Blanching and refreshing is a method of cooking vegetables for 1-2 minutes in boiling water and then cooling them rapidly in iced water. It is chiefly done to set the color before they are added to another dish, such as a terrine or salad. This method is particularly suitable for green vegetables, such as green beans, as their color survives and becomes very intense.
Blanching is also used to precook a large quantity of vegetables, as they can be boiled in advance until nearly tender, refreshed and chilled, and swiftly reheated when required.
The term comes from the French word for whiten and the technique was originally used to remove traces of blood from sweetbreads or brains, leaving them pale, or to boil off the brown skin of almonds.
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