Freezing and Thawing Without Wrecking the Texture

Ice crystals tear cells

Freeze slowly and ice crystals grow large, rupturing cell walls. On thawing, moisture escapes through those holes: dry food sitting in a puddle.

Freeze fast and you get many small crystals and far less damage. So there is one rule: freeze as fast as you can.

• Spread things thin and flat. A solid block takes hours to freeze at the centre.
• Freeze on a metal tray — metal pulls heat out faster.
• Do not pack the freezer solid; air has to circulate.
• Never put hot food straight in — it thaws and refreezes its neighbours.

Dishes that want that damage

"Large crystals rupture cell walls" above is a description of damage. Several dishes make that rupturing the objective, and there the rules invert wholesale.

• As slowly as possible, and about ninety times. The hwangtae in Hwangtae-guk is pollock hung on the racks at Daegwallyeong for three months, freezing at night and thawing by day roughly ninety times. Large crystals and many holes are the mark of a good one, and the sponge that results holds more liquid than the fish ever did. "Thaw slowly in the fridge" becomes thawing in the sun.
• Where freezing is the only tenderiser. The octopus in Polbo á Feira is better frozen than fresh. Ice crystals rupturing the connective tissue is the only tenderising in the dish — no acid, no long braise, no enzyme — which is the opposite of the rule for almost every other seafood. Galician fishermen beating octopus against the rocks were doing the same job.
• Where it invented an ingredient. Leave Tokoroten outside through Edo-period Kyoto winter nights and repeated freeze-thaw drives the water out, leaving dried agar. That discovery in the seventeenth century created powdered agar as an ingredient, and Yōkan exists because of it.
• Where crystal size is the product specification. Gelato is essentially the business of churning to keep the crystals small, with sugar and milk powder tying up free water so there is less for a crystal to grow from. "Freeze fast" done continuously, by machine.

Air is the second enemy

Exposed surfaces lose moisture, dry out and discolour (freezer burn), and oxidise into off smells.

• Submerge a zip bag in water as you seal it to push the air out — close to a vacuum.
• Wrap tightly in film, then bag it. Double wrapping is reliable.
• Leave headspace for liquids; water expands as it freezes.
• Write the date. Freezing is not indefinite: meat 3–6 months, fish 2–3, cooked dishes 2–3 is realistic.

Thaw in the fridge

• Fridge, overnight: safest, least loss. The surface never sits long in the danger zone.
• Cold water, sealed, 30–60 min: for when you are in a hurry. No water inside the bag.
• On the counter: don't. The outside is at bacteria-growing temperature while the middle is still frozen.
• Microwave defrost: cooks the edges. Only when desperate — low power, short bursts, repeated.

Do not refreeze something you have thawed. The crystal damage compounds, and any bacteria that multiplied in between do not disappear on refreezing.

Things better cooked straight from frozen

• Mandu: steam or pan-fry them frozen. Thawed, the wrappers go wet, stick together and tear. Freeze them spread apart first, then bag them.
• Pierogi: same — straight into boiling water.
• Tteokguk rice cakes: into the broth frozen, though long-frozen cakes benefit from a short soak.
• Stock: frozen in an ice tray you can take exactly what you need, which is useful for Ramen and any soup. See Stocks and broths.
• Herbs: chopped and frozen in an ice tray with olive oil.
• Pelmeni: like mandu and pierogi, except that here freezing is a production step rather than storage. Freezing a tray of them and boiling what you need from frozen is the original method, and thawing them is the failure.

Cooking from frozen spends time, and the medium decides who pays

The list above says which things go in frozen and never says what it costs. Something that starts tens of degrees below the fridge needs longer, and what buys that time is not a property of the food but of what it is cooking in — which is why one freezer hands two dishes on this page opposite instructions.

• Boiling water pays nothing. The medium is pinned at 100°C whatever goes into it, and Pierogi writes down why that is enough: "there is no core temperature the inside has to reach. The only thing that has to happen is that two or three millimetres of dough cook through, so frozen costs a minute or two and changes nothing else." Buuz adds five minutes to the steamer and calls freezing "how the dish is operated" rather than a shortcut.
• Oil pays with its own temperature. A fried surface is on a clock — the crust arrives when it arrives — so the extra minutes have to be taken out of the heat instead. Menchi katsu fries from frozen at 160°C for nine or ten minutes, Chimichanga at 175°C for five or six, and Samosa at its already-low temperature with five minutes added. All three give the same reason, that the lower temperature buys time for the middle. It is the first fry of deep-frying's two temperatures, reached by moving the oil down rather than the food.
• And where the oil cannot go low enough, you thaw. Chicken Kyiv is where that answer runs out: "pelmeni go into boiling water still frozen; these have to spend a night in the fridge first, because frying gives you a fixed number of minutes before the crust burns and a frozen core will not reach 74°C inside it. Same freezer, opposite instructions." What separates it from a pierogi is the raw chicken. Here there is a core temperature to arrive at, and it is a number.

So there are two questions the list never asks: whether anything inside has a temperature to arrive at, and whether the medium's own temperature is yours to move. Cooking meat and resting mentions starting temperature once in passing, as one of the conditions that make "three minutes a side" untrustworthy. Here it is not a variable that spoils a time but one you set.

And the gap itself can be the point. Chicken Kyiv freezes its butter precisely so that the butter lags: "frozen, the crust firms up first and the butter melts behind it — the order is the whole trick." One dish sets the same variable twice in opposite directions. The coating must not start behind; the thing sealed inside it must.

Where in the recipe the freezer goes

Everything above treats the freezer as a place a finished thing waits: it goes in, it takes damage or it does not, and later it comes out. It is also the point at which a recipe gets cut in two, with part of the work done now and the rest on the day. This guide makes that move once, in passing, for one dish — Pelmeni, where "freezing is a production step rather than storage." That is not a peculiarity of pelmeni, and it leaves a question the sentence never asks: where in the recipe the cut should go.

• Put it so that what is left is the part that cannot be done ahead. Coxinha cuts after the breading and before the oil — "Chill 30 minutes after breading … Frozen at this stage they can be fried from frozen." Everything the filling needed has already happened; what is left is the crust, and a crust is the one thing that will not wait, which Menbosha puts plainly: "as it cools the bread reabsorbs oil and softens, and the contrast that makes the dish is gone." Beef Wellington pushes the cut as far down the recipe as it will go — assembled a day ahead, "24 hours in the fridge or two weeks frozen. Bake from frozen without thawing, adding ten minutes."
• But the cut only holds where the stage you interrupted actually stops. Yeast does. Pain au chocolat freezes the pastries before their final prove, and the bullet is one sentence: "frozen before proving they keep a month. Thaw overnight in the fridge, then prove as usual." The stage picks up where it was left. A marinade does not. Galbi says that "portioned and frozen in the marinade, the meat keeps marinating as it thaws — just count the time it already spent marinating before it went in," and the Korean page singles out a pear marinade for that arithmetic, because pear carries the enzyme what marinades do describes as the one that does not stop — "thirty minutes is enough; a few hours turns the surface to mush" — and a slow thaw quietly hands it several more. And a rest has to be finished first: Ćevapi freezes the shaped rolls on a tray "but let them finish the overnight rest first."

So "what freezes well" at the end of this page is not the only question to ask of a dish. The other is which of its stages can be interrupted, and a stage that is still chemically running is where that usually gets decided. The fridge is the instructive contrast, because at 4°C the same move does something else: fermentation basics points out that a yeast dough put there "goes in unfinished and comes out changed rather than paused." Which is why pain au chocolat's own page offers the fridge and the freezer as two different tools on the same pastry — one to deepen the flavour, the other to stop the clock. Once the stage is chosen, wrapping and sealing has the handling: on a tray, not touching, and into the pot without thawing.

When the law requires freezing

Haring is herring eaten neither cooked nor smoked, and Dutch law requires a −45°C blast freeze before it may be sold raw, because of parasites. The crystal damage that causes is not merely a side effect either — it opens the route for the enzymes to get into the flesh, and what ripens haring is the herring's own pancreatic enzymes.

What freezes well and what does not

Well — soups, stews, braises, minced meat, bread, dumplings, sauces, cooked beans.

Badly — anything watery whose crunch is the point: raw lettuce, cucumber, radish; potato (goes grainy); cream sauces (split); hard-boiled eggs (rubbery); yoghurt.

Surprisingly fine — tofu (it turns spongy, which is sometimes exactly what you want), bananas, ginger (grate it frozen).

When freezing helps you cook

• Half-freezing meat for 30 minutes makes it much easier to slice thin — useful for Bulgogi or Jeyuk Bokkeum.
• Rice frozen in single portions works for Kimchi Bokkeumbap, though a night in the fridge is better — see Cooking rice.