WHAT IS THE DIFFERENCE BETWEEN A SWEET POTATO AND A YAM?

Several decades ago when orange flesh sweet potatoes were introduced in the southern United States producers and shippers desired to distinguish them from the more traditional white flesh types. The African word "nyami" referring to the starchy, edible root of the Dioscorea genus of plants was adopted in its English form, "yam". Yams in the U.S. are actually sweet potatoes with relatively moist texture and orange flesh. Although the terms are generally used interchangeably, the U.S. Department of Agriculture requires that the label "yam" always be accompanied by "sweet potato." The following information outlines several differences between sweet potatoes and yams.


FACTORSWEET POTATOYAM
Scientific name Ipomoea batatasDioscorea Species
Plant family Morning glory
CONVOLVULACEAE
Yam
DIOSCOREACEAE
Plant groupDicotyledonMonocotyledon
Chromosome number2n=90 (hexaploid)2n=20
Flower characterMonoeciousDioecious
Historical beginning
(Peru, Ecuador)
Prehistoric50,000 BC
Edible storage organStorage rootTuber
Number/plant4-101-5
AppearanceSmooth, with thin skinRough, scaly skin
ShapeShort, blocky,
tapered ends
Long, cylindrical,
some with "toes"
Dry matter22-28%20-35%
Mouth feelMoist*Dry
TasteSweet*Starchy
Beta carotene (Vitamin A)High (orange varieties) * Very low
PropagationTransplants/vine cuttingsTuber pieces
Growing season90-150 days180-360 days
Climatic requirementsTropical and temperate Tropical
AvailabilityGrown in USAImported from Caribbean
*Characteristic of most sweet potato varieties grown in the U.S.

The versatile sweet potato is ideal fare for the health - conscious food consumer. With the ever-growing interest in health and natural foods, the sweet potato is quickly finding its place in the family weekly diet the year around. The sweet potato blends with herbs, spices and flavorings producing delicious dishes of all types. From processed baby foods to the main dishes, casseroles, salads, breads and desserts, sweet potatoes add valuable, appetizing nutrients and color to any meal.

As a main dish or prepared as a dessert, the sweet potato is a nutritious and economical food. One baked sweet potato (3 1/2 ounce serving) provides over 8,800 IU of vitamin A or about twice the recommended daily allowance, yet it contains only 141 calories making it valuable for the weight watcher. This nutritious vegetable provides 42 percent of the Recommended Daily Allowance (RDA) for vitamin C, 6 percent of the RDA for calcium, 10 percent of the RDA for iron, and 8 percent of the RDA for thiamine for healthy adults. It is low in sodium and is a good source of fiber and other important vitamins and minerals. A complex carbohydrate food source, it provides beta carotene which may be a factor in reducing the risk of certain cancers.

For the most food value, choose sweet potatoes of a deep orange color.

When buying sweet potatoes, select sound, firm roots. Handle them carefully to prevent bruising. Storage in a dry, unrefrigerated bin kept at 55-60 degrees F. is best. DO NOT REFRIGERATE, because temperatures below 55 degrees F. will chill this tropical vegetable giving it a hard core and an undesirable taste when cooked.

Wash cured sweet potatoes and bake or boil until slightly soft. If boiled, drain immediately. Thoroughly cool the baked or boiled sweet potatoes. Wrap individually (skins left on) in freezer film or foil and place in plastic freezer bags. Seal, label and freeze.

Most sweet potato dishes freeze well. Save time and energy by making a sweet potato dish to serve and one to store in the freezer.

Helpful Hints:

Sweet potatoes can be baked, boiled, fried, broiled, canned or frozen. They can also be cooked in the microwave oven.

Before cooking sweet potatoes, scrub skin and trim off any bruised or woody portions.

If you are cutting calories, serve a plain sweet potato, cut down on margarine or butter and use skim milk or unsweetened orange juice as liquid when you prepare mashed sweet potatoes.

Remember, it is what you add to the sweet potato that increases calories.
1 small, baked in skin ...............................141 calories
3 1/2 ounces, candied................................168 calories
3 1/2 ounces, canned, syrup pack.........114 calories

A freshly baked or boiled sweet potato is delicious and nutritious. You need only to add a pat of butter or serve it plain. Don't feel that you must add high-calorie ingredients to make the sweet potato acceptable.

Rub a little fat or oil over clean and dry sweet potatoes of uniform size. Place on baking sheet and bake at 400 degrees F. until soft, 30 to 50 minutes, depending on size. Sweet potatoes that are greased before baking peel easily.

Boiled Sweet Potatoes: Drop clean sweet potatoes into enough boiling water to cover them. Cover pan and return water to boiling as quickly as possible. Lower heat and cook until tender. Drain at once. Peel and season with butter and salt to taste. Use 1 medium sweet potato per person. Boiled sweet potatoes can be used for pies, cookies, casseroles, glazed, candied or frozen.

Deep Fat French Fried Sweet Potatoes: Pare and cut into length-wise strips, about 1/2 inch thick. Heat oil in fryer to 365 degrees F. Keep fry basket in fat as it heats.

Raise basket and add enough sweet potato strips to cover bottom of basket. Lower basket slowly into hot fat. If fat bubbles much, lift and lower basket until bubbling subsides. Fry until sweet potato strips are brown and tender. Remove from hot oil and drain onto paper towels. Sprinkle with salt, if desired. Spread sweet potatoes on baking sheet and place in a warm oven while others are being cooked.

Charcoal Broiled Sweet Potatoes: Rub a little fat over clean sweet potato skins. Wrap double foil loosely around sweet potatoes. Cook in coals for about 45 minutes. Keep warm on edge of grill.

Skillet Sweet Potatoes: In large deep skillet, heat 1 1/2 inch deep vegetable oil to 365 degrees F. Add sweet potato strips to cover bottom of skillet; fry 5 minutes or until brown and tender. Remove from hot oil and drain on paper towels. Sprinkle with salt or powdered sugar.

Microwave Sweet Potatoes: For best results, choose uniform size sweet potatoes. Pierce washed sweet potatoes with a fork. Place on paper towel on shelf of microwave oven 1 inch apart. Turn sweet potatoes over and rearrange after half of cooking time. Cook on HIGH power level. Cooking time will vary, depending on the number of sweet potatoes.

Sweet PotatoesMinutes
14 to 6
26 to 8
38 to 12
412 to 16
516 to 20
Sweet potatoes may still feel firm when done. Let stand 5 minutes to soften.

Candied Sweet Potatoes

6 medium sweet potatoes
1/2 cup sugar
1/4 cup water
3 tablespoons butter

Scrub sweet potatoes thoroughly. Drop them in enough boiling salted water to cover sweet potatoes. Cover pan. Lower heat and cook 15 to 20 minutes. Drain; peel sweet potatoes and cut into 1/2 inch slices. Put into buttered baking dish. Combine sugar, water and butter. Boil 2-3 minutes, then pour over cooked, sliced sweet potatoes. Bake at 350 degrees F. for about 30 minutes or until lightly brown. Spoon syrup over sweet potatoes several times while baking. Lemon juice or lemon slices on top of sweet potatoes while baking will improve flavor and help retain their bright color. Yield: 6 servings

SWEET POTATO BUTTER

2 Garlic cloves
Freshly ground Pepper to taste
2 Sweet Potatoes
Fine Sea Salt to taste
2 medium Carrots
2 Tablespoons chopped Parsley
1/2 to 3/4 Cup Vegetable broth
2 Tablespoons chopped Cilantro (Optional)
1 Tablespoon extra-virgin Olive Oil


Put unpeeled garlic cloves on aluminum foil and bake at 350 degrees F. in oven or toaster oven for about 10 minutes, until soft.

Microwave or boil unpeeled potatoes until done. Peel carrots, cut into large chunks and microwave or boil until soft.

Drain carrots, peel potatoes and put both in a food processor. Squeeze in the baked garlic. Add 1/2 cup broth and blend. With motor running, add oil and keep blending, adding more broth until puree is fairly smooth and full.

Add salt and pepper to taste. Dip can be made as long as a day in advance, covered and refrigerated. Bring to room temperature for serving and stir in the optional herbs right before serving with raw vegetables and bread sticks.

Makes 6 servings.

SWEET POTATO PECAN PIE (Makes one 9-inch pie)

1 (9 - inch) unbaked pastry shell
1 pound (2 medium) sweet potatoes (yams!), cooked and peeled
1/4 cup margarine or butter
1 (14 - ounce) can Eagle Brand Sweetened Condensed Milk, (NOT evaporated milk)
1 teaspoon grated orange rind
1 teaspoon vanilla extract
1 teaspoon ground cinnamon
teaspoon ground nutmeg
1/4 teaspoon salt
2 eggs
Pecan Topping

Preheat oven to 350 degrees F. In large mixer bowl, beat hot sweet potatoes with margarine until smooth. Add remaining ingredients except pastry shell and Pecan Topping; mix well. Pour into pastry shell. Bake 30 minutes. Remove from oven; spoon Pecan Topping evenly over top. bake 20 to 25 minutes longer or until golden brown. Cool. Serve warm or chilled. Refrigerate leftovers.

Pecan Topping: In small mixer bowl, combine 1 egg, 3 tablespoons dark corn syrup, 3 tablespoons firmly packed light brown sugar, 1 tablespoon margarine or butter, melted, and teaspoon maple flavoring; mix well. Stir in 1 cup chopped pecans.