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How long does freeze dried food last?

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Short answer

It depends mostly on packaging and storage. Harvest Right states that freeze dried food can last up to 25 years when it is fully dry, sealed in mylar with an oxygen absorber and stored cool and dark. That is a maker's claim, not a USDA figure. Food in jars you open often, or in bags that are not airtight, keeps for much less time.

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Long shelf life is the main reason people buy a home freeze dryer, so it is worth knowing where the big numbers come from and what actually limits them. This page explains the maker's claims, the packaging they depend on, the factors that slowly lower quality, and how to check stored food before you eat it. It is written for home freeze dryer owners, and for anyone buying freeze dried food to store. It is quality guidance, not a safety guarantee.

What the shelf life claims mean

Freeze dried food lasts a long time because most of its water is gone, and microbes need water to grow. Harvest Right's 25 year figure assumes the food was dried fully, packed in an oxygen and moisture barrier such as mylar, given an oxygen absorber, sealed well and kept in a cool, dark place. Commercial freeze dried food makers give similar long figures for their sealed cans and pouches.

The USDA does not publish a shelf life for home freeze dried food. When you see a long number, read it as the best case under ideal packaging. Real results depend on how you dry, pack and store. Our storage life by method tool shows each figure with its source.

  • Frozen at 0 FSafe indefinitely; best quality 1 to 12 months by foodUSDA FSIS
  • Vacuum sealedSame freezer times, less freezer burnUSDA FSIS
  • Home cannedBest quality within 1 year, cool and darkNCHFP
  • Home driedFruit about 1 year at 60 F, 6 months at 80 FNCHFP
  • Freeze driedUp to 25 years in mylar with an oxygen absorberMaker claim
Storage guidance by method and who published it. USDA FSIS and NCHFP figures are quality guidance; the freeze dried figure is a maker's claim, not a USDA number.

Shelf life by packaging

Packaging decides how fast moisture and oxygen get back in. This table compares common choices in general terms. It shows how they rank, not specific years.

  • Mylar bag, oxygen absorber, heat sealed

    Moisture and oxygen barrierStrong barrier, blocks light

    Best useLong term storage

  • Glass jar, oxygen absorber, sealed lid

    Moisture and oxygen barrierStrong barrier, lets light in

    Best usePantry stock, store in the dark

  • Vacuum sealer bag

    Moisture and oxygen barrierSome oxygen and moisture passes through over time

    Best useShorter term storage

  • Zip top bag or opened container

    Moisture and oxygen barrierWeak barrier

    Best useFood you will eat soon

How packaging affects freeze dried food

Note.Oxygen absorbers are only for food that is fully dry. Low oxygen packaging with moist food can allow Clostridium botulinum to grow. If freeze dried food is not crisp all the way through, dry it more before packing.

What lowers quality over time

  • Moisture. Freeze dried food soaks up humidity fast. Once it softens, it spoils far sooner.
  • Oxygen. Oxygen makes fats go rancid and fades color and flavor. Oxygen absorbers help.
  • Heat. Warm storage speeds every quality change. A cool, steady spot is best.
  • Light. Light fades color and some vitamins. Mylar blocks light; glass does not.
  • Fat. High fat foods such as fatty meats, nuts and some dairy go rancid sooner, even when sealed well.

How to get the longest shelf life

For a step by step packing routine, see how to store freeze dried food.

  1. 1

    Confirm food is dry all the way through. Break the thickest pieces to check for cool or damp centers.

  2. 2

    Pack it soon after the batch ends, before it picks up humidity.

  3. 3

    Use mylar bags or jars with an oxygen absorber sized to the container. See the oxygen absorber size chart.

  4. 4

    Seal fully. A heat sealer or a vacuum sealer that handles mylar gives a reliable seal.

  5. 5

    Label each bag with the food and the date.

  6. 6

    Store in a cool, dark, dry place and rotate older stock forward.

Once a bag is opened

After you open a bag, the clock speeds up. Humidity gets in each time you open it. Reseal it with a fresh oxygen absorber if you can, or move the food to a smaller airtight jar. Plan to use opened food within weeks rather than months, and sooner in a humid kitchen.

Rehydrated food is no longer shelf stable. Treat it like fresh cooked food: refrigerate it and use it within the time you would use leftovers.

How to check stored freeze dried food

Before you eat stored freeze dried food, check the package and the food. A mylar bag that was sealed with an absorber is often slightly pulled in. A puffed bag or broken seal is a warning sign.

The food should be crisp and dry. If it is chewy, soft, sticky, clumped, discolored or smells off or rancid, throw it out. Do not taste food to test it. Home freeze dried food that was raw before drying, such as raw meat or eggs, must still be cooked to a safe temperature after rehydrating.

Frequently asked questions

Does freeze dried food really last 25 years? That is Harvest Right's stated figure for properly dried food sealed in mylar with an oxygen absorber and stored well. It is a maker's claim, not a USDA number.

How long does freeze dried food last in a jar? A well sealed jar with an oxygen absorber protects against moisture and oxygen, but not light. Store jars in the dark. Jars you open often keep for much less time.

Can freeze dried food go bad? Yes. If moisture gets in, or fats oxidize, it can spoil or go rancid. Soft texture or an off smell means it should be discarded.

Does vacuum sealing work for freeze dried food? It works for shorter storage. Standard vacuum bags let small amounts of oxygen and moisture through over time, so mylar is better for long term storage.

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