Sweet Potato

Description
Sweet potatoes are a Native American plant that was the main source of nourishment for early homesteaders and for soldiers during the Revolutionary War. These tuberous roots are among the most nutritious foods in the vegetable kingdom. They are excellent sources of vitamins A and C. This is why one colonial physician called them the "vegetable indispensable." Sweet potatoes are often confused with yams, but yams are large, starchy roots grown in Africa and Asia. Yams can grow up to 100 pounds and are rarely available in American supermarkets. Nutritionally, sweet potatoes greatly outweigh yams. Because of the common use of the term "yam," it is acceptable to use this term when referring to sweet potatoes. Sweet potatoes contain an enzyme that converts most of its starches into sugars as the potato matures. This sweetness continues to increase during storage and when they are cooked.

Selection
Choose firm, dark, smooth sweet potatoes without wrinkles, bruises, sprouts, or decay. Even if cut away, a decayed spot may have already caused the whole potato to take on an unpleasant flavor.

Storage
Sweet potatoes spoil rapidly. Sweet potatoes should be stored in a cool (55°F to 60°F) dry place, never in the refrigerator. Kept at 55°F, sweet potatoes can be kept for a longer time than if stored at room temperature. Do not store them in the refrigerator, where they will develop a hard core and an "off" taste.

If stored properly, sweet potatoes will keep for a month or longer. At normal room temperature, they should be used within a week of purchase. You may brush off any excess dirt before storing, but do not wash them until you are ready to cook them. It is the moisture from washing that will increase their spoilage.

Varieties
Although sweet potatoes are harvested in August through October, they are available in supermarkets all year. Many stores feature them at Thanksgiving and Christmas. There are two varieties of sweet potatoes; the pale yellow with a dry flesh and the dark orange with a moist flesh. The dark orange variety is plumper in shape and somewhat sweeter than the yellow variety.

Preparation
Wash sweet potatoes well. Cook them whole whenever possible as most of the nutrients are next to the skin, and skins are easier to remove after they have been cooked. Pierce skin with fork. Place potatoes in a pan and cook in an oven heated to 375° F for about 45 minutes or until tender. Cool potatoes slightly before removing skins. Sweet potatoes can be cooked in a microwave oven to save time. Wash and pierce potatoes, then place them on a paper towel. The cooking time for 2 medium potatoes is on high for 5–9 minutes, and 4 potatoes, 10–13 minutes. Yellow and dark orange sweet potatoes can be used interchangeably in recipes. Try not to mix the two types in a single dish, because their different textures and cooking times may affect the outcome of the recipe. The yellow variety takes longer to cook than the orange and will be done at the upper range of cooking times.

Uses & Tips
Before cooking, scrub sweet potatoes thoroughly to remove any dirt.

Sweet potatoes may be baked, boiled, steamed, or microwaved. They may be used in soups or in baked goods such as sweet potato pie or sweet potato bread.

Cinnamon, brown sugar, grated lemon or orange rind, raisins, drained canned pineapple, or nuts may be added for flavor.

Mashed sweet potatoes may be used in recipes calling for pumpkin puree.

Baking
Pierce the potatoes with a fork before baking to let the steam escape. To speed clean up, place potatoes on a foil-lined baking sheet to catch juices that escape during cooking. Cooking time: 30 to 60 minutes in a 400°F oven, depending on size.

Boiling
If cooked whole, sweet potatoes do not need to be peeled. The skins will slip off easily when they are done, leaving most of the nutrients intact. The skin is edible, however, and supplies additional dietary fiber. Cooking time: for whole potatoes, 15 to 35 minutes; for chunks, 10 to 15 minutes.

Microwaving
Pierce potatoes several times with a fork and place on a paper towel. After taking potatoes out of the microwave, wrap in foil and let stand five to ten minutes. Cooking time: for two medium potatoes, five to nine minutes; for four, 10 to 13 minutes.

Source

 * Sweet Potatoes, Fresh by the US Department of Agriculture, public domain government resource -- original source of article
 * Vegetable of the Month: Sweet Potato by the US Centers for Disease Control and Prevention, public domain government resource -- source of additional material & pictures

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