The freeze dryer chimes. The trays come out full of strawberries, scrambled eggs, and last night's chili, all of it light as paper. It is 9 p.m., there are two dozen empty jars on the counter, and the only way to seal them is one at a time with a hose. If that is your kitchen, this guide is for you.
The short answer: to store freeze-dried food, package it as soon as it comes off the trays, in a container that keeps out moisture and air, then keep it somewhere cool, dry, and dark. Glass mason jars and Mylar bags are the two containers most home freeze-dryer owners use. For jars, Penn State Extension says to put an oxygen absorber in the jar or remove the air with a vacuum sealer. For Mylar, it says to use an oxygen absorber and a heat seal. The rest of this guide covers when each container wins, what oxygen absorbers do, and how to seal a whole run of jars in a few cycles instead of a whole evening.
We sell vacuum sealers, so read this knowing that. We are not food scientists either. Where this guide makes a storage or safety claim, it links to the extension service or federal source that made it.
What ruins freeze-dried food in storage?
Four things: moisture, oxygen, light, and heat. Every storage decision you make is about keeping those four away from the food.
- Moisture comes first. University of Minnesota Extension says freeze-dried foods absorb moisture easily, that even the humidity in a kitchen can affect them, and that they should be packaged quickly in appropriate containers. It cites USDA guidance that properly freeze-dried foods must be packaged in moisture-proof, hermetically sealed containers.
- Oxygen is second. University of Minnesota Extension notes that the fats in food can oxidize and turn rancid over time when exposed to oxygen. Taking the oxygen out is the job of an oxygen absorber, a vacuum sealer, or both.
- Light and heat are the slow ones. Utah State University Extension calls moisture and temperature the two critical factors in food storage and says direct sunlight speeds the deterioration of both the food and the packaging. Penn State's advice is a cool, dry place without much light: a basement, a dark cupboard, a pantry, or a closet.
One thing to be clear about. The freeze dryer is what made the food shelf stable, by removing the water. Packaging protects that work. It does not replace it. If a piece of food shows a dark spot in the middle when you cut it open, it goes back on the trays, not into a jar. And freeze-drying does not sterilize food. Minnesota Extension says plainly that it does not kill illness-causing microorganisms, so clean handling before the trays matters as much as the packaging after them.
How to store freeze-dried food, step by step
- Check that it is dry. Minnesota Extension's test: take a piece of food from each tray and cut it in half. A dark spot in the middle means moisture, and all the trays go back in.
- Package it right away. Have clean, completely dry jars or bags ready before the cycle ends. Food that sits out on a humid evening starts taking water back on.
- Choose the container for the job. Jars for what you will open and use. Mylar for what you will put away. The next section sorts that out.
- Take the oxygen out. An oxygen absorber, a vacuum sealer, or both. See the section on absorbers below.
- Pack in amounts you will use. The National Center for Home Food Preservation gives this advice for dried foods: every time a package is opened again, the food meets air and moisture that lower its quality. A pint you finish in a week beats a half gallon you open thirty times.
- Label it. The food, whether it was raw or cooked, and the date.
- Store it cool, dry, and dark, and off the floor.
Mason jars or Mylar bags: which is better for freeze-dried food?
Neither one wins everything. They are good at different jobs, and most people who run a freeze dryer end up using both.
| Mason jars | Mylar bags | |
|---|---|---|
| Best for | Food you open and use: snacks, fruit, meal ingredients, the working pantry | Food you put away: bulk storage, camping and travel, emergency supplies |
| Fragile food | Glass does not squeeze what is inside it. Strawberries stay strawberries. | A bag presses on its contents as the air leaves |
| Light | Glass lets light in. Keep jars in a dark cupboard or pantry. | Blocks light |
| Space and weight | Heavy and bulky | Light and flat, fits in a drawer |
| Reuse | Wash the jar and use it again. Open and reseal as often as you like. | Can be cut open and resealed, a little shorter each time |
| What you can see | Everything. A shelf of glass is an inventory. | Only your label |
| What extension sources say | Put an oxygen absorber in the jar or remove the air with a vacuum sealer | Must be used with an oxygen absorber and heat sealed (vacuum sealing the bag is not covered) |
The table rows on extension guidance come from Penn State Extension's freeze-drying guide, which also notes that Mylar bags take up less space than jars or cans.
A plain rule that works: jars for the food you will reach for, Mylar for the food you will not. If you are building deep storage, here is our look at Mylar chamber vacuum pouches, and here is our guide to vacuum sealing dry goods for storage. If you are still sorting out which drying method suits which food, start with freeze-dried versus dehydrated food.
Do you need oxygen absorbers if you vacuum seal?
For jars, Penn State Extension presents them as two ways to do the same job: put an oxygen absorber in the jar, or remove the air from the jar using a vacuum sealer. For Mylar bags, the same guide says an oxygen absorber must be used, and the bag heat sealed. That guidance covers heat sealing alone. If you vacuum seal the bag in a chamber sealer, the absorber is optional, a matter of preference.
Here is how the two differ in practice.
- An oxygen absorber is a small single-use packet that attracts and holds the oxygen left in a closed container. It cannot be reused, and Penn State says it has to be properly sized for the package. Follow the directions from the absorber's manufacturer for sizing and for keeping unused packets fresh.
- A vacuum sealer pulls the air out right now, and the lid snaps down so you can see and feel that the jar is sealed. You can open the jar, take what you need, and seal it again, as many times as you like.
Some freeze-dryer owners do both: an absorber in the jar, then a vacuum seal on top. Minnesota Extension also mentions food-grade moisture absorber packets as an option alongside oxygen absorbers. What neither packet nor sealer can do is fix food that went into the jar damp. Dryness comes first.
The part nobody warns you about: sealing the jars
A home freeze dryer finishes everything at once. Every tray is done in the same minute, and every tray starts pulling moisture from the room. And the usual jar sealing tools do one jar per cycle. Fit the attachment, run the sealer, move the hose, next jar. For two dozen jars that is two dozen cycles, at the end of a day that already had a freeze-dryer run in it.
To be fair to the hose: it works, and it is inexpensive. If you seal a few jars a month, a jar attachment on a sealer you already own is the right tool, and our step by step guide to vacuum sealing mason jars shows how to use it well. The problem is not the hose. The problem is twenty-four jars.
A chamber vacuum sealer solves that, if the jars fit. It lowers the pressure around everything inside the chamber at the same time, so every jar in it seals in the same cycle. The catch has always been height. Most chamber vacuum sealers are 3 to 5 inches tall inside, and a pint jar is about 5 inches tall. We designed the JARMAX with a chamber 8.5 inches deep, so jars stand upright inside it.
How many jars per cycle?
Six pint jars or four quart jars, standing upright, sealed together. Half pints fit on the wire shelf. Twenty-four pint jars take four cycles instead of twenty-four.
How the jars seal
There is nothing to attach. Fill the jars, set the lids on, and put the rings on loose so air can escape. Stand the jars in the chamber and close the glass lid. Set the vacuum time to 25 seconds and press Vac and Seal. Air leaves the chamber and the jars together, so nothing gets pulled across the opening and powdery food stays down. When the cycle ends, air returns to the chamber but not to the jars, and that pressure pushes every lid down tight. Then snug the rings.
The same machine handles the other half of the job. The JARMAX has a 10.5 inch seal bar and heat control for Mylar up to 7 mil, so the jars for this month and the bags for deep storage come off one counter. The JARMAX landing page shows which jars fit and how the whole thing works, and our guide to the best vacuum sealer for mason jars compares it honestly with the hose and the handheld.
Will the jars break?
Glass can break, and you should hear that from us first. Two verified buyers of our USV32 told us so in their reviews. The USV32 is a pouch machine with a chamber 3.5 inches tall, so a jar only fits inside it lying down.
"I also recommend getting the jar sealer accessory; even though you can sit a jar (on its side) to seal dry goods, I've already exploded two jars."
A verified USV32 buyer, May 2026
"I tried sealing a jar, but it imploded so I need to figure out what is an acceptable vac time for jars before I attempt that again."
Ron C., verified USV32 buyer, January 2026
We are not going to tell you a jar can never break. What we can tell you is what the JARMAX changes: the jars stand upright, in a chamber designed for them, with no hose and no laying a jar on its side. Whatever you seal jars with, the habits are the same.
- Inspect every jar. Run a finger around the rim and look the glass over for chips and cracks. A damaged jar does not get sealed. It gets recycled.
- Use canning jars with their two-piece lids. Glass canning jars are what the extension guidance names.
- Stand jars upright and keep them from knocking against each other.
- Follow the jar setting in the manual instead of guessing at a longer vacuum time.
How long does freeze-dried food last?
We are not going to give you a number, and you should be careful with anyone who does. University of Minnesota Extension notes that home freeze-drying is new enough that there is limited information on shelf life. What you control is the list at the top of this guide: how dry the food was, how fast you packaged it, how well the container keeps out moisture, oxygen, and light, and how cool the shelf is. Do those well and you have done what the research says matters.
What a vacuum seal will not do is make anything safe to keep at room temperature that was not already. Vacuum sealing removes air. It kills nothing. University of Minnesota Extension says vacuum sealing a jar does not result in the same shelf stable food that canning provides. Fully dried food can go on the pantry shelf once sealed. Anything moist or perishable still belongs in the refrigerator or freezer. We cover the difference in canning versus vacuum sealing mason jars.
Do you need a chamber sealer for this?
A JARMAX makes sense if
- You run a freeze dryer and every run ends with a counter full of jars
- You homestead or garden and the harvest comes in all at once
- You store in both jars and Mylar and want one machine for both
- You also make broth, stock, or soup. Here is how to vacuum seal soup and liquids.
Skip it if
- You seal a few jars a month. The jar attachment hood does that job well for very little money.
- You store everything in Mylar and never use jars. A standard chamber vacuum sealer is smaller and costs less.
- You are looking for a canner. This is not one.
- You have less than 25.5 inches of clearance and cannot slide it forward. That is how tall it stands with the lid open.
If the freeze dryer is part of a bigger pantry plan, our guide to bulk food storage covers the staples side of it.
See how the JARMAX seals six jars at once or go to the JARMAX product page
From the community: freeze drying and mason jars
These are community members talking about chamber vacuum sealers in general. None of these people reviewed the JARMAX. The JARMAX is new. This is how people in the community talk about this category.
You can use mason jars to pack dehydrated and freeze dried meals (usually soaps/stews). They will last a really long time and usually only require boiling water to prepare.
Community discussion, r/MealPrepSunday
5 doz eggs FD’d and vacuum sealed Freeze dried 5 doz raw eggs , powdered them in my vitamix and vacuum sealed with an o2 absorber in jars
Community discussion, r/FreezeDried
What freeze dryer owners told us
The JARMAX is new, so these are verified buyers of our other chamber sealers, in their own words. Each one says which machine they own.
Questions people ask
How do you store freeze-dried food?
Package it as soon as it comes off the trays, in a container that keeps out moisture and air, then keep it somewhere cool, dry, and dark. Penn State Extension lists glass canning jars, Mylar bags, and metal cans as options, and says that for jars you either put an oxygen absorber in the jar or remove the air with a vacuum sealer. Label every container with the food and the date.
Can you store freeze-dried food in mason jars?
Yes. Penn State Extension says glass canning jars can be used to store freeze-dried food, and that you should put an oxygen absorber in the jar or remove the air from the jar using a vacuum sealer. Jars do not crush fragile food, they are reusable, and you can see what is inside. They do let light in, so keep them in a dark cupboard or pantry.
Are Mylar bags or mason jars better for freeze-dried food?
Each wins a different job. Jars are better for food you open often, for fragile food you do not want crushed, and for a pantry you can see at a glance. Mylar bags block light, take up less space, and travel well, so they suit bulk storage and food you will not open for a long time. Extension sources say Mylar must be used with an oxygen absorber and heat sealed, guidance written for heat sealing alone. If you vacuum seal the bag in a chamber sealer, the absorber is optional, a matter of preference. Plenty of people use both.
Do you need oxygen absorbers if you vacuum seal?
For jars, Penn State Extension presents them as alternatives: put an oxygen absorber in the jar or remove the air with a vacuum sealer. Some people use both. For Mylar bags, the same source says an oxygen absorber must be used when the bag is heat sealed. If you vacuum seal the bag in a chamber sealer, the absorber is optional, a matter of preference. Oxygen absorbers are single use and need to be sized to the container, so follow the directions from the absorber's manufacturer.
What is the best vacuum sealer for freeze-dried food?
One that does not crush the food and that fits your volume. A pouch squeezes fragile freeze-dried food as the air leaves, so jars are the gentler container. For a few jars at a time, a jar attachment on a sealer you already own works. For a full freeze-dryer run, a chamber vacuum sealer deep enough for jars to stand upright seals the whole batch at once. The Avid Armor JARMAX seals six pint jars or four quart jars per cycle and also seals Mylar up to 7 mil.
How long does freeze-dried food last?
There is no honest single number for food freeze-dried at home. University of Minnesota Extension notes that home freeze-drying is new enough that there is limited information on shelf life. How long yours keeps its quality depends on how dry it was when it came off the trays, how quickly it was packaged, how well the package keeps out moisture, oxygen, and light, and how cool the storage spot is.
Will mason jars break in a chamber vacuum sealer?
Glass can break, so treat it with care. Two verified buyers of our USV32, a pouch machine with a 3.5 inch tall chamber, reported breaking jars in it, one of them after laying jars on their side. Inspect every jar for chips and cracks before you seal it, and never use a damaged jar. In the JARMAX, jars stand upright in a chamber designed for them, with no hose and no laying a jar on its side.
Can you vacuum seal freeze-dried food in regular vacuum sealer bags?
You can, but read the fine print. University of Minnesota Extension notes that some vacuum sealer bags made for sous vide or general food storage are not moisture barrier bags and may let air and moisture pass through over time. Pouches also press on fragile food as the air leaves. For long storage, extension sources point to Mylar with an oxygen absorber, or to jars.
Sources
- Penn State Extension: Let's Preserve, Freeze-Drying (containers, oxygen absorbers, storage location)
- University of Minnesota Extension: Freeze-drying food (dryness test, moisture-proof packaging, limits of what is known about shelf life)
- University of Minnesota Extension: Vacuum sealing mason jars (vacuum sealing is not canning)
- Utah State University Extension: Food storage conditions (moisture, temperature, light)
- National Center for Home Food Preservation: Packaging and storing dried foods (pack in amounts you will use)
Keep reading
- The JARMAX mason jar vacuum sealer: which jars fit, how it works, and how it compares
- How to vacuum seal mason jars: 3 methods, step by step
- The best vacuum sealer for mason jars: 3 types compared
- How to vacuum seal soup and liquids
- Freeze-dried versus dehydrated food: what is the difference
- Mylar chamber vacuum pouches for food storage
- Vacuum sealing dry goods for storage
Updated September 21, 2026. Reviewed by Eric at the Avid Armor workbench in Lenexa, Kansas.
