Vacuum sealing mason jars to extend life

[RustyOldNail]

That makes sense, I could not afford anything but the cheapies for my mason jars as I have had over 30-quart jars in the cupboard before...horses for courses.

Well you grow, correct? Your needs are quite different.
I’m just a consumer. Maybe someday I can grow my own, then I’ll have little doubt as to what I may be inhaling, and save $$$.

 

[zeusjames]

I like vacuum sealing because I know the jar is sealed. Like opening a jar of something from the grocery store, it's a good feeling to hear that little woosh when opening the jar.

Moisture level will remain the same after a few days of stabilizing. Damaging oxygen will decline and not be replaced as long as it remains sealed. If worried about too much vacuum then don't apply a lot of vacuum. I apply a threaded ring top to assist the vacuum seal.

 

[General Disaster]

If anyone is interested, I would strongly advise forgetting vacuum storage. As has been mentioned already, maintaining a vacuum is not simple, what you really are talking about is maintaining a minimum pressure. You need accurate pressure readings to have a clue about how effective the container is, what sort of pressure it can maintain.
Next, the vacuum according to physics will reduce the boiling point of all compounds within. Not only will water be boiled off, but terpenes and cannabinoids as well, depending on how low the pressure is, what the temperature is, and the RTP boiling point of each compound (so in effect you're changing the cannabinoid/terpene profile of the plant). Vapour pressure will tend to grow within the jar as these compounds are encouraged to evaporate by the vacuum and gradually replace the air inside.

In addition, I'd judge it highly likely that under a partial vacuum a humidifier may well not work as intended.
I would expect the best way to store is under a non-reactive gas such as nitrogen, probably with some sort of effective humidity control, and out of the light, and preferably at a suitably low temperature. That way, you will experience little leakage into or out of the container as the pressure will be close to equal on both sides. The nitrogen will prevent most of the oxidation that would otherwise break down some of the active compounds.
Most likely the lower the temp, the slower the breakdown of THC to CBN etc. so it will last for longer close to original profile.

The only reason I can think of to apply a vacuum, would be to exclude oxygen, because that, along with light and warmth will be the biggest factors in your weed degrading. But vacuum ovens don't have a vacuum so as NOT to dry things out!!!!
Lower pressure = higher boiling point = more evaporation of compounds!!
If nitrogen is unavailable, it may be CO2 could be used, as it's pretty stable (more than O2, won't cause oxidation) and easy to buy and transport as dry ice (pop a lump in the jar and let it dispel the air as it sublimes into a gas, being heavier than air it collects at the bottom and rises up the jar. Another option could be finding a small cylinder of helium as used for kids party balloons, very stable gas.
What I can't say is whether it would have an impact on a humidifier like a Boveda or similar tech. Maybe the best thing is to humidify in a sealed jar for a few days, then remove humidifier, add unreactive gas and seal. The weed should neither get drier or damper if the jar is left unopened from that point, there's no moisture getting in, and nowhere for moisture inside to escape. Hence, in equilibrium.

P.S. Caveat with the idea of using dry ice, it will tend to make the weed a little damper due to it condensing the moisture out of the air while it's cold - that's why it looks cloudy as it sublimes. Probably not a big issue unless left for more than a minute or so, but I couldn't say for sure.

 

[mcscruffy]

I put it in an earlier message but only the moisture at the outermost layer will be affected. It will boil away until there is an equilibrium which isn't much but will cause the outside to feel dry.

I was also under the impression equilibrium takes seconds vs days but I'm not exactly an expert and learning as I read.

The biggest pro of the vacuum seal is removing the oxygen, but the other factor is there is no airflow in a vacuum. This is what preserves the state because it slows any reaction and degradation from moving gases.

That's what I understand from my research so far, at least....

 

[General Disaster]

It will continue to evaporate until the pressure inside the jar reaches an equilibrium with the solid oils on the plant matter (the cellulose base).
Outer layers mean little, because as it evaporates off at the lower pressures, it jusr reveals a new outer layer! It doesn't really mean anything, although I can see how it may appear to. In the end, it's either there, or it's all evaporated into the empty space in the jar. As it evaporates, it raises the pressure in the jar as the terpene and cannabinoid molecules free up (evaporation) and 'float' off the plant and into the space surrounding it.
This is called vapour pressure - it's the pressure created by the evaporation of liquids due to pressure and temperature (look up Boyle's law for gases if you're interested as to why pressure effects B.P.).

Equilibrium is reached when enough of the oils evaporate to increase the pressure in the jar until it's raised to the point where the temperature is not high enough to evaporate any more of the oils. How long it takes depends on the actual pressure (negative pressure if you prefer to say it that way), the temperature, and the composition of the volatile liquid oils in the jar. If the pressure is not low enough and/or the temperature is not high enough, then an equilibrium can eventually be reached, but also if too high a temp or low a pressure, all the oils may be evaporated without reaching that equilibrium. There are a huge number of variables, even including how big the jar is vs. how much weed is in it!

You are quite right about removing the oxygen, which is a primary factor in THC degradation, but "no airflow" isn't a factor. Simply replace oxygen with a nonreactive gas like nitrogen or helium and that displaces the oxygen so none (or very little) is left in the jar when sealed. But by using a replacement gas, you avoid all those problems that a vacuum, if you can even maintain it, will create for you!

This is a very different process to vacuum sealing a mylar bag to retain the cannabis's volatile components. With the bag, there is no rigidity which is required to maintain a vacuum, it just collapses until the internal pressure is almost the same as the external pressure.

Hope that makes sense, but do say if not and I'll try to explain better.

 

[1800]

In addition, I'd judge it highly likely that under a partial vacuum a humidifier may well not work as intended.
I would expect the best way to store is under a non-reactive gas such as nitrogen, probably with some sort of effective humidity control, and out of the light, and preferably at a suitably low temperature. That way, you will experience little leakage into or out of the container as the pressure will be close to equal on both sides. The nitrogen will prevent most of the oxidation that would otherwise break down some of the active compounds.

This is the way.

A practical example - when dealing with senstive, degradation prone, chemical compounds, you store them under a nitrogen/argon environment. There is really no need to reinvent the wheel here, oxidation is one of the main stability factors in the pharmaceutical industry, so this problem has been solved.

As for access, google "Argon wine preserver".

 

[Photonic]

This is a very different process to vacuum sealing a mylar bag to retain the cannabis's volatile components. With the bag, there is no rigidity which is required to maintain a vacuum, it just collapses until the internal pressure is almost the same as the external pressure.

So would it be best to vacuum seal a mylar bag for oxygen removal/reduction and long term storage if you didn't want to deal with nitrogen/CO2 and jars? Thanks!

 

[General Disaster]

Not necessarily! But it's true that if at suitable moisture levels when packed, and heat sealed properly, and subsequently stored in a cool dark place (the light less an issue obviously), they do work very well over periods of months, but I don't know about a year or more, but it would not surprise me if they came out in pretty decent condition, with maybe a slightly more sedative side with a bit extra CBN, but essentially good to use and no serious degradation. But that is an educated guess, so I'd be cautious if it's large amounts, maybe go glass, but test an eight in a bag in the meantime, to see for the next time around? One thing to watch though, if it gets sealed in with some mold spores, and is damp enough, you may open a bag of ruined weed without having any way to know! In the glass jar, you can unseal and reseal easily, and visually examine without opening. In terms of being probably the most suitable material for storing almost any chemical or mixture short of hydrofluoric acid and the like, glass is damn tough to beat, plus can be unsealed then sealed up again, the bag method means filling a new bag if you need temporary access.

But alternative to vacuum, why not look at seeing if you can get hold of a mini gas bottle of nitrogen or a similar noble gas (though nitrogen's far cheaper), and just flush the bag/bottle with the gas to push out most of the O2 before sealing up. Really it's not vacuum if talking about a plastic bag of some sort, it's about sucking out most of the air, which isn't quite the same thing, as you noted.

But also consider this, if you use a largish container, and fill it as much as possible without damaging the weed, then just seal it airtight and leave it at that (assuming it's humidity is already good). Yes, there is a bit of oxygen in there, and yes, it will oxidise some of the cannabinoids and terpenes in there, but, it's only going to be a tiny fraction and I bet if you never opened it until the end, you'd never be able to tell it hadn't been vacuum or nitrogen stored. It's repeated opening that's the worse thing as it refreshes the oxygen again and again.

If I had to bet I'd say the difference between a Kg stored under nitrogen for a year, and a normal vacuum sealed plastic bag (of suitable material) kept cool and dark, you'd not see much difference after a year. With these things, as a very general rule, it's a matter of diminishing returns. So, minimise the oxygen, keep dark and cool, and you've probably cracked 90% of the task if you've done it well (are the lids really air tight, etc.). You'll have to work much harder to get another small improvement beyond that. Of course quantities matter too. Is it work the effort for an Oz? Probably not as much as for a ton! I have to wonder whether it would be better to just bung the stuff in the freezer in a sealed bag and leave it at that?

 

[RustyOldNail]

In terms of being probably the most suitable material for storing almost any chemical or mixture short of hydrofluoric acid and the like, glass is damn tough to beat, plus can be unsealed then sealed up again, the bag method means filling a new bag if you need temporary access.

Two of my longer storage containers are glass (link below), same company that makes coffee containers. I have several of those in the stainless steel type. I use a 62% Bovida pack, and use a Bluetooth humidity monitor. You press a lot of the air out with the plunger insert.

Cannascape® Glass Cannabis Stash Jar | Planetary Design

Keep your buds fresh and potent with the Cannascape® Glass Stash Jar! Made from sturdy borosilicate glass, it protects from oxygen, light, and humidity.

planetarydesign.com

DESCRIPTION from linked page:

“The CANNASCAPE™ Classic Glass is designed to maximize and maintain the freshness of your flowers (up to 3.5 ounces) in a premium, sleek aesthetic. Our patented stash jar removes excess oxygen to create an ideal environment that protects your flowers from the elements that degrade cannabinoids and terpenes, aka potency, flavors, smell, and the unique qualities of each individual strain. You know, the good stuff that you’ve learned to love and care for.

Science aside, let’s have a conversation about aesthetics because looking pretty matters. The CANNASCAPE™ Glass is made of durable, borosilicate glass & topped with a wooden, airtight lid. Featured on the jar is a writable strain information table to keep track of strain name, harvest date, terpene flavors, percentages, and content breakdowns so you don’t have to worry about holding onto the label it came with.”

As you’ve mentioned, nitrogen is probably the best for long term storage, but I doubt many here would want to deal with the extra process, and expense.

 

[General Disaster]

Oh dear! I can only apologise and abase myself - I have no aesthestics beyond form fitting function, or at least that is my aesthetic!
Ok, maybe not totally, but to me pure design and manufacture is the art I appreciate. Something that does the job in the simplest and most elegant way, made with the best materials for the task, and made to the best quality to suit too. There's the tactile sense of nice materials too, like well finished wood, and really nicely engineered metals, etc.

But at the same time I also suffer a pragmatic approach of where to put my resources, i.e. what I spent real money on and what I use cheap and cheerful stuff for. So for example, no weed of mine is going to live longer than a month or two best, so why fuck about. A simple mason jar or equivalent. The degradation of THC won't noticeably occur in that time. In fact just keeping it sealed with a boveda to stop it drying out, does me fine. I can appreciate all the nuance of the different aspects of physics involved in storage and longevity, indeed I spent quite a long time working in chem labs and the like, wet organic chemistry most of all. But I'm also big believer in the 80/20 rule - 20% effort gets 80% results, after that you're pouring in resources for less and less return. There's a joy in doing it for that alone - to get the best possible result just to see if you can, don't misunderstand me, I don't judge, each to their own, I just have my own way.

That does look like a nice jar, but doesn't do it for me. Just colour me a philistine!

To be honest I mostly just enjoy thinking about ways to do things and how stuff works. I never got properly educated so I learn as I need, and love to think things through for myself as no-one has taught me the answers (and I'm good for little else! ).
It's better than TV, but I don't half waffle on about a load of shit!

 

[RustyOldNail]

So for example, no weed of mine is going to live longer than a month or two best, so why fuck about. A simple mason jar or equivalent.

I use mason jars as well.

The reason I originally began looking into longer term storage solutions, was the lack of flower at the time (illegal).
So when I could buy, I was never sure when I could again. Also thought at the time, having different strains would be fun to access from my own storage.

Well, things have progressed since then, and I can now buy legal flower. The quality can be argued, and in general 30% more expensive, but I do like being able to access the “lab tests”, that is a dispensary mandate. Since I’m not a huge user, it now makes more sense to buy smaller amounts, and just keep it in my CVaults with Bovida pack, and finish it sooner. No more 1-2 year storage. Mason jars are a good budget solution too.

Some may have budget concerns, or other logical reasons for long term storage, but in the other OG thread on this topic, I noted that in the end, vacuum sealing in general was not recommended, though I’ve found many good uses for a hand held vacuum sealer.

FRESH is BEST. So basically I agree with your latest sentiments.

 

[General Disaster]

Vacuum sealing with a bag = air removal (recommended, but displacement with N2 or similar also good)
Vacuum sealing with a rigid body = storage under vacuum (not recommended, no major benefit, too many problems to solve)

There! I kept it down to three lines of text!

Oh no! I feel more coming on, like when you just wiped yer arse and realised there's another one lurking!
...
I think it's simply not worth all the extra effort beyond the basics unless storing huge amounts or something.
Cannabis has a shelf life, and it's far better to plan not to have it hanging around any longer than necessary. But then again, people have all sorts of hobbies, why not that? ¯\_(ツ)_/¯
"Ah yes! '86 was a fine year for Ammo indeed!"

Added to the above, personally, I would be hard pushed to tell the difference in a slight degradation - it'd have to be fundamentally changed! From what I've heard from others who have/do keep bud for long-ish periods, the most noticeable change, if keep sealed, cool and dark, is a slight tendency towards being sedative after maybe a year or so. I for one would be unlikely to notice, having a hard time defining the experience anyway! (at least in a way anyone would make sense of, including myself ironically enough).

 

[mcscruffy]

Good points... though everything boiling off assumes the vacuum space is a large enough volume to allow that much to boil away before full equilibrium, right? This is by no means an area of expertise and why I started the thread, but my initial understanding is the above. I'm storing in packed 4/8/16oz Mason jars, so there isn't much air volume to begin with.

If that is wrong then I would love if you could explain that. I'm not to a point I'd say I'm confident at all!

WRT your comments about inert gas, before I looked into vacuum sealing I actually was considering using my Private Preserve cans (argon gas in a can sold at liquor stores) I have for preserving open wine and whiskeys to purge the jars before sealing. I'm actually now wondering how effective it would be to do a quick spray to purge the air then close and do a light vacuum (let it run for 5-10 seconds instead of 42... recommended minimum 40s by manufacturer). Then it makes me wonder if I've just consumed too much already and this is way overkill... if it would keep the outside of the plant at acceptable moisture or preserve the appearance that would possibly make it worth it to me.

 

[RustyOldNail]

While personally NOT interested in the product below, thought I’d add the link below, as it’s part of this discussion.
It’s an ARGON gas system used with a glass jar.

Buddy Flowers Fresh Kit

The Buddy Flowers Fresh Kit is a one-of-a-kind bundle of cannabis-preserving products working together to create the best weed storage environment.

planetarydesign.com