Tips & Techniques Ingredients All About Citrus

During these cold winter months, when the juicy peaches and plump berries of summer are but a distant memory, this is the season to savor citrus. At their peak of flavor in winter, citrus fruits make a refreshing snack or dessert. The tangy juice and fragrant zest enliven both savory and sweet dishes, from salads and sauces to pies and cakes. It's just what you need to cure the winter blues.

Cooking with Citrus
All citrus fruits are acidic in varying degrees due primarily to the presence of citric acid. This acid packs a powerful punch. That's why a squirt of lemon juice goes a long way toward heightening the taste of foods you're adding more than simply lemon flavor. The acid helps to offset the richness of meats and oils, cleansing the palate and adding a sprightly note to foods. For this reason, citrus is commonly used in Asian cuisines.

You'll discover countless ways to cook with citrus. Brighten vinaigrettes by substituting lemon, orange or other citrus juices for some or all of the vinegar. Add citrus juice to pan sauces for seafood, poultry and pork, infusing them with delicate flavor. (To preserve the fresh taste of the juice, stir it in near the end of cooking.) If a minestrone soup seems bland, squeeze in a bit of lemon juice to boost the flavor.

Try tossing broccoli, spinach, asparagus and other cooked vegetables with melted butter and a spritz of lemon; the acid balances the richness of the butter. A note of caution when combining citrus juices with cooked vegetables: The acid will eventually cause the food to discolor, and you'll wind up with broccoli in an unappetizing shade of dull green. To prevent this, serve the vegetables immediately, or use citrus zest instead of juice, which will add a fresh citrus flavor without causing discoloration.

Citrus juices are often blended into marinades. The acid helps tenderize meat by breaking down the proteins, causing them to unwind, or denature. This same action takes place with ceviche: Raw fish is marinated in citrus (usually lime) juice, which "cooks" the fish. Lemon juice also prevents cut foods like apples and pears from browning again, thanks to the acid.

Citrus zest the colorful portion of the peel is rich in essential oils that add a burst of flavor and aroma. Lemon zest, for example, is a key ingredient in lemon meringue pie and lemon soufflé. A strip of zest tossed in a slow-simmered stew or braised dish imparts a subtle citrus taste. The intensely flavored oils from the zest are also the source of essences, such as lemon oil and orange oil. These bottled oils are often used in baking. When zesting, only the outermost part of the rind should be removed; the white portion just underneath the skin, called the pith, tastes bitter.

Although citrus fruits are most often enjoyed fresh, they can be used in other ways as well. Mediterranean and Middle Eastern cooks preserve lemons in a salt solution. These briny lemons are then added to salads and stews. Classic Moroccan tagines stews of lamb, beef or poultry simmered with a host of spices–often contain preserved lemons, which infuse the dish with an intense lemony tang.

Citrus peel can be candied by simmering it in a sugar syrup, then sprinkling the peel with granulated sugar. Delicious on its own, the candied peel also makes a colorful garnish for ice creams and sorbets.

Selecting and Storing
Choose fruits that feel firm and are heavy for their size, a sign of juiciness. Avoid ones with blemishes or soft spots. Skin color is not necessarily an indicator of quality; oranges, for example, are sometimes dyed.

Most citrus fruits can be stored at room temperature for about a week or in the refrigerator for 3 to 4 weeks. They will be juicier and sweeter if brought to room temperature before serving.