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Guide 01 · How it works

What is freeze-dried fruit?

Freeze-dried fruit is fruit that has been frozen and then dried under reduced pressure, so its ice turns straight into vapour instead of melting. This is called sublimation. Because the water leaves without first becoming liquid, the fruit keeps much of its shape, and what remains is dry, light, porous and usually crisp.

Also called
Lyophilization
How the water leaves
As vapour, straight from ice
Typical result
Dry, light, porous, usually crisp
What the process adds
Nothing: it only removes water

Sources Bhatta et al., 2020Uwineza & Zhang, 2026

Published

Freeze

Freezing comes first, and it shapes what follows

Before any water is removed, the fruit is frozen solid. Most of its water becomes ice; a small share stays bound to the fruit’s solids and is dealt with at the very end.

That ice turns the fruit into a rigid, stable structure for drying. The size of each ice crystal also largely sets the size of the pore it will leave behind.

Slower freezing
Larger ice crystals, larger pores and faster drying later. Crystals that grow too large can damage the fruit’s cells.
Faster freezing
Smaller ice crystals and finer pores.

So freezing is a quality decision, not a warm-up. Freezing conditions have been shown to affect the colour, volume and aroma of freeze-dried fruit, and how long it takes to dry.

Sources Yao et al., 2023Uwineza & Zhang, 2026Bhatta et al., 2020

Sublimate

Sublimation: ice becomes vapour without melting

Ice normally melts into water before it evaporates. Lower the pressure far enough and that middle step disappears.

Below the triple point of water, the one combination of temperature and pressure at which ice, liquid water and vapour can coexist, ice cannot become liquid. Given a little heat, it turns directly into vapour. That change is sublimation, and it is the heart of freeze-drying.

The process, in four stages

  1. FreezeWater to iceThe fruit is frozen solid.
  2. Lower the pressureBelow the triple pointThe frozen fruit sits in a sealed chamber while a vacuum is drawn.
  3. Primary dryingIce to vapourGentle, controlled heat drives sublimation. The vapour collects on a very cold surface, which keeps the vacuum working.
  4. Secondary dryingBound water to vapourWater still bound to the fruit’s solids is removed by desorption, at a somewhat higher but still controlled temperature.

Throughout, the fruit has to stay below its collapse temperature. Above it, the drying structure softens and loses its pores. Staying under that limit is a large part of why freeze-drying is slow, energy-intensive and comparatively expensive.

Sources Bhatta et al., 2020Uwineza & Zhang, 2026

Crunch

Why freeze-dried fruit is crisp

Where the ice was, a space remains.

Frozen: ice in each cell
Dried: a pore where the ice was

A simplified drawing, not to scale and not a micrograph.

Sublimation happens while the fruit is still frozen and rigid, so its solids stay largely where they were. What is left is an open, porous network holding very little water. Reviews describe that dry network as brittle, which is what you feel as crispness.

Conventional drying tends to go differently: shrinkage and collapse are common when fruit is dried with warm air, which is why it often comes out denser and chewier. Freeze-dried vs dehydrated fruit sets the two side by side.

Crisp is typical, not guaranteed. Texture depends on the fruit, how it is prepared and the drying conditions: published work includes freeze-dried strawberries that came out neither crunchy nor crispy until they were pretreated.

Sources Uwineza & Zhang, 2026Bhatta et al., 2020

Changes

What freeze-drying changes, and what it does not

Water
Most of it is removed: frozen water by sublimation, then much of the remaining bound water by desorption.
Shape
Often largely kept. Freeze-dried fruit typically shrinks less than fruit dried with hot air, although results depend on the fruit and the process.
Flavour and colour
With most of the water gone, the fruit’s flavour is carried in far less weight, so it tends to taste more concentrated. Reviews report that freeze-drying generally keeps colour and flavour well.
What it adds
Nothing. Freeze-drying only removes water. Whether a product contains anything besides fruit is on its ingredient list.

Sources Uwineza & Zhang, 2026Bhatta et al., 2020

Keep

Keeping the crunch

The same open structure that makes freeze-dried fruit crisp takes up water easily. Left open to the air, it absorbs moisture and gradually loses its crunch, which is why it is packed dry and sealed.

Before opening
Keep the pouch in a cool, dry place, away from direct sunlight.
Once open
Enjoy it promptly: moisture in the air can soften the crunch.
Always
Follow the storage directions on the pouch.

Sources Uwineza & Zhang, 2026

ASTROVE

Freeze-dried fruit, from ASTROVE

ASTROVE is freeze-dried tropical fruit, one kind in each pouch.

Preparation varies by fruit. Mango, Java Plum, Pink Guava and Papaya are puréed and formed into pieces before freeze-drying. Pineapple is peeled and cut into pieces.

Eat it straight from the pouch, scatter a few pieces over yogurt or oatmeal, or add a little crunch to ice cream.

ASTROVE is not on sale in Canada yet. Availability will be announced when it is confirmed.

References

  1. Bhatta S, Stevanovic Janezic T, Ratti C (2020). Freeze-Drying of Plant-Based Foods. Foods, 9(1), 87. doi:10.3390/foods9010087
  2. Uwineza A, Zhang X (2026). Application of Freeze-Drying Technology in the Food Industry: A Review. Foods, 15(4), 790. doi:10.3390/foods15040790
  3. Yao J, Chen W, Fan K (2023). Novel Efficient Physical Technologies for Enhancing Freeze Drying of Fruits and Vegetables: A Review. Foods, 12(23), 4321. doi:10.3390/foods12234321

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