I have recently seen more and more recipes that call for unsalted butter. If I don't happen to have any on hand, is that going to make a difference in the taste or consistency of the dish? —J.I., Mission Viejo, California
Not in a big way. Salt acts as a preservative and adds a little flavor to butter. Lightly salted butter is sometimes called "sweet cream butter" and is best used as a table butter and in general cooking needs.
Unsalted butter, also called "sweet butter", is used mainly for baking. Although unsalted and salted butter may be specifically recommended for cooking or baking particular items, they can generally be substituted for one another.
For comparison purposes, 1 tablespoon of lightly salted butter contains about 105 milligrams of sodium and unsalted butter contains none.
Salted butter has about 1/8 teaspoon salt per stick.