Decarboxylation (decarb) 101: Basic understanding and at home method comparison

By Troy Ivan

Like most people, when I first heard ‘DECARBOXYLATION’ I had no idea what it meant and the word itself confused me, but the sound of science grabbed my attention, I had to know more.  I was relieved to learn a short form of the big word existed and is commonly referred to as ‘decarb’.  The more I researched the more confusing the concept and process became. Everyone had different stories, experiences, opinions and references to a wide verity of conflicting recommended temperature and time combinations.  Some people even claimed decarbing was a myth and completely unnecessary.  The vast majority of available information was unorganized and unreliable, stoking my motivation to work on this experiment to find some clarity on different decarb methods.  There are far too many methods and time/temp combinations for me to cover all, so I chose to compare a few of the most easy to perform in a normal home kitchen.  Before we get too far ahead of ourselves, let’s build a better familiarity with the different important aspects and implications of performing decarb.


Being familiar with the basic science involved with decarboxylation can be very helpful in sorting through all the internet noise surrounding the topic.  Let’s start at the beginning with the natural form of tetrahydrocannabinol (THC) that develops in the trichomes of the cannabis plant as it grows and matures, THC-A.  You will hear many people refer to THC-A as the “acid form of THC”, meaning it has an extra carboxyl group that differentiates it from THC.  Notice that the word ‘carboxyl’ is the root of “decarboxylation”, which simply means to remove the carbolic acid group.  When the carboxyl group breaks away carbon dioxide (CO2) is given off and the molecular mass of THC-A reduces by about 12% becoming the smaller molecule known as THC. This size relationship can be seen in one of the most common equations used for measuring total potential THC in a cannabis sample [THCtotal = (THCA x 0.877) + THC].

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The change from THC-A to THC is a natural process that begins immediately when the plant is harvested and continues very slowly over years depending on how well the cannabis is prepared and stored.  The process can be accelerated by soaking cannabis in a solvent like ethanol, completing the conversion in just 6-8 months, or hyper-accelerated with the application of heat.  Decarb is influenced by three specific variables: temperature, time, and environment.  Changing any one of the three variables will affect the extent of decarb achieved.  By applying varying degrees of heat you can fully decarb cannabis at different rates. Low heat will take longer, high heat works faster, and the temperatures used for smoking or vaping cause instantaneous conversion. As time passes decarb continues, so with the comparison of any two periods of time, with everything else equal, the longer time period will always result in a higher degree of decarb. Environment is a more opaque and less concise consideration but very important.  Open air, ambient temperature, and exposure to sunlight will cause oxidation, conversion and degradation of both THC-A and THC.  The environmental influence on the cannabis I used in this exercise had already taken place prior to it coming into my possession, making it a fixed variable across all the samples used for each method.  Therefore, I will treat environment as a constant and remove it from the discussion in comparing the different methods in this exercise and concentrate on temperature and time.

Everyday I see people seriously obsessing over the simple science of decarbing and meticulously analyzing every factor for fear of ruining their cannabis if they make an error.  Simple decarb questions in some groups often break out into internet brawls.  If you take a step back and think about it, you can see there is very little precision happening in your kitchen compared to a lab, so it might be best to treat the decarb process less like a lab procedure and more like a kitchen activity. If the starting material came from a source other than your own grow, you have no real idea how it was stored, how long it’s been out, how much sunlight it’s taken on, and the real state of decarb that’s already taken place (environment factor).  Even if you did grow, cure, and store it yourself, in most cases it would be difficult to know precisely.  Furthermore, controlling the temperature of your appliances, especially cheap appliances, will be far from laboratory specifications but they will be good enough to do what we need them to.  So, my general advice is to relax a little bit, take what I’ve written here under advisement, give it a little thought, take your best shot, believe in chaos theory, stay lifted, and move on.


The quality of terpenes and amount of decarb present in the cannabis you consume are both dependent on the same three variables (temp, time, environment) but are at odds and inversely correlated.  Meaning, any factor that furthers decarb comes at the expense terpenes.  The loss of terpenes during decarb is a concern for most people, but it’s not an easy problem to solve since anything that facilitates decarb degrades terpene quality.  Maintaining low processing temperatures can help preserve some of the most volatile terpenes to a minor degree and decarbing with a containment that can trap them can also provide a small degree of salvation, but for the most part you have to accept the fact that when you choose to decarb you will have substantial terpene conversion and loss.  Luckily, one of the most exciting recent developments in the cannabis industry is the availability of isolated terpenes and terpene profiles that can be reintroduced to a decarbed concentrate to make up for any loss and in some cases make the concentrate better than it would have been originally.

Another cost of decarb that causes concern is the conversion of THC to CBN.  Only a small amount of elevated CBN can cause a difference in the psychoactive effects of cannabis.  CBN conversion takes a bit of effort, and you have to over process a decarb by a decent margin, but the good news is, even if it happens it’s not the end of the world.  People often mistake the effects of CBN to an elevated degree of being ‘high’, when in reality it’s not more ‘high’ but more sedated.  In fact, many people who need a very strong ‘chill’ factor or heavy sleep aid seek the help of the CBN component.

This study is incredibly well done and interesting in many ways, if you have a chance to chew on it a bit I highly recommend it.  It discusses the science of many aspects of the process, including nullification of CBN development under vacuum, temp/time combinations for both THC and CBD, and other interesting stuff.  Decarboxylation Study of Acidic Cannabinoids: A Novel Approach Using Ultra-High-Performance Supercritical Fluid Chromatography/Photodiode Array-Mass Spectrometry.


To determine if decarbing is necessary for your intended use and needs decide if you require the benefits of THC-A, THC, or both.  To begin exploring this, let’s look at the difference in the psychotropic effects and the potential benefits of using THC-A and THC.  The most obvious difference between the two is that THC-A does not induce psychotropic effects, the feeling of being “high”, while THC does when ingested orally or inhaled.  THC-A has become very important as an anticonvulsive, controlling and stopping many forms of seizures, anti-inflammation, pain relief, nausea, depression, overall well-being, and has shown positive signs in the treatment of prostate-cancer. It can do all of this without making people feel high.

On the other hand, THC has strong psychotropic effects that some people love and others have difficulty with.  The difference in psychotropic effect is a result of the smaller relative molecular size of THC compared to THC-A.  The smaller molecular size allows THC to pass through the blood-brain barrier and attach to the cannabinoid receptors in the brain, creating the ‘high.’  The smaller THC molecule has been demonstrated to have an increased ability to kill cancer cells, work as an anticonvulsant, bronchodilator, appetite stimulant, strong pain reliever, sooth nausea, help with PTSD, induces sleep when nothing else works, along with a number other general health benefits.

The choice between using THC-A or THC is generally pretty clear-cut, as already discussed, but a couple of brief comments on how that choice relates to the various modes of consumption like oral ingestion, suppositories, topicals, smoking and vaping might be helpful. The decision to decarb for oral ingestion typically hinges on two considerations, desired benefits and one’s tolerance for psychotropic effects. Suppositories are typically understood to have no psychotropic effects if used properly so either THC-A or THC can be used.  Having said that, suppository effectiveness is hotly debated and I would recommend reading my post “The Cannabis Oil Suppository Debate: Personal Testing & Results”for more information.  Topicals are not directly ingested into the body orally nor through the lungs so either THC-A or THC can be used, without psychotropic effects.

When it comes to smoking or vaping there’s an interesting consideration concerning conversion efficiency and bioavailability.  In most cases, the rule of thumb for cannabis that will be smoked or vaped is that decarbing prior to consuming is not necessary because it occurs automatically when combusted or vaped.  With combustion and smoking of flower high temps are easily achieved and all the desired constituents will be consumed, making prior decarbing unnecessary.  Vaping and dabbing with quality equipment allows for precise temperature control to target cannabinoid and terpene components, attain very high conversion and dial in desired effects, using temps to control the intensity of the high delivered. With higher quality controllable vaping equipment decarbing is also usually considered unnecessary because you can preserve all the terpenes in your concentrate with high cannabinoid conversion efficiency.  On the other hand, there are people who like to do low-temp dabs to enjoy rich flavors and avoid the possible adverse health issues associated with high-temp dabbing. In this case, it’s possible to lose a good percentage of cannabinoids to low conversion.  The low conversion problem can be solved by decarbing the material, and adding back any terps that were lost in the process, creating a high cannabinoid conversion and high terpene dab.  Likewise, there are many people using vape cartridges with low power batteries that operate at low temps that don’t provide reliable THC conversion, hence much weaker effects than desired.  To insure a more potent delivery of THC some people choose to use decarbed oil and added terpenes to make vape cartridges.

To recap, when deciding if you need decarb or not there are just a few considerations.  First, determine if you desire THC-A, THC, or a combination.  Second, consider your form of consumption and if higher conversion is necessary.  Third, for your use, are the costs of decarbing worth the benefit?  Lastly, can the risk of potential terpene loss be mitigated by adding terpenes back later?




For this exercise I prepared some outdoor GSC flower broken up by hand and separated into 7g bags for a control sample and for each test.  I chose a 7g sample size because it’s representative of what many people may decarb at home for personal use and the results will be consistent with the larger volumes when executed properly.  When processing larger amounts you must make sure the cannabis is not in a thick or compressed layer that would hinder heat transfer and cause unequal and incomplete decarb.


Ovens are notoriously unreliable for temperature accuracy, and to my disbelief, during this exercise I found my Across International vacuum oven was actually off nearly 30°F whereas the oven in my kitchen was spot on.  Here are some things you can do to make using the oven more reliable for decarbing:

  • Before using an oven for decarbing, determine if the internal temperature of the oven matches the temperature you intend to base your decarbing.
  • To measure the accuracy of your oven temp you can put a measuring cup of water in the oven with a thermometer or use an inferred temperature gun to see what the oven temp measures.
  • Remember the areas of the oven that deliver heat will read much higher than the rest of the oven, if possible measure the temperature of the rack, grate, or pre-heated cookie sheet.
  • When checking the internal temperature of the oven or preparing for decarbing, before measuring the temp or beginning a decarb, allow the oven to settle for about 20 minutes after it indicates it’s up to temp.
  • If the observed temp in the oven differs from the actual setting you can either note the difference and adjust the setting accordingly to achieve the desired temperature. For example if your target temp is 240°F but the oven only measures 220°F, try setting 260°F and see if it settles at 240°F and if it does use that correction going forward.  The other option is to use the measured oven temp as is and adjust the decarb time accordingly.
  • If a cookie sheet is being used, make sure it’s preheated with the oven and up to temp before putting anything on it to process.


I chose to compare methods that range from the traditional use of an oven, a couple of gadgets, and a couple of methods I worked up myself.  First we’ll look at using the oven with foil tents, sealed canning jars and, vacuum packs, then the sous vide, steaming, and the Ardent Nova.  In comparing each method and the respective results I was looking for high THC conversion, low CBN conversion, possible terpene preservation advantages, ease of use, odor, and general advantages or disadvantages of each.

Oven – Foil Tent

  • 240°F for 60 minutes – 100% THC conversion, no CBN conversion
  • 260°F for 40 minutes – 99.6% THC conversion, no CBN conversion

This is a simple method, just put the cannabis on some foil and fold it loosely like a tent then fold over the ends to completely seal.  The folded shape doesn’t help control the odor much, but it does prevent the cannabis getting overly toasted as it would without the foil protection.  This was the easiest of all methods and both samples were effectively fully decarbed.  The only real downside to this method is there is a decent amount of odor, there will be no secrets about what you are doing.

Oven – Vacuum sealed pack

  • 240°F for 60 minutes – 100% THC conversion, no CBN conversion
  • 260°F for 40 minutes – 100% THC conversion, no CBN conversion

After doing the foil tent, I thought a vacuum sealed pack would perform the same function but better. I had never seen nor heard of this being done so I wasn’t sure if the plastic would melt and ruin the cannabis or not, but I only had one way to find out!  I used a Food Saver unit to vacuum seal the cannabis and planned to place it on a cookie sheet for decarbing.  I preheated the cookie sheet in the oven so it was up to temp along with the oven when the vacuum packed cannabis went in.  After the time was complete removing the samples showed that the CO2 release from the process made the bag puff up a little and there was moisture in the pack that wasn’t there to start.  The pack worked as planned and trapped anything that had evaporated then it re-condensed on the cannabis or the surface of the pack as it cooled.  It wasn’t odor proof but it was a lot less than the foil tent.

A great advantage of this method is being able to capture the vapor and everything remained in the pack. When making butter, an infusion or extraction I would be sure to gather whatever was collected on the surface of the bag by using the pack to do part of the infusion or ethanol wash for extraction. I liked this method, it seemed to work very well, and achieved full decarb.

Oven – Mason Jar

  • 240°F for 60 minutes – 100% THC conversion, no CBN conversion
  • 260°F for 40 minutes – 99.5% THC conversion, no CBN conversion

I’ve been developing a feel for working with sealed mason jars for decarbing for a while.  Like the vacuum pack test, evaporated terpenes are trapped in the jar and re-condense on the glass surface as long as you don’t open the jar until it’s fully cooled.  Then, you can use the jar to do your infusion or extraction and collect all the desirables that would have otherwise been lost.  After the jar cools I put it into the freezer, and use the same jar for doing frozen qwet (Cannabis Oil QWET Extraction Battle of the Wash: Dry Ice vs. Freezer).  The big bonus to this method is there is no smell at all, it’s all contained in the jar.

This process has a couple operational considerations that require attention.  First, a cool jar will require ramping time and uncertain heating, so it’s important to pre-heat the jar.  The jar can be brought up to temp along with preheating the oven.  When it’s time to put the cannabis in the oven, remove the pre-heated jar from the oven, quickly load the cannabis into the jar, secure the lid on the jar, and place it back in the oven.  This process also provides the added advantage of creating a natural vacuum seal later when it cools and before going into the freezer.  Second, the jar shouldn’t be filled too much, it’s best to leave quite a bit of head room to allow even heating of the material.  I usually don’t fill the jar more than 1/3 full at most.  If I do put more in I rotate the jar half way through the process to ensure even heating and add a few minutes to the total time to make up for opening the oven and losing some heat.  Third, I lay the jar on its side to expose as much surface area as possible.  Lastly, glass in a dry heat environment requires caution and you must use your own judgement on if it is safe or not.  I have not had a single failure to this point, but it’s important to understand the possible risks of breaking glass due to temperature changes before trying for yourself.

Sous Vide (gadget) – Vacuum Pack

  • 191°F-194°F for 120 minutes – 93.3% THC conversion, no CBN conversion

I was really looking forward to using the sous vide, regrettably it ended up being a fail, but not by fault of the process.  I believe the process is sound and will work great at lower elevations.  The sous vide I purchased claimed a range up to 199°F which I thought achievable because water here at 5,000 feet boils at 203°F, however, it failed to heat above 191°F on its own.  I added boiling water and it was then able to maintain about 194°F for the remaining time.  The original plan was to perform both 90 minute and 120 minute tests, but with the low temperature limitation I opted to do only the 120 minute.  I’ve heard numerous great reports about this technique and I believe if I were at a lower elevation where water boiled at a higher temperature it would have achieved full decarb.  I think this assumption is supported by the results of the next method, steaming, and the temperatures used there.

The operational considerations are limited with this method.  The only difficulty comes from keeping the pack submerged in the water, especially as it begins to bloat.  I used magnets to hold it down, but any form of weight will do.  One word of caution that gives me a little concern with this method, I didn’t clean this material meticulously so there were some very small but tough stems in the sample.  When the packs vacuum sealed the small stems must have punctured some of the packs because the vacuum seal was lost.  The leaks don’t appear immediately but slowly over time, so if you are going to use this method prepare the vacuum sealed packs in advance and let it set overnight to confirm the vacuum seal is sound or you may end up with water in your pack. Lastly, I have been cautioned by chefs that use these often that the cheaper consumer models are not very reliable or durable, and that can be upsetting when you consider the cost of this gadget.

Steaming – Vacuum Pack

  • 203°F for 90 minutes – 97.3% THC conversion, no CBN conversion
  • 203°F for 120 minutes – 98.1% THC conversion, no CBN conversion

When I started seeing the sous vide being used for decarb I thought, why not just steam a vacuum sealed pack?  The temperature of steam is at least that of boiling water, and maybe just a degree or two higher with the lid in place to create a minor amount of back pressure.  As already mentioned, at 5,000 feet elevation water boils at about 203°F so I hoped this temperature would perform better and overcome the difficulties I had with the low sous vide temps.  I was very happy with this process, there was a very slight odor, and it was no more hassle than the sous vide but required no costly gadget.  Like the sous vide, if I lived at a lower elevation where water boiled around 212°F, I’m sure this would have been a blinding success.

I’m guessing this same process can be used in an Instapot. I have not tried it yet, but there is a consideration that makes this even more interesting.  While decarb isn’t effected by pressure the boiling point of terpenes are, so if you decarb in an Instapot under positive pressure can you preserve more terpenes?  This is a great question I am looking forward to answering at a later date (in the meantime, if someone else can try it, test it, and let us know, that would be outstanding!).

Ardent Nova (gadget)

1 cycle – 100% THC conversion, slight elevation of CBN .09 to 0.15

I’ve been experimenting with the Ardent Nova trying to understand all the claims of this gadget for over a year now.  I’ve run it with many samples, and I’ve even taken it apart to examine the components and structure, and it seems to be pretty much the same tech as a rice cooker.  It has two temperature sensors that run against a timed algorithm and that appears to be the extent of it.  It’s simply a heated cylinder however the claims I’ve seen are extensive: 1) decarb THC with precision, 2) decarb CBD with precision by running two full cycles, 3) decarb plant material as well as oil, 4) use it for infusion.

To me these claims seem overstated and mislead the average consumer to believe it actually does more than I believe it does.  I mentioned earlier that decarbing with precision in the kitchen is quite difficult for a number of reasons, but I see the Ardent solving one of the difficulties by providing a reliable and consistent heat, and if that is what they mean by ‘precision’ then that’s great.  However, decarbing THC, CBD, plant material and oil all precisely, in terms of the different requirements for each of those it’s just not a reasonable claim in my opinion. Looking back at this study Decarboxylation Study of Acidic Cannabinoids: A Novel Approach Using Ultra-High-Performance Supercritical Fluid Chromatography/Photodiode Array-Mass Spectrometry you can see the difference in the curves used at low temp decarbing.  The Ardent uses a low temp for a very long time which as you can see from the graphs flatten with longer times at lower temps.  While it might be a ‘good enough’ I don’t consider it to be precision, and it’s certainly a result that can be replicated for free using other methods. The other precision problem is the inability to differentiate between the amount of mass or density of material loaded into it, meaning it can’t tell if there is a little or a lot loaded, which should be accounted for by the temp ramping algorithm but doesn’t seem to change in the operation when I run a ¼ ounce or more.  On that same point, the inability to distinguish between plant material and oil mass has its own problems for precision, the inability to observe the oil or stir the oil during the process builds in decarb inefficiency and ignores the fact that the oil may have already sustained ample decarb during the extraction process depending on what equipment was used.  So, my impression is that this gadget can be used for all of the claimed applications, but I’m not buying the ‘precision’ argument outside of possibly holding a constant temp and following its own algorithm. Lastly, the suggestion to user the appliance as an infusion appliance as well as for decarb is kind of funny, it’s obviously not designed to be both.

The processing time for 7g was about 2 hours. It was 2 hours where I didn’t have to worry about monitoring it and paying attention to it, that was very easy and worry free.  In fact, after about an 1 hour 45 minutes I just went to bed because I was tired of waiting for it to finish.  This method provided the most toasted sample in this whole exercise and showed signs of being over processed with a not so pleasant aroma.  This was the only method I tested here that had a small volume capacity limitation.

Some people really love this gadget for the ability to simply push the button and walk away without having to monitor or think about if they are getting the best result possible.  With a little bit of thought and minimal effort you can achieve the best possible result without spending this kind of money and having the volume restriction.  I’ve tested this gadget thoroughly and it’s my least favorite of all the methods presented here.


I’m so happy to have had the opportunity do all of these tests side-by-side and present them together, I’ve been wanting to do this for a long time.  It’s clear to me that every one of these methods provides nearly the same outcome with some minor differences, and I think this shows that at home decarb is a lot more forgiving and robust of a process than it’s usually recognized as.  I’m confident that all of these techniques can easily provide full decarb and require very little effort.  Having said that, the methods employing water for the heat source do not appear to be suitable for higher elevations.

To choose the method that best suits your needs think about what tools you already have at your disposal, processing volume needs, how much time you have, if the odor is a factor, if you want to try to recover what terpenes may be present, your value of convenience, and your budget for unnecessary but convenient gadgets.  For me the pre-heated jar method was a clear winner, but everyone will have their own favorite process and I’m confident that whichever one you choose you will achieve great results, so stop worrying about it and just enjoy a stress free decarb.


I feel it necessary to include a short comment on decarbing oil and concentrates.  The chemical action of decarbing and converting THC-A to THC is the same with cannabis plant material and concentrates.  Applying heat for an amount of time to instigate the breaking off of the carboxyl group is the same for both.  In this exercise my focus was on decarbing plant material, but I often decarb concentrates and oil as well.  If you want to give this process a try, simply place the oil or concentrate in an appropriate container and apply heat between 220°F-260°F until the bubbles stop forming.  There are a few important points and cautions to be aware of with this process.  First, when a concentrate is heated up to decarbing temperatures it will be the viscosity of a runny liquid, so it must be contained or it will run off any mat or flat surface and make a terrible mess. Second, as it comes up to temperature tiny CO2 bubbles will appear and they can expand rapidly so make sure you leave lots of room for expansion because it can expand enormously.  Third, it’s very important to stir the oil throughout the process to facilitate an even decarb.  Lastly, once the very small CO2 bubbles stop forming you know the decarb is complete.  My preferred method for this is to use a heated magnetic stir plate with a thermal couple.

Left to right: Decarb in full action, almost done, done

Now I’m out….Stay lifted my friends!



79 thoughts on “Decarboxylation (decarb) 101: Basic understanding and at home method comparison

  1. Fascinating presentation!! I own a Nova decarb machine and I’m quite surprised to read that you don’t think so highly of it. I’ve had mine for over a year, and recently I did wonder about the aroma after decarb: I wondered if the Cannabis was a bit over-toasted. This has me wondering how long its operating life is.

    I will certainly try some of your suggested methods!! Oven decarbing is “IN” again!!!

  2. Great article! I’ve been playing with different methods of decarbing too. I’ve been doing in the oven at 240 for 45 mins, in a sous vide for 2 hrs etc. I have two questions…
    1) If you find the sous vide to be not quite hot enough, any reason why submerging in a pot of boiling water wouldn’t work (using something to keep it from the direct heat of the bottom of the pot)? I guess it would be basically the same as steaming it, huh?

    2) I’ve been decarbing, extracting into ethanol and then boiling off the alcohol to make CO. I’ve always been concerned about the additional time in the heat while boiling off the alcohol overdecarbing the cannabis. On the other hand I figured that the alcohol will never get above 172F (since that’s the boiling point of alcohol), right? SO even if it’s in a water bath of 212F, the oil will not heat above 172 until all the alcohol is gone. So do you think I should be concerned about overdecarbing in the process or no?

      1. Question cuz i am a bit confused. Do you decarb before extraction? Because i saw a video where after the dabs dried they than decarbed. Didnt know if that was a double decarb or you just need to do it once at some point in the process?

      2. Hello. to decarb, Can I put (190proof)Everclear inside the mason jar with the weed and then throw that mix, sealed, inside my steamer for 60-minutes and get the same decarb result or will that harm me? The temperature of the steam reaches 240-250F

      3. Yes—Fissler: Pressure Cooker. I can set it to 10 or 15 (psi) reading 15psi being 240 or 250F to be exact, I can’t recall right now.

    1. Love this stuff!!! Thanks so much for the compilation of information!
      We happen to use an oven thermometer to make sure temps are dialed in for cooking and what not. Easily available in grocery store kitchen isle.

  3. Great article! I appreciate your attention to kitchen science. I have a few thoughts that come to mind.

    Altitude Issues- None of them are a problem here at 223 ft above sea level, but I feel for all you mile highers. To help that, oil gets way hotter than water without the boiling, regardless of altitude. Entry level turkey fryers can hit 350°F or more. The range top with a pot, slow cooker, and possibly rice cooker might be an option as well. So, your Sous Vide or Foodsaver bag techniques could be dialed for higher temps- if you can dial in the temp, perhaps with a thermostat PID. There are 2 potential issues I can think of. 1) Can the bags handle hot oil without dissolving or getting gummy? Note, I use my Foodsaver for freezing all manner of things, but the idea of boiling food in them concerns me a bit regarding chemicals offgassing from the plastic, but that’s my own issue.
    2) The cost of oil can add up. The good side is that basically any cooking oil should work and be reused with no loss. Reheating it will cause it to rancidify and possible scorch, but that shouldn’t affect the product inside. Maybe some dirt cheap vegetable oil from the dollar store, or even spent peanut oil from turkey fryers could be found on craigslist.

    Canning Jars- Man, that idea freaks me out, and I’m going to try it anyway! Brilliant idea about reclaiming terps with an ethanol wash later, I love that concept. How well did that work, flavor wise? A word on canning jar safety.. I apologize in advance. When canning foods, the ring is left completely off, or only loosely threaded on to keep the lid centered. The internal pressure pushes gasses out of the lid, and the vacuum happens as it cools. Otherwise, it’s a potential pressure bomb. Also, make sure the jar is in perfect shape, ideally brand new. Any chips, cracks, or the stress of multiple heatings will degrade the integrity of the glass, including tinking the glass with a hard object (which I’ve done unfortunately). If the lid is on loosely without the ring, it would obviously need to be upright. However, it could be brought up to temp and then have the lid screwed on, if the lid was already hot so as to not crack the glass. Being upright would unfortunately decrease surface area for your herb. A quick Goog search says there are square canning jars out there. This would increase your footprint inside the jar. Secondly, what if you made multiple shelves inside the jar with foil or mesh screens so all the layers get even heat transference? I guess you could always load up multiple jars in the oven too.

    Oven Temps- Consistency is certainly a problem, worse for electric than gas. If you have a pizza steel or stone, you can throw that in during preheat because its mass will store and release heat slower and more steadily than the air in the oven. I suppose bricks or something similar could achieve a similar temp consistency.

    I really rambled more than I intended to, so thanks for your patience. Your informative articles just have my hamster wheel a spinning! I’m seriously considering getting a Source Turbo but that’s a stack of coin I need to justify first, so I’ll continue to read the rest of your site. Thanks, and peace.

  4. I have had good results by placing a sealed mason jar in an instapot on hi for 45 mins. Cool to room temp and then proceed with the dry ice QWET process detailed in this excellent blog.

      1. I have one that just needs a new seal if you want it! It’s an older model, but works great. Just pay for shipping and it’s yours!

      2. I actually purchased one, haven’t used it yet though. Thank you very much for the offer.

  5. If one didn’t care about minimizing the amount green material being extracted how long would you recommend washing in the freezer method for maximum extraction. I decarb in a souse vide. TIA.


    1. If you don’t care about the green then you can skip the freezer and do it at room temp, it’ll be much faster and efficient.

  6. Excellent article, well written and presented. I have been simultaneously decarbing and infusing cannabis in my Instant Pot for a while now. I partially and gently break apart very dry buds, weight them, put them into hot jars that have been sterilized in the Instant Pot, add a measured amount of MCT to within one inch of the top of the buds in the jar, seal with a sterile lid just at finger tight, put back into the Instant Pot, Use the canning function (only available on the “Max” model) and select max pressure for one hour with natural pressure release and no “keep warm” function. When the pressure comes down, remove pot lid and lift out jars to cool. They will pop and seal. There is no smell during this entire process.

    The max pressure setting creates 15 psi and raises the temperature inside the pot to 250 degrees F. For one hour, that’s enough to decarb and infuse at the same time. After it cools down, you can see that the buds are tan instead of green, and have shrunk down below the level of the MCT oil.

    It seems to me that this process would retain the terpenes and decarb the THC at the same time. You can leave the jars sealed and they should last for a long time, right up there on the shelf next to your canned tomatoes. When I want to open one, I set the opened jar into a pot of hot water just long enough to warm up the oil. Then I use a potato ricer to squeeze out all of the warm oil. The potato ricer does the best job of anything I’ve tried to squeeze oil out of vegetable matter. In fact, I ate a big spoonful of the left over squeezed buds and felt absolutely nothing, so I think it’s all been infused out. Since I’ve weighed the buds and measured the volume of oil, if I know the percentage of THC in that cultivar, I can calculate the approximate milligrams of THC in each ml.

    This seems to work well, but I have to drink a lot of this oil to get enough cannabinoids to manage my fibromyalgia symptoms. Instead of sitting around vaping all day instead, I have decided to get a Source Turbo and make concentrate, since I can’t afford to buy those. After making concentrate in the Source Turbo, could I melt a lot of concentrate in a teeny tiny amount of oil and then can it in the Instant Pot in those very small jars? I’m thinking this would decarb it and seal it for storage.

    Opinions anyone?

    1. I would either decarb the plant material first or the oil after. Binding agents will restrict the ability to decarb at the natural temp/rate.

    2. Yes to the Source Turbo. You can do whatever you want with the concentrate, depending at what stage you remove it. I use the Turbo almost on a daily basis.

  7. Sorry, I don’t understand. What binding agents are there and what do they do? Where are they located and how do you get rid of them? Do they hurt anyting if they stay there? How do they restrict the ability to decarb? What is the natural temp/rate?

    1. I probably used the wrong term there, a binding agent is an emulsifier like lecithin. What I should have said is once the cannabis/CBD oil is combined with a carrier (to which it binds) it can inhibit and change/lower the decarb process efficiency.

  8. OK, I see what you mean. The MCT oil may indeed behave like that, but I haven’t noticed any diminished effectiveness. I’m looking forward to receiving my Source Turbo. When you have your CO at the end of the process, do you decarb it then? Like, in the oven? Won’t that destroy the terpenes?

    1. I have decarbed in MCT many times and it seems to work, but I have never been able to test and determine exactly what the conversion % looks like. If I decarb oil I use a magnetic stir plate, but you can also use the oven and a silicone cup. Just remember to stir it often. Decarb and temps always cause terpene conversion, evaporation and simple loss.

  9. Thank you for this clear explanation. So now I’m thinking I should decarb the buds in a sealed half gallon mason jar in the oven, let it cool, then put it into the freezer (or outside in my cold Canadian winter -30 C) along with the alcohol. Then, 24 hours later, wash and run it through the Source Turbo. Since the mason jar is sealed until I open it to pour in the alcohol, perhaps some of the terpenes will still be there. It seems to me that whenever you are losing terpenes, you can smell them floating around your house. If there is no smell when you decarb in the oven with a mason jar, or when you open the jar to add the alcohol, shouldn’t the terpenes and terpenoids still be there?

  10. One more question, please? Can you stop the operation of the Source Turbo and add more wash several times during processing to end up with more product at the end?

    1. It doesn’t save you any time or effort really but it does lower the quality of your extract and increase the likelihood of bumping and making a mess.

  11. I was shocked with your nova report, I use the Nova regularly, the main reason it caught my eye was the lack of power consumption, and heat transfer into the room. I live in a condo with no air conditioning and running the oven in the summer can make the condo next to impossible to be in.
    You brought up the point about the machine does not care about the mass or density, but that happens natural with the amount of mass you put in, due to thermodynamics.

    I saw this when I switch to bigger oil runs on my nova, I run about 15 to 20 grams of oil now and it take about 3 hours to go threw its process.

    They made a new claim of only having to decarb CBD once if your THC-A content was above 1%.

    I should probably get some of my stuff test one of these day to see what is going on. But they keep on selling their product and people like you have done some 3rd party testing and proves it works. My biggest concern is how long does it work for? How do I know if the sensor is registering the right temp? These are question I should ask Nova.

    So to me the only down fall to the nova is lack of calibration for temp, because all the other methods you have shown have the ability to calibrate the temp, which to me is the most important part.

    Ill probably be switch to your heat/stir plate idea in the near future.

    Thank for all your input on decarbing .

  12. Great article. Thank you for sharing your knowledge. Can you recommend a magnetic stirring heat plate?

    1. I use a Scilogic , it’s glitchy. You get what you pay for. Get something with good reviews and a thermal couple

      1. Can you decarb flower thats been washed? I want to use my first couple washes to vape than decarb the washed material and make edibles for the rest.

      2. I suppose so, but personally I would just do the 2nd wash, make the oil, and decarb the oil. If you do your second wash straight away while the material is still wet you will also lose less Ethel to the plant material overall.

  13. I have read this article over and over and have come to a conclusion that I have just one more question BEFORE I start making my oil with the source.
    Like you, I am seriously considering the Mason Jar decarb method, mainly because you notated that many of the terpenes and such would evaporate during the process but would be trapped inside the jar leaving them to be collected back later. Does this mean that many of them will stay intact and go into the oil after washing and running through source rather than be lost forever?

    Now that that question is out of the way – if you don’t decarb before your wash, you get an oil that is rich and full of everything the plant has to offer, losing very little in the extraction process, right? If you decarb the oil, post source, wont all of that goodness be lost anyway? Leaving you to have to add back the lost terps?

    I guess I am asking if decarbing in the mason jar, before washing, will really preserve enough of the terps and such that I wouldn’t have to add back anything in order to make carts with it.

    Also, side question – decarbed plant material has a toasty flavor, which is different from green. Would oil made from material that hasn’t been decarbed before the source and then decarbed after potentially have that same “green” flavor? Or will it cook down to a nutty flavor anyway?

    I love your articles and have soaked up as much of the info as possible.
    Thank you!!!

  14. Do you have the decarb times listed out for CBDa to CBD? I would love to see the test results on that like the THC ones from above. According to the study you posted its looking like a 18% loss rate in the conversion.

    1. Not sure where you are drawing 18% on conversion, I’ll have to look back and refresh my memory. THC conversion is accepted to be around 13% in molecular weight.

      1. I’m seeing 18% in the study as well, and with constant debate about whether CBDa or CBD has more health benefits I used figure 6 (and your experience with mason jar decarbing along with two oven thermometers to keep an eye on the actual oven temp…still not sure if the internal temp of the mason jar is the same? I do pre-heat it and fill it quickly once at desire temp) to run my CBD flower for 25 mins at 110 degrees hoping to replicate their 0.6 CBD / 0.2 CBDa ratio. I winterized my decarbed flower, washed for 5 mins with ethanol and ended up with a nice golden finish after filtration. Left for 24hrs in freezer, ran SourceTurbo, mixed with MCT in a jar in a slower cooker and thanks to you, I have something I’m pretty happy with for a first try. Your blog is god-like, and I appreciate your efforts.

        Still curious about if that Decarb study applies to CBD flower (it says extracts?). I want to dial in my CBD decarb methods.

        Also curious about using my bubble bags to “dry sift” all my trim before freezer/washing/sourceturbo. Less frequency and higher potency for each run I’m thinking.

      2. 1) Thank you very much for the kind words. 2) CBD is typically taking 2x of time compared to THC at any given temp. I may have some variation for that coming soon, but for now that is what I am following for myself. 3) I’m not following you on the “Left for 24hrs in freezer” the way you included it here. You mean you put the golden wash you created back in the freezer then just processed it, or you filtered again for winterization? 4) Checkout the Hash, Rosin, EtOH Ecosystem post. It has most of the information you need for your question on kiefing the trim. I think it will save quite a bit of time and ethanol without a ton of yield loss, especially because its trim…….

  15. I stumbled upon this post in research for a class on decarboxylation that I am going to be teaching in the Oklahoma Market, and I would love to speak with you about your results, methods and testing. Would you be open to a phone call collaboration? I wouldn’t mind paying a small consulting fee for some of your time. You can reach me

  16. Can someone email or text me. I am a hemp farmer getting into the extraction business and wanted to start using source turbos. I have a decent handle on how this works but need someone to help me with some expertise questions. Email or text 704-219-5876

    1. You would have to contact the company directly, they information should be on their website.

  17. Best article by a country mile thank. Comprehensive, succinct and accessible.

    So many repetitive and over simplified articles on the web which barely give any real understanding.

    What Im trying to say is thanks.

    1. I had a question. Everywhere says not to put flower in the oven during preheat. I found out that setting my oven to 215f actually is 240f exact on my digital gauge. Everytime I open the oven after preheat, it spikes like 30-40 degrees. I’ve tried everything, preheating on lower settings etc. If I leave it alone without opening the door, I can maintain 240. Since preheat only takes like ten minutes, could I just throw my foil tent in the oven during preheat?

      1. That ten minutes won’t make any real difference. I would also guess the temp spike in the oven is just the overshoot to maintain an average at your target temp. I’d guess that the overshoot is short lived as well? If so, that also wouldn’t make that much difference

  18. Yeah, the overshoot will keep climbing. I got to do all kinds of gymnastics like cutting off the oven, re preheat at lower temps etc to maintain. It’s easier to just put the stuff in during preheat. It has to get up to temp anyway and besides, it’s only ten minutes. I don’t think I’ll burn off anything valuable this way? What to you think? It will avoid fighting to maintain correct temps.

  19. Oven Mason Jar method
    the temps posted
    240°F for 60 minutes – 100% THC conversion, no CBN conversion
    260°F for 40 minutes – 99.5% THC conversion, no CBN conversion

    Are these temps and time the same for CBD & CBG?

  20. what about those silicone rubber boxes that decarb like the magic butter brand or other ones
    do they work well ? apparently they can take the oven heat !

  21. Hi, how about decarbing kief? I put it in a Mason jar and set the oven for 245 and placed it in te oven for 50 minutes. It is dark brown and will not unstuck from the jar

    1. The oil most likely melted. If using for extraction just use the same jar for the wash and it will collect the oil. If doing an infusion put the carrier you are using in the jar, heat and your infusion is done

  22. The temp ramp will be shorter with kief, and because the way it packs I would be good to rotate. But the fact is, kief is kief, when it gets warm it gets sticky, its not protected by plant material to stick to. Also, if you are decarbing in tradition heat applications worrying about color is kind of pointless.

  23. Great article, thank you for the explanation.
    Since you’ve experimented a lot of decarb options, I’m asking you if I can obtain the same % of THC extraction doing simply a TEA weed (using water, butter/whole milk, buds-of course- and simmering for 15/20 min).
    It’s still an accettable decarb method or should I do one of the methods mentioned above BEFORE doing my tea?

    Thanks a lot in advance!

      1. Thanks, I’ll do that.
        Also, in your opinion, could I decarb and infuse/bake my stuff in separate moments or these two processes have to be done consequently? I’m wondering how weed behave once is decarb; it will lose potencial over time or once it’s done it’s done?

      2. I’m saying if I can do the decarb process and right after that, storing my stuff for an uncertain period of time without losing its potencial.
        Sorry for my bad explanation and thanks again for everything.

  24. Great piece! Will definitely refer back to this. Thank you. I’m traveling & thinking I can use a Micom rice cooker in it’s slow cook mode (212 degrees, I bought a $12 thermometer) for 4 hours to get what I need.

  25. I use one exclusively at this point to do all my decarb. Here is my process. let me know if im doing anything wrong.

    My Method of Decarboxylation

    Some of the benefits to using this method are; terpenes are mostly contained, you don’t have to turn or shake jars, you don’t have to be constantly checking temps, most but definitely NOT all smell is contained, (the smell is not nearly as heavy as when using an oven), in fact I find it quite pleasant! Bonus! Set it, Forget it! The Instant Pot also remembers the previous settings used!

    I have tried almost every way to decarb until the day I got my Instant Pot. Now I have a tried and true method that seems to be very consistent and am happy as a clam.

    Instant Pot Decarb Method – I have the Instant Pot Max
    I only use the High setting as it has an average temp of 245
    I put up to 1 oz in each jar make sure you break up buds into small pieces as this gives you more room in the jar

    Materials and equipment used
    Instant Pot – 1/3rd full with distilled water with basket
    4 – 1 pint mason jars, (filled with hand crushed, NOT ground material).
    Hand tighten lids
    cloth or paper towels to wipe moisture off jars

    Put jars into Instant Pot
    put lid on
    plug into outlet and turn on Instant pot
    press pressure cook
    press High for temp
    turn venting on
    set time for 60 minutes
    press start

    go do something else for awhile

    wait for the machine to cool down before opening
    you will have up to 4 ozs of very evenly decarbed material.
    Rinse and repeat as necessary

    P.S. Things to watch out for
    Do NOT over tighten lids
    when opening jars be aware that there will be significant moisture on top of and under the jar lids wipe tops and carefully remove jars from Pot – Do NOT tip over
    Gently remove each top and set aside
    wipe them dry later
    using a cloth or paper towel gently wipe dry any moisture you see around the outside and inside of the jars
    dump all material into a container for storing until extraction or infusion steps.

    That’s All Folks!

  26. I don’t know about your whole point of view with the Nova I’ve had one for over 2 years and I use it at minimum 7 days a week and it’s the best device on the market. Another issue I have is you have all these figures saying you got 100% decarb on all these different stuff …where is your lab results??? 100% decarb is pretty much impossible to achieve yet you claim you nailed it over and over. Let’s see your lab results man… You’re talking junk about everybody saying things are precision well precision would involve you putting up that evidence 🤔🤔

    1. Looks like you are coming in swinging for a fight? This is pretty common with people with limited understanding of the facts of decarbing coupled with a consumer purchase. Consumers get very attached to their purchases and decisions especially where cannabis is concerned. There’s a reason for that and the blind spot it creates in both objectivity and the ability to continue with learning. In learning there are Principles of Learning that are very influential on peoples’ ongoing opinions (I learned this in teaching people to fly aircraft). A few of them including Readiness, Effect, Primacy, and Intensity all get super charged with cannabis for a few reasons too lengthy to get into here. I see it happen over and over with consumers in the cannabis market buying all kinds of unnecessary things then fervently recommending them to everyone like they’ve just discovered something new. When I explain the reality I get people thankful for my work and appreciate the learning, or, people like you directing hostility at me for simply laying out the truth. I’m not “talking junk,” I’m scientifically laying out the facts. I don’t care at all if you or anyone else likes the Ardent and chooses to buy and use it. What I do care about is that people that read my material walk away from this fully understanding the facts.

      The idea of Familiarity is also at play here. Simply by reading your comment it’s clear that you aren’t familiar or have a firm grasp on the science of decarbing. Your simple supposition that achieving 100%, or the numbers I’ve provided is pretty much impossible is obviously wrong. The only way you would have this idea is if most of your knowledge came from the internet and reading the overwhelming amount of inaccurate information that’s out there. All you have to do is accurately follow what I have written in this article and have the lab testing done yourself and you will see that you are mistaken. If you believe me or not really doesn’t matter as it’s a fact of science and not opinion.

      Let me see if I can illustrate with an example. You are most likely very familiar with mowing a lawn, right? Most push lawn mowers cost about $200-$500. If I came and told you that you really had to spend 10x that and use a $5,000 push mower to do it correctly and precisely you would laugh at me, right? You are familiar enough with the topic to quickly understand the absurdity and that no average home owner needs that kind of precision for mowing a lawn, it’s silly. Your neighbor, who has somehow never heard of mowing a lawn, buys one completely convinced that he’s hit the jackpot with this incredible technology and is going to be upset with you when you tell him it does the exact same job your cheap push mower does. Once you actually understand and are familiar with the decarb science (which I’ve provided in the post) and understand that the Ardent is in reality simply a heated tube on a timer, you will understand that at nearly $400 where they started the FX (or at any price over about $100) is very similar to a $5,000 push mower.

      Now, onto my decarbing data you are questioning. Where do you think I got the data that is included in my articles? I’m not guessing at numbers, these all came from lab testing. I have all the lab tests from all the data in my posts. I condense the data in easier comparative form to make it easier to see and understand it. If I just posted the test result sheets it would not only making writing the post very cumbersome referring to a number of separately displayed sheets it would make reading it quite unpleasant. I have no reason to provide anything but accurate data, I have no dog in the fight with the exception of trying to help people and to provide the most accurate information possible to our community.

      Finally, I’ve been kind enough to thoroughly respond to your somewhat aggressive comment as pleasantly as possible and this is all I have to say on the subject and have no intention of reading or responding to any further replies. Have a Merry Christmas and Happy Holiday Season.

  27. Hi there. Great article. Can I ask what you would decarb kief at in one of those silicone boxes? I do about 65 grams at a time. Thank you for your time.

    1. Probably just a little shorter than flower. The main thing is making sure the kief is able to heat thoroughly and evenly. If you are running an extraction on the kief you might run it and then decarb the oil like I do in the “Jar Tech Decarb” post.

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