Cannabis producers spend months caring for their crops, battling against pests, disease, and harsh climate to produce plants with bountiful buds and a high trichome density. Come harvest time, the peak trichome maturity is captured and preserved through fresh frozen cannabis or refined through a drying and curing process.
Cannabis processing can convert fresh frozen or dried plant material into various infused products, but can also end up destroying a lot of these valuable cannabinoids and terpenes when done improperly. Here, we show you where processors can go wrong and how they can preserve the most cannabinoids and terpenes from their oil.
Maximizing Cannabis Extraction Yield
A major aspect of getting the most out of your Cannabis biomass includes extracting as many cannabinoids as possible. Processors usually measure yield by comparing the weight of the extract produced with the weight of the biomass used. Other factors that affect the extraction efficiency include the overall biomass potency, biomass consistency, extraction run time, solvent used, and solvent temperatures, among other factors.
Cannabinoid loss, in particular, affects the bottom line more significantly than losing terpenes, for example, because most consumers value the cannabinoid potency of a product over just about any other factor when buying cannabis. In addition, terpene content is not usually listed on cannabis products. Although the tides are shifting favoring whole-plant extract, cannabinoid extraction efficiency should be top of mind for all processors.
During cannabis extraction, there are many areas where cannabinoids can be lost, from loading the biomass material into the material tank to collecting the extracted oil. Optimizing every step of the extraction process is the only way to ensure that the least amount of cannabinoids are lost to the process.
Who Is Affected by Cannabinoid Loss During Processing?
Cannabinoid loss during extraction or even before or after the process affects everyone in the supply chain, including customers. Cannabis growers can lose out on profit if the biomass is improperly handled or stored, whether it’s from breaking off the fragile trichomes from mishandling or evaporating low-boiling-point terpenes during drying.
Cannabis processors can also lose out on revenue if they are not able to reap the most amount of cannabinoids possible. Cannabinoids that are not extracted properly or are lost during the process is money down the drain. Not only do processors lose revenue, but they also develop a less-than-ideal reputation among dispensaries and customers. In today’s cannabis markets, high potency is still one of the major factors consumers consider.
Cannabis consumers are the last ones to experience the effects of cannabinoid loss. By the time someone buys a product, the cannabinoid potency is at its comparatively lowest level, providing less bang for their buck, weaker potency, and reduced effects. Although customers can check the potency levels before buying, they do not know how much was wasted in the extraction process.
What Causes Cannabinoid Degradation During Processing?
Cannabinoids are destroyed or degraded throughout the supply chain, including during the processing and post-processing phase. Various factors can affect the cannabinoid extraction yield, especially not when extraction technicians do not follow the proper standard operating procedures or when faulty equipment is used.
In order to understand how cannabinoids are lost during cannabis extraction, it’s important to know how cannabinoids degrade throughout their various stages of life due to the ambient environment. Here are the main factors that influence cannabinoid degradation, which usually occur before processing.
Prolonged exposure to natural sunlight and artificial grow lights can hasten THC degradation. To preserve the plant’s trichome quality, producers store cannabis flower away from light in a dark space. An opaque container is the container of choice for cannabis consumers who want to preserve their product’s potency, flavor, and aroma and prevent light exposure.
High temperatures can negatively affect the THC content of a product. Hot temperatures can increase the risk of mold growth and degradation due to decarboxylation from the heat. Monoterpenes especially are vulnerable to evaporation at lower heat temperatures.
Moisture is one of the worst culprits of cannabinoid or complete product loss. High relative humidity concentrations can increase the risk of mold, which is unsafe to consume and can cause products to fail third-party testing. Excessively low humidity levels can dry out the material, removing terpenes, which can affect how cannabinoids interact with the body.
Keeping cannabis out in the open air can significantly reduce cannabinoids. High levels of oxygen can cause cannabinoids to degrade much quicker than in an environment with reduced oxygen levels. When exposed to air, THC can degrade to cannabinol (CBN) much quicker, which doesn’t have the same psychoactive effect.
After harvesting cannabis, producers still face the threat of cannabinoid loss from every angle. In the climate-controlled drying room, various factors such as humidity, temperature, and airflow can significantly affect the quality of the dried material. A suboptimal environment can cause complete crop losses in some cases.
During the drying process, excess moisture in the cannabis plant is removed. The total moisture weight loss depends on many environmental factors. Cannabinoid loss can be prevented well before it’s time for extraction by creating an optimal drying room environment. Here are a few tips to consider in the drying room to prevent major potency losses:
- Relative humidity (RH) measures the water vapor in the air. Ideal drying room levels should be around 55%, with lower relative humidity as temperatures cool, but never falling below 50%. A hygrometer can help producers keep track of the RH.
- High-pressure sodium (HPS) lighting produces more heat and takes up more energy than energy-efficient light-emitting diode (LED) lighting. LED lights are known for running cooler. A climate control system can monitor and control temperature levels to prevent fluctuations.
- Drying rooms should be able to handle the amount of plants being dried and have enough space between material for proper airflow and mold prevention. Wet trimming removes the fan and sugar leaves before drying, giving buds more space and airflow to dry.
It all starts with the right cannabis flower strains, which can vary depending on a processor’s desired end products and extraction methods. For the highest yield possible, processors should start with material that has a high THC level with a high concentration of resin on the biomass. Starting with resin-rich biomass is the best way to reap high cannabinoid levels.
In addition, the amount of starting plant material used during extraction is a defining factor in the overall cannabinoid extraction and loss. Of course, the more starting material you have, the more cannabinoids you can extract from the plant. A smaller amount of biomass will generally yield lower losses.
Stored Plant Material
After harvesting the crop, proper storage of the cannabis biomass for processing can preserve more of the cannabinoids and terpenes. Storing biomass in an environment with high humidity and temperatures can speed up degradation and cause significant cannabinoid losses. Leaving biomass sitting for too long without processing can also reduce overall freshness and potency.
Cannabis extracts stored at a processing facility or dispensary can experience noticeable cannabinoid loss. For dispensaries, this can be a challenging aspect because they have to properly store the product and may cut prices to ensure that the product is sold before it “expires.”
Dispensaries tackle the cannabinoid loss issue by freezing cannabis concentrates in their back room and refrigerating concentrates that are on the sales floor. Without the right cold storage after the cannabis extract has been produced, it can suffer from major cannabinoid losses. One problem with the freezer could spell disaster in revenue.
Recommend storing as cold as possible for all extracts to avoid degradation and terpene loss. Preferably below freezing
Vacuum sealing is a good way to prevent cannabinoid loss when storing fresh frozen cannabis. Vacuum sealing units remove air from the container, providing the material with storage that reduces cannabinoid degradation and oxidation. However, removing too much air can cause the material to compress and destroy trichomes. Instead, processors should leave enough air in the vacuum sealed container to provide a cushion between stored bags.
Cannabis processors can use a variety of biomass quality, ranging from low-grade trim to high-grade cannabis flowers. Milling cannabis is necessary in some cases to increase the surface area of the biomass and improve the extraction efficiency. Generally, small particle sizes are associated with high recovery of cannabinoids and terpenes.
Cannabis material that is too finely milled can have a larger surface area and allow solvents to dissolve more compounds. However, finely milled cannabis can have more chlorophyll, requiring more post-processing to remove it.
Cannabinoid loss can occur throughout the processing phase, especially if the material is too fine. Solvent channeling is an issue that causes some solvents to move around the biomass instead of through it. This can occur if the material is too fine, too big, or has been packed unevenly.
The ideal particle size can vary depending on the extraction method. For example, ethanol allows for a fast extraction with a high efficiency of 95% or higher cannabinoids. Using cold ethanol and large particle sizes reduces the extraction of chlorophyll and reduces the need for post-processing to remove these pigments.
Hydrocarbon solvents are able to efficiently extract cannabinoids from a wide range of biomass materials. Grinding cannabis biomass is not needed before hydrocarbon extraction but can increase the process’ efficiency. Grinding biomass when using hydrocarbons can dissolve unwanted compounds such as chlorophyll and waxes, requiring more processing to remove them.
CO2 extraction is not as efficient as hydrocarbon or ethanol extraction. Grinding the material increases the surface area and allows processors to more evenly pack the material tank, which can improve the extraction efficiency of CO2.
Cannabis extraction methods include solventless and solvent-based techniques. Within these extraction methods there can be many variables that affect the extract potency yield, including equipment capacity and extraction efficiency, solvent quality, automation, operating temperatures and pressures, and many more factors.
Supercritical carbon dioxide (CO2), ethanol, and hydrocarbon extraction are the most common types of solvent-based extractions. Solvents have a higher efficiency of extraction and faster run times than solventless extractions such as rosin pressing, dry sifting, or ice water hash making. With each method, however, there is a lot of room for error.
Hydrocarbon extraction is the best processing method for capturing as many cannabinoids as possible without experiencing significant cannabinoid losses. Hydrocarbons are especially helpful when doing full nug runs, which maintain the quality of the bud while allowing the hydrocarbons to penetrate the biomass and dissolve the cannabinoids.
Movement of Cannabis Plant Material
Cannabinoid loss can occur when moving the material from one part of the extraction workflow to another. When handling the material, especially in a rough manner, the biomass can lose trichomes, and, thereby, lose cannabinoids and terpenes. In addition, manually transferring biomass from one equipment to another can take up a lot of time that adds up over time.
When transferring sticky cannabis oil from one container to another, there can be product loss if any is left behind in the extraction vessel. A scraper or similar tool reduces the amount of transfer loss after the extraction run. Since this can be a manual task, the product yield can also depend on the extraction technician’s skill. Automated systems can reduce the handling of biomass from loading to collection of the refined extract.
Solvent temperatures in the extraction process can significantly affect the yield. Generally, colder operating temperatures are slower at dissolving cannabinoids than hotter temperatures. However, cold cannabis extraction techniques allow processors to preserve more of the volatile desirable compounds, such as terpenes, which can degrade when exposed to high temperatures for extended periods of time.
In large-scale ethanol extraction, pre-chilling the solvent as low as -40º F can reduce the need for post-extraction processing, which can result in cannabinoid losses. Pre-chilled solvent can improve the extraction efficiency and reduce cannabinoid loss.
Solvent Flow Rate
Solvent flow rate is the mass of the solvent that is pumped through the material tank during a run. Solvent flow rate can be quantified as grams or kilograms per minute, depending on the system’s capacity. In some systems, an in-line mass flow meter can allow extraction technicians monitor for any inconsistencies in the flow rate.
Modern extraction systems aim to handle a high flow rate to reduce extraction run times. However, very fast or slow flow rates can reduce cannabinoid extraction efficiency. At fast flow rates, the solvent moves through the material tank at high velocities. At this flow rate, the solvent is not able to properly diffuse through the biomass. The solvent needs to be able to permeate through the biomass and properly dissolve the trichomes.
In fast flow rates, the solvent passes through without having enough contact time with the biomass, which is needed to dissolve the desired compounds. The optimal flow rate varies by extraction system and biomass quality. Processors should determine the right flow rate for the desired end product with a few runs before going all in.
Decarboxylation is an essential process that converts carboxylated cannabinoids into their active forms. During the process, the carboxyl group is removed from a specific compound, typically using heat. In cannabis, this generally means converting delta-9 tetrahydrocannabinolic acid (THCA) into delta-9 tetrahydrocannabinol (THC).
Cannabis can be decarboxylated in an oven as cannabis buds or before the distillation process as a crude oil. After the extraction process, decarboxylation is performed by applying heat, agitation, and vacuum to the crude extract. Processors that use low-quality vessels for decarboxylation can increase the risk of overheating the biomass, potentially degrading desired compounds or completely destroying them.
For processors, finding the optimal temperatures for the conversion of inactive compounds to active ones is crucial to maximizing yield and reducing cannabinoid loss. However, each cannabinoid has a different boiling point, so extraction technicians must target one or a group of cannabinoids that have similar optimal decarb temperatures.
Winterization is a refining process that removes lipids, fats, and waxes from crude extract. Crude oil is mixed with ethanol and frozen, allowing the unwanted compounds to solidify. This allows processors to easily filter and separate the fats, lipids, and waxes from the refined oil. Winterization is not necessary in certain processing methods that use cold temperatures.
Although winterization can help remove these stubborn compounds, it can also strip valuable cannabinoids. Some processors have seen 5-10% cannabinoid loss after performing winterization. Choosing the right extraction equipment and processes can reduce the need for removal of the undesirables in the first place and achieve recovery rates of 90% and above.
Color remediation is a processing technique used to remove the undesirable compounds such as chlorophyll, waxes, fats, and other particles, from crude extract in a color remediation column (CRC). Removing the pigments can not only improve the color and clarity of the oil, but also its flavor and aroma.
CRCs can contain various filtration media packed in layers, including activated charcoal, diatomaceous earth, activated bentonite clay, and activated silica gel. These adsorbents act as a stationary phase where pigments are electrically attracted to the filter media. Undersaturating the extract can cause cannabinoids to be left behind.
Some processors have seen cannabinoid retention from using activated carbon to remove color. The active carbon itself does not seem to be the cause of the cannabinoid retention. Yield loss can be attributed to a large amount of hold-up volume in the system after the filtration.
Hold-up volume is the leftover liquid that remains in the media or equipment after the filtration run and can be offset by flushing the system with clean solvent. In addition, processors should have enough drain ports to remove all of the liquid inside.
Distilling cannabis can produce some of the highest potency products on the market, with THC levels reaching 90% and above. However, some distillation methods can reduce THC content. Distillation works by heating the extract to a certain temperature and collecting the desired compounds through cooling and condensing them into a liquid.
Cannabis oil is distilled at high temperatures, usually in a vacuum to lower the boiling point of the desired cannabinoid. During this process, THC levels can undergo a complex degradation process, which can produce CBN. Before it reaches this stage, THC can degrade into dihydroxy-THC, where a hydroxyl group is added.
Under poor operating procedures, the distillate produced can have up to 20% of degraded forms of THC. Since dihydroxy-THC is non-psychoactive, consumers are getting less THC than what they expected. In some cases, the smell and taste of these degraded components can produce a burned flavor.
Processors can employ various strategies to reduce the degradation of cannabinoids. Heating the extract at the right temperature in an even manner can ensure no one part of the extract is heated too much. Vacuum leaks in the distillation process can also affect cannabinoid loss.
Emulsification is a process that turns cannabinoid oils into water-soluble emulsions, commonly found in cannabis beverages. During the process, the cannabinoids are reduced to smaller droplets. An emulsifier is used to keep the droplets dispersed throughout the liquid instead of coming back together. Without this process, the cannabis oil would form a top layer.
One of the most challenging aspects of cannabis emulsions is maintaining stable potency levels. A cannabis beverage can be affected by oxidation, causing a change in the cannabinoid’s chemical structure. Oxidized THC converts to CBN. As THC is lost, CBN forms, which has different effects than THC.
Oxidation can occur from oxygen in water used for emulsification because oxygen has a higher solubility in the oil droplets than in the water. In addition, emulsification creates billions of small droplets, increasing the surface area that gets exposed to oxygen.
The risk of oxidation can increase due to metal ions in some beverage bases, such as non-alcoholic beer and wine. Increased oxidation can also occur during packaging. Reducing the oxygen level of the water base and removing oxygen in the last bottling step can help minimize cannabinoid loss due to oxidation.
In some cases, the types of ingredients used in the product can cause cannabinoid loss. For example, some beverages, such as pomegranate juice and infused red wine, contain high concentrations of polyphenol, a compound found in grape skin. Polyphenol combines with polysorbate, an emulsifier, and precipitates out, causing a reduction in potency.
Packaging material can also affect cannabinoid levels. For example, aluminum cans are sprayed with a thin layer of hydrophobic polymer on the inside to avoid corrosion caused by contact between the can and the liquid. However, this lining attracts the hydrophobic cannabis oil in the emulsion droplets. These droplets stick to the liner and reduce potency over time.
Glass is an alternative to aluminum cans and provides a hydrophilic surface, eliminating droplets sticking to the liner. Glass, however, is heavier and more costly to ship compared to lighter and cheaper aluminum cans. Processors should tailor their emulsions to a compatible liner material to reduce potency loss.
Clearer Extracts and No Cannabinoid Loss with Media Bros
Cannabis degradation is an ever-present risk for the cannabis industry from the moment the seed is planted to well after the customer has purchased the product. Media Bros has developed an innovative line of filter media that gives processors peace of mind, knowing they are removing unwanted pigments without sacrificing cannabinoid potency.
Whether you’re running a CO2, hydrocarbon, or ethanol extraction system, we’ve got the right color remediation solution for you. Level up low-quality trim and bring high-quality nug runs to new heights with adsorbent media that doesn’t slow down your process and preserves more of the plant’s cannabinoids and terpenes.