1. Freeze Drying Marijuana Buds
2. Marijuana Drying Tents
3. Freeze Drying Freeze-dryers
4. Cannabis Drying System
5. Freeze Drying Marijuana

Curing weed, by definition, dries it and makes it less suitable for freezing, so if you are planning on freezing your cannabis, you would be best to leave it uncured. Unlike storing weed out of the freezer, it is recommended to use plastic containers precisely because they are totally airtight and hence protect against freezer burn (and also. Aug 04, 2018 The cannabis harvest standard operating procedure to trim and slowly dry flowers first must be followed. A vacuum jar is probably the best choice, or really any storage box without a static charge like plastic can work. Pack with buds and make sure it’s tightly sealed. Now you can safely place your stash in the freezer for long-term storage.

If you are just learning how to cure marijuana, the options are nearly endless, and the results from each technique will vary significantly from the next. Luckily, with rapidly advancing technology, there are always new and exciting methods to dry cannabis, with many of the most recent making leaps and strides as they create user-friendly options that help to preserve more cannabinoids and terpenes than we ever thought possible. One of the latest trends to hit the industry is freeze drying, and it’s making waves as it proves to be one of the best, fastest, and most gentle method of curing cannabis thus far.

What is freeze drying?

Freeze drying is just one way to cure freshly harvested marijuana plant flowers, and it works by drawing all the moisture out of the plant materials slow enough, that the flowers maintain the same size and shape throughout the process. The extremely cold temperatures used can pull out the moisture, which is stored in a water trap, and since it happens so slowly, the water can act as a temporary dissipating skeleton for the bud flowers, which is what helps to maintain the buds form. This is done by using pressure to convert the water into vapors that are easily drawn out using a vacuum.

What are the benefits of freeze drying cannabis?

• Fast working. From the moment you start the machine to the time the buds are ready to be packaged or consumed, the entire process takes only 24 hours to complete.

• Minimal cannabinoid and terpene loss. Freeze drying, when done properly, actually helps to strengthen some of the sought-after components that are produced by cannabis plants like THC, CBD, and terpenes. The average loss of those elements with this process hovers around 1%.

• Faster Trimming. Since the flash freezing makes the outer leaves brittle and crumbly, the process of trimming can be reduced up to 80%. This is also the only method that allows for clean trimming using machines.

• Larger buds. Since the structural integrity of the cannabis bud flowers is held in place by the water as it is drawn from the chamber, the marijuana colas will look the same when they are finished curing, as they did in the moments before they were placed into the dryer. This results in larger, and fluffier buds.

• Preserved colors. With all other methods of drying cannabis, the hue of the plant materials themselves will fade and darken. This can turn the brightest, most colorful buds, into a dull and less than an exciting end product. If there is one thing we know for sure, it’s that consumers appreciate an aesthetically pleasing bud.

• This drying method can be used at any point, including either before or after trimming.

• Natural minerals, vitamins, and oils remain in-tact. This is especially important for consumers who might be eating cannabis flowers.

• Freeze dried buds are easy to break apart for joint rolling or device packing, so there is no preparation needed before customers can use weed if it’s been cured this way.

How to make a freeze dryer for weed (and use it)

Figuring out how to make a freeze dryer for cannabis can be full of trial and error, but once you get the seals in place, and have a working machine, the rest of your job will be easy as pie. You can use many different types of materials in place of those that are listed here, as long as they can hold up to the pressure and cold for an extended period of time.

You will need:

• 2 2-quart vacuum chambers
• 1 2 gallon-stainless steel pot with lid
• 1 ¼ inch flare union
• 1 ⅝ barb splicer
• 3 meters (or less) of ⅝ inch tubing with braided reinforcement
• 4 large 1-inch thick Styrofoam sheets
• Glue (school glue or any spray adhesive)
• 1 cooler filled with dry ice slabs
• Denatured Ethanol (approximately 1-liter)
• 1 high-quality vacuum gauge
• 1 2-stage rotary vane vacuum pump
• 1 carpenters knife
• 1 package of JB Weld
• 1 small hose clamp

Instructions

1. The first thing that you will need to do is create a protective barrier that can line the cooking pot to help keep it cold. To do this, measure out squares that allow for 3-4 inches of Styrofoam on each side, and then trace out the base of the pot to make them into sleeves.
2. Feed them one by one onto the bottom of the cooking pot, until it is entirely covered. Then cut three more squares without holes to act as a base. This will protect the surface that the freeze dryer is set on.
3. Double check the sleeves fit, and once you are confident the pot will fit comfortably, you can glue all the pieces together. This helps as it creates a seal that will keep the frigid temperatures in.
4. Now cut one more piece of Styrofoam by measuring the size of the vacuum chamber inside of an outer circle that fits the 2-gallon pot. It will help to hold the chamber in place, as well as to keep the cold air inside.
5. Feed the chamber sleeve over the top of it and set it into the pot. Now you can measure and remove a small square from the sleeve, that will allow you to drop in dry ice as needed.
6. Attach the union to one of the chambers and use it to hook up the vacuum gauge.
7. Remove the vacuum gauge that came with the second chamber and use a ⅝ bit to widen the hole enough to fit the splicer.
8. Use the JB Weld to secure the splicer in the hole.
9. Allow the JB Weld sufficient time to dry completely, and then hook up the rubber hose by sliding it over the splicer and clamping it into place.
10. Now you will want to make a few more insulating sleeves for the chamber that you have installed a gauge on, just like you did with the pot, including three layers for a base.
11. Once you are finished gluing the last of the insulation pieces together, it is time to put your freeze dryer to good use.
12. Fill the 2-gallon cooking pot approximately ¾ of the way with denatured alcohol and drop several pieces of dry ice in through the window. Once you begin adding dry ice, the alcohol will bubble for a few minutes, but as the temperature of the liquid drops that will slow down so that you can safely add more throughout the process.
13. Place the cannabis plant materials inside of the chamber that is sitting in the cooking pot and seal the lid.
14. Turn on the vacuum pump, and watch the magic happen. You will need to add additional dry ice at least every two hours over the next 24 to maintain the ideal temperature.
15. After 24 hours, it’s time to shut everything down and assess the results. If you have anything other than perfectly cured bud flowers, then you likely have a leak somewhere in the system. At that point, you can go over all the connections and joints with some JB weld until the issue is resolved and try again.

How to store marijuana after it has been freeze dried

Once you have freeze dried your cannabis, if you haven’t already, it will need to be trimmed before it can be tucked away safely into storage. Since buds that have been dried with this method end up firmer than others, you might think that it can be stored in a baggie, but we highly recommend against that. Instead, you should invest in some high-quality resealable glass jars that will keep the marijuana from bouncing around and turning into powder.

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.

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.

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

Freeze Drying Marijuana Buds

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

Marijuana Drying Tents

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.

Freeze Drying Freeze-dryers

Dhydra is the solution for rapid production and remarkable quality – bringing to market an elevated industry standard.

Cannabis Drying System

References:

Freeze Drying Marijuana

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