Desifact — Cooking Fat Smoke Points | desifact.com
Four steps from a block of butter to a fat that smokes at 250 °C and survives deep frying at about 200 °C.
Ghee is made by simmering butter, skimming the impurities off the surface, pouring off the clear fat and discarding the solids that settle at the bottom. Those four actions are the whole method.
Simmer the butter gently. Water cooks off and the milk solids begin to separate: some float as foam on the surface, the rest sink as sediment.
Skim the impurities from the surface while the fat is still liquid. Then pour off the clear fat, leaving the settled solids behind, and discard those solids — they are what burns first in a hot pan.
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The result is clarified butter with a 250 °C (482 °F) smoke point, the same value as beef tallow and mustard oil. Typical deep frying runs at about 200 °C (392 °F), so ghee clears the line by 50 °C.
That margin is why ghee survives deep frying while plain butter does not: unrefined butter smokes at 150 °C, 50 °C below the frying temperature, because its milk solids are still present.
The finished fat keeps indefinitely without those solids and water, and its ceiling of 250 °C leaves headroom even when the pan runs hotter than ordinary frying.
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