CBD Oil Distillation Process

CBDISTILLERY

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Controlling the temperature for CBD and THC extraction and distillation is absolutely essential to managing final product quality and characteristics. Hemp (Cannabis sativa L.) synthesizes and accumulates a number of secondary metabolites such as terpenes and cannabinoids. They are mostly deposited as resin into the glandular trichomes occurring on the leaves and, to a major extent, on the flower bracts. In the last few years, hemp for production of high-value chemicals became a major commodity in the U.S. and across the world. The hypothesis was that hemp biomass valorization can be achieved through distillation and procurement of two high-value products: the essential oil (EO) and cannabinoids. Furthermore, the secondary hypothesis was that the distillation process will decarboxylate cannabinoids hence improving cannabinoid composition of extracted hemp biomass. Therefore, this study elucidated the effect of steam distillation on changes in the content and compositional profile of cannabinoids in the extracted biomass. Certified organic CBD-hemp strains (chemovars, varieties) Red Bordeaux, Cherry Wine and Umpqua (flowers and some upper leaves) and a T&H strain that included chopped whole-plant biomass, were subjected to steam distillation, and the EO and cannabinoids profile were analyzed by gas chromatography-mass spectrometry (GC–MS) and HPLC, respectively. The distillation of hemp resulted in apparent decarboxylation and conversion of cannabinoids in the distilled biomass. The study demonstrated a simple method for valorization of CBD-hemp through the production of two high-value chemicals, i.e. EO and cannabinoids with improved profile through the conversion of cannabidiolic acid (CBD-A) into cannabidiol (CBD), cannabichromenic acid (CBC-A) into cannabichromene (CBC), cannabidivarinic acid (CBDV-A) into cannabidivarin (CBDV), cannabigerolic acid (CBG-A) into cannabigerol (CBG), and δ-9-tetrahydrocannabinolic acid (THC-A) into δ-9-tetrahydrocannabinol (THC). In addition, the distilled biomass contained CBN while the non-distilled did not. Distillation improved the cannabinoids profile; e.g. the distilled hemp biomass had 3.4 times higher CBD in variety Red Bordeaux, 5.6 times in Cherry Wine, 9 times in variety Umpqua, and 6 times in T&H compared to the original non-distilled samples, respectively. Most of the cannabinoids remained in the distilled biomass and small amounts of CBD were transferred to the EO. The CBD concentration in the EO was as follows: 5.3% in the EO of Umpqua, 0.15% in the EO of Cherry Wine and Red Bordeaux and 0.06% in the EO of T&H. The main 3 EO constituents were similar but in different ratio; myrcene (23.2%), (E)-caryophyllene (16.7%) and selina-3,7(11)-diene (9.6%) in Cherry Wine; (E)-caryophyllene (~ 20%), myrcene (16.6%), selina-3,7(11)-diene (9.6%), α-humulene (8.0%) in Red Bordeaux; (E)-caryophyllene (18.2%) guaiol (7.0%), 10-epi-γ-eudesmol (6.9%) in Umpqua; and (E)-caryophyllene (30.5%), α-humulene (9.1%), and (E)-α-bisabolene (6.5%) in T&H. In addition, distillation reduced total THC in the distilled biomass. Scanning electron microscopy (SEM) analyses revealed that most of the glandular trichomes in the distilled biomass were not disturbed (remained intact); that suggest a possibility for terpenes evaporation through the epidermal membrane covering the glandular trichomes leaving the cannabinoids in the trichomes. This explained the fact that distillation resulted in terpene extraction while the cannabinoids remained in the distilled material. Cannabis distillation uses low pressures, gentle heating, and smart evaporation techniques to weed out only the purest cannabinoid liquid oil from crude.

Temperature Control for CBD/THC Extraction and Distillation

The legalization of the hemp cannabis derivative CBD and of marijuana and its THC derivative for medical and recreational purposes in many US states and all of Canada has led to significant economic growth in the CBD/THC extraction and distillation equipment sector. Many of the manufacturers of these two categories of equipment have been in business for a number of years, and the processes used for extraction and distillation have been refined over decades since they are used to extract and purify many different organic substances, chemical, petrochemical and alcoholic beverages. However, hemp and marijuana have their own unique characteristics, and the processes to extract and purify CBD and THC from their respective plant sources are still being fine-tuned by processors and original equipment manufacturers (OEMs).

There are quite a few different approaches to extraction and distillation of CBD/THC products, and each has certain benefits as well as some less desirable side effects; but they all have in common these parameters that need to be controlled: temperature, pressure or vacuum, source material throughput volume, and for extraction, solvent feed rate.

Extraction Process – Temperature control considerations

Current extraction processes include CO2, butane or propane, and ethanol. In each of these methods, the extraction agent is cooled down to temperatures that can reach -80°C (-176°F) and then compressed until it is liquefied. The temperature reduction is achieved using a chiller, which can be a standard piece of equipment or a custom unit designed to meet unique temperature profile requirements.

In commercial systems, extraction is typically performed in a jacketed vessel. Water, oil or other liquids are circulated within the jacket by a temperature control unit (TCU) which maintains consistent vessel wall and extraction chamber temperatures.

Temperature control is necessary throughout all the steps in the process, but precise extraction chamber temperature control is absolutely essential to managing final product quality and characteristics. This high level of control must also be replicable from one batch to another and in fact on a continuing basis over a large number of batches. Controlling temperature to within .275°C (.5 °F) is a standard that permits a consistent finished product. It is also important to note that repeatability, in addition to accuracy is extremely important for producers as it allows them to replicate the process over time, and thus insure consistent product quality.

For example, increasing the extraction temperature from the initial agent temperature can:

  • decrease the concentration of terpenoids in the extract
  • risk denaturing the final CBD/THC product
  • increase wax/resin extraction and overall volume, but yield a lower quality product

Similarly, decreasing extraction temperature can lead to:

  • increase the concentration of oil in the extract
  • reduce the wax proportion of the extract

For these reasons, having equipment that is capable of consistent and accurate temperature control is very important to producers; and as there is demand for many variations of this extraction process’ final product, chilling equipment and temperature control units with high precision, closed loop controls are critical.

Once the extraction process is complete a processor is left with “crude extract” that is 55-75% cannabinoid and that may in some instances, be sold without any further processing. For the majority of processors however, further separation of the remaining elements is necessary to obtain fully purified, high value CBD/THC oil.

The next step in the purification process is to remove waxes by cooling the extract down to approximately -20°C (-4°F) in a chiller-driven jacketed vessel. This “winterization” process precipitates some of the undesired elements out of the solution which after filtering, leaves oil made up of cannabinoids, chlorophyll and terpenes. Decarboxylation is an important step that may be performed either before or after the winterization process. It is used to activate CBD/THC components and is accomplished by carefully heating an extracted solution to release the carboxyl ring group (COOH).

Distillation Process – Temperature control consideration

A distillation process is then conducted to complete the separation of the remaining elements and produce the purest possible CBD or THC oil. It is worth noting that even though a source material has been winterized, as much as 40% of the remaining feedstock may consist of undesirable materials. Also, in the case of ethanol extraction, ethanol must then be evaporated to separate it from CBD/THC components.

As in the extraction process, the distillation process that is used to fully purify CBD/THC oils requires closely controlled temperature, pressure and source material feed rates to ensure that the necessary interactions produce a high-quality finished product with characteristics that generate the highest possible value.

The most common pieces of equipment are wiped film, molecular short-path stills. In this approach, the feedstock of oil is fed into a jacketed vessel that is often heated with an oil circulating TCU to achieve temperatures up to 343°C (650°F), though the typical distillation temperature range is 130 -180°C (266-356°F). In these systems, the feed stock is distributed on the evaporation chamber wall with a special wiper. The resulting thin film allows the more volatile terpenes to evaporate through the top of the chamber into their own external collection vessel, while the CBD/THC is collected along a TCU controlled central condenser unit which is cooler (typically 60-70°C / 140-158°F) than the evaporation chamber and serves to attract the cannabinoid vapor. The final step in the process is solvent removal, which is accomplished in a separate, external cold trap, which is also temperature controlled with a chiller.

Certain OEMs offer wiped film molecular short-path distilling equipment that integrates the removal of heavier materials directly into their distilling process. In this instance, chlorophyll, waxes and other heavier residue (up to 40% of the feed stock) descend the outer wall of the distillation vessel and are collected in their designated container.

In certain cases, a final separation step is taken to separate THC from CBD. Crystallization is a common method. A reactor vessel is filled with feedstock and a solvent which is chilled slowly from 60°C to -20°C. A slurry results and that is transferred to a Nutsche filter dryer to produce pure, dried crystals. The Nutsche filter is a jacketed vessel whose temperature is controlled with a circulating hot oil unit. The process results in a 98% or higher purity of the CBD or THC product.

Delta T Systems – Your partner in Pure Temperature Control

Delta T Systems has worked with extraction and distillation equipment manufacturers as well as end user engineering groups for over 25 years. The products we offer are designed to specifically address customers’ production needs. That is why so many customers return to us and choose our equipment over and over again as their production needs expand. We offer industry leading design, efficiency and service.

Delta T Systems has developed a broad range of industry leading product features and capabilities that make our TCUs and chillers the best on the market:

Chillers

  • Capabilities from 1-60 tons (higher capacities offered as custom designs)
  • Variable speed design that can cut energy usage up to 50%
  • Standard operating range from -18°C to 27°C (0°F to 80°F)
  • Highly accurate closed loop temperature control to .275°C (.5°F)
  • Data logging with remote control and analysis tools
  • Industry 4.0 ready
  • Long life heat exchange materials and low maintenance design

Temperature Control Units (TCUs)

  • Water Circulating Temperature Control Units (TCU) will perform in processes up to 300°F (149°C)
    • ¾ to 7 ½ HP Pump, 25 to 150 GPM
    • 9 to 144 KW Low Watt Density Heater
    • 149°C (300°F) Fluid Operating Temperature
    • 6, 12, 18, 24 or 36 KW Heaters, or special designs up to 360 KW
    • Maximum Operation Temperature up to 343°C (650°F)
    • 10 to 150 GPM Pumping Capacity
    • Heating Only or Heating with Cooling Capabilities

    Custom engineered product development and designed solutions are our specialty

    • Made to address customers’ unique needs
    • Custom design chillers and TCUs available for greater capacities

    For CBD or THC extraction and distillation temperature control, Delta T Systems has the experience, expertise and capability to give processors and OEM equipment manufacturers standard or custom equipment to meet all aspects of the process’ requirements. All systems are designed for process repeatability. Our equipment lowers production costs, improves temperature accuracy, and delivers long lived quality and ease of maintainability.

    Dan Brandenburg, Director of Sales & Marketing at Delta T Systems can be contacted for more information (262) 628-0331.

    © 2022 Delta T Systems. All rights reserved.

    2171 Highway 175 • Richfield, Wisconsin 53076
    262.628.0331 • 800.733.4204 • fax: 262.628.0332 Email

    Valorization of CBD-hemp through distillation to provide essential oil and improved cannabinoids profile

    Hemp (Cannabis sativa L.) synthesizes and accumulates a number of secondary metabolites such as terpenes and cannabinoids. They are mostly deposited as resin into the glandular trichomes occurring on the leaves and, to a major extent, on the flower bracts. In the last few years, hemp for production of high-value chemicals became a major commodity in the U.S. and across the world. The hypothesis was that hemp biomass valorization can be achieved through distillation and procurement of two high-value products: the essential oil (EO) and cannabinoids. Furthermore, the secondary hypothesis was that the distillation process will decarboxylate cannabinoids hence improving cannabinoid composition of extracted hemp biomass. Therefore, this study elucidated the effect of steam distillation on changes in the content and compositional profile of cannabinoids in the extracted biomass. Certified organic CBD-hemp strains (chemovars, varieties) Red Bordeaux, Cherry Wine and Umpqua (flowers and some upper leaves) and a T&H strain that included chopped whole-plant biomass, were subjected to steam distillation, and the EO and cannabinoids profile were analyzed by gas chromatography-mass spectrometry (GC–MS) and HPLC, respectively. The distillation of hemp resulted in apparent decarboxylation and conversion of cannabinoids in the distilled biomass. The study demonstrated a simple method for valorization of CBD-hemp through the production of two high-value chemicals, i.e. EO and cannabinoids with improved profile through the conversion of cannabidiolic acid (CBD-A) into cannabidiol (CBD), cannabichromenic acid (CBC-A) into cannabichromene (CBC), cannabidivarinic acid (CBDV-A) into cannabidivarin (CBDV), cannabigerolic acid (CBG-A) into cannabigerol (CBG), and δ-9-tetrahydrocannabinolic acid (THC-A) into δ-9-tetrahydrocannabinol (THC). In addition, the distilled biomass contained CBN while the non-distilled did not. Distillation improved the cannabinoids profile; e.g. the distilled hemp biomass had 3.4 times higher CBD in variety Red Bordeaux, 5.6 times in Cherry Wine, 9 times in variety Umpqua, and 6 times in T&H compared to the original non-distilled samples, respectively. Most of the cannabinoids remained in the distilled biomass and small amounts of CBD were transferred to the EO. The CBD concentration in the EO was as follows: 5.3% in the EO of Umpqua, 0.15% in the EO of Cherry Wine and Red Bordeaux and 0.06% in the EO of T&H. The main 3 EO constituents were similar but in different ratio; myrcene (23.2%), (E)-caryophyllene (16.7%) and selina-3,7(11)-diene (9.6%) in Cherry Wine; (E)-caryophyllene (~ 20%), myrcene (16.6%), selina-3,7(11)-diene (9.6%), α-humulene (8.0%) in Red Bordeaux; (E)-caryophyllene (18.2%) guaiol (7.0%), 10-epi-γ-eudesmol (6.9%) in Umpqua; and (E)-caryophyllene (30.5%), α-humulene (9.1%), and (E)-α-bisabolene (6.5%) in T&H. In addition, distillation reduced total THC in the distilled biomass. Scanning electron microscopy (SEM) analyses revealed that most of the glandular trichomes in the distilled biomass were not disturbed (remained intact); that suggest a possibility for terpenes evaporation through the epidermal membrane covering the glandular trichomes leaving the cannabinoids in the trichomes. This explained the fact that distillation resulted in terpene extraction while the cannabinoids remained in the distilled material.

    Introduction

    Industrial hemp (Cannabis sativa L.) was grown as a commodity fiber crop in North America until the mid-1930s. Hemp was banned and was considered an illegal crop in the United States for several decades. In 2014, section 7606 of the U.S. Congress Agricultural Act of 2014, the “Farm Bill”, authorized pilot programs on cultivation of industrial hemp, defined as “the plant Cannabis sativa L. and any part of such plant, whether growing or not, with a delta-9 tetrahydrocannabinol (THC) concentration of not more than 0.3% on a dry weight basis”. The 2018 Farm Bill decriminalized cultivation of industrial hemp and designated the U.S. Department of Agriculture (USDA) Agricultural Marketing Service to develop regulations. Hemp production in the U.S. is increasing rapidly and there were up to 500,000 licensed acres to grow hemp in 2019 1 , that would have produced $11.3 billion of income, or around 6% of the total value of all cash crops in this country 1 . Currently, at least 47 states have passed legislation to establish hemp production programs or allow for hemp cultivation research. At this time, hemp is prohibited only in Idaho, and Mississippi. Specific state legislation varies from state to state. Currently, Oregon legal environment with respect to commercial hemp production is among the most reassuring in the U.S. and hence, stimulating hemp production for high-value chemicals.

    Most of the hemp grown in the U.S. is for production of high-value chemicals such as cannabinoids and terpenes. Essential oil (EO) production is a novel use of hemp, and as such, it needs to be researched. Hemp for EO and cannabinoids production is an understudied, high-value crop, with many pending unanswered questions.

    Hemp synthesizes and accumulates numerous secondary metabolites 2,3,4 . The most important of these are the cannabinoids and terpenes; they are toxic to many organisms and are considered to be plant protective chemicals. Hemp chemicals have numerous uses due to their bioactivities 5,6,7,8,9,10 .

    Hemp (C. sativa) is an annual, normally wind pollinated dioecious plant (separate male and female plants), although monoecious forms can also occur naturally. Botanically, hemp belongs to Cannabaceae. There has been a debate on whether hemp is a single species or include other species such as Cannabis indica Lam. and Cannabis ruderalis Janisch. Small and Cronquist 11 separated the species into two subspecies, subsp. indica (Lam.) E. Small & Cronq., with relatively high amounts of the psychotropic constituent THC, and subsp. sativa with low amounts of THC. According to this systematics, the modern fiber and grain industrial hemp varieties would belong to subsp. sativa. Therefore, most recreational, or medical marijuana varieties and strains would belong to subsp. indica. However, there are numerous hybrids blurring the line. Overall, botanists consider C. sativa to be a single species with several subspecies 12,13,14 .

    Hemp plants form different epidermal trichomes, which are considered defense structures to reduce herbivory by making the biomass less palatable. Cystolith trichomes contain calcium carbonate particles. These trichomes are present in great numbers on both leaf surfaces along with the slender non glandular trichomes 13 . In addition, hemp forms secretory or glandular trichomes, the sites for EO (terpenes) synthesis and accumulation, with the highest density in non-fertilized flower bracts (Figs. 1, 2). Current understanding is that secretory trichomes are also the site where cannabinoids are synthesized and accumulate 3,14,15 . Most of the hemp chemicals are produced in multicellular glandular trichomes, which can be sessile glands (with very short stalks), or long-stalk secretory glands (Figs. 1, 2). The top of these glands is a cavity covered by a waxy cuticle, where the resin (a mix of cannabinoids and terpenes) is accumulated. Since the waxy cuticle of the glands is a thin layer, it can easily be ruptured resulting in a release of its contents. The density of secretory glands differs, with the highest concentration found in perigonal bracts covering the female flowers. Therefore, traditionally, flowers have been the plant part of the most interest because of their high content of various natural products 2,14,15 .

    (A) Hemp abaxial (lower) leaf surface with glandular trichomes, and slender cystolithic non glandular trichomes. (B) Hemp adaxial (upper) leaf surface with an abundance of cystolithic trichomes and few sessile glandular trichomes. (C) Hemp leaf petiole with an abundance of cystolithic and slender non glandular trichomes and few sessile glandular trichomes. (D) Flower bract densely covered with glandular trichomes. (E) Close up of flower bract with glandular trichomes and slender non glandular trichomes. (F) Detached sessile glandular trichomes from hemp leaves.

    Non-extracted Red Bordeaux flower part with glandular trichomes.

    Hemp plants contain a whole array of chemicals that may act synergistically or antagonistically. Currently, the pharmacological power of the C. sativa is based on the content of δ-9-tetrahydrocannabinolic acid (THC-A) and cannabidiolic acid (CBD-A) 16 . Other major cannabinoids include cannabinolic acid (CBN-A), cannabigerolic acid (CBG-A), cannabichromenic acid (CBC-A), and cannabinodiolic acid (CBND-A) 2,17 . With recent legalization of hemp in many countries, researchers are now focusing on better understanding of the role of various other chemicals found in hemp 2,18 . Terpenes (that are constituents of the hemp EO) contribute to the aroma of various hemp genotypes, and so far, around 140 different terpenes have been reported in hemp 2,14,19,20 . The major ones belong to the class of monoterpenes (e.g., α-pinene and myrcene) and sesquiterpenes ((E)-caryophyllene, and caryophyllene oxide) 21 .

    The hypothesis was that CBD-hemp biomass valorization can be achieved through distillation and production of two high-value products: EO and cannabinoids. Furthermore, a preliminary distillation process may decarboxylate cannabinoids and therefore improve cannabinoid composition of extracts from the residual biomass.

    Results

    Essential oil (EO) content (yield) and composition of Cherry Wine (CW), Red Bordeaux (RB), Umpqua (Umpq) and T&H

    The EO yield (% in dry biomass) was highest in CW and RB (1.85 and 1.6%, respectively), lower in Umpqua (0.72%), and the lowest in T&H (0.37%) strains (Table 1). The lower EO content in T&H was most probably because the biomass was chopped by the grower; it included all plant parts (stems, leaves, flowers), and therefore there is dilution factor in addition to the chopping that may have destroyed some of the glandular trichomes resulting in terpene evaporation.

    Table 1 Essential oil yield and composition obtained by non-stop steam distillation for 240 min of autoflower type hemp biomass of Cherry Wine organic (CW), Red Bordeaux organic (RB), Umpqua organic (Umpq), and non-stop steam distillation for 120 min of chopped biomass of autoflower type hemp T&H.

    The EO chemical profile of the four strains was also different. Cherry Wine and Red Bordeaux had higher concentrations of myrcene compared with Umpqua and T&H. Limonene was around 4–5% in Cherry Wine, Red Bordeaux and Umpqua but < 1% in T&H. Conversely, (E)-caryophyllene was much higher in T&H (30.1%) and lower in the other 3 hemp strains. α-trans-Bergamotene was also higher in T&H and much lower in the other 3 hemp strains.

    α-Humulene and α-bulnesene, (E)-α-bisabolene, caryophyllene oxide, and epi-α-bisabolol were also higher in the EO of T&H and lower in the EO of the other three strains. The highest concentration of guaiol, 10-epi-γ-eudesmol, bulnesol, and cannabidiol (5.3%) were found in the EO of Umpqua. The concentration of cannabidiol was < 0.2% in the EO of the other three strains. α-Guaiene was only found in T&H and in Umpqua, cannabidivarin and cannabicitran were only detected in the EO of Umpqua, (E,E)-α-farnesene (2.1%) was only found in the EO of T&H.

    Cherry Wine EO contained myrcene (23.2%), (E)-caryophyllene (16.7%), selina-3,7(11)-diene (9.6%), as the three main constituents (> 10% of total oil) (Table 1). The Red Bordeaux main EO constituents were (E)-caryophyllene (~ 20%), myrcene (16.6%), selina-3,7(11)-diene (9.6%), and α-humulene (8.0%).

    The EO of Umpqua had (E)-caryophyllene (18.2%) as the main constituent, other constituents included guaiol (7.0%), 10-epi-γ-eudesmol (6.9%), selina-3,7(11)-diene (5.6%), cannabidiol (5.3%), and α-humulene (5.3%). (E)-Caryophyllene (30.5%) was the main constituent of T&H strain; other constituents included α-humulene (9.1%), (E)-α-bisabolene (6.5%), epi-α-bisabolol (6.0%), α-bulnesene (6.0%), and caryophyllene oxide (5.1%) (Table 1).

    Effect of distillation on cannabinoids

    The distillation of hemp biomass resulted in two high-value products: essential oil (EO) and distilled biomass with largely preserved but altered cannabinoids because of the decarboxylation that occurs during the distillation. Most notable, the distillation of hemp resulted in apparent decarboxylation and conversion of cannabinoids in the distilled biomass. One of the notable conversions of interest is the decarboxylation of CBD-A into CBD (Table 2). This was observed in all four different strains (chemovars). Distillation of the biomass slightly increased the concentration of total CBD in Cherry Wine and decreased it slightly in Red Bordeaux. Overall, the total CBD ranged from 2.3 to 11.7% and from 2.1 to 12.7% in the non-distilled and distilled biomass, respectively.

    Table 2 Cannabinoid content (%) in distilled and not distilled biomass of 4 varieties, transplanted autoflower type hemp plants (mean ± std.err.; n = 2).

    Similarly, distillation resulted in the decarboxylation of CBC-A into CBC; the concentration of CBC in the distilled biomass increased 4.1, 2.8, and 5.2 times in Cherry Wine, Red Bordeaux, Umpqua relative to the non-distilled biomass, respectively, and from 0 to 0.123%, in T&H. There was concomitant decrease of CBC-A from non-distilled to distilled biomass.

    Similar tendency was observed with the conversion of CBG-A into CBG in Cherry Wine, Red Bordeaux, and Umpqua; CBG-A in the distilled biomass was below the detection limit of the instrument. Overall, distillation resulted in slight decrease of total CBG in Cherry Wine and Red Bordeaux and slight increase in the total CBG in Umpqua. The CBG-A and CBG in T&H were both under the detection limit.

    The concentration of CBN in not-distilled biomass was under the detection limit and was 0.041, 0.035, and 0.075% in the distilled biomass of Cherry Wine, Red Bordeaux and Umpqua, respectively, while it was under the detection limit in T&H.

    As expected, distillation resulted in conversion of all THC-A into THC. This has both practical and legal importance; some states limit the concentration of THC in hemp while others limit the concentration of total THC. The concentration of THC in the distilled biomass was 197, 124, and 236% in Cherry Wine, Red Brodeau, and Umpua, relative to their respective concentrations in the not-distilled biomass, respectively. Overall, distillation tended to increase the concentration of total THC in Cherry Wine but decreased it a bit in the rest of the hemp strains (Table 2).

    Scanning electron microscopy (SEM) of the distilled biomass

    Scanning electron microscopy (SEM) analyses revealed that most of the glandular trichomes in the distilled biomass were not disturbed, they were not open (Fig. 3A–E). That suggest a possibility for terpenes evaporation through the epidermal membrane covering the glandular trichomes leaving the cannabinoids in the trichomes. This explained the fact that distillation resulted in terpene extraction while the cannabinoids remained in the distilled material. Furthermore, mechanical harvest and chopping of the T&H biomass resulted in damage of some of the glandular trichomes (Fig. 4A), however, it seems while some of the terpenes may have evaporated, some may have formed a resinoid-like slush with the cannabinoids that did not volatilize. Furthermore, an open sessile gland in T&H after the extraction of the EO (Fig. 4B) indicates similar resinoid-like substance that can be assumed to contain mostly cannabinoids.

    (A) Red Bordeaux extracted flower/leaf parts. (B) Red Bordeaux extracted flower/leaf parts. (C) Red Bordeaux extracted leaf with non-destructed glandular trichomes. (D) Red Bordeaux extracted leaf with non-destructed glandular trichomes and well preserved cystolithic trichomes. (E) Cherry Wine extracted flower/leaf parts.

    (A) T&H non-extracted leaf with part of the sessile gland missing probably due to the mechanical chopping of the biomass, revealing resinoid substance inside that could be a mix of the cannabinoids and some of the terpenes that did not volatilize. (B) T&H Extracted leaf part with part of the sessile gland missing revealing resinoid substance inside that could be the cannabinoids and some of the non-extracted terpenes.

    Discussion

    This study demonstrated that distillation of hemp biomass may extract the terpenes (EO) and leave the cannabinoids in the distilled biomass that can be further extracted. This presents an opportunity for valorization of hemp biomass because of the resulting two high-value products: essential oil (EO) and distilled biomass with largely preserved but altered (into desirable chemical forms) cannabinoids because of the decarboxylation that occurs during the distillation.

    Secondly, the study reveal that the above effects may depend on the specific variety (strain, cultivar) as some CBD was transferred into the EO of one of the tested strains but not in the other three. Still, most of the CBD stayed in the distilled biomass. The extracted biomass did not possess any aroma because the volatile terpenes were extracted. That presents an opportunity for the extracted biomass to be included in various products with targeted designed aroma and flavor of choice.

    The SEM analyses of distilled biomass revealed that the thin layer covering the glands of the glandular trichomes were not open suggesting that terpenes may have moved through this membrane during distillation leaving the cannabinoids in the glands.

    Third, the EO yield, and profile of different strains can differ significantly as a function of the variety (genetics); the major EO constituents can be either the same but in the different concentration gradients, or the 3–5 main EO constituents could be different in different strains. That presents an opportunity to obtain EO with specific composition and subsequently aroma, that would be of interest to the aroma and flavor industries.

    Overall, the EO yield in this study clearly showed that the hemp strains tested in this study were very different from the typical registered industrial hemp varieties listed in the European Union (EU) 22 and in Canada 23 . The EO yield of the hemp strains in this study varied from 0.72 to 1.85% in dried flowers and upper leaves except for the chopped whole plant biomass of T&H which was 0.37%. Recent literature data showed that the EO yield of 8 industrial hemp breeding lines was between 0.06 and 0.14%, while the EO yield of other 8 registered industrial hemp varieties was 0.1–0.2% (mL per 100 g air-dried hemp biomass) 24 . Other studies on industrial hemp have reported EO yield of 0.04–0.3% 3,5,6,9,25,26,27 .

    There are two reasons for the higher EO content of the high-value (high-cannabinoids) hemp used in this study: (1) the four strains in this study were selected in the past from the medical or illicit marijuana strains that have different architecture (phenotype) and genotype than the registered industrial hemp varieties; and (2) three of the strains in this study were established using feminized seed and care was taken to avoid pollination and fertilization of the female flowers, that results in higher density of glandular trichomes (Fig. 1D). The T&H was grown until late, and harvested with a forage chopper that resulted in EO losses (Fig. 4A,B).

    Myrcene and (E)-caryophyllene were two of the main EO constituents in the hemp strains in this study. Myrcene has been reported as a major EO constituent in industrial hemp, ranging from negligible amounts to 25% of the EO 3,5,21,26,27,28,29 . Also, myrcene is found in higher concentrations in hops EO depending on the distillation time 30 . The importance and the use of myrcene, acyclic monoterpene, has been reviewed 31 ; it is a constituent in the EO of many other species such as hop, lemongrass, nutmeg, sage, rosemary and others 31,32 . However, the major raw material for myrcene has been turpentine 31 . Other chemicals such as menthol, geraniol, nerol, linalool can be commercially produced from myrcene, and these products have wide and various applications such as flavor and fragrance agents, in insect repellents, vitamins and also in polymers, pharmaceuticals and surfactants 31 . However, myrcene has been touted as potential carcinogen, and suggested that food and beverages with myrcene should be monitored 32 . Indeed, research has shown myrcene was linked to tumor in the urinary tracts of rodents although no data is available for humans 33 .

    (E)-Caryophyllene, a bicyclic sesquiterpene, has been reported as a constituent of industrial hemp EO ranging from 14 to 33% of the total oil 3,26,28 . (E)-Caryophyllene is a known anti-inflammatory agent, that possesses also analgesic action; it is used as food additive/flavoring agent, has many other biological properties 34,35 . It is found in industrial hemp varieties from 22 to 55% in registered varieties and from 11 to 22% of the EO of breeding lines 36 . (E)-Caryophyllene is considered a dietary cannabinoid and in vivo, it was reported to act as non-psychotropic CB2 receptor ligand in foodstuff 37 . (E)-Caryophyllene is found in the EO of other plant species such as peppermint (Mentha × piperita L.), common basil (Ocimum basilicum L.), oregano (Origanum vulgare L.) black pepper (Piper nigrum L.), and has been known to possess insecticidal, acaricidal, repellent, and antifungal properties 10,35,38 .

    Recent study on 8 registered industrial hemp varieties in Europe (in Serbia, which is approximately at the same latitude as Oregon) has shown the following main EO constituents: (E)-caryophyllene 11–22% and 15.4–29.6%; α-humulene 4.4–7.6% and 5.3–11.9%; caryophyllene oxide 8.6–13.7% 36 . The major EO constituents of the U.S. high-cannabinoid hemp strain that was grown in the close vicinity to the above study in Serbia had different chemical profile, with major constituents as myrcene (9.2 to 12%), (E)-caryophyllene (6.5 to 7.5%), limonene (3.8 to 4.2%), (E)-β-ocimene (5.3 to 5.6%) and α-bisabolol (3.9 to 4.4%) 36 . Therefore, we may postulate that the high-cannabinoid U.S. hemp strains will synthesize and accumulate similar cannabinoids and EO amount and composition in other remote geographic areas at similar latitude.

    Conclusions

    This study elucidated the effect of the steam distillation of four high-cannabinoids hemp strains on changes in the content and compositional profile of cannabinoids. The study demonstrated a simple method for valorization of CBD-hemp through the production of two high-value chemicals; EO and cannabinoids with improved profile through the conversion of CBD-A into CBD, CBC-A into CBC, CBDV-A into CBDV, CBG-A into CBG, and THC-A into THC. In addition, the distilled biomass contained CBN while the non-distilled did not. Distillation improved cannabinoids profile; e.g. the distilled hemp biomass had 3.4 times higher CBD in variety Red Bordeaux, 5.6 times in Cherry Wine, 9 times in variety Umpqua, and 6 times in T&H compared to the original non-distilled samples, respectively. The main 3 EO constituents were similar but in different ratio. The distillation converted most of the THC-A into THC reducing total THC in the process, which carries practical and legal importance because of the rapidly changing legal environment in the U.S. and across the world. Scanning electron microscopy (SEM) analyses revealed that most of the glandular trichomes in the distilled biomass were not disturbed (open); that suggest a possibility for terpenes evaporation through the epidermal membrane covering the glandular trichomes leaving the cannabinoids in the trichomes.

    Methods

    Plant material

    The plant material utilized in this study was from varieties (strains) of cultivated hemp (Cannabis sativa L.) in the United States and this is not an endangered species at risk of extinction. The collection of plant tissue research specimens was acquired (including transportation) conformed scrupulously to procedures and regulations adopted under international legal agreements. In addition, the plant material sampling, transportation, and handling was in compliance with the U.S. federal and Oregon state legislations. Certified and compliant (THC < 0.3% in dry biomass) organically grown CBD-hemp strains (also called chemovars, varieties) Red Bordeaux, Cherry Wine and Umpqua (flowers and some upper leaves) and a T&H strain that included chopped whole-plant biomass were donated by two licensed Oregon hemp producers. The original Certificates of analyses are kept and available from the authors. We are using “strain” to denote non-registered hemp variety (cultivar); this is a common term in the hemp industry in the U.S.

    Distillation of the essential oil (EO)

    Representative subsamples in 3 replicates from each of the four hemp strains were subjected to steam distillation for 240 min in 2-L steam distillation apparatuses as described previously 39 . The first drop of the EO in the separator part of the apparatus was considered the beginning of the distillation. After 240 min non-stop distillation, the power was switched off, the heat source was removed, the EOs were collected in glass vials and stored in a freezer. Later, the EO was separated from the remaining water in the vials, its weight was taken on analytical scale, and transferred to a freezer again until the gas chromatography (GC) analyses could be performed.

    The remaining hemp biomass was removed from the bioflask and spread for drying at T around 30 °C at forced air. After the biomass reached a constant weight, subsamples were generated for cannabinoid extraction.

    Cannabinoid extraction and identification

    Subsamples from non-extracted (original) and extracted biomass was submitted for cannabinoid analyses and characterization to the Columbia Laboratories in Portland, OR (https://www.columbialaboratories.com/), a commercial laboratory that is ISO 17025:2017 accredited, as well as TNI certified. The method of cannabinoid extraction and analyses was JAOAC 2015 V98-6 20 and the instrumentation was HPLC–DAD Agilent 1200 series (Agilent Technologies, Inc. Santa Clara, CA, U.S.A).

    Gas chromatography-mass spectrometry (GC–MS) analyses of the essential oils

    A gas chromatograph Agilent 6890 N equipped with a single quadrupole mass spectrometer 5973 N was used. The stationary phase was a HP-5MS (30 m l. × 0.25 mm i.d., 0.1 mm f.t., Folsom, CA, USA) made up of 5% phenylmethylpolysiloxane; the mobile phase was helium (99.999%) flowing at 1 mL/min. The temperature of the oven was programmed as follows: 60 °C held for 5 min, then increase up to 220 °C at 4 °C/min, finally 11 °C/min up to 280 °C held for 15 min. Once diluted in n-hexane (dilution ratio 1:100) the hemp EO samples were injected (2 μL) through an auto-sampler 7863 (Agilent, Wilmingotn, DE) in the inlet of GC taken at 280 °C using the split mode (split ratio 1:50). Peaks were acquired in full scan mode (29–400 m/z) using the electron impact (EI) mode at 70 eV. Chromatograms were analyzed by the Enhanced Data Analysis program of Agilent G1701DA GC/MSD ChemStation. In addition, the NIST Mass Spectral Search Program for the NIST/EPA/NIH EI was used for peak assignment. Mass spectra (MS) of peaks were compared with those stored in ADAMS 40 (Adams, 2007), NIST 17 and FFNSC3 libraries. The temperature-programmed retention indices (RI) were determined using a homologue mixture of C8-C30 n-alkanes (Merk, Milan, Italy) and computed by the following formula (ref. 41 ):

    where n is the number of carbon atom of the alkane eluting before the unknown peak, tx the retention time of the unknown peak, tn the retention time of the alkane eluting before the unknown peak and tn + 1 the retention time of the alkane eluting after the unknown peak. The combination of the MS overlapping and RI coherence with respect to those reported in the aforementioned libraries was used to assign the peak. Furthermore, for the following compounds the identity was confirmed by comparison with analytical standard: α-pinene, camphene, sabinene, β-pinene, myrcene, p-cymene, limonene, 1,8-cineole, (Z)-β-ocimene, (E)-β-ocimene, γ-terpinene, terpinolene, linalool, borneol, α-terpineol, (E)-caryophyllene, α-humulene, (E)-β-farnesene, (E)-nerolidol, caryophyllene oxide, cannabidiol (Merck). The relative peak area percentages were obtained from the chromatograms without using correction factors. The GC–MS response resulted similar to that of GC-FID as determined previously 21 .

    Scanning electron microscopy (SEM) analysis of hemp flowers, glands, leaves and stems

    The scanning electron microscope (SEM) used in this investigation of hemp biomass extracted and non-extracted samples was an FEI Quanta 600 SEM (ThermoFisher Scientific/FEI, Hillsboro, OR, U.S.A.) at the Microscopy Facility at Oregon State University, (https://emfacility.science.oregonstate.edu/). Samples were placed into a fixative, 1% paraformaldehyde and 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer with pH 7.4, soaked in the fixative for 2 h, rinsed in 0.1 M cacodylate buffer, 15 min each, and dehydrated in acetone (10%, 30%, 50%, 70%, 90%, 95%, 100%), 10–15 min each, followed by critical point drying (two ‘bomb flushes’ at chamber pressure to 5 °C, fill chamber with CO2). The samples were left to vent for 5 min, and then, the procedure was repeated. The dry samples were mounted onto an aluminum SEM stub with double stick carbon tape. Samples were sputter coated with a Cressington (Cressington Scientific Instruments, Watford, U.K.) 108A sputter coater from Ted Pella with Au/Pd, 60/40 mix.

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    Acknowledgements

    We are thankful to the two licensed Oregon hemp producers (Cook Family Farms and Libosoils LLC) for providing certified and compliant hemp material for this study. We thank Ms. Teresa Sawyer for the help with the Scanning Electron Microscopy sample preparation and analyses. Funding was provided by Oregon State University.

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    These authors contributed equally: Valtcho D. Zheljazkov and Filippo Maggi.

    Authors and Affiliations

    Crop and Soil Science Department, Oregon State University, 3050 SW Campus Way, Corvallis, OR, 97331, USA

    Valtcho D. Zheljazkov

    School of Pharmacy, University of Camerino, via Sant’ Agostino 1, 62032, Camerino, Italy

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    V.D.Z. conceived the experiments, V.D.Z and F.M. conducted the experiments, and analysed the results. Authors reviewed the manuscript and approved it for publication.

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    Zheljazkov, V.D., Maggi, F. Valorization of CBD-hemp through distillation to provide essential oil and improved cannabinoids profile. Sci Rep 11, 19890 (2021). https://doi.org/10.1038/s41598-021-99335-4

    Received : 25 April 2021

    Accepted : 23 September 2021

    Published : 06 October 2021

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    Cannabis Distillate: Behind the Making of Pure & Potent Liquid Gold

    Cannabis distillates are the ultra-refined extracts from the cannabis plant found in vape cartridges, edibles, and topical products worldwide. Distillates contain a single cannabinoid in pure and potent oil. Their amber-colored and translucent appearance does not start off that way. A series of extraction and purification processes convert the raw cannabis and hemp plant material into the marijuana distillate found in a significant amount of cannabinoid-based products.

    In a world full of flavorful and aromatic full-spectrum concentrates, why does cannabis distillate seem to be everywhere? Why is this scentless and flavorless extract so coveted among producers? Our cannabis distillate guide breaks down the different distillate types, how they are made, and how they are used for medical and recreational use around the world.

    What Is Cannabis Distillate?

    As a new user, it can get confusing trying to wrap your head around the different types of cannabis extracts available. Simply put, cannabis distillate is a type of cannabis extract that has gone through a distillation process to create a pure product with nearly 100% CBD or THC content. During the distillation process, processors use distillation equipment to separate the targeted compound, particularly THC or CBD, from the solvent, and other compounds.

    Cannabis and hemp are composed of hundreds of individual compounds including cannabinoids, terpenes, flavonoids, and other essential oils. In the end product, boiling techniques remove nearly all of the flavor and aroma that comes from the plant’s terpenes. While terpenes are believed to elevate cannabinoids’ therapeutic potential, they are not always welcome.

    Since all of the wax, lipid, and undesirable plant matter is removed from the extract, distillates take on a translucent look. Its viscous and sticky consistency contains a nearly pure potency reaching up to 98% cannabinoids compared to the slightly lower levels (60 to 80%) of undistilled extracts.

    THC Distillate

    For high tolerance users or medical marijuana patients needing high doses of the inflammation- and pain-fighting tetrahydrocannabinol (THC) compound, THC distillate boasts an impressively high concentration of the intoxicating THC. Its psychotropic and euphoric effects can help treat pain, muscle spasticity, glaucoma, insomnia, low appetite, nausea, and anxiety.

    CBD Distillate

    Cannabidiol (CBD) offers a more subdued and non-intoxicating alternative to the cerebral effects of THC. CBD distillate contains no THC and a nearly pure concentration of CBD. CBD distillate is a powerful extract meant to reap all of cannabis’ and hemp’s wellness benefits without the high. CBD has been shown to help treat seizures, inflammation, pain, nausea, depression, anxiety, and migraines.

    Terpenes and Flavonoids

    Cannabis terpenes are responsible for the unique aroma of each cannabis plant strain. While terpenes are found in minor levels in the cannabis plant compared to cannabinoids, they offer a robust aroma that can fill a room. Flavonoids are found in even lesser amounts and are responsible for the colors in your buds. Removing these compounds helps processors produce a uniform extract that can be flavored afterward.

    What Is the Difference Between Distillate, Oil, and Isolate?

    Cannabis oil goes by so many names, it is hard to keep track. Cannabis distillate always takes on a viscous oil consistency. It is a type of cannabis oil, but not all cannabis oils are distillates. The term distillate is reserved for oils that have undergone a distillation process after the oil has been extracted, winterized, and decarboxylated. Cannabis oils such as live resin, butane hash oil (BHO), Rick Simpson Oil (RSO), or hemp-derived CBD oil are similar but not the same.

    Many people confuse distillate and isolate since they both focus on a single cannabinoid. In fact, isolate is technically a type of distillate since distillation techniques are used to refine the cannabinoid extract. Cannabinoid isolates, however, are completely pure crystalline powder forms of the therapeutic compound. Think of distillate as a less refined but equally powerful extract that elicits potent effects.

    How Is Distillate Made?

    Making cannabis distillate starts with a cannabis or hemp seed and undergoes a range of cultivation, extraction, and post-processing steps to remove the cannabinoids, terpenes, and flavonoids from the biomass (flowers, leaves, and stems). Here is a complete rundown of the supply chain and process used to distill the most valuable cannabis compounds.

    Extraction Process

    Even before the distillation process is initiated, the cannabis plant must undergo multiple steps including being properly dried and cured after harvest. Once dried, the biomass can be extracted using a range of solvents including carbon dioxide, butane, and ethanol. The biomass is packed in a material column, drenched in the solvent, and may be further refined using color remediation techniques before ending up in the collection tank.

    Some processors may perform a winterization on their extracts to remove fats and waxes using ethanol and cold temperatures. In addition, the extract may be decarboxylated to activate the acidic cannabinoids, such as THCA and CBDA, into their parent compounds: CBD and THC.

    In the end, crude oil derived from the initial cannabis extraction process contains a THC or CBD concentration between 60 and 80%. The rest of the oil will be composed of different flavors and aromas (terpenes), vitamins, antioxidants, and other essential oils. After the extraction process, the oil needs to be further purified to become a distillate.

    Distillation Process

    Cannabis distillation equipment varies but the process is very similar among the different distillation methods. Distillation reduces the pressure inside the apparatus to purify the cannabinoid at the lowest possible boiling point. A distillation apparatus heats the cannabis oil to a specific temperature to evaporate the desired cannabinoid from the oil without degrading it and then condensing the cannabinoid vapor back into a liquid.

    Through steam distillation and fractionation techniques, distillation equipment can remove the ethanol, carbon dioxide, or butane solvent and almost everything else besides the cannabinoid through multiple passes.

    Generally, the short exposure to heat during the process reduces the risk of degrading the highly volatile cannabis compounds. In addition, the best equipment creates a thin film of the oil onto the evaporative surface for more uniform heating and evaporation. Compounds with higher boiling points usually fall downward with the force of gravity and agitation into a separate residual collection vessel.

    Distillation Equipment

    Cannabis distillation equipment ranges from small units for small-batch operators to industrial-scale models for larger operations. Running the crude extract through the equipment multiple times helps remove as much of the plant matter, terpenes, and flavonoids as possible. The first “pass” removes volatile solvents, gases, and water while additional passes remove terpenes and flavonoids from the final product.

    Short Path Distillation

    Short path distillation, also known as fractional distillation, is a purification method that uses vacuum pressure to lower the boiling points of the cannabinoids and terpenes. Since lower temperatures are used, the gentle short path distillation can carefully weed out the cannabinoids and terpenes from the end product without damaging them.

    Short path distillation uses slow thermal heating to heat crude oil in a glass flask with a magnetic stirrer. As the temperature slowly rises, extractors can separate fractions of the distillate beginning with the terpenes and solvent. Each fraction is collected in a collection flask. There are usually three, one for terpenes and highly volatile compounds, another for CBD or THC, and the last one for cannabinoids with high boiling points.

    Wiped Film Distillation

    Wiped film distillation is a type of short path distillation. Under a vacuum, the cannabis oil is loaded onto a heated and rotating vertical cylinder. Wipers continuously wipe the extract creating a thin film on the evaporative surface. A chilled condenser in the center of the wipers condenses the THC or CBD vapor. Different collection vessels collect the CBD or THC distillate and any heavier compounds such as chlorophyll, wax, and salts below.

    Rotary Evaporation

    Rotary evaporation techniques use rotary evaporators, also known as roto-vaps, are common in the removal of the solvent from the final product. In a rotary evaporator, the pressure drops using a vacuum pump which reduces the boiling point of the solvent. A rotating distilling flask is filled halfway and heated using a water bath. The distillation flask is rotated creating a thin film of the cannabis concentrate. This increases its surface area to speed up the evaporation rate.

    Falling Film Evaporation

    Falling film evaporators include an evaporator and condenser and use a different boiling point to separate compounds from the cannabis concentrates. Using this method, the oil is drained from above into a heated column and falls downward creating a thin film on the evaporative surface. As the cannabinoids evaporate, they are collected on a chilled condenser. Due to its unique methodology, cannabinoid products with lower viscosity work well under this process.

    How to Use Cannabis Distillates

    THC and CBD distillate can be used in a variety of ways for medicinal and recreational consumption. Its versatility makes it a favorite among extraction companies and consumers. Smoke it, vape it, cook with it, or make soothing lotions and creams infused with THC or CBD. The possibilities are endless. Cannabis distillate can be found in a majority of products sold in retail shops today.

    Dab Rig/Portable Vaporizer

    Cannabis concentrates such as distillates are commonly consumed, or dabbed, with a glass dab rig or electronic nail (e-nail). Dab rigs and e-nails are great for use at home since they can deliver large doses using heated surfaces. E-nails, in particular, can maintain consistent temperatures using a digital controller and power source to perfectly vaporize cannabis oil. E-nails offer the convenience of not having to use a torch and estimate your heat up and cool down times for your nail.

    Portable vaporizers and certain battery-operated vape pens are good for on-the-go consumption. Many vape pen cartridges contain CBD or THC distillate (some with additional flavors) that can be disposed of when finished. Other portable vape pens feature a heating chamber that can be reloaded with a CBD or THC distillate.

    Pipes, Bongs, Joints

    While dabbing distillates is the recommended method of consumption for sky-high potencies, many users may also smoke their distillates to enhance the potency of their dried cannabis flower. Simply add a tiny dollop of your cannabis oil on top of a packed bowl or within/outside your joint for an enhanced effect.

    Edibles

    Cannabis distillates are a favorite ingredient in the making of edible products. Distillates can be infused into your favorite foods or beverages. Add this already decarboxylated oil directly onto your finished meal or use it as an ingredient as you cook. A distillate’s flavorless and odorless form allows you to create edible products that do not have the tell-tale taste and smell of the cannabis plant.

    In addition, you can consume distillate sublingually for faster absorption and onset of effects compared to ingestion. It is recommended to bind the distillate to a carrier fat such as coconut oil, MCT oil, butter or other food-grade oil for better absorption since THC cannabinoids bind to fat. While the extract is already decarboxylated, it still needs help absorbing into the mucous membranes under the tongue. Warm up the mixture, stir until it is dissolved, and it is ready to go.

    Topicals

    No matter what cannabinoid distillate you buy or produce, you can infuse it into a variety of topical products including lotions, creams, and salves. Recipes require cannabis distillates and a carrier oil such as coconut oil along with your favorite essential oils for aroma. The salve infused with cannabinoids can be applied directly to the affected area for localized relief without the high since the cannabinoids cannot reach the blood-brain barrier.

    Why is Distillation Important?

    Through distillation, operators can purchase a greater volume of marijuana trim or low-quality biomass and distill their desired compounds into an ultra-potent liquid.

    Distillates have become the backbone of the marijuana derivatives market. Find them in nearly every product category. Their flavorless and scentless characteristics help create a consistent and repeatable cannabinoid product.

    Those infused gummies and chocolates we all know and love are only possible with a foundation of distillates. And, if you are a fan of aromatic terpene compounds, they can be reintroduced back into the final product.

    Luna Technologies: Automated Cannabis Extraction

    High-quality THC and CBD distillate require an efficient extraction stage to remove as much of the cannabinoids from the cannabis plant. Luna Technologies’ automated extraction system, the IO Extractor, provides processors with a peer-reviewed hydrocarbon solution. Produce clean and pure marijuana distillates from any quality cannabis or hemp biomass using the power of hydrocarbons and automation.

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