Butter is not pure fat; it is also composed of water and of milk solids that are soluble in water. When the water is evaporated by boiling, these solids precipitate, and the oil or ghee remains.
To make ghee, heat unsalted butter in a saucepan until it boils; then lower the heat. When the white foam of milk solids that will accumulate on the top begins to collapse and thicken, start skimming it off. Do not disturb the bottom of the pan, as some of these solids will also sink and can be left in the pot until the ghee is poured off.
As the butter continues to boil, watch the oily portion to see when it becomes clear, and watch the sediment on the bottom to see when it becomes a golden brown. Don't let this scorch and ruin the ghee.
When all the water is evaporated, the sound of the cooking will change from one of boiling to one of frying, and the bubbling will stop. When only the clear, hissing oil and the golden sediment remain, the ghee is ready. At this point, the temperature will begin to rise quickly, so remove the pan from the heat, and let it sit for a moment. During this time, the hot fat will turn the sediment a little darker.
Pour the ghee off into an earthenware, glass, or metal container for use near the stove. Scrape out the sediments and refrigerate them with the skimmings, to add when cooking vegetables, sauces, or breads.
From "Transition to Vegetarianism", by Rudolph Ballentine, M.D.Himalayan International Institute, 1987
Copyright 2004 West-Art, Prometheus 91/2004
PROMETHEUS, Internet Bulletin for Art, News, Politics and Science, Nr. 91, Spring 2004