How does extraction work?
Extraction is the gateway step in cannabis processing, transforming raw plant matter into a concentrated crude that can be refined into higher-value products. At its core, the process is about moving cannabinoids and terpenes out of the biomass and into a medium where they can be collected, cleaned, and standardized. How that happens depends on the tools and techniques in play, but every approach shares the same goal: efficiency, selectivity, and consistency.
Solvent-Based Extraction
In commercial labs, solvent systems dominate because of their scalability and control. Hydrocarbons, ethanol, and supercritical CO₂ are the workhorses. Chilled solvent is passed through a packed column of biomass, dissolving cannabinoids and terpenes into what’s known as the miscella. That solution is collected and then routed through recovery equipment, where the solvent is evaporated or distilled away, leaving crude oil behind.
The quality of that crude depends on how the process is tuned:
- Temperature: Lower temperatures suppress the solubility of chlorophyll and waxes, producing cleaner oil.
- Soak time and solvent ratio: Longer contact increases yield but also draws more impurities.
- Solvent composition: Butane-heavy blends maximize cannabinoid recovery; propane-heavy blends preserve delicate terpenes.
Each adjustment trades one benefit for another, which is why dialing in parameters is paramount to striking the right balance for downstream efficiency.
Solventless Extraction
Mechanical methods take a different path. Instead of chemistry, they rely on physical separation: agitation in ice water to release trichomes, pressure and heat to press rosin, chilled tumbling and/or static separation to produce dry sift, or any combination of the above. These techniques are simple, require less infrastructure, and carry marketing appeal as “solventless.” Their limitations are throughput and yield, but for some operators and markets, the trade-off is worthwhile.
Why Extraction Quality Matters
What happens at extraction dictates everything downstream. Clean crude moves faster through filtration, consumes less adsorbent, and allows crystallization and distillation to be more predictable. Poorly tuned extraction, on the other hand, loads the oil with pigments, lipids, and other contaminants that cost time and money to correct later.
For business operators, the takeaway is straightforward: the better the extraction, the cheaper and smoother the rest of the workflow becomes. Mastering extraction is all in execution; the parameters you choose at this stage decide how efficiently the rest of your process will run and how competitive your final product will be.
Why extract at low temperatures?
As mentioned previously, the temperature an extraction is performed at is critical to all downstream processes as a result of its impact on the amount and type of extracted impurities. Running colder reduces the solubility of unwanted compounds such as chlorophyll, plant waxes, pigments, and fats. By limiting how much of these impurities enter the crude concentrate, the extraction produces a cleaner starting material that is easier and less expensive to refine later.
Benefits of Cold Extraction
- Reduced adsorbent use: Since fewer impurities are carried forward, operators spend less on CRC filter media.
- Improved color and clarity: Extracts pulled at subzero temperatures typically show brighter color and better visual appeal.
- Higher terpene retention: By using less adsorbents and reducing the load of other, more difficult to remediate compounds, there is less risk of altering aromatic profiles.
Trade-Offs and Considerations
Working colder comes with its own challenges. Chilling solvents and maintaining subzero conditions requires specialized equipment and higher energy use. Extraction rates are reduce requiring soak periods and require higher ratios of solvent to biomass due to reduced solvency power, which increases energy demand during recovery from both raising the solvent from its subzero temperature and the increased volume. Further, if biomass isn’t properly dried or prepared, ice formation can complicate solvent flow, introduce additional impurities into the solution, and even reduce yields by sealing glandular trichomes behind ice. Operators need to weigh the cost of running cold against the downstream savings in adsorbent use, labor, and product quality; a determination relying heavily upon desired end products.
Why Temperature Matters Downstream
The temperature decision made at the extraction step has ripple effects throughout the purification chain. Cleaner crude shortens filtration times, improves crystallization consistency, and makes distillation more efficient. Conversely, warm extractions that drag chlorophyll and waxes into the crude force additional remediation steps, each one costing time and money.
Looking Ahead
Colder extractions reduce impurities and set the stage for smoother purification. But temperature is only one of several parameters that define extraction performance. Solvent choice, soak time, and ratio also play critical roles — and these parameters, when tuned together, determine just how efficient and cost-effective the entire process will be.
How to prevent yield loss?
Yield loss is the number one concern when running tighter parameters. Increased costs tied to energy requirements and/or reductions in throughput are detrimental to operations, but the real determiner is regularly going to be the overall yield of viable end product.
Crude Yield vs Finished Yield
Emphasis should be placed on the word viable. Products extracted without the correct parameters will show higher crude yields, but those yields aren't necessarily tied to target compounds, and as has been mentioned, excessive impurities in starting crude lead to greater downstream costs. Outputting high quality, high-yielding crude is essential to offsetting increased processing costs by ensuring a greater percentage of your initial crude makes it through to become viable finished yield.
Ways to Increase Yields
Increasing yields when extracting with subzero temperatures comes down to a few methods:
- Soak Time: Increasing soak time gives your solvent additional time to penetrate glandular trichomes and release the mixture of cannabinoids and aromatics contained within.
- Solvent Ratio: As solvent temperature drops an increase in solvent ratio to biomass prevents the oversaturation of solution.
- Solvent Choice: Based on your preferred end product, your choice of solvent can also impact the effectiveness of your extraction.
- Flow Dynamics: Processing techniques can be employed to alter the flow dynamics of the solution during extraction, and when done correctly can lead to a more thorough extraction.
Balancing Yield and Purity
Preventing yield loss is not just about maximizing crude recovery. The goal is to maximize the portion of crude that makes it to finished product. Optimized soak times, solvent ratios, and flow dynamics reduce the risk of leaving target compounds behind, while careful parameter control prevents excess impurities that cut into finished yields.
Even when yields are maximized, crude oil carries residual solids and pigments. The next step, filtration, ensures that the quality of recovered oil is preserved and that more of it survives the downstream purification path.