Air frying

Why it works

Hot air moving fast strips away the thin layer of cooler, moist air that sits against the surface of food. That layer is what slows heat transfer and keeps a surface damp, so removing it means the surface dries and browns much faster.

A conventional fan oven does the same thing, more gently, in a chamber ten times the volume. An air fryer's small chamber and strong fan mean the air changes many times a second and there is very little thermal mass to heat, so it reaches temperature in two or three minutes rather than fifteen and browns aggressively.

It is not frying. There is no oil bath, no immersion and none of the even, all-round heat transfer that oil provides. What it produces is a very good roasted surface, which for many foods is close enough that the difference does not matter.

What it does well and badly

Excellent

Reheating anything that should be crisp — chips, pizza, pastry, fried chicken, roast potatoes. It is markedly better than a microwave or an oven at this.

Excellent

Frozen convenience food designed for it. Chips, nuggets, spring rolls.

Very good

Small quantities of roast vegetables, chicken wings, halloumi, tofu, salmon fillets, bacon.

Good

Anything you would roast for two people. It is faster and uses less energy than heating a full oven.

Poor

Anything wet or battered — a loose wet batter drips through the basket and burns.

Poor

Large quantities. Capacity is the binding constraint, and a crowded basket steams exactly like a crowded pan.

Impossible

Deep-fried textures that depend on immersion — proper chips with a glassy shell, tempura, doughnuts.

Using it well

• Do not crowd the basket. A single layer with air gaps. This matters more here than in an oven because the whole mechanism is airflow.
• Use some oil. A teaspoon tossed through makes a very large difference to browning and to how food tastes. "No oil needed" is technically true and produces dry results.
• Shake or turn halfway. The airflow is not uniform.
• Lower the temperature by about 20°C from an oven recipe, and check earlier — often around 20% less time.
• Preheat for two or three minutes for anything you want to sear rather than dry out.
• Clean the basket properly. Burnt-on fat smokes and gives everything a stale taste.

Is it worth having?

A fair summary rather than a recommendation either way.

• If you cook for one or two, reheat a lot of crisp things, or want to avoid heating a whole oven, it earns its counter space.
• If you regularly cook for four or more, the capacity will frustrate you.
• If you already have a good fan oven and cook large batches, it duplicates something you have.
• It genuinely uses less energy than a full-size oven for small quantities, because there is far less to heat.
• It does not replace a frying pan, a saucepan or a hob, and marketing that suggests otherwise is overstating it.

Common questions