Every agricultural product is characterized by its shelf-life, which represents the time during which the quality remains intact. After this threshold, a given product starts deteriorating, resulting in a number of consequences. When it comes to cannabis, however, there isn’t still a commonly accepted notion of what the shelf life of a dried flower is. The question of the shelf life of dried flowers became particularly important as the industry got regulated because each producer is required to have their flower tested before they can hit the market. Knowing how long a specific product would last is important for branding, but also to further understand how shelf-life can be pushed without affecting the overall quality.
A recent study authored by Juris Meija, Garnet McRae, Christopher O. Miles, and Jeremy E. Melanson published in Analytical and Bioanalytical Chemistry, focuses on the effect of temperature on the degradation of cannabinoids in dried flowers. Even though there have been studies exploring the degradation of cannabis flowers, they inevitably fell short on one premise: “Many studies devoted to measurements of cannabinoids do not distinguish between the carboxylic cannabinoids and their decarboxylated analogs,” the authors say. The main issue lies in the fact that previous methodologies proved to be either unreliable or provided biased results.
Thus, the authors conducted high-precision measurements of seven pairs of cannabinoids of dry cannabis at storage conditions near room temperature. The material was separated and placed in different temperature conditions that ranged from -20 degrees Celsius to 40 degrees Celsius for up to one year. On a regular basis, the authors have examined the degradation of cannabinoids over time.
The authors conclude: “A simple first-order kinetic model is able to explain the changes of both major and minor cannabinoids under a variety of storage conditions up to +40 ◦C.” A first-order reaction refers to those reactions that develop at a rate that depends on the concentration of one reactant only. Bluntly put, for cannabis, is possible to use parameters of THCA and THC to examine the decarboxylation concerning time and temperature. Of course, there might be some differences about specific cultivars. That’s why authors acknowledge that further studies to assess that are necessary. At the same time, they claim: “The results from our study could help inform cannabis regulators in setting degradation thresholds or shelf-lives, and could lay the framework for standardization of stability testing in the cannabis industry.”