Chlorophyll is a tricky pigment in the cannabis industry. On the one hand, it has antioxidant and anti-inflammatory properties and helps plants grow, but on the other hand, chlorophyll can affect the cannabis product’s taste and color.
When you smoke it, it kind of tastes like grassy hay and can make edibles, tinctures, drinks, and extracts taste off and have a darker color.
Chlorophyll remediation removes the dark pigmentation and harsh flavor, leaving behind a smooth-tasting and clearer cannabis concentrate. Chlorophyll is essential in plant production, but can be easily removed in the processing stage to create a better tasting, better looking product.
What Is Chlorophyll?
Chlorophyll is the green pigment found in any plant and the most abundant pigment in the world. It is critical in the photosynthesis process, the chemical reaction that absorbs sunlight and produces sugar from carbon dioxide and water in plants.
Photosynthesis is vital to the survival of photosynthetic organisms like plants and algae. They are at the base of the food chain and are essential for all higher life forms, including for its production of most of the atmosphere’s oxygen.
Chlorophyll need high light intensity to trap red and blue light, which helps the plant grow and release oxygen.
Usually, chlorophyll is expressed by the presence of green coloration due to the way the pigment absorbs and reflects a light source. The absorbance of visible light by chlorophyll makes it possible for plants to have a vivid green color, so it is especially abundant in cannabis.
In plants, you can find different types of chlorophyll, which absorb red and blue light wavelengths. Chlorophyll is found in the chloroplasts on the plant cells. Chloroplasts are oval–shaped plastids responsible for storing energy and synthesizing metabolic materials.
Glucose from photosynthesis and nutrients are the plant’s energy source and used to produce cellulose and starch, the building blocks of plant cell walls, leaves, and other plant foliage. From one perspective, chlorophyll is the foundation for all living beings.
As a cannabis consumer and processor, the lack of chlorophyll in an extract or infused product actually adds value by improving its appearance, flavor, and smell. Understanding the life cycle of chlorophyll and the factors that affect it inform the removal/remediation process.
How Chlorophylls Work
In humans, sunlight can stimulate the production of previtamin D3, which turns into vitamin D, a fat-soluble vitamin that helps with bone and teeth growth and reduces the risk of certain diseases. Plants, however, can use sunlight for far much more than us through photosynthesis.
Plants capture light energy to make sugars from it. Pigments, such as chlorophylls and carotenoids, in the chloroplasts of plant cells absorb the light energy, a type of electromagnetic radiation that travels in waves. These photosynthetic pigments only absorb a certain range of wavelengths of visible light and reflect others. It is what gives plants their distinct color.
Carotenoids are pigments that produce yellow, red, and orange colors, found in many plants such as tomatoes, carrots, and pumpkins. Carotenoids help absorb light and also remove excess light energy and evaporate it as heat. Excess light can damage chlorophyll or form harmful reactive oxidative molecules.
Chlorophyll can be found in five types: chlorophylls a, b, c, and d, as well as an associated molecule found in bacteriochlorophyll prokaryotes. In plants, however, you will mainly find chlorophyll a and b, which help with photosynthesis and are essential for healthy plant growth.
Chlorophyll molecules have a hydrophobic tail that prevents the movement of water across its cell membrane. The tail fits into the thylakoid membrane and the porphyrin ring head, which has a magnesium atom in the center. This part of the chlorophyll absorbs the light energy.
Chlorophyll a and b absorb light, but chlorophyll a plays an important part in converting the light energy into chemical energy, which happens during the first photosynthesis stage through a series of light-dependent chemical reactions.
Because chlorophyll a plays an essential role in creating energy for the plant, other pigments, including chlorophylls and carotenoids, are called accessory pigments. These pigments allow plants to absorb a wider wavelength range and create more energy from light than with chlorophyll a alone.
Why Is Chlorophyll Green?
Chlorophyll is found in many leafy greens and cannabis. So, why does chlorophyll make plants green? It is because the pigment does not absorb green light wavelengths in white light, which features all colors in the color spectrum. Instead, chlorophyll reflects the green light wavelength, making the cannabis plant appear green.
In cannabis, chlorophyll content is significantly higher than other pigments in the plant, making the plant mainly appear green and other pigmentation not visible. For example, xanthophyll regulates temperature and light and appears yellow. Anthocyanins in plants can appear as purple or blue. That is why you may see these colors in cannabis buds, too.
The green color gives flower much of its jar appeal. Consider cannabis flower with a brownish or yellow color compared to a vibrant green color. Brown or yellow colors are a sign of poor cannabis quality. With aged cannabis that has lost a lot of chlorophyll, you can also assume that it has lost other therapeutic compounds like cannabinoids and terpenes.
How Lighting Affects Cannabis Plant Growth
In a cannabis grow room, the light quality and intensity, as well as the photoperiod are some of the most important factors in plant development and vary between vegetative and flowering stages. Higher light intensity is usually associated with higher cannabinoid concentrations.
Grow lights used in indoor cannabis production include high-intensity discharge (HID), light-emitting diode (LED), and fluorescent lights. High-pressure sodium (HPS) and metal halide lamps are types of HID lights.
Chlorophyll and chloroplasts in the plant canopy absorb various wavelengths, which fuel cannabis growth through the seedling, vegetative, and flowering stage. Getting the right lighting can give the plant’s the energy they need to grow leaves, stems, and eventually, flower buds.
Cannabis is a plant that thrives in high light levels and warm temperatures. The plant achieves the highest photosynthetic efficiency under ~1,500 photosynthetic photon flux density (PPFD) and 77-86º F (25-30º C). High photosynthesis rates, however, do not equal higher flower yields. The light saturation point for cannabis is unknown and refers to the light intensity at which photosynthetic activity reaches its maximum positive effect.
Plant-based foods, such as vegetables, fruits, nuts, and seeds, provide many health benefits and are indirectly a result of the efficiency of chlorophyll in plants. Chlorophyll, itself, is full of vitamins and antioxidants and is often marketed as having numerous health benefits, including helping to improve the immune system, increase energy levels, and reduce stress levels.
Despite the broad health claims, the research on chlorophyll’s health benefits needs more work. Larger controlled studies are necessary to confirm the results of studies on animals and small-scale human studies.
Still, there are several proven health benefits that make chlorophyll a superfood and valuable for many health-conscious consumers.Chlorophyll can be consumed from plants or supplements in liquid, spray, ointment, or tablet form.
Chlorophyll supplements actually contain chlorophyllin, a semi-synthetic chemical made from chlorophyll. The average dosages of chlorophyllin supplements range between 100 and 300 milligrams per day, taken over three doses.
Although chlorophyll may provide health and wellness benefits when consumed, in cannabis extracts and infused products, too much chlorophyll can actually negatively affect the taste and color. It is still crucial to understand how chlorophyll affects the body.
The following are some other benefits of chlorophyll:
Naturally-derived chlorophyll and chlorophyllin from supplements are generally safe to consume. However, people may experience some side effects such as digestive issues, diarrhea, itching or burning after topical application, and black, yellow, or green stool.
Before consuming chlorophyll regularly for its suggested and proven health benefits, consult with your doctor to determine if it could interact with your medications or treatment.
How Chlorophyll Content Affects Flower and Extract Quality
Chlorophyll is full of natural health benefits, but in cannabis it can contribute to a grassy flavor and plant-like aroma. Too much chlorophyll in flower, extracts, or infused products can give them a bitter flavor that can overpower their natural terpenes.
Consider the funky and gassy aroma of Gorilla Glue #4 (GG4). When excess chlorophyll is in the bud, the skunky, herbal, piney, and fuel-like smells of the plant’s terpenes are overshadowed by the green pigment. The smoking or vaping experience also suffers from chlorophyll-rich bud.
How does cannabis end up with too much chlorophyll for our liking? Poor drying and curing fail to remove the chlorophyll or a lack of post-processing during the extraction phase can leave behind this harsh-tasting pigment and create a darker-color extract.
How Drying and Curing Affects Chlorophyll Content
After harvesting cannabis plants, the drying and curing process helps remove excess moisture and chlorophyll to refine the bud’s flavor and aroma. This post-harvest process is especially helpful for cannabis flower products such as bud, pre-rolls, and moon rocks.
In addition, drying and curing cannabis helps remove the moisture, making it easier to light the bud or joint.
During the drying process, cannabis branches must be stored in a climate-controlled environment with the proper temperature, air flow, humidity, and lighting. Without the right environment in place, the bud quality, flavor, and aroma can be affected.
During the curing phase, cannabis buds are stored in airtight containers and regularly “burped” to let moisture and CO2 escape from the container. This process further reduces the chlorophyll content and let the strain’s true flavors get the spotlight.
As an alternative to dried and cured cannabis for processing, many companies are using fresh-frozen cannabis for its ability to preserve the plant’s most therapeutic compounds and allowing post-processing to remove the contaminants.
Why Choose Fresh-Frozen Cannabis for Extracts
Cannabis extractions usually use dried cannabis material (biomass) of various grades, from trim and shake to trichome-rich buds. As an alternative to cannabis that has undergone drying and curing, fresh frozen cannabis can provide a greater aroma, flavor, and experience.
Fresh-frozen cannabis is a process where the plant is harvested, frozen, and then stored in a temperature-controlled environment until it’s ready to be used. The process preserves the potency and flavor of cannabis flower while also keeping it fresh.
Not only does fresh frozen cannabis save processors weeks of time by forgoing the trimming, drying, and curing process, but they get to produce higher-quality extracts such as live resin and live rosin at a higher price.
How Chlorophyll Breaks Down
The breakdown of chlorophyll is a hallmark of fall, as the foliage of deciduous trees stop producing chlorophyll and turn red, yellow, orange, purple, and brown. The colorful change in foliage is visible everywhere, even from space.
Twenty years ago, the research into the breakdown of chlorophyll in plants was in its infancy. Over the last decade, researchers have come to a better understanding about the chlorophyll degradation process. The yearly turnover in chlorophyll has been estimated to be more than one billion tons.
In higher plants, including vascular plants like cannabis, chlorophyll a is the degradable chlorophyll form. When leaves deteriorate, chlorophyll b is converted to chlorophyll a by chlorophyll b reductase and 7-hydroxymethyl chlorophyll a reductase, which are enzymatic reactions that reduce a specific substance.
Chlorophyll a degrades when magnesium is removed to convert chlorophyll a to pheophytin a by magnesium-dechelatase, encoded by the Stay-Green (SGR) gene. Pheophytin a is then hydrolyzed by pheophytinase (PPH) to make pheophorbide a and phytol.
The green color of these simpler molecules is lost when the porphyrin ring of pheophorbide is split by the pheophorbide a oxygenase (PAO), an enzyme that accelerate oxidation, and produces an oxidized red chlorophyll catabolite (RCC).
Red chlorophyll catabolite reductase (RCCR) catalyzes RCC to produce primary fluorescent chlorophyll catabolite (pFCC). The pFCC is altered and transported into the vacuole and converted to a non-fluorescent product by acidic pH.
The plant’s growing environment and phytohormones have been thought to regulate the breakdown of chlorophyll. More research is needed into the roles and mechanisms of environmental factors and phytohormones in chlorophyll breakdown regulation.
In cannabis, like all plants, chlorophyll breakdown is visible through the color of its foliage. The vibrant green can dull over time, becoming yellow and brown.
Biomass Quality in Cannabis Extraction
Biomass refers to the buds and other parts of the plant, which can be mixed together. High-quality biomass usually has between 15-25% potency, while low-grade biomass can have about 5-15% cannabinoid and terpene potency.
For commercial cannabis processing, the quality of the biomass depends on many factors, including the trichome density, biomass components, smell, and color. High-quality biomass has a high trichome density, pleasant odor, and is mainly composed of buds, not leaves or stems.
In terms of color, biomass hues can range from a deep and vivid green to a yellow and brown in low-quality material. Biomass that is yellow or brown has not been dried or stored properly. This material also has a weaker potency, flavor, and aroma.
The lack of green pigmentation in the leaves means there is very little chlorophyll. As chlorophyll content goes down, other pigments appear.
Although lower quality biomass can be refined through extraction and post-processing, the quality still will not compare to using higher-grade biomass such as fresh-frozen material for live resin.
How to Remove Chlorophyll in Cannabis at Home
Home cooks and extractors may want to reduce the amount of chlorophyll that ends up in their edibles and extracts. Although there is no way to remove all of the chlorophyll at home, you can significantly reduce the amount that ends up in the final product.
- Dry and cure cannabis: Properly drying and curing cannabis after harvest is one of the best ways to reduce chlorophyll content. The harsh taste is removed, which allows the natural terpenes to shine through.
What Is Color Remediation?
In cannabis extraction, color remediation is a process that removes unwanted compounds from cannabis using a color remediation column (CRC). Color remediation is also commonly used in the production of food and wine. In wine production, enzymes and filters are used to remove bacteria and grape particles and make the wine more appealing and shelf-stable.
Cannabis processors use various filtration media in the CRC to filter certain compounds. Removal of these unwanted pigments, such as chlorophyll, can produce a clearer extract with a better flavor and aroma. Dark and brown extracts can come out much lighter than before.
Adsorbent Media in Color Remediation
Filtration media is the stationary phase of the CRC that can remove polar impurities, pesticides, and pigments. Activated charcoal, diatomaceous earth, activated bentonite clay, activated alumina, activated bleaching earth, and other adsorbents are used to remove impurities in extracts. Several media types can be used at the same time to remove more undesirables.
Adsorbent media can filter impurities from liquid or gas based on the molecule’s electrical attraction. Certain impurities can be attracted to the media and be filtered, while the rest of the purified oil goes straight through. Under the proper procedures, the filter media should not leak into the extract.
Color remediation gives processors more control over the end product’s color and can remove other unwanted compounds besides chlorophyll, including pesticides, plant sugars, and lipids.
Ethanol Extracts Require Chlorophyll Remediation
Ethanol as a solvent is commonly used for high-throughput hemp extraction. This solvent does a good job of extracting active cannabis compounds, but also ends up pulling out undesirable waxes and pigments, such as chlorophyll. Cold ethanol extractions and short extraction times can be used to reduce the chlorophyll in the end product.
Processors can remove pigments and waxes from ethanol extracts using various low-cost or high-tech methods:
Butane Hash Oil Preserves Cannabinoids and Terpenes
Butane hash oil (BHO) extraction is the best way to create flavorful and aromatic concentrates with less chlorophyll than other extraction methods and higher concentrations of cannabinoids and terpenes. In addition, BHO extractions can produce a broader range of concentrate forms, including budder, shatter, crumble, live resin, terp sauce, and more.
Butane and propane have relatively lower boiling points than other solvents, allowing processors to operate at lower temperatures and preserve the heat-sensitive compounds like terpenes, which can easily evaporate at high temperatures. Butane’s boiling point is 30.2º F and propane’s boiling point is -43.6º F.
Propane hash oil (PHO) extraction is not as common as BHO extraction. This method is performed at higher pressures and lower temperatures than BHO extraction and can lower the amount of unwanted plant material in the end product. Because propane has a lower boiling point than butane, it is better able to capture terpenes.
Because butane and propane are nonpolar, they do not extract water-soluble compounds like chlorophyll and other undesirable compounds. The result is a lighter-colored extract without the dark green or brown tint found in many low quality extracts.
A blend of propane and butane can be used to improve the extraction efficiency and yield, producing a more terpene-rich extract. Processors generally use a 70% butane and 30% propane blend to create aromatic and flavorful extracts with a light color.
Removing Chlorophyll from Cannabis with Color Remediation
Color remediation media, such as activated charcoal and bleaching clays, are loaded into the CRC under the biomass in a regular flow system or above the biomass in a reverse flow system. A color remediation system includes the column, filter media, flow controller, and paper filter.
Some filter media such as silica gel and bentonite clay must be heated before adding it into the CRC to prevent clogging and create an uninterrupted flow. The ratio of media per pound of biomass depends on the type of media, the biomass quality, and extraction equipment.
Adding enough filter media in a properly-sized CRC allows the crude extract to properly filter through the adsorbent material. We suggest using at least 6 inches of media in your column or find a way to reduce the flow in the column to give the extract enough residence time in the mediaf for proper filtration.
Sintered discs and mesh screens are used to prevent the filter media from ending up in the final product and require ultrasonic cleaning.
After the crude extract has gone through the filter media blend, it flows into the recovery tank with a clearer color.
Why Is Color Remediation Controversial?
One of the most common gripes from consumers about extracts that have undergone color remediation is that processors are duping them into buying low-quality, or sometimes, unsafe cannabis oil. That is not true.
Color remediation only removes the pigments and contaminants from the crude extract. It does not add or remove the cannabinoids and terpenes from the end product. So, if you’re starting with low-grade trim for your extracts, your extract quality is still relatively poor compared to extracts made from fresh-frozen cannabis, only the color and taste will be improved.
Color remediation processes are not trying to pull one over customers. Companies still have to meet testing regulations for pesticides, heavy metals, and residual solvents. Unlicensed companies, however, are not regulated, and therefore, produce unsafe products.
Most extraction companies already use some form of color remediation. While there can be some risks of contamination in poor operating procedures, new tech and an optimized extraction workflow eliminates the risk of leaking filter media in the product or removing terpenes.
Does CRC Reduce Yield?
Getting rid of chlorophyll pigments can improve the color of extracts without significantly affecting the yield. The filter media can cause an insignificant reduction in yield because it is taking out the undesirable compounds, but provides better flavor and color.
Ultrasonic Bleaching Hemp Seed Oil
Cold-pressed Cannabis sativa hemp seed oil does not contain any cannabinoids and terpenes, but may provide several health benefits due to its fatty acid ratio. Benefits include healthier skin, lower blood pressure, better heart health, pain relief, and reduced inflammation.
Hemp seed oil is often light or dark green in color and has a grassy taste due to the natural chlorophyll concentration. Ultrasonic bleaching and heat can be used to remove the excess chlorophyll from the solution.
In one study on the effects of chlorophyll reduction in cold-pressed hemp, researchers found that activated bentonite, industrial clay, and sepiolite significantly reduced the chlorophyll content and enhanced oxidative stability.
The results indicate that the quick removal of chlorophyll from hemp seed oil is improved with the combination of ultrasonic treatment and bleaching clay.
Make Better Cannabis Extracts with Media Bros
Chlorophyll and other undesirables can ruin an otherwise good extract. Media Bros offers innovative filter media for BHO, ethanol, and CO2 systems. No matter what extraction system you are running, Media Bros can provide extract clarification without affecting the overall quality.
Start making the best extracts possible by incorporating CRC to your extraction workflow. Reach out to us via email or phone to schedule a consultation or request a sample and see the magic happen for yourself.