden deaths due to unpurified products. Therefore, it is imperative to develop adequate techniques for Cannabis-based products.
It is crucial to have a suitable long-term storage methodology to preserve the constituents of a Cannabis-based product. This is vital from a research to a commercial standpoint given that various Cannabis compounds undergo oxidation and degradation which affect their final abundance and concentration.
What are the best conditions to store your Cannabis products?
A study led by the Swedish National Forensic Centre in Switzerland periodically measured for 48 months the abundance of several compounds of Cannabis on different storage conditions to aid with the identification of the most stable compounds and use them as profiling markers in Cannabis resin.
Herein, they found that CBD was the most stable marker for accurate Cannabis resin profiling since it was not subjected to change independently of the storage condition. Further results are portrayed below.
| Compound abundance increment | Compound abundance decrement | Unchanged compound abundance | |
| No air exposure at -20˚C | ∆8-isotetrahydrocannabinol | – | ∆9-THC, CBN, CBD |
| Air exposure at room temperature | CBN, caryophyllene oxide, caryophylla-3,8(13)-dien-5α-ol, clovanediol, n-nonacosane | isocaryophyllene, ∆9-THC, β-caryophyllene, α-bergamotene, α- and β-humulene, ∆1-tetrahydrocannabiorcol, THCV | CBDV, CBL, n-hentriacontane, CBD |
| No air exposure at room temperature | – | ∆9-THC | CBD |
On the other hand, a study led by the University of Lethbridge in Canada sought to optimize a long-term storage method for Cannabis pollen through cryopreservation.
They found that Cannabis pollen dried with vacuum desiccation at a pressure of 5 kPa later combined with baked wheat flour (known to act as a cryoprotectant) and followed by liquid nitrogen storage was effective to preserve the germination capabilities of the pollen.
They validated their results by performing a pollen germination assay and concluded that they were able to store the pollen through their method for 4 months without affecting their pollen germination efficiency when compared to 24-hour storage in liquid nitrogen.
What should businesses know about their Cannabis product storage?
Nowadays, Cannabis product storage remains an underdeveloped aspect of the Cannabis industry. Improper storage can lead to an undesired final product which could affect the health of the consumers.
It is key to implement the appropriate techniques to identify in which stages of Cannabis farming (growing, harvesting, curing, storage, etc.) the plant is more subjected to biochemical changes and contamination.
Close attention must be given to the storage temperature since most of the concentration of the compounds is subject to change when the post-harvest flower and the pollen were stored at non-freezing temperatures.
Finally, other variables such as air exposure and light need to be taken into account for the long-term storage of Cannabis-based products. In the future, well-suited protocols will aid with the consolidation of the Cannabis industry globally and prevent avoidable casualties.
Gaudet, D., Yadav, N. S., Sorokin, A., Bilichak, A., & Kovalchuk, I. (2020). Development and optimization of a germination assay and long-term storage for cannabis sativa pollen. Plants, 9(5). https://doi.org/10.3390/plants9050665
Grafström, K., Andersson, K., Pettersson, N., Dalgaard, J., & Dunne, S. J. (2019). Effects of long term storage on secondary metabolite profiles of cannabis resin. Forensic Science International, 301, 331–340. https://doi.org/10.1016/j.forsciint.2019.05.035
Vujanovic, V., Korber, D. R., Vujanovic, S., Vujanovic, J., & Jabaji, S. (2020, February 1). Scientific prospects for cannabis-microbiome research to ensure quality and safety of products. Microorganisms. MDPI AG. https://doi.org/10.3390/microorganisms8020290
