Making fruit spreads—jams, jellies, preserves, conserves, marmalades—allows you to capture the flavor of a favorite fruit in a jar. You need only a handful of ingredients: a sweetener, an acid and, of course, ripe fruit at the peak of its season. The best fruit preserves call for balancing just a few basic ingredients. Here are some guidelines and the key elements needed for making them at home.
Fruit grown from your own trees or backyard garden yields the freshest, purest flavors—and the resulting preserves are all the more rewarding. Farmers' markets are another good place to find high-quality, locally grown fruits. There, you can sample before you buy and ask growers when different varieties will be available.
Underripe fruits contain more pectin and acid, which you need for making fruit preserves, but they can also be less flavorful. For the best balance of flavor and consistency, combine slightly underripe and just-ripe fruits. Most commercially sold fruits are waxed to protect them during shipping and storage. Because the wax coating is not easy to remove, you must often peel the fruits before preserving them, squandering the valuable pectin in their skins. When you grow your own fruit or shop at farmers' markets, you can avoid waxed fruits and achieve better results with your preserves.
Fresh, flavorful herbs and spices—from rosemary to rose hips—can add additional layers of flavor to your preserves. Take care not to add too much, or you'll risk overpowering the fruit.
Pectin is a natural carbohydrate that is concentrated in the skin and seeds of fruit. When combined with the proper ratio of sugar and acid, it causes liquids to jell. Apples and citrus fruits are high in pectin, and they are cooked in many preserves to extract the pectin and help the mixtures thicken.
All fruits contain sugar, but extra sugar is needed in preserves to activate the pectin. Refined white (granulated) sugar is the most common sweetener for fruit preserves because it imparts little flavor and thus will not overpower the flavor of the fruit. You can substitute organic sugar or evaporated cane juice. Some recipes use brown sugar for its subtle caramel flavor. Don't substitute honey, maple or other syrups, or artificial sweeteners for the sugar in the recipes, as their flavor is usually too strong.
A balance of acid and sugar in fruit preserves ensures not only a good set but also a pleasing flavor. Lemon juice works well in most recipes; use Lisbon or Eureka lemons, the most common varieties (Meyer lemons have lower acid). As a rule, 1/4 cup lemon juice per 1 lb. fruit works well, but taste your jam or other preserve to see if it needs more. Too much lemon juice can interfere with the flavor of the fruit. Citric acid, or a combination of citric and ascorbic acid, can also be substituted for lemon juice. Both are available in health-food stores in crystallized form.