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Cooking technique
Sweating in cooking is the gentle heating of vegetables in a little oil or butter, with frequent stirring and turning to ensure that any emitted liquid will evaporate. Sweating usually results in tender, sometimes translucent, pieces. Sweating is often a preliminary step to further cooking in liquid; onions, in particular, are often sweated before including in a stew. This differs from sautéing in that sweating is done over a much lower heat, sometimes with salt added to help draw moisture away, and making sure that little or no browning takes place.
The sweating of vegetables has been used as a technique in the preparation of coulis.
In Italy, this cooking technique is known as soffritto, meaning "sub-frying" or "under-frying". In Italian cuisine, it is a common technique and preliminary step in the preparation of risotto, soups and sauces.
"While European cooks start most stews by gently sweating aromatic vegetables such as onions, carrots, celery, and garlic as a gently flavored mirepoix or soffritto, most Indian cooks rely most heavily on onions. And instead of the gentle ..."