Doneness & Temps

Frying Temperatures

Oil Smoke Points Reference

Also: cooking fat smoke points, frying oil temperatures, fat burn points, smoke point chart

The temperatures at which common cooking fats begin to visibly smoke and break down — a critical guide for matching fat to cooking method.

The smoke point of a cooking fat is the temperature at which it begins to produce a continuous, visible blue-grey smoke from the surface — the onset of thermal degradation. At this point, triglycerides break down into free fatty acids and glycerol; glycerol further degrades into acrolein, a pungent, potentially irritating compound. Cooking above the smoke point imparts acrid, burnt flavors and generates harmful volatile compounds. Refined oils (from which impurities, free fatty acids, and fine plant particles are removed) have significantly higher smoke points than their unrefined counterparts. The key fats in approximate descending order: refined avocado oil (270°C / 518°F), clarified butter/ghee (250°C / 482°F), refined coconut oil (232°C / 450°F), refined peanut oil (232°C / 450°F), refined sunflower oil (227°C / 441°F), lard (190°C / 374°F), unrefined extra-virgin olive oil (160–190°C / 320–374°F), unrefined coconut oil (177°C / 350°F), and unrefined sesame oil (170°C / 338°F). Flash point (ignition) is typically 50–100°C above the smoke point.

In photos

Oil Smoke Points Reference at 170–270°C (338–518°F) across common fats. When a fat reaches its smoke point, free fatty acids (FFA) — present in greater concentrations in unrefined oils — reach volatilization temperature. Visual cues: Thin, continuous blue-grey smoke rising from the oil's surface, Sharp, acrid odor distinct from natural fat aroma, Oil surface takes on a slightly darker, brownish tinge.
Oil Smoke Points Reference at 170–270°C (338–518°F) across common fats. When a fat reaches its smoke point, free fatty acids (FFA) — present in greater concentrations in unrefined oils — reach volatilization temperature. Visual cues: Thin, continuous blue-grey smoke rising from the oil's surface, Sharp, acrid odor distinct from natural fat aroma, Oil surface takes on a slightly darker, brownish tinge.
Oil Smoke Points Reference in context — the stages just below and above, side-by-side. The smoke point of a cooking fat is the temperature at which it begins to produce a continuous, visible blue-grey smoke from the surface — the onset of thermal degradation. Target reference 170–270°C (338–518°F) across common fats.
Oil Smoke Points Reference in context — the stages just below and above, side-by-side. The smoke point of a cooking fat is the temperature at which it begins to produce a continuous, visible blue-grey smoke from the surface — the onset of thermal degradation. Target reference 170–270°C (338–518°F) across common fats.
Oil Smoke Points Reference in practice — High-heat stir-fries (refined peanut or rice bran oil). Smoke point is primarily determined by free fatty acid (FFA) concentration, not fat saturation.
Oil Smoke Points Reference in practice — High-heat stir-fries (refined peanut or rice bran oil). Smoke point is primarily determined by free fatty acid (FFA) concentration, not fat saturation.

What happens

When a fat reaches its smoke point, free fatty acids (FFA) — present in greater concentrations in unrefined oils — reach volatilization temperature. Phospholipids and plant pigments darken and off-gas. Glycerol, the backbone of triglycerides, dehydrates into acrolein (a lachrymatory, potentially mutagenic aldehyde). Continued heating oxidizes polyunsaturated fatty acids (abundant in vegetable oils), producing lipid peroxides and aldehydes. Repeated high-heat frying degrades any oil progressively, lowering its effective smoke point with each use as FFA concentration rises.

What to look for

  • Thin, continuous blue-grey smoke rising from the oil's surface
  • Sharp, acrid odor distinct from natural fat aroma
  • Oil surface takes on a slightly darker, brownish tinge
  • Eyes and throat may feel mildly irritated from acrolein vapors
  • Foam or scum forming at the oil's surface with agitation

How to check

  • Instant-read or candy thermometer clipped to the side of the pan — the most reliable method
  • Observe the surface: the first thin wisp of sustained smoke marks the onset — remove from heat immediately or switch to a more heat-stable fat
  • For wok cooking over high heat, infrared thermometers can read the pan surface temperature before adding oil

Food safety

Smoke-point onset is not an acute hazard but sustained high-heat cooking above smoke point generates acrolein and lipid peroxidation products linked in laboratory studies to oxidative stress. Ensure kitchen ventilation when cooking at or near smoke points. Flash point (where oil can ignite) is 50–100°C above the smoke point — never leave oil unattended at high heat.

The science behind it

  • Wok Stir-Fry Oil Temperature

    Requires 230°C+; demands refined high-smoke-point fats like refined peanut or rice bran oil.

  • Hot-Oil Flash Bloom Temperature

    At 180–200°C, most refined oils have safe margin; unrefined sesame oil is too low and is added after blooming.

  • Deep-Fry Temperature

    Standard deep-fry (175–190°C) operates below the smoke point of refined oils, giving margin for extended frying.

  • Clarified Butter / Ghee

    Removing milk solids raises butter's smoke point from ~150°C to ~250°C, making ghee suitable for high-heat sautéing.

Appears in

High-heat stir-fries (refined peanut or rice bran oil)Indian tadka (ghee or refined mustard oil)French sautéed proteins (clarified butter)Mediterranean sautés (extra-virgin olive oil at moderate heat)Deep-fried chicken (refined vegetable or peanut oil)Pastry and confit (lard or duck fat)

References

  1. 1.On Food and Cooking — Harold McGee (Scribner, 2004)
  2. 2.The Food Lab — J. Kenji López-Alt (W. W. Norton, 2015)
  3. 3.Modernist Cuisine: The Art and Science of Cooking, Vol. 2 — Myhrvold, Young & Bilet (The Cooking Lab, 2011)
  4. 4.USDA Agricultural Research Service: Fats and Oils Composition Data

Confidence: high

Notes

Refined vs. unrefined: the key variable

Smoke point is primarily determined by free fatty acid (FFA) concentration, not fat saturation. Refining (bleaching, deodorizing, neutralizing) removes FFAs and fine particulates, dramatically raising the smoke point. Extra-virgin olive oil, despite being predominantly heat-stable monounsaturated oleic acid, smokes at only 160–190°C because it retains chlorophylls, water, and FFAs from cold pressing. Refined 'light' olive oil reaches 240°C.

Comparative smoke point table

Refined avocado oil: 270°C / 518°F. Ghee / clarified butter: 250°C / 482°F. Refined coconut oil: 232°C / 450°F. Refined peanut oil: 232°C / 450°F. Refined sunflower oil: 227°C / 441°F. Refined vegetable / soybean oil: 227°C / 441°F. Lard: 190°C / 374°F. Unrefined coconut oil: 177°C / 350°F. Unrefined sesame oil: 170°C / 338°F. Extra-virgin olive oil: 160–190°C / 320–374°F. Unrefined flaxseed oil: 107°C / 225°F.