How to choose a cooking oil

What smoke point means, and how much it matters

The smoke point is the temperature at which an oil starts to break down visibly and release acrid smoke. Past it, the oil tastes burnt and unpleasant, and it stops doing its job.

It matters, and it is over-emphasised. Most domestic cooking — sautéing, shallow frying, roasting — happens well below the smoke point of almost any oil. It becomes the deciding factor for deep frying, where the oil is held hot for a long time and reused, and for searing, where the pan is genuinely at the limit.

It also varies with refinement rather than with the plant. A refined version of an oil has a much higher smoke point than an unrefined one, so "olive oil" and "extra virgin olive oil" are meaningfully different numbers.

The oils

Rapeseed / canola

Neutral, cheap, high smoke point, widely available. The default cooking oil for most purposes. Cold-pressed rapeseed is a different, grassy, flavourful product for finishing.

Sunflower

Neutral, high smoke point, cheap. Interchangeable with rapeseed for most cooking.

Groundnut / peanut

Neutral, very high smoke point, slightly nutty. The traditional choice for deep frying and stir-frying. An allergen concern.

Olive oil (refined, "pure")

Mild, moderately high smoke point, more expensive than neutral oils. Good general cooking fat.

Extra virgin olive oil

Fruity and peppery, smoke point around 190 to 210°C. Perfectly usable for sautéing and roasting; wasteful, because the aromatics you paid for are destroyed. Keep it for finishing.

Butter

Burns at a low temperature because of its milk solids. Flavour, not heat. Clarified butter or ghee removes the limitation.

Coconut oil

Strongly flavoured unless refined. High in saturated fat and solid at room temperature.

Sesame oil (toasted)

A seasoning, not a cooking oil. Burns readily and its whole value is aroma. Add it at the end.

Nut and seed oils — walnut, hazelnut, pumpkin

Finishing oils. Expensive, delicate, and destroyed by heat.

Which oil for which job

• Deep frying — a cheap, neutral, refined oil with a high smoke point. Rapeseed, sunflower or groundnut. You are using a litre of it, so cost matters.
• Searing and stir-frying — neutral and high smoke point.
• Roasting — anything you like. Olive oil, rapeseed, or a solid fat like dripping or goose fat for potatoes.
• Sautéing — olive oil, or neutral oil with a knob of butter added later.
• Baking — a neutral oil, unless the recipe wants olive oil as a flavour.
• Dressings and finishing — extra virgin olive oil, or a nut oil. This is where the expensive bottle belongs.
• Anything at the end, off the heat — toasted sesame, chilli oil, good olive oil.

Storing and reusing

• Cool, dark, sealed. Light and heat make oils rancid, and rancid oil tastes of crayons and old nuts.
• Not next to the hob. The most convenient spot is the worst one.
• Buy the size you will use. A large bottle of a good oil that sits for two years is worse value than a small one.
• Reusing frying oil — strain it while warm, store it airtight and dark, and use it a few times. Discard it when it darkens, smells off, foams, or smokes at a lower temperature than it used to.
• Do not pour oil down the sink. Let it cool, put it in a sealed container, and dispose of it with household waste or at a collection point.

Common questions