Cannabis is grown worldwide, it’s resilient, and it’s in high demand. A demand that isn’t slowing anytime soon. New amendments to the Cannabis Act will make a legal space for edibles and alternative cannabis products in Canada, with an estimated worth of C$2.7 billion annually. And that’s just in our northern-corner of the market.
Cryo Cure’s cannabis and hemp curing machines utilize patent pending freeze drying technology to remove the desired amount of moisture from flower or trim, eliminating many of the risks faced by cultivators and processors. Freezing of marijuana. Following the harvest of cannabis plants, drying and curing are carried out, and this usually takes about a month. Following the successful completion of this process, the cannabis is at the peak of its powers ready to be utilized. The freeze-dry method This process of freeze-drying (lyophilizing) cannabis has been a long-discussed topic but had never been perfected until recently. Cannabis lyophilization involves drying the buds before curing to preserve the flower’s aesthetic and other useful properties and reduce the moisture.
With more legal producers than ever before, the demand for quality cannabis is also increasing. Consumers are no longer settling for sub-par – they want the best. High-quality cannabis starts at the strain-level, requiring investment in every step of the process. This is especially true for post-harvest care.
Cannabis drying and curing are integral in successfully moving plants from harvest to sale. In this article, we’ll differentiate between drying and curing, outlining the pros and cons of each. We’ll look at traditional methods, and touch on innovation in the industry. It’s now possible to save time without sacrificing quality, and Rapid Low-Temperature Dehydration (RLTD) technology is the answer.
The Difference Between Cannabis Drying and Curing
Many growers believe that curing begins at the moment of harvest. If that’s the case, where does drying fit in? In traditional methods, drying and curing are two separate steps, distinguished by humidity, temperature, and time. The method for harvesting is also important, impacting the order of the process.
Ready for Harvest
Cannabis buds are ready for harvest when the majority of the pistils (the small white hairs on the buds) have browned and begun to curl in. Trichomes under magnification can also be used as a tool. They will transform from clear to cloudy when it’s time to harvest.
Once the buds are ready for trimming, there are two main methods: dry trimming and wet trimming. Wet trimming occurs right after harvest when the buds are wet. The moisture makes the buds less fragile, and easier to manage quickly. Dry trimming occurs after drying, but before curing. This method is more challenging and can lead to a loss of product; however, it results in more precisely-manicured buds.
Cannabis Drying the Conventional Way
Regardless of the trimming method, harvested cannabis must be dried immediately to avoid spoilage. Most of the moisture should be removed within the first three days, then slowed to avoid drying out. The product should be kept in a dark room with air circulation, at a temperature range of 60-70°F and humidity between 45-55%.
To ensure even-drying using the conventional method, cannabis branches are hung up or placed on racks. Trimmings are hung upside-down to encourage circulation to smaller branches. In general, traditional hang drying can range from 5-15 days, depending on the size of the buds and the surrounding environment.
The most common way to determine if the drying process is complete is to test the brittleness of the smallest branches. If the small branches snap on bending, and the buds are slightly crisp on the outside, then the plants are ready for curing.
Curing Cannabis
Curing has been a part of food preservation since the beginning of civilization. When most people think of curing, they think of salting meat. For cannabis, however, no salt is needed. Curing can be thought of as an extension of drying, with an altered environment to facilitate plant processes.
The first step in curing depends on whether the plant material was trimmed at harvest. If the branches still require trimming, this must be done first. The buds are then placed into airtight containers, often mason jars about three-quarters full, and sealed.
Cannabinoids are light, heat, and oxygen-sensitive. To prevent mold growth, the buds still need to breathe. In airtight containers, moisture trapped within the buds will be drawn out, creating a humid environment. The ideal humidity is approximately 60-65%, with a below room temperature and complete darkness.
During the first week, the containers must be opened throughout the day to let the buds breathe. In the weeks following, this can be limited to once every few days. Two to three weeks is sufficient for curing but waiting longer is ideal. Four to eight weeks is great for most strains, though some can benefit from even longer.
The Benefits
Drying and curing cannabis has a myriad of benefits. Without drying, the moisture content in buds hinders the smoking experience and can lead to mold contamination. Without curing, the flavour and aroma aren’t given time to properly develop. Much like the ageing of fine wine, cannabis will get better over time under the right conditions.
Here are some of the ways cannabis can be improved post-harvest:
- Improved potency – the biosynthesis of cannabinoids doesn’t stop immediately upon harvesting; under the right conditions, buds will keep converting cannabinoids for increased potency and quality
- Improved sensory experience – terpenes (the molecules responsible for flavour and aroma) are volatile compounds that quickly degrade; curing at low temperatures can help protect these compounds
- Smoother finish – curing helps to get rid of chlorophyll, sugars, and starches within the plant; without this removal, the smoke can be bitter and hard on the throat
- Increased shelf-life – cured cannabis can be stored for up to two years without losing integrity; without drying and curing, the potential for contamination and cannabinoid-loss increases over time.
The Challenges
Mold is the biggest threat to cannabis plants. Humidity is necessary for the curing process, but it also creates the perfect breeding ground for fungi and bacteria. Plant infections such as Botrytis and Penicillium bud rot are common in the industry, in small-scale and industrial-size facilities alike.
Contamination is a threat to production quality and can lead to serious health problems for consumers. For producers, there are additional challenges in using the traditional methods. These include large space requirements for drying rooms, unpleasant odours, and time and labour intensive processing.
Modern Methods
The traditional slow-drying method can be well-suited for small-scale producers. For larger applications, the risk for contamination and the cost of operation scales-up with size. In recent years, alternative methods have been increasing in popularity, in an effort to save time, space, and production quality.
Freeze Drying
Cannabis can be quickly processed with dry-ice through freeze-drying. Temperatures below zero turn water into ice crystals, that can be converted into water vapour using low pressure. A vacuum can then be used to draw out the water vapour, leaving the plant material in its same high-quality state, minus the water.
As dry ice contains no humidity, the risk for mold contamination is reduced. On the other hand, time-consuming rehydration is often required to bring moisture back into the buds for sale. Freezing too early can also prevent the breakdown of undesirable plant compounds, and cause a more unpleasant smoking experience.
Water Curing
Curing with water instead of air is an alternative that enhances the smoke smoothness. In this method, buds are placed into water-filled jars before the drying process. As most of the undesirable plant compounds are water-soluble, the water breaks down these compounds, instead of the plant.
Freeze Drying Marijuana Buds
Sugars, starches, and chlorophyll diffuse into the water, while fat-soluble cannabinoids remain in the plant material. This process is much faster than traditional drying, moving plants from harvest to sale-ready in 5-8 days. While this sounds ideal, there are some challenges with this method.
Certain desirable flavour and aroma compounds in cannabis are water-soluble, and will also diffuse out of the buds. This can reduce the sensory experience in the finished product. The end-product is also less vibrant (as the green chlorophyll has diffused out), and less visually appealing overall.
Vacuum Thermal Energy Technology
Vacuum technology works by reducing pressure within a system, which lowers the boiling point of water and the undesirable compounds in cannabis. This allows for a low-temperature boiling-off, while keeping the desirable colour, cannabinoids, and terpenes in the product.
Vacuum technology pulls moisture from within the buds to the surface, where it can be dried quickly and consistently. Though speed was an enemy to drying and curing in the past, an adapted quick-dry process can actually enhance quality.
Time is the enemy of terpenes. They are volatile compounds that quickly begin to degrade after harvest. Vacuum-assisted drying allows for a faster drying at a lower temperature, where terpenes are conserved. Low-temperature dehydration facilitates drying and curing simultaneously. This eliminates the need for curing, while pampering the plant material.
Cannabis Drying with Dhydra
Dhydra technologies uses a novel adaptation of vacuum technology. With rapid drying time, production cycles are accelerated and energy consumption is reduced. The need for large drying rooms is eliminated, lowering operational costs and increasing potential yield.
Dhydra Technologies has revolutionized cannabis drying and processing by providing the industry with the capability to dry large amount of product in record times. From cut to dry (<10%) in under an hour, Dhydra’s solution can provide the owner with a fully cured product ready for packaging and distribution. Able to process 150lbs or more per hour, Dhydra is changing the cannabis landscape.
RLTD technologymeets and exceeds all of the benefits of traditional drying and curing. It provides a sanitary environment, meeting Food Safety and GMP standards. With an industrial-scale capacity, this technology solves an industry bottleneck.
How it Works
By lowering the pressure, the system creates a vacuum that allows the water in the product to “boil” (water becomes vapour) at room temperature. Dhydra’s Disruptive Technology applies low thermal energy in a strictly controlled manner to generate water vapour without destroying the plants nutrients or other valuable attributes.
By heating the water, rather than the plant nutrients and attributes, Dhydra provides a superior output, including improved flavour and texture. This also allows for maximum oil extraction yields.
One Dhydra advantage is that the system targets energy into tightly defined regions. Rather than standing hot spots, Dhydra controls the travelling waves of energy allowing them to be applied evenly. This allows the energy levels to be matched to the cannabis plants drying ability. Ultimately, in a rapid low thermal processing dehydrator, the energy levels can be controlled throughout the drying process. This prevents the hemp plant from overheating.
Dhydra is the solution for rapid production and remarkable quality – bringing to market an elevated industry standard.
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Pros and cons of freezing marijuana?
Freezing Marijuana Machines
With each passing year more and more ways to utilize cannabis for recreational and medicinal purposes are being discovered. But while the majority are fixated on the numerous benefits cannabis offers they overlook a crucial aspect that can never be overemphasized, the proper storage of marijuana. Cannabis is basically like any other plant and once harvested, if it's not stored properly it would be of no use to anyone. The art of properly storing cannabis is one most people have neglected for far too long and what most don't realize is that properly storing your cannabis is the key to long term success as a cannapreneur, and if you just want to enjoy the recreational benefits of the plant good storage techniques won't just save you a fortune but also enhance your experience and take it to a whole other level.
There are several effective techniques currently being employed in the cannabis world to maximize and lengthen the shelf life of harvested cannabis. Some techniques are better suited for flavor and quality while some are more effective in the maintenance of scent and other features like smell, taste, etc. And of all the storage methods currently available, the method I'll be talking about in here is the act of freezing marijuana. Below I'll drive through what it entails, the pros, cons and a brief summary of other storage procedures you can employ to keep your cannabis at peak condition.
A closer look at the storing of marijuana
The storage of marijuana is a delicate process, to get the best result, you have to maintain the right conditions of temperature, humidity, light, among others. The process of effectively storing cannabis is all about handling the basics, if you can effectively do this you'll find effectively storing cannabis to be a relatively straightforward process. The basics of cannabis storage that you should take note of include:
After cannabis is cured, to maintain it's quality low temperatures should be employed. Although the temperature shouldn't be too low as that could impair the plant's potency. Research suggests 50-60° to be the optimum temperature.
Cannabis loves the dark
Molds and powdery mildew tend to grow on the cannabis in conditions of 77°F or higher.
Freeze Drying Machine
The temperature should be relatively cool as too high temperatures aren't good for the essential oils and texture of the plant.
59%-63% is believed to be the optimal level of humidity required.
Freezing of marijuana
Following the harvest of cannabis plants, drying and curing are carried out, and this usually takes about a month. Following the successful completion of this process, the cannabis is at the peak of its powers ready to be utilized. But in most cases, consumers have more weed than they can use so the only other option available is to store the weed and most people opt for the method of freezing.
The technique of freezing marijuana is carried out by carefully arranging cured buds into airtight containers and placing them in the freezer (the coldest areas). This method is relatively simple and straightforward and can be carried out by anyone. The principle behind this method is that the cold temperatures will preserve the growth of microbes on the plant and also prevent it from aging. And although this method has its advantages a lot of experts advise against it because of its downsides, but what exactly are these disadvantages? Read on to find out the pros and cons of freezing marijuana.
Pros of freezing marijuana
A couple of the pros of this method include:
It is cheap to practice
It doesn't require much technical training or expertise
It delays decarboxylation
It helps prolong the THC compounds in the plant.
It is believed to be the most efficient method of storing cannabis solely for making bubble hash.
Cons of freezing marijuana
It reduces the quality and efficiency of the trichomes in the plant (trichomes produce cannabinoids and terpenes).
Irregular freezing temperatures can cause rot of the cannabis buds either as a result of heat, humidity or fluctuating freezing temperatures.
Once weed becomes freezer-burned recovering the weed at premium quality is an impossible task.
If carried out ineffectively molds and other microbes could grow on the buds rendering them useless.
It renders trichomes brittle and rigid which makes the fall off due to the slightest of touch or contact.
Excessively low temperatures have also been linked with drastically lowering cannabis potency levels.
Taking the pros and cons of this method into consideration you can decide if it's a method you can employ or not. Most experts advise against it as there are other safe and easier methods that can be employed to store your cannabis buds and maintain their quality.
Alternatives to freezing marijuana
Based on successful works of research, the best and most effective way to store cannabis is in airtight jars kept in a cool and dark area. It's paramount that the jar is placed in a place that sunlight can't get to it because it has been shown that UV light causes cannabis degradation which impairs its quality. To get the best results from this technique, the humidity levels in the jar should be closely monitored with a hygrometer to make sure optimum conditions are maintained at all times. Glass jars that repel UV rays can also be used to improve the chances of success.
The majority of people make use of several other methods like refrigeration or storing in plastic containers and cardboard. But research has shown that these methods aren't good for preserving the quality of your cannabis buds. Plastic containers, unlike glass ones that have a neutral charge, have static charges on their surface and this attracts trichomes causing them to stick to the container surface which reduces the potency and overall quality of the cannabis over time.
Bottom Line
The importance of properly storing your cannabis cannot be stressed enough. With the right storage technique, you can maintain the quality and potency of your buds for at least 6 months. Store your buds in dark, frictionless, cool conditions and see it last a long time.