How Ice Cream Works
Cooking Skills: Ice Cream 1
Chapter 1 · How Ice Cream Works
Skill goal
Understand what makes ice cream smooth or icy and make four simple ice creams without a machine.
Shopping list for this chapter
The basics
Ice cream is a mix of fat, sugar, water and air frozen so that the water forms tiny ice crystals. Big crystals feel icy and hard; tiny ones feel smooth and creamy. Everything in this chapter, from the cream to the stirring, is about keeping the crystals small.
The five things that matter
| Factor | What it does | If you get it wrong |
|---|---|---|
| Fat (cream) | Coats the ice crystals and makes the texture rich | Low-fat mixes taste thin and freeze icy |
| Sugar | Lowers the freezing point so the ice cream stays soft | Too little: rock hard. Too much: it never sets |
| Air | Makes it lighter and easier to scoop | Too little air: dense and heavy |
| Speed | Fast freezing makes small crystals | A slow freeze makes big, crunchy crystals |
| Stirring | Breaks up crystals while it freezes | No stirring: a solid block |
Equipment
- A freezer-safe tub with a lid. Shallow and wide freezes faster than deep and narrow.
- A whisk and a spatula. An electric hand whisk saves your arm when whipping cream.
- Optional: an ice cream machine. Freeze the bowl for 24 hours first and churn for 20 to 30 minutes. Everything here also works without one.
- A freezer at -18°C or colder. A thermometer in the freezer tells you.
Freezer, allergens and small children
Freezer storage: keep the freezer at -18°C or colder, store ice cream in a covered, labelled container, and eat it within about a month for the best taste and texture (general guidance). Don't refreeze ice cream that has melted completely, and throw it away if it has been left out for hours.Allergens: ice cream usually contains milk (cream, condensed milk), and often egg, nuts, peanuts, soy (in some chocolate and cookies) and wheat (cookies and cones). Check labels, and never serve a nut-containing ice cream to someone with a nut allergy without telling them. Coconut cream or oat cream can replace dairy cream in some recipes, but the texture changes.
Small children: hard lumps, frozen fruit pieces and nuts can be a choking risk for very young children, so keep pieces small and sit with them while they eat.
Try it
Level 1 · Start here
Simple vanilla no-churn ice cream
Three ingredients and no machine. Whipped cream holds the air, condensed milk adds sugar and thickness, and together they freeze soft and scoopable. This one recipe teaches most of what ice cream is.
Ingredients (5 portions)
- 300 ml double cream, well chilled
- 200 g sweetened condensed milk, chilled
- 1 tsp vanilla extract or vanilla paste
- 1 shallow freezer-safe tub with a lid
- Chill the bowl and whisk for 15 minutes if you can. Pour the cold cream into the bowl and whisk until it holds soft peaks (it makes a floppy peak when you lift the whisk).
- In another bowl, stir the condensed milk and vanilla together.
- Fold a large spoonful of the whipped cream into the condensed milk to loosen it, then fold in the rest gently with a spatula, keeping as much air as you can.
- Spoon into the shallow tub, smooth the top, cover and freeze for at least 6 hours (overnight is best). Let it stand for 5 minutes before scooping.
Freezer, allergens and hygiene
Freezer storage: keep the freezer at -18°C or colder, store ice cream in a covered, labelled container, and eat it within about a month for the best taste and texture (general guidance). Don't refreeze ice cream that has melted completely, and throw it away if it has been left out for hours.Allergens: ice cream usually contains milk (cream, condensed milk), and often egg, nuts, peanuts, soy (in some chocolate and cookies) and wheat (cookies and cones). Check labels, and never serve a nut-containing ice cream to someone with a nut allergy without telling them. Coconut cream or oat cream can replace dairy cream in some recipes, but the texture changes.
Whipping cream: use clean bowls and whisks and keep the cream cold until you use it.
Level 1 · By hand
Stir-by-hand vanilla ice cream
No custard, no machine and no condensed milk: just milk, cream and sugar, stirred as it freezes. It is icier than the no-churn version, and that shows you why stirring matters.
Ingredients (4 portions)
- 300 ml whole milk, cold
- 150 ml double cream
- 80 g caster sugar
- 1 tsp vanilla extract or vanilla paste
- 1 shallow freezer-safe tub with a lid and a fork or small whisk
- Stir the sugar into the cold milk and cream for 2 to 3 minutes until it has completely dissolved (rub a drop between your fingers: there should be no grittiness). Add the vanilla.
- Pour into the tub, cover and put in the freezer.
- After 45 minutes, take it out and beat the frozen edges into the middle with a fork or whisk until smooth. Return it to the freezer.
- Repeat the beating every 30 to 45 minutes, 3 or 4 times in all, until it is thick and scoopable, about 3 to 4 hours in total.
Freezer and allergens
Freezer storage: keep the freezer at -18°C or colder, store ice cream in a covered, labelled container, and eat it within about a month for the best taste and texture (general guidance). Don't refreeze ice cream that has melted completely, and throw it away if it has been left out for hours.Allergens: ice cream usually contains milk (cream, condensed milk), and often egg, nuts, peanuts, soy (in some chocolate and cookies) and wheat (cookies and cones). Check labels, and never serve a nut-containing ice cream to someone with a nut allergy without telling them. Coconut cream or oat cream can replace dairy cream in some recipes, but the texture changes.
Level 2 · Fruit only
Banana nice cream
Frozen ripe bananas blend into something very like soft-serve ice cream, with no cream and no added sugar. It is the quickest ice cream there is, and it must be eaten soon after it is made.
Ingredients (2 portions)
- 3 ripe bananas, sliced, frozen for at least 4 hours
- 1 tbsp milk or plant milk, if needed
- 1 tsp vanilla extract (optional)
- Slice the bananas and freeze them in a single layer on a tray for at least 4 hours, then pack into a bag.
- Put the frozen slices in a food processor or a strong blender and blend, scraping down the sides, for 2 to 3 minutes. They crumble first, then suddenly turn smooth and creamy.
- Add the milk only if it will not blend. Eat at once as soft-serve, or freeze for 30 minutes to firm up.
Blender and keeping
Blender safety: don't put your hand or a spoon into the blender while it is running, and let a hot machine rest if the motor smells warm.Keeping: nice cream is best eaten the day it is made. It freezes hard and icy if stored for long.
Small children: hard lumps, frozen fruit pieces and nuts can be a choking risk for very young children, so keep pieces small and sit with them while they eat.
Level 3 · Ripple
A quick raspberry ripple
A ripple is a sauce folded in only a couple of times, so it stays in streaks. A thick, cold sauce is the secret: a thin sauce just turns the ice cream pink.
Ingredients (5 portions)
- 1 batch vanilla no-churn ice cream from the first recipe (or a tub of shop-bought vanilla), softened for 10 minutes
- 150 g raspberries (fresh, or frozen and boiled for a minute, then cooled)
- 2 tbsp caster sugar
- Crush the raspberries with the sugar in a pan and simmer for 5 minutes until thick. Rub through a sieve if you want no seeds, and cool completely, then chill.
- Put half the softened ice cream in a clean tub, drizzle over half the sauce, then add the rest of the ice cream and the sauce.
- Draw a knife or skewer through the mixture twice only, in a figure of eight. Don't stir.
- Cover and freeze for at least 3 hours before serving.
Fruit and freezer
Fruit: wash fresh fruit before use. If you use frozen berries, heat them until boiling and simmer for a minute before using them cold, as is usual UK advice for frozen berries (general guidance: check the pack).Hot sugar syrup and custard: sugar syrup is much hotter than boiling water and sticks to skin, so keep the pan handle turned in and don't touch it. Don't let anything boil over, and keep children away from the hob.
Freezer storage: keep the freezer at -18°C or colder, store ice cream in a covered, labelled container, and eat it within about a month for the best taste and texture (general guidance). Don't refreeze ice cream that has melted completely, and throw it away if it has been left out for hours.
Experiments
Experiment
Freezer set time
2, 4 and 6 hours.
- Make the no-churn ice cream and put three small portions in three tubs. Test one after 2 hours, one after 4 and one after 6.
Look for: At 2 hours it is soft and sloppy, at 4 hours it is soft-serve, and at 6 hours it is scoopable. Write down the time that suits you.
Experiment
Stirring or not
Two tubs, one mix.
- Make the stir-by-hand mix. Freeze half in a tub with no stirring and half with stirring as in the recipe.
Look for: The unstirred half freezes into a hard, icy block that is difficult to scoop. The stirred half is far smoother. This is why ice cream makers churn.
Experiment
Sugar amount
Less, more.
- Make three small batches of the stir-by-hand mix with 30 g, 60 g and 90 g of sugar to 300 ml of liquid. Freeze overnight.
Look for: The least sugar freezes the hardest and tastes bland. The most sugar stays softest and can taste too sweet. Find the amount you like.
Experiment
Container shape
Wide or deep.
- Freeze the same amount of mix in a shallow wide tub and in a deep narrow one. Check them after 3 hours.
Look for: The shallow tub is firmer and set sooner because more of the mix is near the cold. The deep tub is still soft in the middle.
Tasting notes
| What I tried | Method or amount | What I saw | What I thought | Will I do it again? |
|---|---|---|---|---|
| No-churn vanilla | ||||
| Stir-by-hand vanilla | ||||
| Banana nice cream | ||||
| Raspberry ripple | ||||
| Set time | ||||
| Stirring or not | ||||
| Sugar amount | ||||
| Container shape |
Troubleshooting
| Problem | Likely cause | What to do |
|---|---|---|
| Icy, crunchy ice cream | Slow freeze, no stirring or not enough fat | Use a shallow tub; stir during freezing; use full-fat cream |
| Rock hard | Too little sugar | Add more sugar next time; stand it for 10 minutes before scooping |
| Won't set | Too much sugar or alcohol, or the freezer isn't cold | Check the freezer is -18°C; use less sugar |
| Heavy and dense | Cream under-whipped or knocked flat | Whip to soft peaks and fold gently |
| Grainy sugar | Sugar didn't dissolve | Stir the sugar in until dissolved, or warm gently and cool |
| Pink all over (ripple) | Sauce too thin or mixed in | Thicken and chill the sauce; fold only twice |
Freezer and allergens
Freezer storage: keep the freezer at -18°C or colder, store ice cream in a covered, labelled container, and eat it within about a month for the best taste and texture (general guidance). Don't refreeze ice cream that has melted completely, and throw it away if it has been left out for hours.Allergens: ice cream usually contains milk (cream, condensed milk), and often egg, nuts, peanuts, soy (in some chocolate and cookies) and wheat (cookies and cones). Check labels, and never serve a nut-containing ice cream to someone with a nut allergy without telling them. Coconut cream or oat cream can replace dairy cream in some recipes, but the texture changes.
Checkpoint: can you do this now?
- I can explain why ice cream goes icy.
- I can whip cream to soft peaks and fold it gently.
- I can make ice cream with no machine.
- I can swirl in a ripple without mixing it away.
- I store ice cream covered at -18°C.
Next chapter
Cooking Skills: Ice Cream 1, chapter 2 is No-Churn Ice Cream: four flavours from one easy method.