Citrus oils are natural essences that are cold-pressed from the rind of the fruit. There are a variety of citrus oils and extracts on the market, including orange, lemon, lime, lemon-lime, tangerine, and grapefruit. It takes 220 oranges, 330 lemons, or 400 limes to make 5 ounces of oil.
Usage: A little citrus oil goes a long way; in some recipes, only a drop or two of oil may be needed to give a substantial boost in flavor. Use about a quarter as much oil as extract; in denser dishes or those with stronger flavors, you may need more. In many dishes, if you have the option, stir in the oil just before serving so that the flavor does not dissipate.
Substitutions: You can substitute citrus oil for citrus extract and vice versa. Given the relative strength of the oil, use about a quarter as much oil as extract. You can also use citrus oil in any recipe that calls for zest.
Availability: Available year round in specialty food markets, or order online.
Storage: Indefinite shelf life when citrus oils are refrigerated.