Cooking Oil Smoke Points: A Chart That Cites Its Sources

An oil’s smoke point is where it starts breaking down and sending up a steady thread of smoke. Refined oils mostly land between 385°F and 490°F, olive covers a wide band by grade, and every published number is one lab reading, not a promise about your bottle.

Most smoke point charts online copy each other and cite nothing. This one shows where each number came from and what refinement state it was tested in, with refined oils in the first chart and unrefined bottles in a second one, because they aren’t the same kind of evidence.

Cooking oil smoke point chart

Two published tables do the work. The Institute of Shortening and Edible Oils tested deodorized samples at 0.05% free fatty acids or less, using AOCS Method Cc 9a-48 (Table VIII, page 21). USDA FSIS publishes a shorter deep-frying list, some rows grouping several oils together, with no refinement level stated.

Look at sunflower. ISEO put high-oleic sunflower at 471°F. FSIS drops sunflower into a 410°F row shared with corn, olive and sesame, naming no cultivar and no refinement level. Sixty-one degrees apart. Corn splits 45 degrees the same way, and olive runs 54 degrees between the FSIS row and the top of the UC Davis band. That’s the honest state of this data.

Unrefined and virgin bottles: what’s actually published, and by whom

Neither big table helps here, and both say why. ISEO tested only samples deodorized to 0.05% free fatty acids or less, and FSIS publishes no virgin or cold-pressed value at all. So no US lab table covers the bottle in your cabinet, and most unrefined numbers online trace to trade references and producer sheets, not to AOCS Cc 9a-48 testing.

Real figures do exist, though. A 2021 study in Frontiers in Nutrition pressed ten oilseeds and measured smoke points with that same AOCS Cc 9a-48 method. Every row below names its publisher and its evidence tier, so you can weigh it yourself.

The gap is bigger than most charts admit. Expeller-pressed sunflower came in at 228°F against ISEO’s 471°F refined high-oleic, and expeller-pressed peanut at 287°F against 446°F refined. The tiers aren’t equal either: a single-sample lab reading beats a producer spec sheet, and both beat a number one blog copied from another.

No mystery why. ISEO says some unrefined oils carry as much as several percent free fatty acids, against under 0.1% once refined, and free fatty acids drive the smoke point down. Refining is what buys the heat.

Why does the same oil show different smoke points?

Mostly free fatty acids. A 2025 study in Foods measured 48 virgin olive oils and found free fatty acid content was the main determinant of the smoke point, with a strong inverse relationship. Refining strips them out, which is why refined oils read higher.

Then there’s the test. ISEO says its values come from a single test per oil, aren’t a statistically valid mean, can be read differently by different analysts, and deserve a prudent margin of safety. It comes down to a person watching for the first wisp.

What a smoke point doesn’t tell you

It tells you when smoke shows up, not how the oil holds up chemically. UC Davis food scientists say olive oil cooks well and that good extra virgin has natural antioxidants that resist heat, even though plenty of neutral oils out-measure it on paper.

Heat does change oil. A 2025 review in Food Chemistry: X describes how thermal oxidation can form aldehydes including acrolein, and notes deep frying typically runs 150 to 190°C, roughly 302°F to 374°F. It links long-term cooking-fume exposure with respiratory risk, so a running hood fan may matter more than the bottle.

Which oil for which cooking method?

Deep frying. FSIS recommends olive, peanut, canola, corn, grapeseed, safflower, sunflower and vegetable oil, and runs chicken pieces at 375°F, fish at 320°F.

Searing and stir-frying. Refined soybean, canola, high-oleic sunflower, peanut or olive. Same oils that work for seasoning a cast iron skillet.

Roasting at 375°F to 425°F. Extra virgin olive oil, canola, vegetable oil.

Dressings and finishing. Extra virgin olive oil, toasted sesame, walnut. Flavor is the whole job, and oil residue is why cleaning a blender without scrubbing is worth learning.

Baking. Vegetable oil, canola, melted coconut oil or butter. Baking rarely pushes oil to its smoke point, so the number barely matters.

Two bottles cover most of home cooking: extra virgin olive oil and one neutral refined oil. A third of toasted sesame earns its space a teaspoon at a time, same small-lever trick as cinnamon or citrus instead of sugar.

Where cooks quietly lose oil quality

Reusing frying oil forever. FSIS says strain it, store it sealed and light-proof up to three months, refrigerate for best quality, and discard it when it clouds, foams or smells off. ISEO adds that extended use raises free fatty acids, lowering the smoke point each round.

Parking the bottle next to the stove. UC Davis says store oil away from light and heat, in a cool dark cabinet. That decorative bottle by the burner is quietly losing quality.

Trusting an avocado oil label. In the first extensive US study of the category, UC Davis found at least 82% of avocado oil samples were stale before their expiration date or mixed with other oils, including three labeled “pure” or “extra virgin” that tested near 100% soybean. FDA has set no standards of identity here, which is how that happens.

Walking away from a hot pan. ISEO puts it bluntly: all oils burn if overheated, and continuous smoke means the fat could ignite. Turn the heat down, don’t add water, stay put.

Sources checked

• ISEO: Food Fats and Oils, Table VIII
• USDA FSIS: Deep Fat Frying
• UC Davis: Olive Oil Myths and Facts
• UC Davis: 82% of Avocado Oil Rancid or Mixed
• Frontiers in Nutrition (2021): smoke points of ten cold-pressed oils
• AOCS Inform (2010): unrefined, extra virgin cold-pressed avocado oil
• Foods (2025): Smoke Point in Virgin Olive Oils
• Food Chemistry: X (2025): Toxic aldehydes in cooking oils

Sources and live links checked July 30, 2026.

Match your oil to your heat, keep a buffer under the number, store the bottle somewhere dark. Two seconds of thought per meal, and it costs nothing.