Roasted squash and pumpkin purée, frozen
The safe way to put up smooth pumpkin for pie, soup and muffins — in the freezer, in the amounts your recipes call for.
Makes
A 2 kg butternut or pie pumpkin gives about 1 L of purée, four 250 ml portions
Active time
30 minutes
Total
2 hours including roasting and cooling
Photo Forest & Kim on Flickr · CC BY 2.0
Before you start
What matters for this one
- This is the home route for smooth pumpkin. Purée cannot be canned safely at home at any pressure or time — it is too thick and too variable for heat to penetrate predictably — so it goes in the freezer or it goes in cubes in a pressure canner.
- Cook until fully soft and cool quickly before packing; a big warm tub of purée takes hours to chill in the middle.
- Leave 1.25 cm headspace in rigid containers — purée expands as it freezes and will pop a lid.
- Thaw in the fridge, not on the counter, and use within a few days of thawing.
This follows NCHFP: Freezing winter squash. Quantities, acid and times are theirs; do not scale the vegetables without scaling everything, and do not change the vinegar, lemon juice or processing time.
Ingredients
- Mature winter squash or pie pumpkin with a hard rind — butternut, buttercup, kabocha, hubbard, sugar pumpkin
- Nothing else: no sugar, salt or spice until you bake
Method
- 1
Heat the oven to 200 °C (400 °F). Wash the squash, halve it with a heavy knife (the adult’s job) and scoop out the seeds and strings with a spoon — the child’s job, with the seeds set aside for roasting.
- 2
Lay the halves cut-side down on a lined baking sheet and roast until a knife slides into the thickest part with no resistance, 45–75 minutes depending on size. You can boil, steam or pressure-cook chunks instead; roasting just tastes better and drives off water.
- 3
Scoop the flesh from the rind and mash with a potato masher, or purée in a food processor for pie-smooth texture. If it looks watery, drain it in a sieve for half an hour.
- 4
Set the pot or bowl of purée in a sink of cold water and stir now and then until it is cool to the touch — do not pack it warm.
- 5
Measure into freezer boxes or bags in the amounts your recipes use (a 540 ml tin of pumpkin is about 2 cups), leaving 1.25 cm (½ inch) headspace in boxes. Press bags flat and squeeze out the air.
- 6
Label with squash type, amount and date, and freeze flat until solid before stacking.
Keeps: 8–12 months at −18 °C (0 °F). Thawed purée weeps liquid; pour it off or stir it back in depending on the recipe. Use within 3–4 days of thawing.
Variations: Freeze some of it already seasoned as pie filling base (purée, brown sugar, spice) if you know it is only ever going into pie. Freeze 2-tablespoon blobs in an ice-cube tray for stirring into a toddler’s porridge.
Tested source: NCHFP: Freezing winter squash. Checked October 2026. If a jar did not seal, refrigerate it and use it within a few days. Never taste anything from a jar that is bulging, leaking, spurting or smells wrong — when in doubt, throw it out without tasting.
The crop
Winter squash: when to pick, how to store, what else to make →
A cured squash on a cool shelf is already preserved, which is the whole point of the crop; the pantry work comes in January when they start to turn. Then the best method is to roast or steam the flesh, mash it, cool it, and freeze the purée in 500 ml tubs with 1 cm of headspace — it keeps a year and is pie, soup and baby food on demand. What does not work, and this is the one squash rule to carry in your head, is canning purée: mashed or puréed squash or pumpkin cannot be safely canned at home by any method, because the mass is too dense for heat to reach the centre of the jar in a predictable time, and neither can squash butter. The only way squash goes in a jar is as 2.5 cm (1 in) cubes, boiled two minutes and pressure-canned — 55 minutes for 500 ml jars, 90 minutes for litre jars, at 10 psi (weighted gauge) near sea level — and mashed after opening. There is no water-bath method for any squash. Dried squash chips and leather are a good use of a dehydrator, and the seeds roast.
More for winter squash
- Pressure canning
Pumpkin and winter squash cubes, pressure canned
The only safe way to put squash in a jar: firm cubes in water, which you drain and mash the day you bake the pie.
About 9 × 500 ml (pint) jars from 4.5 kg (10 lb) of squash, or 7 × 1 L (quart) jars from 7.3 kg (16 lb) · 1¼ hours active
The recipe →