There is a long-felt need in the Cannabis industry for an effective means of (1) providing a Cannabis concentrate product that can be dispensed with a semi-automated filler; (2) providing a batch product that is consistent from jar to jar due to the ability to homogenize the mixture prior to dispensing; (3) providing a product that can be packaged in hours instead of days; and (4) high batch to batch consistency.
This summary is provided to introduce a selection of concepts that are further described below in the Detailed Description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
The present invention relates to the manufacture of a Cannabis concentrate from dried, destemmed, and optionally ground Cannabis obtained via a closed-loop extraction using hydrocarbons, such as propane or butane. Another aspect of the present invention relates to a process of exposing dried, destemmed, and optionally ground Cannabis obtained via sequential CO2 and closed-loop extraction using hydrocarbons, such as propane or butane. Another aspect of the present invention relates to exposing Cannabis biomass to a polar solvent, filtering, then evaporating the solvent to form an extract. The solvents are then removed, for instance using heat and vacuum. Another aspect of the invention relates to compositions, such as Cannabis concentrates, that can be obtained through the process described.
According to at least one embodiment, the present invention relates to methods for production of a Cannabis concentrate (sugar wax) using Cannabis biomass (THCA crystals) obtained from a “PiggyBack extraction” of closed-loop extraction process. The THCA crystals from the PiggyBack process are dissolved in a polar solvent, and then mixed with in-house terpenes (IHT) (terpenes extracted from Cannabis or another plant/fruit/or other natural or synthetic source in the form of isolates or blends) to contain up to 8% w/w IHT. The mixture can be homogenized using a high shear mixer and then dispensed with a semi automated machine. The volatiles are then removed by heating the mixture at a temperature of at least 40° C. for a time period sufficient to purge the volatiles to a concentration below at least 5000 ppm, and according to certain embodiments below 2500 ppm, and in certain embodiments below 1000 ppm.
The resulting sugar wax product provides a Cannabis concentrate product that can be dispensed with a semi-automated vape filling robot, provides a batch product that is consistent from jar to jar in a fraction of the time it takes to hand weigh the product.
The present invention describes a novel method for the production of Cannabis concentrate product (sugar wax) utilizing a raw material produced from the applicant's proprietary piggy-back extraction process described in U.S. Pat. No. 11,697,078 (U.S. Ser. No. 17/484,718) (“the '078 patent” and alternatively referred to herein as “PiggyBack” extraction process) filed Sep. 24, 2021, the disclosure of which is hereby specifically incorporated by reference in its entirety.
The “PiggyBack” extraction process, or closed-loop extraction process, described in the '078 patent requires harvesting of Cannabis plants, drying of biomass through either air-drying or by low temperature vacuum oven, destemming (optional, but recommended for efficiency), stripping terpenes and other cannabinoid or non-cannabinoid impurities with subcritical &/or supercritical CO2, extraction of high purity cannabinoids/cannabinoid acids (up to 90% purity) with liquified hydrocarbon, for instance using propane or butane.
The crystalline cannabinoid acids contained may be used directly from the extractor, decarboxylated to yield neutral cannabinoids, esterified, oxidized, reduced, isomerized, or otherwise transformed either chemically, thermally or photochemically into alternative cannabinoids\cannabinoid acids of interest. Because the method described herein does not require decarboxylation to achieve high extraction yields (particularly necessary for supercritical CO2 extraction) and decarboxylation can occur with purified crystalline extracts (i.e. after extraction), the space utilization in a vacuum oven can be increased dramatically (ca. 5-fold compared to biomass containing 20% cannabinoid acid; 10-fold with 10% cannabinoid acid biomass) thus enhancing throughput. Decarboxylation of the highly pure extract also has the advantage of better heat transfer than decarboxylation within the biomass. Additionally, because the rate of decarboxylation can be greatly affected by the presence of other chemical species within the biomass (through matrix effects) and these species are not present in the extracted cannabinoid acids, shorter times and lower temperatures are permissible for decarboxylation (i.e. higher yields can be obtained). The purity of the crystalline material obtained from the extract is sufficiently high that no further processing is necessary to obtain a usable distillate with greater than 90% purity. Thus, precipitation of fats, waxes and other phytochemical impurities followed by distillation is not required resulting in a significant cost savings due to lower initial capital expense, shorter operations time and avoidance of massive losses in yield due to one or multiple distillations or recrystallizations to achieve the desired purity. Throughput can be roughly doubled by removing the time-consuming step of distillation. Furthermore, the purification with subcritical and/or supercritical CO2 yields a mixture of terpenes and neutral cannabinoids that can be processed by standard means and sold.
In at least one embodiment, the impurities can be stripped out using other solvents (such as, for instance, fluorinated hydrocarbons like tetrafluoroethylene or slightly acidic/neutral water) that are selective to dissolution of terpenes and/or neutral cannabinoids so long as dissolution of cannabinoid acids is limited. Alternatively, solvents that are capable of solubilizing cannabinoid acids, but have a slower rate of solubilization relative to solubilization of impurities may be employed with special emphasis being placed on the time component of the stripping extraction. The parameters for subcritical and/or supercritical CO2 stripping of impurities can be adjusted as needed to obtain either high yields with high purities of neutral cannabinoids and cannabinoid acids or under harsher conditions over longer periods of time to strip neutral cannabinoids like CBG, CBD, or THC from the biomass yielding only high purity THCA upon secondary extraction.
The cannabinoids obtained in the stripping process can be recovered through standard precipitation→distillation methods. Liquified hydrocarbon extraction of the stripped biomass yields an extract with composition consistent with the pre-extraction (stripping) parameters. For instance, a subcritical CO2 stripping primarily removes terpenes from the biomass while a combination of subcritical and supercritical CO2 stripping also removes neutral cannabinoids. The former resulting extract from these scenarios contains a mixture of neutral cannabinoids with total purities (THC+THCA) of up to 85% and the latter yielding an extract containing primarily cannabinoid acids with average purities of 90% for THCA (the remaining constituents being primarily CBGA and THC).
The PiggyBack extraction process is illustrated in
Crude PiggyBack extract is solubilized in a polar solvent, preferably ethanol, in a mixing vessel. Shear mixing is required to ensure homogeneity as hard clumps of THCA crystals can form during the extraction process. Ethanol concentrations of at least 20% w/w in the final formulation were sufficient for cystal dissaloution and homogenization. and semi-automated packaging.
In accordance with the invention, the biomass obtained from the PiggyBack extraction process is first winterized. Winterization is the process of removing compounds, such as fats, lipids, waxes, and chlorophyll, from the crude oil before the distillation process. Winterization involves taking a nonpolar substance, i.e. crude oil, and dissolving it in a polar solvent, such as ethanol, at sub-zero temperatures to create a miscella mixture. Any polar solvent will work for this purpose, but ethanol is preferred. The ethanol should be added in a ratio of about 1:10 to 1:3 ethanol to biomass. In one embodiment, the ethanol is added in an amount such that the concentration does not exceed 5000 ppm, or 0.50 w/w %.
Once the ethanol is added to the biomass, the temperature of the mixture should be maintained at −20° C. or lower in a chiller or freezer for a time period of at least 24 hours to coagulate the undesirable ingredients. Once sufficiently coagulated, the miscella is filtered, preferably with the assistance of a vacuum, during which the ingredients should be kept cool to assure the lipids and waxes do not dissolve back into solution. Once filtered, the winterized PiggyBack extract (WPE) is collected and at least some of the ethanol is evaporated from the WPE.
In-house terpenes (IHT)(terpenes extracted from Cannabis or another plant/fruit/or other natural or synthetic source in the form of isolates or blends) are then added to the THCA mixture to contain up to 10% w/w IHT. The crystals are preferably mixed with at least 3% IHT, with 7-10% w/w IHT being preferred. It has been determined that, in terms of appearance, formulations containing 5, 7, and 10% w/w IHT were most acceptable, with about 10% IHT being preferred by patients in terms of taste. Formulations with at least 5% w/w IHT are preferred in terms of consistencies, i.e. the formulation being soft and crystalline enough to manipulate and transfer.
According to at least one embodiment, the slurry is then mixed with up to 25% ethanol. The slurry is preferably mixed with at least 15% ethanol, with 20% ethanol being preferred. According to at least one embodiment the mixture is then packaged, preferably using an apparatus such as the hopper and valve assembly shown in
The mixture is then heated to a temperature of between about 40-80° C. (55-65° C. preferred) and placed under an incrementally increased vacuum for a time period of at least 8 hours for volatiles purge, and in certain embodiments preferably to a volatiles threshold of below about 0.36%. In one embodiment, a seed crystal is included in the mixture to facilitate recrystallization. The mixture is typically heated for at least an hour and up to 15 hours, and preferably with a vacuum, typically at psi of −1 to −14 psi (full vacuum), with about −10 to −14 psi being preferred. In one embodiment, the mixture is headed for about 12-18 hours. It has also been determined that the vacuum should not be pulled away too aggressively at the start of purging, but should ideally be pulled in 1 psi increments every 20-30 minutes starting at −10 psi to prevent rapid evaporation of the solvent from individual jars. The average post-purge mass typically ranges from about 3-10% RPD. As persons of ordinary skill in the art will understand, the term “purged” refers generally to the removal of a solvent via vacuum and/or heat.
According to at least one embodiment, the sugar wax product is then packaged, preferably using an apparatus such as the modified hopper and valve assembly shown in
The following examples are offered to illustrate but not limit the invention. Thus, it is presented with the understanding that various formulation modifications as well as method of delivery modifications may be made and still are within the spirit of the invention.
Biomass. All extract used in these experiments was obtained from biomass with 210730EOG-2 and 210916EOG batch ID's. Biomass was weighed at the time of harvest and hung to dry per GRO-0025. After four days of drying, biomass was destemmed and allowed to air dry until the moisture content was <10% (w/w) per PRO-0014 before further extraction and processing.
THCA crystals. All THCA crystals were obtained via PiggyBack extraction (sequential subcritical carbon dioxide (CO2), then propane extraction) of dried, destemmed biomass per PRO-0033 and PRO-0192, respectively.
Winterized PiggyBack extract (WPE). All WPE was obtained by winterizing THCA crystals with ethanol (EtOH) at a 1:5 mass ratio, filtering, and evaporating EtOH down to 50 mbar per PRO-0048. The amount of EtOH remaining in the WPE after evaporation was estimated to be 18 (±2) % (w/w), which will need to be removed during the vacuum purge objective.
Raw materials, equipment, and consumables. All raw materials, equipment and consumables needed to complete the methods are given in Tables 1-3.
Volatiles analysis on the moisture balance. Triplicate 1.00 g (±0.05 g) samples of THCA crystals were spiked with either 0, 2.5, 5, 10, 15, or 50 μL of EtOH and analyzed on the moisture balance. The actual volatiles content expressed as [EtOH] (ppm) was plotted vs the expected values to determine if the results were 1) linear and 2) in agreement with the expected values. This experiment was performed to determine if the moisture balance could be used to reliably quantify the amount of volatiles (i.e., EtOH) in a formulation before and after vacuum purging. The slope of the line for the actual vs expected [EtOH] (ppm) was used to set a threshold volatiles content never to exceed in a formulation such that it does not exceed 5000 ppm, or 0.50 w/w %, which is Iowa's residual EtOH specification for a vaporizable product.
Lab scale formulations. A bulk ˜30 g amount of WPE was analyzed in triplicate on the moisture balance to determine the percent volatiles (i.e., % volatiles) and % solids in the starting raw material. WPE samples (1.25 g (±0.10 g)) were aliquoted and mixed with in-house terpenes (IHT) such that the final formulations contained 0, 1, 3, 5, 7 and 10% (w/w) IHT. Each formulation was warmed up in the hot box at 60° C. for 30 min before vortexing for 30 sec, or until the formulation looked consistent throughout. The amount of IHT added was determined based on the mass of solids (g) in the formulation from the % solids calculation (Eq. 1). The formulations containing 0, 1, and 3% IHT were purged in the vacuum oven at 60° C. for 2-, 4-, and 8-h increments. The formulations containing 5, 7, and 10% IHT were purged in the vacuum oven at 60° C. for 8 h. The amount of volatiles in each formulation was determined on the moisture balance after purging to see if they were below the threshold (see section Volatiles analysis on the moisture balance). Each formulation was then tested by a panel of three cardholders to determine their level of acceptability in the following categories: appearance, taste, effect, and consistency. Taste was particularly important to characterize as residual EtOH is the number one concern with this formulation, and the product cannot taste like EtOH even if the volatile content is beneath the threshold. Cardholders were asked to rate their level of agreement with the following statement: “The [category] of the formulation was acceptable.” Acceptability scores were assigned according to the scale in Table 4. Each category must receive an average score of 4 or better to be deemed acceptable. The formulation with the highest score was chosen for pilot experimentation.
% Solids=100%−% Volatiles Equation 1.
Pilot scale mixing. A 93 g sample of WPE evaporated down to 50 mbar on the rotovap was analyzed in triplicate on the moisture balance to determine the percentage volatiles in the raw material. The percent solids and mass of solids (g) in the formulation was determined from these measurements. IHT was then added to the WPE such that the final formulation was 90% solids and 10% IHT (w/w). The formulation was mixed on an overhead mixer at 300 rpm for 15 min and then placed in the vacuum oven at 50° C. and atmospheric pressure until it was ready to be packaged into individual jars.
Semi-automated dispensing on the vape filler. The final appearance of the packaging apparatus is shown in
The actuating time was adjusted until the dispensed mass was between 1.20-1.25 g for three consecutive measurements to calibrate the apparatus prior to packaging the pilot scale batch. Individual 9 mL jars were then filled using the purge button on the vape filler until the formulation ran out. An empty mass and final mass of each jar were taken to track the mass loss of each jar during purging in the vacuum oven. The formulation collected during calibration of the packaging apparatus was loaded back into the bowl reducer towards the end of the pilot batch to reduce product loss. Individual components of the packaging apparatus were also weighed before and after packaging to determine the amount of product loss we can expect in a full-scale production batch.
After packaging, four random jars were pulled and analyzed on the moisture balance to determine the baseline amount of volatiles in the formulation. This value was compared to the baseline volatiles obtained on the lab scale to check for formulation consistency during scale up. These jars were then tested in triplicate for potency per QCU-0106 and QCU-0267 to determine if the total THC before purging was consistent during scale up as well.
Amongst the remaining jars, 5-10 mg of THCA crystals from batch ID 210825EOG-A were added to ten jars to serve as a “seed” crystal prior to recrystallization. Both sets of jars (with and without a seed crystal) were placed in the freezer (−10° C.) for 14 h to facilitate the precipitation of THCA from the formulation. The goal of adding a seed crystal to a select number of jars was to determine if this would result in a more acceptable final product appearance and consistency after vacuum purging.
Vacuum purging on the pilot scale. Each jar was then loaded uncapped into the vacuum oven. The jars were spaced evenly throughout the oven and on all three shelves. The oven was set to 60° C. and vacuum was pulled in 1 psi increments every 20-30 min starting at −10 psi to −14 psi, or full vacuum. Vacuum was kept static throughout this objective. After 9 h and 15.5 h in the vacuum oven three sets of jars with and without a seed crystal were removed and analyzed for volatiles and potency. All jars with a seed crystal were removed from the vacuum oven after 15.5 h after determining that each jar was beneath the threshold of volatiles and had an acceptable appearance and consistency. The remaining jars without a seed crystal were purged for an additional 24 h (40 h total). After 40 h, the remaining 46 jars were then seeded with −5 mg of THCA crystals, placed in the freezer for an additional 14 h and purged for an additional 7 h at 60° C. and full vacuum (total purge time 47 h).
At the conclusion of the pilot experiment, 6×1 g jars with a seed crystal removed at 15.5 h and 6×1 g jars that were purged for 47 h were set aside for sensory testing per the template provided in Attachment 2. The jar-to-jar variation per patient per category were assessed to look for statistical differences in overall final product acceptability when a seed crystal was added prior to recrystallization. An additional 42×1 g jars were set aside for room temperature and refrigerated stability testing per QCU-017.
Volatiles analysis on the moisture balance. Measuring a known amount of EtOH that was spiked onto THCA crystals using the moisture balance showed linearity from 0-10 μL, or 0-˜10,000 ppm, of EtOH as shown in
Lab scale formulations. Vacuum purge conditions were initially defined using the lab scale formulations prepared with 0, 1, and 3% IHT (w/w). WPE exhibited a baseline volatiles of 2.0 (±1.2) % as shown in
The scores for the appearance of each formulation are shown in
The taste of each lab scale formulation is shown in
The effect of each lab scale formulation was deemed acceptable regardless of formulation ratio (
The consistency of each lab scale formulation closely mirrored the appearance acceptability as shown in
Based on all sensory data and vacuum purge data gathered on the lab scale formulations, the final formulation ratio of 90% WPE/10% IHT and vacuum purge conditions of 8 hours at 60° C. under gradual static vacuum from −10 psi to −14 psi (i.e., full vacuum) were chosen as the conditions to pilot.
Pilot scale mixing and semi-automated dispensing. A 103 g formulation consisting of ˜90% WPE and 10% IHT (w/w) was successfully mixed and packaged on the apparatus shown in
The pre-purge volatiles content in the pilot batch and lab scale batches are shown in
The potencies (w/w %) of THC, THCA and total THC (Total THC %=THC %+THCA %*0.877) for the lab scale and pilot scale formulations prior to purging in the vacuum oven are shown in
Vacuum purging on the pilot scale. The first round of pilot scale vacuum purging was unsuccessful and resulted in a final product that was inconsistent in both appearance and consistency as shown in
After 15.5 hours of purging, vacuum was broken again to check the progress of the appearance and % volatiles of the jars with and without a seed crystal. The appearance of the jars without a seed crystal was still unacceptable, although it was noted that small amounts of precipitate had begun forming in some of the jars (
After 15.5 h of purging, all jars with a seed crystal were removed from the vacuum oven because their appearance and % volatiles were acceptable. The jars without a seed crystal were loaded back into the vacuum oven and purged for an additional 24 h for a total of 40 h of purging. After 9 h under vacuum, it was hypothesized that the absence of a seed crystal slowed the drying of these formulations (
Seeding the remaining jars after 40 h of purging did not produce an identical appearance to what we saw with the seeded jars at 15.5 h of purging (
Potency analysis of the sugar wax. THC %, THCA %, and total THC % for the lab scale and pilot scale formulations are shown in
Sensory testing of the sugar wax. The acceptability of the appearance of the pilot scale formulation is shown in
The acceptability of the taste of the pilot scale formulation is shown in
The acceptability of the effect of the pilot scale formulation is shown in
The acceptability of the consistency of the pilot scale formulation is shown in
Total acceptability of the pilot scale formulation is shown in
Stability testing of the sugar wax. Refrigerated and room temperature stability testing could not be performed on the sugar wax from the pilot scale batch because its duration in the vacuum oven decarboxylated more THCA to THC than what will be seen in a large-scale production batch. The appearance and consistency of the remaining jars was also different than our goal, so there would be no way to determine how these qualities change over time. Stability testing should proceed with the first large-scale production batch per the steps described in the Methods (see section Vacuum purging on the pilot scale).
Of the 67 packaged pilot scale units prepared, the average post-surge mass was 1.0 (0.1) or a RPD of 10%, indicating the reproducibility of the post-purge masses regardless of vacuum purge duration or the presence of a seed crystal. In addition, evaluating just the jars packaged under the ideal conditions for a full production batch, the average post-purge mass was even more precise at 1.01 (±0.03) g, or a RPD of 3%. The total mass loss after vacuum purging at 15.5 h and 47 h was 18 (±1) % and 19.4 (±0.8) %, respectively, suggesting sufficient removal of EtOH from the starting material (18±2%). All masses from the pilot batch can be found in Attachment 3. The data collected on both the lab and pilot scale experiments indicate that the Sugar Wax formulation is ready for scale up to a full production batch (˜900 g) under the following conditions: 1) the formulation consists of 90% THCA crystals and 10% IHT (w/w), 2) the formulation gets packaged with the apparatus shown in
It should be appreciated that minor dosage and formulation modifications of the composition and the ranges expressed herein may be made and still come within the scope and spirit of the present invention.
Having described the invention with reference to particular compositions, theories of effectiveness, and the like, it will be apparent to those of skill in the art that it is not intended that the invention be limited by such illustrative embodiments or mechanisms, and that modifications can be made without departing from the scope or spirit of the invention, as defined by the appended claims. It is intended that all such obvious modifications and variations be included within the scope of the present invention as defined in the appended claims. The claims are meant to cover the claimed components and steps in any sequence which is effective to meet the objectives there intended, unless the context specifically indicates to the contrary.
The foregoing description has been presented for the purposes of illustration and description. It is not intended to be an exhaustive list or limit the invention to the precise forms disclosed. It is contemplated that other alternative processes and methods obvious to those skilled in the art are considered included in the invention. The description is merely examples of embodiments. It is understood that any other modifications, substitutions, and/or additions may be made, which are within the intended spirit and scope of the disclosure. From the foregoing, it can be seen that the exemplary aspects of the disclosure accomplishes at least all of the intended objectives.
The present application claims the benefit of priority to U.S. Provisional Patent Application No. 63/389,704, entitled “Process for Preparing Cannabis Sugar Wax Concentrate and Related Composition and Methods,” filed Jul. 15, 2022, the entire disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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63389704 | Jul 2022 | US |