The pecan (/pɨˈkɑːn/, /pɨˈkæn/, or /ˈpiːkæn/), Carya illinoinensis, is a species of hickory, native to south-central North America, in Mexico from Coahuila south to Jalisco and Veracruz, in the United States in Iowa, Illinois, Kansas, Missouri, Indiana, Tennessee, Kentucky, Mississippi, Louisiana, Texas, Oklahoma, Arkansas.
"Pecan" is from an Algonquian word, meaning a nut requiring a stone to crack.
Pecans were one of the most recently domesticated major crops. Although wild pecans were well-known among the colonial Americans as a delicacy, the commercial growing of pecans in the United States did not begin until the 1880s. Today, the U.S. produces between 80% and 95% of the world's pecans, with an annual crop of 150–200 thousand tons from more than 10 million trees. The nut harvest for growers is typically around mid-October. Historically, the leading pecan-producing state in the U.S. has been Georgia, followed by Texas, New Mexico and Oklahoma; they are also grown in Arkansas, Kansas, Missouri, Arizona, South Carolina and Hawaii. Outside the United States, pecans are grown in Australia, Brazil, China, Israel, Mexico, Peru and South Africa. They can be grown approximately from USDA hardiness zones 5 to 9, provided summers are also hot and humid.
Pecan trees may live and bear edible seeds for more than 300 years. They are mostly self-incompatible, because most cultivars, being clones derived from wild trees, show incomplete dichogamy. Generally, two or more trees of different cultivars must be present to pollinate each other.
Before European settlement, pecans were widely consumed and traded by Native Americans. As a food source, pecans are a natural choice for preagricultural society. They can provide two to five times more calories per unit weight than wild game, and require no preparation. As a wild forage, the fruit of the previous growing season is commonly still edible when found on the ground. Hollow tree trunks, found in abundance in pecan stands, offer ideal storage of pecans by humans and squirrels alike.
Pecans first became known to Europeans in the 16th century. The first Europeans to come into contact with pecans were Spanish explorers in what is now Mexico, Texas, and Louisiana. The genus Carya does not exist in the Old World. Because of their familiarity with the genus Juglans, these early explorers referred to the nuts as nogales and nueces, the Spanish terms for "walnut trees" and "fruit of the walnut." They noted the particularly thin shell and acorn-like shape of the fruit, indicating they were indeed referring to pecans. The Spaniards took the pecan into Europe, Asia, and Africa beginning in the 16th century. In 1792, William Bartram reported in his botanical book, Travels, a nut tree, Juglans exalata that some botanists today argue was the American pecan tree, but others argue was hickory, Carya ovata. Pecan trees are native to the United States, and writing about the pecan tree goes back to the nation's founders. Thomas Jefferson planted pecan trees, Carya illinoinensis (Illinois nuts), in his nut orchard at his home, Monticello, in Virginia. George Washington reported in his journal that Thomas Jefferson gave him "Illinois nuts", pecans, which George Washington then grew at Mount Vernon, his Virginia home.
The pecan tree is a large deciduous tree, growing to 20–40 m (66–130 ft) in height, rarely to 44 m (144 ft); taller trees to 50–55 m (160–180 ft) have been claimed but not verified. It typically has a spread of 12–23 m (39–75 ft) with a trunk up to 2 m (6.6 ft) diameter. A 10-year-old sapling will stand about 5 m (16 ft) tall. The leaves are alternate, 30–45 cm (12–18 in) long, and pinnate with 9–17 leaflets, each leaflet 5–12 cm (2.0–4.7 in) long and 2–6 cm (0.79–2.4 in) broad. The flowers are wind-pollinated, and monoecious, with staminate and pistillate catkins on the same tree; the male catkins are pendulous, up to 18 cm (7.1 in) long; the female catkins are small, with three to six flowers clustered together.
A pecan, like the fruit of all other members of the hickory genus, is not truly a nut, but is technically a drupe, a fruit with a single stone or pit, surrounded by a husk. The husks are produced from the exocarp tissue of the flower, while the part known as the nut develops from the endocarp and contains the seed. The husk itself is aeneous, oval to oblong, 2.6–6 cm (1.0–2.4 in) long and 1.5–3 cm (0.59–1.2 in) broad. The outer husk is 3–4 mm (0.12–0.16 in) thick, starts out green and turns brown at maturity, at which time it splits off in four sections to release the thin-shelled nut.
The seeds of the pecan are edible, with a rich, buttery flavor. They can be eaten fresh or used in cooking, particularly in sweet desserts, but also in some savory dishes. One of the most common desserts with the pecan as a central ingredient is the pecan pie, a traditional southern U.S. recipe. Pecans are also a major ingredient in praline candy, most often associated with New Orleans.
In addition to the pecan seed, the wood is also used in making furniture and wood flooring, as well as flavoring fuel for smoking meats.
Advantage of Pecan
Pecans have it all. Besides being one of the most elegant, versatile and rich-tasting nuts you can put on your plate, they offer up a package of health benefits that's hard to beat. The new 2005 Dietary Guidelines from the U.S. Department of Agriculture say that eating 4 to 5 servings of nuts each week (and that includes pecans) will bring you one step closer to putting your diet in line with current healthy eating recommendations.
Though the research proving pecan's tremendous health benefits may be recent, pecan-producing trees dotted the landscape long before the discovery of the "New World" and enriched the diets of the native tribes living in the central and southern regions of the United States. Today, pecans are available from coast to coast and experts have confirmed the bevy of benefits pecans have to offer.
Though the research proving pecan's tremendous health benefits may be recent, pecan-producing trees dotted the landscape long before the discovery of the "New World" and enriched the diets of the native tribes living in the central and southern regions of the United States. Today, pecans are available from coast to coast and experts have confirmed the bevy of benefits pecans have to offer.
Blood Pressure
While eating pecans and other nuts can't cure high blood pressure, they are an important part of the DASH (Dietary Approaches to Stop Hypertension) eating plan, developed by the National Institutes of Health. The DASH diet also falls right in line with the new 2005 U.S. Dietary Guidelines for healthy eating issued by the Department of Health and Human Services and the Department of Agriculture. Research has shown that following the DASH diet is an effective way to lower blood pressure, while supercharging your diet with much needed nutrients. One part of the DASH dietary prescription? Eat 4 to 5 servings (1 ½ oz each) of pecans a week.
Breast Cancer
Pecans are a rich source of oleic acid, the same type of fatty acid found in olive oil. Researchers from Northwestern University in Chicago recently found in laboratory tests that oleic acid has the ability to suppress the activity of a gene in cells thought to trigger breast cancer. While this area of study is still in its early stages, the researchers say it could eventually translate into a recommendation to eat more foods rich in oleic acid, like pecans and olive oil. A one-ounce serving of pecans provides about 25% more oleic acid than a one-tablespoon serving of olive oil.
Heart Health
Researchers from Loma Linda University in California and New Mexico State University in Las Cruces, New Mexico, have confirmed that when pecans are part of the daily diet, levels of "bad" cholesterol in the blood drop. Pecans get their cholesterol-lowering ability from both the type of fat they contain and the presence of beta-sitosterol, a natural cholesterol-lowering compound. Eating 1 ½ ounces of pecans a day (27 to 30 pecan halves), when its part of a heart-healthy diet, can reduce the risk of heart disease.
Prostate Health
The same natural compound that gives pecans its cholesterol-lowering power, has also been shown to be effective in treating the symptoms of benign prostatic hyperplasia (BPH), a non-cancerous enlargement of the prostate gland in men. About two ounces of pecans provides a dose of beta-sitosterol found to be effective. In addition, a recent laboratory study from Purdue University found that gamma-tocopherol, the type of vitamin E found in pecans, has the ability to kill prostate cancer cells while leaving healthy cells alone. The researchers now want to test this and other types of vitamin E in animals.
Weight Control
Contrary to the widely held, but mistaken belief that "nuts are fattening," several population studies found that as nut consumption increased, body fat actually decreased. And clinical studies have confirmed that conclusion, finding that eating nuts actually resulted in lower weights. One study from Harvard School of Public Health discovered that people following a weight-loss diet that contained 35% of calories from fat, including pecans as a fat source, were able to keep weight off longer than people following a traditionally recommended lower fat diet. With their super nutrition profile and low-carb content, pecans also make a perfect choice for people following low-carb weight-loss plans.
Pecans and other nuts count as meat servings in the Food Pyramid. That's because pecans are high in protein and other important nutrients.
However, nuts contain more healthful types of fats than meat does and they are cholesterol-free, so they make excellent choices over fatty meats like steak or even chicken.
In general, ½ ounce of nuts (10 pecan halves) can take the place of 1 ounce of meat in your diet. Though the recommended number of servings you should get from the meat (and beans) group varies depending upon your age, whether you're male or female and how active you are, the average person should aim for 5 ½ servings from this group each day.
Because of research showing that the saturated fat found in meat can increase the risk for heart disease, the Pyramid recommends that you frequently choose nuts and beans over meat. That doesn't mean you can't have pecans as snacks, but if you're eating according to the Pyramid, just keep in mind that pecans and other nuts take the place of meat in your diet plan.
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