Attributing variance: Harvest size, sample size, and test size
In a recent blog post, we mentioned a few of the many factors that can contribute to variance in test results and variance between the product tested and the product that ultimately reaches consumers. Among those factors is the size of the harvest, how much we sample from that harvest, and how much actually ends up being processed by our team and equipment in the lab.
As our cannabis grower friends know, the OLCC requires that harvests be inventoried in 50-pound batches, and that a minimum of 0.5% must be sampled for testing. Some basic math here — 50 pounds is just shy of 22,680 grams (22,679.62 to be exact), meaning 0.5% is equal to 113.4 grams. We collect an even 114 grams, pulling flower from different levels of the inventory bin for a diversified sample, and leaving the grower with as much product as possible to bring to market.
The next step in the process is homogenization, when all of the flower is ground up to create a uniform blend — more on the homogenization process in a future post. It’s from this aggregate that we take just six grams in a small vial to use for testing potency.
More simple math — those six grams are a little more than 5% of the total sample and just a tiny fraction of the harvest batch at only 0.026%. That is a small number. The good thing is that both the sampling and homogenization processes lead to test results that represent an average of the batch as a whole. But of course not all nugs are created equal, so what ends up in one dispensary or consumer’s hands could still be significantly different from the results or from the same product somewhere else.
And as we’ve mentioned before, there are many other factors that could lead to differences in product past the point of testing, like storage and exposure to air, light, and moisture. We’d like to keep digging into topics like these, and we’d love to hear what you’re most interested in! Please reach out and let us know!