Grow, harvest, test, grind, decarboxylate, test again, extract… What’s next? Depending on your extraction method of choice, it is very likely that the next step in creating your hemp or cannabis concentrate will involve winterizing wax and filtering your mixture to begin the distillation process. Be Winterization is necessary to create a higher purity of cannabinoids. Removing lipids results in a higher quality product. One of the most critical steps in terms of making a clean cannabis product is CBD winterization. If you’ve ever wondered what that means, click to learn more!
What You Should Know About Filtration, Winterizing Wax and CBD Extraction
Grow, harvest, test, grind, decarboxylate, test again, extract… What’s next? Depending on your extraction method of choice, it is very likely that the next step in creating your hemp or cannabis concentrate will involve winterizing wax and filtering your mixture to begin the distillation process. Because the crude oil that is created with methods like supercritical CO2 extraction will often contain waxes and lipids, it becomes important to remove them to create a quality final product for the consumer. So, let’s take a look at this important process and why supercritical CO2 extraction benefits from it.
What is Winterization?
Winterization is the process of removing fats and waxes from the hemp extract. The process involves dissolving the CBD oil coming out of the CO2 extractor in food grade ethanol and subsequently chilling the ethanol oil mixture down to -20 degrees Celsius. The fats and waxes are less soluble at those temperatures and they will precipitate while the cannabinoids remain in solution. The fats and waxes are then filtered before solvent removal.
Why Winterize and Filter Your Oil?
Depending on the product that is being created, remaining waxes and lipids can cause a number of issues for both producers and consumers: For the producer, remaining waxes and lipids can dilute product potency, and cause a lesser quality distillate overall. Quality and clarity of a hemp or cannabis extract often go hand-in-hand, and remaining waxes can cause a final distillate to be cloudy or of undesired consistency – not the result a producer wants to see after all the hard work.
For the consumer, waxes and lipids left in an extract can result in a shoddy product as well. For example, smokeable cannabis extracts or “dabs” as they are often called can come in the form of what is called “shatter” given its translucent clarity and breakable consistency similar to glass.
Both clarity and consistency mean quality shatter and a happy customer, but when residual waxes are left in the product it can cause what is called nucleation making that clear, brittle shatter turn into a soft, sticky opaque consistency.
Furthermore, fats and waxes left in any cannabis concentrate can be harsh or have undesirable tastes when smoked or vaporized. Because of this, it is very important to properly winterize and filter those remaining waxes and lipids. And, there are many methods to do this.
As a proud proponent of supercritical CO2 extraction, extraktLAB does not use denatured ethanol for an extraction method for a number of reasons. However, a common method of winterizing wax involves the use of ethanol. So, we often face a recurring question in the dewaxing process…
Why Use CO2 Extraction When You Use Ethanol for Winterization?
Though it is undoubtedly the cleaner extraction solvent, biomass, fatty acids, waxes and resins can be co-extracted along with the cannabidiol and other cannabinoids when CO2 is used to extract hemp. The amount that is extracted depends on the pressure of the CO2 extraction.
In general, the higher the pressure and longer the runtime, the more acids and waxes will be extracted. Low pressure CO2 extraction methods, known as subcritical CO2 extraction, produce extracts that require very little post processing.
Many companies actually skip the winterization process depending on what they are using the oils for. The trade-off for lowering the extraction pressure to subcritical is that the run time increases greatly. The flow rate must be increased to compensate for the lower run time. In the case of our extraction equipment, the flow rate increases as the pressure goes down so those customers desiring runs of critical methods are able to do so with significant efficiency.
In the case of supercritical CO2 extraction, winterization is likely going to be needed. The cannabinoids and CBD oils that remain in the solution are then introduced into a falling film evaporator. The ethanol is removed from the solution and may be recycled once it has been re-conditioned and tested for reuse. The amount of ethanol that is used in the winterization process is very small compared to the amount of ethanol that is used during an ethanol extraction.
For example, one gallon of ethanol is required to fluidize one pound of hemp for ethanol extraction. 1000 lb of hemp by extension requires 1000 gallons of ethanol. In contrast, 1000 lb of hemp at 10% cannabinoid will produce approximately 100 lbs of CBD oil. 100 lb of CBD oil – Approximately 30 gallons Of CBD oil, so 180 gallons of ethanol is needed to winterize 30 gallons of CBD oil.
Why is the Winterization Process Important in Cannabis Oil Extraction?
The winterization process, in simple terms, is the removal of fats, lipids and other unwanted materials from crude oil extract. Winterization is necessary to create a higher purity of cannabinoids. Lipids dilute the cannabinoid fraction, therefore removing them results in a higher quality product.
The transparency of the product is also affected by lipids in distillate. When lipids are not removed, the distillate will not be transparent – this is a sign of a lower-quality and lower-valued product.
Another adverse effect that lipids have in distillate is the way that they burn on coils in vape pens. Lipids will make the vape pen taste burnt which is unsatisfactory to the consumer. Winterization is a key process that differentiates a product from being either low quality or high quality. That directly affects the value of the product that you are creating.
What is the winterization process?
During winterization, a non-polar oil extract is dissolved into ethanol or other polar solvent. The solution is placed in sub-zero temperatures (usually in the range of -20 to -80 degrees Celsius). When using ethanol, the ratio of ethanol to extract is often 10mL ethanol to 1g of oil. However this ratio often ranges between 5ml to 1g and 20ml to 1g.
During this process in the sub-zero temperatures, the lipids float to the top of the solution because of their lower solubility. The ideal time to leave the solution in cold temperatures is at least 24 hours.
There are multiple filters that the solution can go through such as paper filters and metal micro-filters. The lipids are filtered out of the solution through the filtration process and what is left is a high-purity distillate.
Why is winterization important in the cannabis and hemp oil extraction process?
To truly compete in the cannabis and hemp oil industry, winterization is a vital process. As mentioned previously, a winterized solution has more value than a solution that is not winterized.
Not only is value a factor, but customer satisfaction also plays a big role in this process. When an extract has fat and lipids left in it, it burns, vapes and tastes bad. Consumers will not buy this low-quality product again.
The saying “look good, feel good” does not only apply to people, it also applies to distillate. Everyone likes a shiny new product, not a cloudy and murky one. This is especially true for distillate consumers as transparency is an easy indicator of the level of purity in an extract. To ensure that a product can compete in the cannabis industry, winterization must be included in the extraction process.
Want to learn more about the winterization process and how Maratek can help automate and perfect the process with our expertly engineered Turnkey Automatic Winterization System (TAWS)? Contact us today. We would love to answer any questions that you may have.
What is CBD winterization?
There are many steps to processing hemp into a consumer-level product. One of the most critical, in terms of making a clean product, is winterization. No, this isn’t what your dad does to the lawnmower every fall. Winterization is a process that removes undesirable elements extracted from hemp, for example, fats, waxes, and lipids leaving behind clean, consumable CBD oil. Without CBD winterization, these unwanted materials would cause the final product to be cloudy, darker, and have an unpleasant taste.
What steps come before the winterization of oil?
The winterization process starts with raw extract straight from our CO2 machine (see photo below). This CBD crude oil contains all the essential parts of the hemp plant except for the actual plant material itself. CBD, minor cannabinoids, terpenes, fats, waxes, and lipids are all part of this viscous liquid. Crude oil extracted from a CO2 machine will have an attractive, light color to it, especially compared to alcohol extracted oil, which will have a dark, sludge-like appearance.
What is CBD Winterization?
The CBD crude oil is combined with 200 proof alcohol and stirred vigorously until completely mixed. The alcohol is used to thin the crude oil out, as the desirable parts of crude will go into solution with the alcohol while the undesirable parts will coagulate and freeze allowing them to be filtered out. The mixture is then placed in a deep freezer at below-zero temperatures. Once it has time to freeze it looks cloudy and is ready for filtration. The next step is to place the mixture in vessels that use paper filters to remove the frozen fats, waxes and lipids. The actual CBD oil remains with the alcohol solution and passes through the filter while the frozen undesirable parts are caught by it. The photo below shows what a filter will look like after the solution passes through it. When properly winterized, the filters will catch all of the frozen plant waxes from the oil, leaving them sitting on top. Once the pass is complete, the filters and waxes are discarded. The clean oil flows through the filter into a collection vessel where it is refrozen for more passes. We winterize multiple times just to make sure that our oil is 100 percent clean!
So wait, even though the winterized oil is CO2 extracted, it will still contain alcohol?
Nope! The alcohol is just used to thin the CBD oil in order to properly filter it. Once it’s been filtered and the undesirable elements have been removed, it’s time to remove the alcohol. This is done with a piece of equipment called a rotary evaporator (rotovap). This is CEO Craig Henderson, who started refining hemp from the garage of his home, using a rotovap in the early days of Extract Labs. This bad boy is an efficient way to quickly distill the alcohol out of the solution. The bulb spins in a hot water bath while the system is under vacuum, allowing the alcohol to evaporate out while leaving the winterized oil spinning in the bulb. The alcohol vapors then travel up to the chiller coils where they condense into a liquid and drip down for collection. The alcohol is then recycled into our process. Once the rotovap is done with a work order, the spinning bulb will contain only clean winterized CBD oil. The winterized CBD is then ready to move on to the next phase of the process. From here, the winterized oil will be formulated into tinctures or it will move to our distillation department for further refinement.