Understanding the science behind drying/curing

[BreezeEazy]

I'm sure we can all sit down and tell a story or two about some really high quality bud we ran into. I'm in a new medical state so it isn't common to get top notch in my area, such a shame, right? Good bud, sure, but high quality is rare. Those fine sweet citrus smells in some pineapple strains, the cheddars that actually smell like cheese. Blueberry strains that live up to the stories, and smoke that is so smooth you're taking record size bong tokes...

I'm not looking for a tek on how to cure, instead, I'd like to discuss the process and try to understand what actually is happening.

It is the general consensus among growers that the slower the dry, the better, and the longer the cure, typically the better the smoke. In dry places I find that using paper bags is a great way to slow down the drying process. I've found that the longer I can drag out the drying process while avoiding mold, the better the product. Slowing it down also helps with keeping the buds 'even' in moisture content. This actually makes the curing process so simple because once they hit the jar you shouldn't see huge spikes in RH. Simply seal them in a jar and forget about them kind of approach.

Now this is where I get a little lost. I've read oxygen was the catalyst for the curing process but makes me wonder when light, oxygen, and heat can degrade THC.

The other one is getting full aromatic potential out of the plant. I assume this part has a ton of variables. Resin production and terpenes during growing being the primary influence, which are influenced by light spectrum, stress, amount of light, genetics, etc.

That might make temperature the most crucial variable, outside of the very obvious being humidity when drying. Temperature can raise and lower the RH in the air. The other influence temperature will have is on terpenes. I've found no concrete proof yet but I'm under the impression that temperature on the higher side of the range or even exceeding will negatively impact the aromatic potential of your product. Therefore, being on the lower range of temperature would give rise to the full aromatic potential of your product. Of course, too cold can also be a bad thing.

Now for what is happening in a nutshell from what I've gathered.... I've read it in two different ways so I'll share both as well.

Story #1

As the plant is drying, not only is moisture, but chlorophyll and other pigments are evaporating from the bud. If you dry too fast, some of the pigments don't have enough time to leave the bud so they get locked in leaving a harsh taste.

Story #2

As the plant is drying, we are attempting to control this process in the effort to allow the slow conversion of chlorophyll into sugars, which happens only under idea conditions.

Two different stories, but with the same ideology why a slower drying process is better. The same stories apply for when in curing too as there are still trace amounts of chlorophyll, etc., still left and this is why we continue to cure. I'd also like to point out that maybe this is why we have two different camps on the issue whether we should flush a plant or not, and why some people swear you can't tell the difference between organics or synthetics after drying/curing.

The above is just what I've gathered from trying to understand drying and curing which is suppose to be an art. I definitely welcome input on the subject and anything pertaining to achieving full aromatic potential. :rollitup:

 

[180]

You're definitely figgering things out, avo. :thumright: I agree with what you say above, except for Story #1.

Chlorophyll and other pigments (anthocyanins, etc.) CANNOT "evaporate" from the bud (though terpenes can, as you point out, if things get too warm). They do degrade to other compounds (somewhat??) during curing, but as long as the bud is green, there's chlorophyll there.

There are certain compounds that help the bud retain some moisture. Sugars are in this category, so the final "brix" or sugar content of the bud affects curing. How to increase the brix?

As to the "smoothness" or the smoke, yup curing is part of that, but like you I am not sure why. Part of it is the terpenes decreasing; terpenes irritate throat and lungs, making you cough. But obviously the terpenes also give the weed its aroma (and part of its high), so you don't want to decrease them TOO much....

 

[webfish]

Nitrogen is what give plants their harsh green flavor so if you reduce that during flower your off to a good start, then clear at the end, the plant will use up most of the nitrogen in the system curing is balancing between the moisture dryness and flavor, the idea that curing over long periods of time is an old school myth, as soon as two weeks the THC begins to degrade and convert, terpins in the resins are drying out and losing potency. The best way to perfect your cure it to test using a well known lab, this will get your potency at its highest level during the process, the flavor you can test yourself!

 

[Pa-Nature]

Nitrogen is what give plants their harsh green flavor so if you reduce that during flower your off to a good start, then clear at the end, the plant will use up most of the nitrogen in the system curing is balancing between the moisture dryness and flavor, the idea that curing over long periods of time is an old school myth, as soon as two weeks the THC begins to degrade and convert, terpins in the resins are drying out and losing potency. The best way to perfect your cure it to test using a well known lab, this will get your potency at its highest level during the process, the flavor you can test yourself!

So true as the flush is a very necessary thing unless you are sure of your plants color when finished .
In my last harv the plants were very well drained of N/color....made the cure...... shall we say mostly on the vine
As for the cure after 1 month I feel no more change will be had nor do I see a huge drop in potency
But less color change in drying process

 

[Professor Iglofski]

I believe that the general consensus for a slow dry is simply so their is enough moisture in the plant for whatever the metabolic processes to continue breaking down the chlorophyll. Once the moisture level drops below a certain point that process stops. If the relative humidity is above 60% or so, no matter how long the plant continues to hang it will also continue to fade in color, eventually gaining a straw like color. However, in my experience, after 2-3 weeks there is nothing gained by drying it slower or letting it hang longer. Flavor and odor starts to degrade. Some places are too dry for this to occur by just hanging so paper bags are used as a way to delay the dry and keep the chlorophyll breaking down.

After this point comes the jar stage. Its always been my opinion that if the buds are so moist that the jars need to be burped or vented, then its too soon for the jars. I see the jar stage as slowing down the metabolic processes to almost but not quite a stop and maybe favoring some further processes that don't require oxygen. The buds are almost completely dry, the stem snaps, but there is a touch of softness to the flowers. This leaves enough moisture for the subtle anaerobic processes to continue and break down the plant matter very slowly while the resins are not oxidized. I have noticed that a half full jar will not cure the same as a full one. If there is a lot of air space in the jar it will end up stale if it sits for a while. Full jars will smell good and fresh for a long time. If we were taking it to extremes we would cure in jars filled with argon or some other inert gas. Because the resins are not oxidizing/breaking down, but the plant matter is slowly breaking down, the resin flavor and aroma becomes more prominent, the smoke more concentrated with resin vapor and less combustion byproducts, smoother and more flavor. That's what I think is going on with curing.

As Annaba stated, not all strains seem to benefit as much from this treatment. Some strains I like better when they are fresher, however, most strains seem to get subtly better over time if the jars are not opened.

 

[Reed Man]

For what its worth... i like to consider the jarring phase sort of like a crockpot. All those terpines on the exterior plant tissue just cramped up in a full jar, marinating those buds in aroma. Thats why theres a rush of aroma when the jars opened.

All that concentrated scent is somehow assimilated into plant tissue via the h20 phase or air space created when tissue dries, IMHO. To me this makes more sense than any actual improvement of product after 2 weeks of storage. It just soaks up more released smell/flavor with time...

 

[BreezeEazy]

You're definitely figgering things out, avo. :thumright: I agree with what you say above, except for Story #1.

Chlorophyll and other pigments (anthocyanins, etc.) CANNOT "evaporate" from the bud (though terpenes can, as you point out, if things get too warm). They do degrade to other compounds (somewhat??) during curing, but as long as the bud is green, there's chlorophyll there.

There are certain compounds that help the bud retain some moisture. Sugars are in this category, so the final "brix" or sugar content of the bud affects curing. How to increase the brix?

As to the "smoothness" or the smoke, yup curing is part of that, but like you I am not sure why. Part of it is the terpenes decreasing; terpenes irritate throat and lungs, making you cough. But obviously the terpenes also give the weed its aroma (and part of its high), so you don't want to decrease them TOO much....

I agree that pigments can't evaporate from the bud like story one. Story one was actually from dinafem. The second story was from harborside. I prefer the latter for what is going on myself. I'm glad you poked your head in here to comment on terpenes and what not.

Nitrogen is what give plants their harsh green flavor so if you reduce that during flower your off to a good start, then clear at the end, the plant will use up most of the nitrogen in the system curing is balancing between the moisture dryness and flavor, the idea that curing over long periods of time is an old school myth, as soon as two weeks the THC begins to degrade and convert, terpins in the resins are drying out and losing potency. The best way to perfect your cure it to test using a well known lab, this will get your potency at its highest level during the process, the flavor you can test yourself!

I disagree at the moment. Lots of people claim they don't flush and you can't tell. We attempt to flush the plant of chlorophyll and nutrients in effort to make a better product but it sounds like that is what a slow dry and curing process does naturally. Makes me wonder if flushing prior to harvest might negatively impact yields.

So true as the flush is a very necessary thing unless you are sure of your plants color when finished .
In my last harv the plants were very well drained of N/color....made the cure...... shall we say mostly on the vine
As for the cure after 1 month I feel no more change will be had nor do I see a huge drop in potency
But less color change in drying process

Thanks for dropping in, Pa, always nice to hear your thoughts.

I believe that the general consensus for a slow dry is simply so their is enough moisture in the plant for whatever the metabolic processes to continue breaking down the chlorophyll. Once the moisture level drops below a certain point that process stops. If the relative humidity is above 60% or so, no matter how long the plant continues to hang it will also continue to fade in color, eventually gaining a straw like color. However, in my experience, after 2-3 weeks there is nothing gained by drying it slower or letting it hang longer. Flavor and odor starts to degrade. Some places are too dry for this to occur by just hanging so paper bags are used as a way to delay the dry and keep the chlorophyll breaking down.

After this point comes the jar stage. Its always been my opinion that if the buds are so moist that the jars need to be burped or vented, then its too soon for the jars. I see the jar stage as slowing down the metabolic processes to almost but not quite a stop and maybe favoring some further processes that don't require oxygen. The buds are almost completely dry, the stem snaps, but there is a touch of softness to the flowers. This leaves enough moisture for the subtle anaerobic processes to continue and break down the plant matter very slowly while the resins are not oxidized. I have noticed that a half full jar will not cure the same as a full one. If there is a lot of air space in the jar it will end up stale if it sits for a while. Full jars will smell good and fresh for a long time. If we were taking it to extremes we would cure in jars filled with argon or some other inert gas. Because the resins are not oxidizing/breaking down, but the plant matter is slowly breaking down, the resin flavor and aroma becomes more prominent, the smoke more concentrated with resin vapor and less combustion byproducts, smoother and more flavor. That's what I think is going on with curing.

As Annaba stated, not all strains seem to benefit as much from this treatment. Some strains I like better when they are fresher, however, most strains seem to get subtly better over time if the jars are not opened.

Lots of good enough in there! I'm glad I fill my jars up pretty full then for full aromatic potential in the curing process. Sounds like you know a thing or two ;). I'm enjoying the paper bag a lot to slow down the drying a lot as you mentioned. Curious, is turkey bags better or no?

Strong teamwork in here

 

[webfish]

Based on what?

I disagree. SOme strains benefit more than others, no doubt, but smoothness an high complexity are enhanced over time IMO. With some strains it totally changes the hightype...Trainwreck fer example...Island Sweet Skunk, Schrom...

...at least in my experience.

Based on potency only, we have dones quite a bit of testing using the same product several times over the period of a few days weeks and months, the product after six months is nothing like what you started with speaking from a chemical standpoint.

Its hard to give a general rule as far as flushing goes, if you don't use salt fertilizers there is always the argument of what should I be flushing? I have yet to sample anything that hasn't been cleared that can compare to a well balanced nutrient schedule that's cycles down towards the end of the plants life, then given a few days of just water to let the plant use the last of its stored nutrients.

My main point about this is no matter how you cure the plant if its got a green harsh grassy flavor from over feeding it (primarily from nitrogen but potash has a crappy flavor also), you cant cure that out of the plant once its dead.

From a personal standpoint I like flowers that have been given some time to cure, the bag method works well in small quantities, we do the same thing by controlling the humidity in our drying room, adding or reducing humidity as needed, two to three weeks in a cool darkroom works very nicely, the character of the flower is well expressed, and he terpins have matured, diminished somewhat when compared to their heady young freshly picked aroma, but usualy better.
I would always agree each strain to some extent has its own times and humidity levels to reach their utmost expressions of flavor potency and variety.

 

[BreezeEazy]

Based on potency only, we have dones quite a bit of testing using the same product several times over the period of a few days weeks and months, the product after six months is nothing like what you started with speaking from a chemical standpoint.

Its hard to give a general rule as far as flushing goes, if you don't use salt fertilizers there is always the argument of what should I be flushing? I have yet to sample anything that hasn't been cleared that can compare to a well balanced nutrient schedule that's cycles down towards the end of the plants life, then given a few days of just water to let the plant use the last of its stored nutrients.

My main point about this is no matter how you cure the plant if its got a green harsh grassy flavor from over feeding it (primarily from nitrogen but potash has a crappy flavor also), you cant cure that out of the plant once its dead.

From a personal standpoint I like flowers that have been given some time to cure, the bag method works well in small quantities, we do the same thing by controlling the humidity in our drying room, adding or reducing humidity as needed, two to three weeks in a cool darkroom works very nicely, the character of the flower is well expressed, and he terpins have matured, diminished somewhat when compared to their heady young freshly picked aroma, but usualy better.
I would always agree each strain to some extent has its own times and humidity levels to reach their utmost expressions of flavor potency and variety.

Glad to hear you're using the paper bag method since that is what I've started using lately. I want to do the same thing you are doing basically. I was only disagreeing to give light to the fact that maybe that is why there are people in both camps. They can also be flat out wrong lol.

Curious, have you ever double bagged them? I started them off in one bag, 1 layer thick. They still dried out a little to fast. Was figuring I can either add more to one bag to slow it down or I could try double bagging it. Opinions?

Prof Ig is close to what we do around here. We use turkey bags and a few jars.

Something that has not been covered yet. What to do with storing that dry cured bud, especially long term storage, say one year.

I know ya all are going "right, right, we smoke it all up in one month let alone a year"..

after a proper cure and dry, we vacuum seal in freezer bags , sometimes double seal if it is going to be a full year.


if ya wanna get pickey and anal, try some Boveda humidity packs, 62% at 70-72 degrees produces a nice cure.

Those Boveda packets are sweet sounding. Kinda of pricey, but at the same time not too bad, specially if you can reuse them. How are you using your turkey bags?

 

[BreezeEazy]

just like glass jars, for curing, the last stage before they get vacuum sealed.

now i know there are some 5 gal buckets out there that have special lids and are used for curing/storing but the name of them escapes me at the moment, can i blame the romulan oil?....

Got ya.

So about your question on storage... I found this digging around.

http://www.lycaeum.org/~sky/data/grow/c21.html

Scroll to the bottom.

It is actually a pretty good read I though.

 

[webfish]

Here is a good example of how differently two strains react to the same nutrient schedule, the Jedi starts to yellow and drop leaves as soon as we cut back the nutrients (around week 6) the blue dream will stay green through the clear, they both taste amazing, but the Jedi being such a nutrient hog practically clears itself, while the Blue Dream would taste green if it weren't cleared.

I don't use the bags anymore it became too much work as the volume of the co-op went up so we made a sealed room where we can control the humidity (same effect just more manageable on a larger scale), if your product is drying too fast you can slow it down by putting it in a dark cool room with some other product that's not dry yet, or humidify the air the plant will assimilate some of the moisture and increasing RH will also slow down the drying process.

 

[BreezeEazy]

Here is a good example of how differently two strains react to the same nutrient schedule, the Jedi starts to yellow and drop leaves as soon as we cut back the nutrients (around week 6) the blue dream will stay green through the clear, they both taste amazing, but the Jedi being such a nutrient hog practically clears itself, while the Blue Dream would taste green if it weren't cleared.

I don't use the bags anymore it became too much work as the volume of the co-op went up so we made a sealed room where we can control the humidity (same effect just more manageable on a larger scale), if your product is drying too fast you can slow it down by putting it in a dark cool room with some other product that's not dry yet, or humidify the air the plant will assimilate some of the moisture and increasing RH will also slow down the drying process.

Ah, I'm still small time. I harvest 2 plants a month. I haven't broke 4 oz a plant yet but I've been keeping things small until I dial everything in. I need to get some more plants going and those will get the 5 gallon pot and higher watt lighting to try and make a run high yields. Paper bag method has been the best for me so far, but I do want to get to your level with the controlled room to dry in.

I see what you mean about your pictures. That is one thing I'm still unsure of. I ditched the bottles outside of liquid seaweed and what not for growing. I shouldn't have to worry too much about flushing. Guess I'll see how fast my strains feed off it. I just want that bomb flavor and aroma and have become obsessed with the process. I have 2 plants coming down this weekend and my goal is to try and drag them out as close to 2 weeks as possible, then a minimum of 2 week cure. Picked up green and pink(red) post it notes to label my jars for curing now. Strain name, curing start date, 2 week cure date, and 4 week cure date. Green post it for cured and ready to smoke. :rollj:

 

[Xochipilli]

i agree with Webfish on this -- long cures have never done anything for me. I've done carefully controlled cures at 55% humidity. i really didn't like the results of that - at all....

 

[Xochipilli]

i think weed that has been in jars for more than like 3 months starts to loss some of it's Pizzazz.....

 

[Soilgro]

My cures are pretty much full effect after 2 weeks in jars (high wise), but flavor/smell and bag appeal continues up to about 2-3 months, after that my bud seems to start changing to a red color

 

[Soilgro]

[/QUOTE]

damn that Koma look tasty:rollj:

 

[webfish]

I got no argument if THC levels are the only thing bein judged. I totally understand how a lab report of the THC levels are an important tool in yer business. I guess I was on a different page judgin the actual high/hightype from a recreational connoisseur's standpoint.

You get no argument from me there, we are small enough so we consider ourselves to be a boutique club, we do everything we can to produce the same product as guys like you do, we hand manicure, hang dry slowly in a controlled environment etc. but we cant turn each bud daily, open and close jars every few days or hours, do strain specific cures, etc. so in that were never going to be able to compete, but compared to large warehouse grows, well its like mass production compared to hand done, we take a lot of pride in our produce. ;)

 

[BreezeEazy]

Holy chit!!! ...am I supposed to be doin all that stuff???

...hell, I feel lucky if I remember to water once a week er so...

Sorry Avo to get off topic, I don't really understand the curin process on a scientific level...I jus try to dry slow. In my area of the island, it's not a very consistent process, as temps an humidity are changin drastically throughout the seasons, an I don't have any controlled environments like most of the better growers here have...so maybe I shoulda jus stayed outta this thread.

It's all good, man, you have tons of good info. I just cut down another plant last night. I figured I put more in each bag this time, still nothing to crazy as I get my foot wet. I did double bag both bags of bud though. Checked it this morning, and the caliber 3 was reading 70%. My basement is currently 35%. Gotta do everything I can to try and keep these things going slow.

 

[webfish]

Ah, I'm still small time. I harvest 2 plants a month. I haven't broke 4 oz a plant yet but I've been keeping things small until I dial everything in. I need to get some more plants going and those will get the 5 gallon pot and higher watt lighting to try and make a run high yields. Paper bag method has been the best for me so far, but I do want to get to your level with the controlled room to dry in.

I see what you mean about your pictures. That is one thing I'm still unsure of. I ditched the bottles outside of liquid seaweed and what not for growing. I shouldn't have to worry too much about flushing. Guess I'll see how fast my strains feed off it. I just want that bomb flavor and aroma and have become obsessed with the process. I have 2 plants coming down this weekend and my goal is to try and drag them out as close to 2 weeks as possible, then a minimum of 2 week cure. Picked up green and pink(red) post it notes to label my jars for curing now. Strain name, curing start date, 2 week cure date, and 4 week cure date. Green post it for cured and ready to smoke. :rollj:

Sounds like a good plan, a good way to do two plants at a time is to use a hanger, and clothes pins, hang the flowers then cover with a bag, or if its very dry use two bags, pull the hanger top through the bag and hang in your closet, you can write on each pin what it is holding and the date, take notes as you dry and sample, make sure you take a couple hits after its just dry enough to smoke so you have a base line for comparison, could be a fun process, enjoy!

 

[BreezeEazy]

Sounds like a good plan, a good way to do two plants at a time is to use a hanger, and clothes pins, hang the flowers then cover with a bag, or if its very dry use two bags, pull the hanger top through the bag and hang in your closet, you can write on each pin what it is holding and the date, take notes as you dry and sample, make sure you take a couple hits after its just dry enough to smoke so you have a base line for comparison, could be a fun process, enjoy!

Pretty much doing exactly what you said :D

I do like the paper bag because I can write on it a little or easily pin a note to it. I do sample the stuff as it goes into the jar and as the cure goes so I can compare with previous attempt to see how its coming alone. Smoking undone weed sucks soooo much lol.