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POTATO. The potato is a tuber—a short, thick, underground stem with stored starches and sugars—of the potato plant. It was given its botanical name, Solanum tuberosum, in 1596 by the Swiss botanist Gaspard Bauhin, and belongs to the Solanaceae family, the nightshades, which includes eggplant, peppers, and the tomato. (The sweet potato is not a potato; it belongs to the morning glory family.) Growing wild as early as 13,000 years ago on the Chilean coast of South America, potatoes were first cultivated by farmers in the Andes Mountains nearly seven thousand years ago.

Nutritionally, the potato supplies complex carbohydrates—essential for energy—and a very low amount (about 10 percent) of protein. One serving (a 5.3-ounce medium potato) provides: 45 percent of Recommended Daily Intake (RDI) for vitamin C (most of it in the millimeters-thick layer immediately under the skin), 21 percent of potassium, 3 grams of fiber, essentially no fat, and only 100 calories. It is rich in the minerals iron and magnesium and supplies all the vital nutrients except calcium and vitamins A and D.

Potatoes are the vegetable eaten most frequently in the United States, and the one ordered most when Americans eat out. In 2001, the average American ate 41 pounds of potatoes. In 1996, the annual per capita consumption increased with age among those over eighteen: between eighteen and thirty-four, 74.3 pounds; thirty-five to forty-four, 80.6; forty-five to fifty-four, 87.4; fifty-five to sixty-four, 88.9; and, for those sixty-five and older, 109 pounds. Interestingly, consumption again peaked among those between thirteen and seventeen (83.2 pounds) and six to twelve (85.5 pounds), who presumably consume most of their potatoes as french fries, chips, and novelty forms.

The United States ranks fourth in world potato production, with an estimated 1.26 million acres planted in 2001. Russia is the largest producer. With a world harvest of 291 million tons grown in more than 100 countries, potatoes are second only to rice as a world food crop.

South American Origins

The potato was domesticated high in the Andes Mountains in South America by 3000 B.C.E., but it was not until the Incan civilization (ca. 100–1530 C.E.) that the tuber's true agricultural potential was realized. The climatic challenges of growing crops in the heights of the Andes are formidable. Radical swings in temperature, from highs of 62°F (17°C) to lows below freezing (most nights of the year), occur even within a twenty-four-hour period, and constantly disrupt the potato plant's physiological processes. Yet, potatoes are ideally suited to these conditions; the plant grows in even the poorest soils, and the hardiest species can survive at an altitude of 15,000 feet.

The Inca devised agricultural innovations that maximized the potato crop. The introduction of terracing enabled steep slopes to be planted. A system of canals efficiently distributed water from higher in the mountains to each terrace level. In the absence of plows and oxen, a wooden foot plow called a taclla was invented that is still used in the Andes today. A representation of this tool is found in a Spanish woodcut from the late sixteenth or early seventeenth century (but the tool is presumed to predate that). The Inca wisely prized agricultural diversity, growing 3,000 varieties of potatoes in various sizes, textures, and colors. Their goal was to develop a different kind of potato for every type of soil, sun, and moisture condition. Thus, the rulers could secure a high yield of potatoes—enough to feed thousands of members of the expanding empire—from disproportionately small plots of land.

The Inca also serendipitously discovered how to freeze-dry potatoes. At night, the cold of the Andes froze the tubers. (Raw potatoes are 80 percent water.) During the day, however, they thawed in the warmth of the sun. As they defrosted, laborers stamped on them to press out all the moisture. After several days of alternating freezing and defrosting, the potatoes were dehydrated and transformed into a lightweight, transportable substance known as chuno. Stored in sealed, permanently frozen underground storehouses, the freeze-dried potatoes kept for five or six years. When needed for sustenance during the lean months, the chuno could be reconstituted by soaking in water, then being cooked or ground into meal, with no loss of nutritional value. Chuno was so precious to the Inca that it was used as currency and collected as tribute. It was also believed that potatoes have healing properties. Raw slices were placed on broken bones, aching heads, and rubbed on bodies to cure skin diseases, and slices were carried to prevent rheumatism

From South America to Europe

When the Spanish arrived in South America around 1537, they were not impressed by the potato. The strange tubers, misshapen and bitter, were about the size of peanuts, and bore little resemblance to potatoes we know today. The Spanish mistook them for a kind of truffle, calling them tartuffo. The Inca routinely consumed the choice, large tubers, and planted only the rejects, thereby propagating progressively inferior tubers.

Gradually, the Spanish realized that potatoes were perfect food for sailors on ships returning from Peru. The tubers traveled well, were cheap, nutritious, required little preparation, and prevented scurvy. Returning to Spain by way of sub-Saharan Africa, the Spanish introduced potatoes there in 1538. Leftovers from shipboard food found their way to Spain in the 1550s but, in most areas, they did not grow well and were not popular. Still, as early as 1570, potatoes could be purchased in markets in Seville, and, by 1573, they were being fed to hospital patients in other parts of Spain.

Through the first half of the seventeenth century, potatoes were eaten primarily by the poor and soldiers in Spain. In 1653, however, the historian Bernabé Cobo made a laudatory reference to the culinary properties of chuno, describing how Spanish women were able to grind the substance into more white flour than could be obtained from wheat, and from which they made sponge cakes and pastries with almonds and sugar.

Not until 1760 did Spanish plant breeders start to improve the potato. Eventually, it was found that potatoes grew well in the mountainous Pyrenees and along the Atlantic coast, where they were popular among Basque fishermen during their voyages to the Grand Banks of Newfoundland.

The Potato Diaspora

From Spain, potatoes spread to all parts of Europe. Spanish ships carried the vegetable to Italy around 1560, making that country the first after Spain to eat potatoes on an appreciable scale. Potatoes also traveled along the "Spanish road" that connected Spain's imperial provinces in northern Italy with the Low Countries.

By 1600, the potato had entered Austria, Belgium, Holland, France, Switzerland, England, Germany, and, most likely, Portugal and Ireland. Some historians claim that it was Basque fishermen who first brought potatoes to Ireland, when they came ashore to dry their catches on their return voyages from Newfoundland. Others maintain it was Sir Walter Raleigh who planted the first potatoes on his estate in Ireland. The potato was introduced in India, possibly as early as 1615, and had reached the most remote parts of China by 1643. Beginning about 1730, the Scottish Highlands adopted potatoes as completely as Ireland had.

Fear of Potatoes

It is not unusual for new foods to be met with skepticism and fear, especially those arriving from a strange, faraway continent where they are consumed by "uncivilized" non-Christian peoples. The potato, however, had a tougher battle for acceptance than many other foodstuffs introduced from the Americas. Aside from its odd, unaesthetic appearance and initially bitter taste, the tuber was feared for a variety of reasons. Since it was not mentioned in the Bible, it was often associated with the devil. As a consequence, in the north of Ireland and in Scotland, Protestants flatly refused to plant them. In Catholic Ireland, to be on the safe side, peasants sprinkled their seed potatoes with holy water and planted them on Good Friday.

Another source of prejudice against the potato was its membership in the nightshade family, which includes a number of poisonous members: deadly nightshade (belladonna, which is poisonous), mandrake (known as a soporific and fertility drug), tobacco, and henbane (poison). Some of these substances have traditionally been associated in various cultures with magic and witchcraft. In many folk beliefs there is a grain of truth. Solanine, contained in the tubers and common to all plants in the nightshade family, is indeed a poison. Unlike modern potatoes, which contain only a nonharmful trace amount, tubers of the sixteenth and seventeenth centuries had much higher levels, not enough to cause death, but sometimes a rash appeared. That led to its association with the deadliest disease of the time, leprosy. So great was the fear that, when Frederick the Great of Prussia ordered his people to plant potatoes in 1744, they pulled them up. Frederick was forced to post soldiers to guard the crops. Ten years later, in 1754, the king of Sweden also ordered his subjects to grow potatoes. Yet, when famine struck Kolberg in 1774, wagonloads of potatoes sent by Frederick were rejected.

All over Europe, it was believed that the potato plant would bring disease. In the seventeenth century, the parliaments of Franche Compté and adjacent Burgundy actually prohibited its cultivation. In the early nineteenth century, Ludwig Feuerbach and other German radicals believed that "potato blood" was weakening the people and delaying the anticipated revolution. In Sicily, potatoes were used like voodoo dolls: the name of an enemy was attached to a tuber and buried in the belief that this would ensure his or her death. Even as late as 1928 in America, Celestine Eustis, the author of Cooking in Old Creole Days, advised readers to throw out the water in which potatoes had been boiled because it was poisonous.

At the same time potatoes were feared and reviled, and being grown only in the gardens of botanists, there was also a developing literature in sixteenth-century European herbal books asserting that potatoes had some therapeutic effects. Among the diverse claims were enhanced sexual desire, fertility, and longevity, and cures for diarrhea, tuberculosis, and impotence.

The Potato in Time of War

Europeans quickly discovered that the potato afforded them a military advantage; it was ideally suited to combat starvation caused by war. During the Dutch Wars (1567–1609), for example, Spanish soldiers crossed the Alps on foot from Italy, marching north through Franche Compté, Alsace, and the Rhinelands. Villagers along the route quickly discovered that tubers carried by the soldiers could be planted, hidden underground, and dug as needed, unlike grain. Nearly every military venture after about 1560, including World War II, resulted in more acreage being planted in potatoes.

When French, Austrian, and Russian armies invaded Prussia during the Seven Years War (1756–1763), peasants escaped starvation by eating potatoes. As a result, the Austrian, Russian, and French governments all persuaded their own peasants to grow potatoes. In 1778, the War of the Bavarian Succession was called "the potato war" because most of the action consisted of destroying the enemy's food supplies.

In Russia, crop failure in 1838–1839 convinced people in central and northern parts of the country to raise potatoes. In the course of the nineteenth century, potatoes displaced bread as the principal food for poorer classes from Belgium to Russia. They were cheaper than bread, required less preparation, and were just as nutritious.

Potatoes in England

Potatoes appeared in the British Isles in the 1590s. The historical record is unclear about which of two famous explorers introduced them, Sir Francis Drake or Sir Walter Raleigh. Regardless, the first English potatoes did not, contrary to popular myth, originate in Virginia. This mistaken notion gained credence because the first tubers destined for England passed through Virginia after having been taken aboard in South America.

The tubers were not immediately embraced in Great Britain, remaining a garden crop grown by botanists until 1780. The English, traditionally not fond of vegetables, based most of their meals on meat, and the potato carried a social stigma as the food of savages and peasants. The earliest potato crops in England were produced to feed sailors. By 1700, a stew called lobscouse, consisting of potatoes, meat, onions, and strong seasonings, was recorded in Lancashire. When hardtack was added as an accompaniment, lobscouse became the standard dish of choice for shipboard crews. Yet, the tuber was so despised during the reign of George III (reigned 1760–1820) that it took years of botanical experiments before the English conceded that potatoes might be acceptable as cattle feed.

In the 1700s, northwest England began to produce an abundance of potatoes, as many as 13.5 tons per acre. Cultivation occurred, too, in Cornwall and outside London, where industry was beginning. In many ways, the potato fueled the Industrial Revolution; it was good, cheap food for another lowly multitude—workers. This trend was also generated by the simultaneous decline in bread production. In 1832, the Bread Acts were rewritten so potato flour could be used without losing the right to call the product "bread." By 1836, two million people who used to subsist on wheat flour—one-seventh of the population—were living chiefly on potatoes. By 1850, Londoners were consuming 3,000 tons of potatoes a week. Baked potatoes played a special role in London working-class life—they were sold by street vendors both to eat and to use as hand warmers.

The perennial British working-class favorite, fish and chips, reached the streets as two separate dishes, with fish coming at least thirty years before chips. Neither was fried in deep fat until the 1860s. By 1888, there were between 10,000 and 12,000 fish-and-chips shops in the United Kingdom serving the duo wrapped in newspaper and sprinkled liberally with vinegar.

Meanwhile, the elite consumed potatoes in very different forms—disguised as other foods. Unadulterated, naked potatoes were not considered appropriate food for the upper classes, and Queen Victoria's chef carved the tubers into shapes like olives and pears, or buried them entirely in purées and soups. By 1914, however, people in England said they would rather pass up greens, butter, and nearly all their precious meat before they would give up potatoes—quite a change of heart. It was the English who coined the word "spud" for potato, a slang expression that originally referred to a potato-digging spade.

The Great Irish Potato Famine

Ireland was the first country in Europe to accept the potato as a field crop, in the seventeenth century, and to embrace it as a staple in the eighteenth. To the poverty-stricken peasantry, this tuber was a safeguard against unemployment, overpopulation, crop failure, and starvation. Landless laborers rented tiny plots that they sowed with potatoes. One acre could feed a family of six, averaging ten pounds of potatoes per person a day. Potatoes did not replace meat immediately, but other staples like oats, beans, barley, herring, and bread gradually disappeared from the table. Over time, the diet shifted to one of boiled potatoes supplemented by milk, which supplied calcium and vitamins A and D, making the meal nutritionally complete.

As early as 1740, the potato saved Ireland from famine. Between 1780 and 1841, when the potato achieved its dominance, the population doubled in Ireland. According to historic sources, it cannot be said with certainty that the potato was responsible, but surely it played a role. By 1845, about 40 percent of the Irish population was dependent on the tubers raised on 65,000 farms of not more than one acre each. Potatoes were also used to feed pigs.

In 1845, blight struck potato fields throughout Europe, but those most devastatingly affected by the fungus Phytophthora infestans were in Ireland. The assumption is that the blight was carried back by ship from North America on a diseased tuber. Livid purple patches appeared, covering whole potato plants—roots, tubers, and foliage—after which they turned brown and rotted. Whole fields went under in a matter of hours, destroying 40 percent of the crop. Yet, few deaths occurred because many people slaughtered their pigs, which normally ate a third of the crop. In 1846, the blight redoubled, killing 90 percent of the potatoes and preventing a new crop from being sown. The fungus was not as virulent in 1847, but reappeared in full force in 1848–1849. About five to six months later, famine set in, and diseases including typhus, dysentery, relapsing fever, respiratory infections, and cholera were not far behind. Ultimately, two million people died, one-quarter of the entire population. One million immigrated to the United States.

How the Potato Twice Changed World History

The historian William H. McNeill (1999) believes that potatoes twice made a critical difference in world history: first, in South America, where the vegetable provided the principal energy source for the Inca and their Spanish successors. There would have been no great Incan civilization, McNeill contends, without chuno. Not only was it collected as taxes from the peasant-farmers, it was also disbursed from storehouses to pay labor gangs for building roads, waging war, and erecting great monuments. Once the Spaniards arrived and conquered the Inca, chuno is what fed thousands of conscript miners, forced by the conquistadors to work the silver mines in Bolivia. This tremendous influx of silver contributed to worldwide monetary inflation, and enabled Spain to build a powerful naval fleet.

The second way in which the potato changed world history was in northern Europe. The extraordinary strength of the industrial, political, and military changes between 1750 and 1950 could not have taken place without an enormously expanded food supply from potatoes, which served to feed a rapidly growing population, McNeill argues. Germany could not have become the leading industrial and military power of Europe after 1848, and Russia could not have assumed so threatening a stance on Germany's eastern border after 1891. Both events helped set the stage for two world wars.

The Potato Becomes Haute Cuisine

The French were no more enamored of the potato at first than any other Europeans. Legrand d'Aussy, in his 1782 Histoire de la vie privée des Français (History of the private life of the French) wrote that the pasty, indigestible tuber should be eliminated from aristocratic households and left to the poor. Also in 1783, a Parisian gourmet expressed outrage that the potato had achieved a certain cachet in the capital. The nineteenth-century French gastronome and author of the esteemed La physiologie du goût (The physiology of taste, first published in 1825), Brillat-Savarin agreed that the tasteless potato was good only as a defense against famine.

As in other European countries, the peasantry took to potatoes much more quickly because it could be used in their diet like turnips. Around 1620 (during the reign of Louis XII), the Abbey of Remiremont accepted payments in potatoes. As early as 1673, the tubers were being cultivated on a large scale in Lorraine. By the first half of the eighteenth century, the potato was well established in France, even if it was only among the peasants. By the middle of the century, potatoes began to be grown in the Pyrenees and Dauphiné, both very mountainous areas. By 1780, potatoes were the chief food of the Pyrenean highlands. By 1840, the potato was well established in French cuisine, making its way in through the soup pot, where it added bulk and absorbed flavors.

The person most credited with winning acceptance for the potato in France was eighteenth-century army pharmacist Antoine Parmentier. As a prisoner in Germany during the Seven Years War (1756–1763), he was forced to eat potatoes almost exclusively and became convinced of their virtues. He set about analyzing their chemistry. Then he won a competition sponsored by the Academy of Besançon to identify foods that could stem mass hunger after the famine of 1770. To counter the fear of anything in the nightshade family (more intense in France than in England), in 1771 the Faculté de Paris published a paper stating emphatically that the potato was innocuous. After yet another famine, Parmentier himself wrote in 1789 that, although the tuber was a nightshade, it was not soporific. To further convince the populace of the potato's appeal, he had the tubers planted on the worst possible land on the outskirts of Paris. During the day, the field was guarded by soldiers who left at night. The peasants, intrigued by such an important crop, went into the field and stole potatoes to plant in their own gardens, which is exactly what Parmentier wanted to happen.

Realizing that acceptance of the potato needed to begin at the top, Parmentier is said to have convinced Louis XVI to encourage planting and eating the tuber by throwing all-potato banquets. Even Marie Antoinette was said to wear potato flowers in her hair at court. Although these colorful stories may be apocryphal, between 1770 and 1840 potatoes became widely cultivated in northern parts of the country. When famine struck in 1788 because the grain crop failed, potatoes were available.

In 1793, during the "Reign of Terror," the French people celebrated potatoes as their republican salvation. Even the royal Tuileries gardens were symbolically converted into a potato field. Realizing the political strength potatoes could provide, the Republic published ten thousand copies of a pamphlet on cultivation. A year later, a cookbook, La cuisinière républicaine, presented twenty recipes. The annual potato crop burgeoned from 59,640,000 bushels in 1815 to 332,280,000 by 1840. By 1843, France produced almost half a million bushels of potatoes, possibly the largest crop on the continent and in all of Europe.

Potatoes gradually acquired a place in haute cuisine. Collinet, the chef for King Louis Phillippe (reigned 1830–1848), accidentally created the famous pommes soufflées (puffed potatoes) when he plunged fried potatoes into extremely hot oil to reheat them when the king was late for dinner. Much to the chef's surprise, the potatoes puffed. Pommes frites (what we call french fries) appeared on city streets in the north of France around 1870. The Larousse Gastronomique, the encyclopedia of French cuisine, first published in 1938, contains dozens of classic French recipes for potatoes.

The Potato in America

While potatoes migrated from South America to Europe, they failed to travel out of South America to North America or even to Central America and Mexico. In fact, Mexico did not have potatoes before the eighteenth century. It took about two hundred years—after the tubers made their way to Europe—before they were introduced into North America. This may have happened as early as 1613 in Bermuda, and on the mainland in 1621. The first North American colonial potato growing dates from 1719, when Irish immigrants, escaping starvation from the famine, introduced the potato to New Hampshire.

Americans did not subject the potato to class distinctions, so its popularity grew rapidly. In 1806 the American Gardener's Calendar included only one variety of potato; by 1848, almost one hundred kinds were exhibited at the Massachusetts Horticultural Society fair. By 1860, American output of potatoes was calculated at 100 million bushels, 90 percent produced by the northern states, with New York the single largest producer, followed by Pennsylvania, Ohio, and Maine.

A major step forward in potato cultivation was made in 1872 when the botanist Luther Burbank discovered that the Early Rose potato produced a seed ball, and was able to breed plants with larger tubers whose yield sometimes doubled or tripled that of its parent. The resulting progeny became known as the Burbank potato, which a few decades later mutated into the Idaho (or Russet).

For nineteenth-century farming life, the potato was a real boon for the same reason it became popular elsewhere as a cheap, nutritious, convenient way to feed farmhands and families. The potato, however, was not kept down on the farm; in 1876, some American hotels offered five different potato dishes for breakfast. During the Alaskan Klondike gold rush (1897–1898), potatoes were at times almost worth their weight in gold, so valued for their vitamin C that desperate miners traded gold for them.

In October 1995, the potato became the first vegetable to be grown in space. NASA and the University of Wisconsin created the technology with the goal of feeding astronauts on long space voyages, and, eventually, feeding future space colonies.

Cultivating Potatoes

Potatoes are most often grown in cooler climates in moist, acidic soil (pH slightly less than 6). They must be able to gather sufficient water from the soil to form the starchy tubers that range anywhere from three to twenty in number on any one plant, depending on variety, weather, and conditions. In the United States, most potatoes are produced in Idaho, followed by Washington, Oregon, Maine, North Dakota, California, Minnesota, and Wisconsin. Six varieties account for 80 percent of the crop yield.

Although potatoes are perennials, they are treated as annuals since the edible part of the plant that contains the buds is dug up each year. Farmers grow particular tubers as seed potatoes (not intended to be eaten) for propagating new crops. These potatoes are cut into what are called "sets," small pieces, with at least one eye or leaf bud on the surface, with some of the flesh of the potato still attached to supply the initial energy for the plant. The sets are planted with the eyes facing upward; new plants sprout from the eyes.

The potato plant produces leaves and flowers that can be white, purple, lilac, or violet, depending on variety. If fertilization of the flower is successful, a small green fruit ball is produced containing fifty to two hundred seeds, known as true seed. These can be planted for the next year's crop rather than using seed potatoes. The leaves supply abundant food for the plant's growth, and the generated surplus moves down into the underground tuber for storage. Potatoes can be left in the ground for four to six weeks. They are harvested when all of the leaves and tops of the plants have withered. A potato that is harvested young, usually in the spring or early summer, and sent directly to market instead of being stored, is known as a new potato.

Before potatoes can be sold or shipped, they must be sorted for size and quality. This process is called "grading" and special implements are used. These can be as simple as a wooden slat with a bag on the end for acceptable potatoes, or a more complicated conveyor-belt system that moves potatoes toward the bag at the end as inspection is performed.

Potatoes produce the steroidal alkaloid solanine, which seems to protect the tubers and foliage from some predators and insects. Still, potatoes are vulnerable to such pests as the Colorado potato beetle, red slugs, and blister beetles, and are still attacked by blight. Since 1990, fungicide-resistant strains of blight have struck fields in various parts of North America.

Culinary Preparation of Potatoes

Potatoes figure prominently in many of the world's cuisines, particularly in the Americas, in Europe, and in countries colonized by Europeans: pommes de terre soufflées and pommes Anna in France; hot potato salad, noodles, dumplings, pancakes, and bread in Germany; as a base for soups and puddings and stuffing for pierogi in Russia and Poland; colcannon—a mixture of potatoes and kale, turnips, or cabbage—and cobbledy, potatoes mashed with milk, butter, salt, pepper, and onions in Ireland; as an ingredient in the Spanish omelette; in the latkes and knishes of Jewish food; for the sauce skordalia in Greece; in raclette and roesti in Switzerland; for gnocchi in Italy; stuffed potatoes and savory causa, mashed potato cake, in Peru; for lefse, thin potato pancakes in Norway; in fish and chips, mashed potatoes, shepherd's pie, and Cornish pasties in England; potato casserole in Finland (Imellettyperunasoselaatikka), a dish that undergoes a malting process wherein the starch of the potatoes breaks down to form a simple sugar; french fries, potato chips, and stuffed potatoes in the United States.

Potatoes can be used in every course of a meal, even dessert. They can be fried, boiled, steamed, braised, roasted, sliced, diced, chopped, and mashed. A large part of their versatility is their neutral taste, which provides a palatable backdrop for almost all other foods. For dessert, potatoes can be used with or without chocolate in cakes, pies, doughnuts, cookies, and candies. Since potatoes contain no gluten, adding some mashed potato to dough makes it particularly tender.

For cooking, potatoes are classified according to starch content—high, medium, or low—which affects the way they cook and the resulting texture. High-starch potatoes (Russets and Idahos), also known as mealy or floury, are the first choice for baking and frying. The use of the microwave to bake potatoes has considerably shortened what used to be a lengthy process. The large starch granules swell up and separate, making for a light and fluffy texture. Medium-starch potatoes (white all-purpose and yellow-fleshed, including Yukon Golds) have a creamy texture and become soft but do not disintegrate when cooked. Low-starch potatoes (round red and white boiling potatoes), also known as waxy potatoes, are the first choice for boiling, steaming, and roasting. They contain more of the starch known as amylopectin, with granules that stay close and dense even after cooking.

Once purchased, potatoes need to be stored in a dark, but dry, place to ensure they do not turn green or sprout. Generally, store-bought potatoes have been sprayed with a chemical that inhibits sprouting. Even a little warmth and light, however, may provoke the eyes to use the stored energy in the tuber for growing.

The substance that sometimes appears as a greenish cast under the skin and in the eyes of the potato is the alkaloid solanine, the natural pesticide that protects the plant as it grows. All potatoes contain trace amounts (1–5 mg). Its appearance on store-bought potatoes means they have been "light-struck," exposed either to natural or artificial light. According to Federal Food and Drug Administration guidelines, levels higher than 20 mg per 100 g of potato make the vegetable unfit to eat. Consequences of solanine toxicity range from minor upset stomach to serious illness. To avoid this, proper storage and cutting away all traces of green on the potato are necessary.

Relation to Human Biology

Potatoes contain anthoxanthins, pigments that produce the white color and act as antioxidants, believed to have some cancer-preventing activity. Specifically, unfried potatoes are among those vegetables containing the highest levels of the antioxidant glutathione. When compared to bell peppers, carrots, and onions, potatoes have the greatest overall antioxidant activity. Only broccoli is higher.

French fries and potato chips, however, may pose a cancer risk. Separate studies by the national food agencies of Sweden, Britain, and Norway have reported high levels of acrylamide, a carcinogen in rats and probably one in humans, in potato products fried at high temperatures. Until there is more evidence, the World Health Organization and the United Nations Food and Agriculture Organization have not been able to determine whether consumers should cut back on their intake of fried potato foods, particularly chips.

Eating unfried potatoes contributes to the minimum goal of five servings of fruits and vegetables a day, recommended by the U.S. Department of Agriculture's (USDA) Food Guide Pyramid and designed to provide optimum good health.

Symbolism of the Potato

In the United States, the potato has found its way into pop culture. A "couch potato" is a sedentary person; "hot potato" indicates a volatile issue or topic; "small potatoes" refers to something that is not a big deal; a "meat and potatoes" person is someone who eats only the basics. Calling someone a "potato head" is not a compliment because it means someone who is dense. A familiar children's rhyme begins, "One potato, two potato, three potato, four." The children's toy Mr. Potato Head®, introduced by Hasbro in 1952, and Mrs. Potato Head®, in 1953, came packaged with plastic eyes, ears, nose, mouth, feet, and hats to insert into a real potato supplied by the buyer. In 1960, the kit also came with a potato-shaped plastic body. The image has been licensed worldwide for a variety of popular uses including T-shirts, clocks, and Halloween masks.

Since its earliest appearance in Europe, the potato has been associated with the poor and the working class. When the Spanish first stumbled on the potato in Peru, they looked down on it as slave food. The exotic sweet potato was brought from Haiti to Europe as soon as it was discovered by Columbus, but it took the conquistadors more than thirty years to bring potatoes to Spain, and then they came as food for sailors. For a long time, the potato continued to be regarded as food fit only for the poor and as animal fodder, useful only in the event of starvation.

In America, where the potato did not have a class barrier to break down, its association with fat and grease—deep frying—has reinstated some of its lowly image. A headline a few years ago in the New York Times read, "The Rich Get Richer and the Poor Get French Fries." The irony is that, by cooking it in fat, the 99.9 percent fat-free fresh potato is transformed into a high-fat snack.

Commercialization of Potatoes

An early reference to commercial potato growing dates from 1762, when the tubers became a field crop in Salem, Massachusetts. In the following year, Connecticut valley potatoes were listed as an export, but the buyers were West Indian planters, looking for cheap food for slaves. By 1848, about half a dozen varieties of potatoes were being grown commercially, the same number grown in the twenty-first century.

Processing of potatoes began not long after they began to be grown commercially. In the 1870s and 1880s in both France and America, manufacturers began making equipment for deep frying, which made commercial production of fried potatoes and french fries a reality. Mass production depended on the availability of cheap oils that appeared right after the Civil War. In 2002 in the United States, nearly half of the potato harvest ends up being fried.

Unfortunately, processing takes much of the taste out of potatoes, and undermines their quality as growers shift to varieties demanded by processors rather than those that are best fresh. Potato products are made from potatoes that have been reduced to powder in one of two ways. The first is simple cooking, drying, and grinding, which preserves the solids in more or less their original proportions. This is how potato flour is made. Derivatives of potato flour include instant mashed potatoes, frozen potato products, and potato chips.

The second method involves extracting starch from potatoes by a washing process. This is how potato starch is made, which is commercially packaged to be used as a thickener and to make cakes, biscuits, puddings, pies, and sauces for Jewish Passover to fulfill the religious requirement that no flour be used in their preparation.

The first large-scale production of dehydrated potatoes began in 1942, when the potato processor John Richard "Jack" Simplot, already the nation's largest shipper of fresh potatoes, won a government contract to supply dried potatoes to the armed forces during World War II. By 1945, he had supplied about 33 million pounds of dehydrated potatoes to the military. French's Instant Potato was introduced by the R. T. French Company in 1946. Frozen potatoes came later, at first simply precut for french fries. By 1962, frozen, dehydrated, and canned potatoes accounted for 25 percent of U.S. potato consumption. By 1966, per capita consumption had risen to 44.2 pounds a year, up from 6.3 in 1950.

The Potato Chip

In 1853, that quintessentially American product, the potato chip, was invented serendipitously. Annoyed when Commodore Cornelius Vanderbilt (the railroad magnate) sent back his fried potatoes because they were too thick, George Crum, the chef at the Half Moon Hotel in Saratoga Springs, New York, thought he would teach him a lesson. Crum sliced some potatoes paper thin, deep-fried, and salted them. Vanderbilt loved them.

Potato chips began to be commercially manufactured as early as 1915, when Van de Kamp's Saratoga Chips, a storefront operation, opened in Los Angeles. In 1921, Wise Potato Chips were introduced in Berwick, Pennsylvania, by Earl Wise, a local grocer. Finding himself overstocked with old potatoes, Wise peeled and sliced them, and then followed his mother's recipe for making chips and put them in brown paper bags. In the early 1930s, he switched to the more practical cellophane bags. By 1942, Wise had opened a 40,000-square-foot plant.

In 1969, General Mills introduced Chipos, and Procter & Gamble brought out Pringles, both made from cooked, mashed, dehydrated potatoes that were then reconstituted into dough and cut to uniform size (rather than made from sliced potatoes fried in oil). These new "chips" were packaged in break-proof, oxygen-free containers to prolong their shelf life. The Potato Chip Institute sued to prevent the products from being sold as chips, but lost. The Food and Drug Administration ruled that chip products not made from fresh potatoes must be labeled "potato chips made from dried potatoes." By the time the ruling was to have taken effect in 1977, fabricated chips had already lost their appeal.

In 2001 in the United States, nearly $2.7 billion worth of bags were sold, according to Information Resources, a market research firm. A survey by the Department of Agriculture found that the average American snacker eats 33 pounds of chips per year.

Issues in the Twenty-first Century

To combat the threat of pest damage and fungicide-resistant blight, scientists have experimented with breeding blight-resistant germ plasm and biotechnology that involves placing a gene into an already existing variety to improve its resistance to disease, insects, or stress. For example, resistance to the Colorado potato beetle has been placed into the Russet Burbank potato by inserting genetic material from the bacterium Bacillus thuringiensis into the plant. This causes a protein to be manufactured that disrupts the digestive system of the beetle when it feeds on the leaves. The Shepody variety of potato has been improved to make it more resistant to viruses, one of the major causes of declassification of seed in the potato industry. The gene prevents replication of a virus after it has been introduced by aphids. Monsanto's NewLeaf potato is the first genetically engineered potato, designed to protect it from the Colorado potato beetle. It was approved in the United States in 1995, and subsequently in Canada, Mexico, and Japan. The NewLeaf Plus, the next generation from Monsanto, resists both the beetle and the potato leaf roll virus.

Biotechnology is not without controversy. Some critics point out that it gives corporations like Monsanto a profitable monopoly on the seed since it must be replanted each year. Others are concerned that the long-term effects are not known. A major concern is that there is no requirement to label genetically engineered products. There are even larger questions about whether biotechnology offers a reasonable way to feed the world's hungry; most experts maintain that the amount of food is sufficient and it is distribution that is the crucial issue.

Genetic Diversity

Many observers believe that the solutions to the agricultural issues lie in plant breeding and preserving the genetic diversity of potatoes. By planting a larger number of varieties, farmers guard against damage of blight or insects that might destroy one variety but not another. There is some reason to believe that, if Ireland had planted its fields with a diverse crop, the toll from the famine would not have happened.

Today, only half a dozen varieties constitute the vast majority of the nation's crop. In the final decade of the twentieth century, there was a resurgence of interest in potato varietals and their preservation and development. Of particular interest are heirloom potatoes, those developed over centuries for which the seeds have been handed down from one generation to the next.

To protect the genetic diversity of the potato, and to make it available for systematic manipulation, the International Potato Center in Lima, Peru, under the auspices of the Consultative Group on International Agricultural Research, has collected about 5,000 samples of native cultivars from nine countries in Latin America, representing about 3,500 genotypes. Every aspect of the potato and its place in the environment and human society is studied. Recent projects have included an effort to develop tropical varieties for Africa, Hong Kong, and the Philippines.

See also Biotechnology; Central Europe; Columbian Exchange; Distribution of Food; Fast Food; French Fries; Genetic Engineering; Germany, Austria, Switzerland; Hamburger; Ireland; Scurvy; Snacks; Sweet Potato; Vegetables.

Linda Murray Berzok