Home Ice Cream: What the Machine Actually Contributes

Ice cream can be made without a machine, and plenty of people do. Understanding what a machine adds explains both why the results are better and why some people are perfectly happy without one.

The Problem Is Ice Crystals

The difference between good ice cream and grainy ice cream is crystal size. Small crystals feel smooth; large ones feel gritty.

Crystals grow when a mixture freezes slowly and undisturbed. Constant agitation during freezing keeps them small by breaking them up as they form, and simultaneously incorporates air, which gives ice cream its texture and volume.

That is the entire contribution of an ice cream maker: it churns while it freezes. Everything else is detail.

The Three Types of Machine

• Frozen bowl models: cheapest, require the bowl to be frozen for a day beforehand, one batch at a time
• Compressor models: contain their own refrigeration, work on demand and back to back, considerably more expensive
• Ice and salt models: traditional, cheap, messy and effective

For occasional use the frozen bowl type is entirely adequate, provided you remember to freeze the bowl. For anyone making ice cream frequently, the inability to run consecutive batches becomes the limiting factor. Catalogues listing specialty appliances as a category, such as elite gourmet, generally specify which mechanism a model uses, and it is the specification that determines how the machine fits into your life.

Custard Base or Philadelphia Style

A custard base with egg yolks produces a richer, smoother result, because the yolks act as an emulsifier and interfere with crystal formation. It requires cooking and cooling, which takes time.

A Philadelphia-style base is simply cream, milk, sugar and flavouring, uncooked. It is faster and lighter, and it works well for fruit flavours where richness would mask the fruit.

Neither is better; they suit different results.

The Details That Improve Texture

Chill the base thoroughly before churning, ideally overnight. A warm base takes longer to freeze, which means larger crystals.

Sugar and fat both lower the freezing point and improve texture, which is why low-fat and low-sugar ice cream is characteristically hard and icy. Reducing either has consequences that no technique compensates for.

A small quantity of alcohol also lowers the freezing point and keeps home-made ice cream scoopable rather than rock solid straight from the freezer. A tablespoon of vodka in a batch is undetectable in flavour and noticeable in texture.

Storage

Home-made ice cream lacks the stabilisers that keep commercial versions smooth, and it deteriorates faster. It is at its best within a week.

Store in a shallow container with the surface pressed against cling film or greaseproof paper, which limits the air contact that causes freezer burn and crystal growth on the surface.

Without a Machine

The no-churn method using whipped cream and condensed milk works genuinely well and requires nothing. Alternatively, freezing a base and beating it thoroughly every half hour for the first few hours approximates churning, at the cost of considerable attention.

Both are worth trying before buying a machine, if only to establish whether you will make ice cream often enough to justify one.