As a vegetable crop (as opposed to a grain crop), the potato is the world’s most important foodstuff, so there are many interesting facts about potatoes. The starchy tubers of the potato plant are exceptionally nutritious and so rich in carbohydrates that potato fields can yield 2- 4 times as many calories per acre than can grains. Potatoes can be grown, with little effort, in a variety of soils, and under tremendously diverse growing conditions. As we shall see, it is no wonder that potatoes have come to represent such a large proportion of the world’s food crops.
The first potatoes appear to have been harvested as long as 10,000 years ago on a chain of islands off the coast of Peru. According to the DNA record, the plant we know today (technically it is S. tuberosum ssp. tuberosum) was domesticated somewhere between 3000 and 2000 BC, again, in Peru. Since that time as many as 5,000 varieties of potatoes have been grown for food, the bulk of which occur only in the Andes Mountains at high elevation.
The potato was introduced to Europe, in 1534 by Francisco Pizarro upon his return from Peru. It then traveled from port to port, as it was well suited for storage on boats. Spanish fishermen brought the potato to the western shores of Ireland, for instance, as this was a routine port of call where cod could be dried. In 1580, Francis Drake returned to England after circumnavigating the globe, and presented the potato to the court of Elizabeth I as part of his booty. By 1601 potatoes were being grown as far south as Italy, where they were produced food for both people and livestock. By the early 17th century, potatoes had also made their way as far east as the Philippines and China. One hundred years later, potatoes were being grown as a major crop in northern India.
In times of famine, the potato repeatedly proved that it could sustain a population. Potatoes, being grown underground, were an inconspicuous crop, and were not plundered as frequently by invading armies, as were grains. It was just a very sensible crop to fall back on in hard times, and virtually anyone with access to a plot of land could grow some. Friedrich Engels declared that the potato played a “revolutionary role” in history.
Of course, in 1845, the dependence on potatoes by peasant populations proved disastrous in Ireland. Although nearly all poor Irish families relied on potatoes for sustenance, very few varieties were grown and this left the crop susceptible to a kind of fungus known as late blight. This fungus (Phytophthora infestans) swept through Western Ireland and caused mass famine, killing a million or more people, and led to mass emigration to Britain and North America.
It is estimated that the average person eats around 33kg (73 lbs) of potatoes each year. In some Eastern European countries, per capita consumption is much higher — the average Belorussian eats 338kg of potatoes in a year, or about 2 lbs per day. Today, China and India produce about a third of the world’s potatoes.
Potato plants are perennial members of the nightshade family, Solanaceae, and close cousins to tomatoes, peppers, eggplants, and tobacco. This is evidenced most obviously by the structure of the flowers on each plant — though potatoes themselves may have pink, white, blue, or even red flowers. All Solanum flowers have yellow stamens.
If potato flowers are pollinated, they sometimes form fruits.
Many potato varieties produce fruits after flowering. These are small and green, and look a bit like cherry tomatoes, but they are naturally occurring and do not represent cross-pollination (as is sometimes thought) with tomato plants. The fruits, which contain high levels of the toxic alkaloid solanine, should not be eaten. They contain true seeds that can be grown out into new potato plants, but this is a slower process than simple vegetative reproduction by using the tubers themselves. Such tubers are called seed potatoes.
Potato varieties are surprisingly abundant. The Canadian Food Inspection Agency recognizes 173 different registered varieties in Canada alone, but there are as many as 4,000 different types grown around the world. They are broadly divided into baking vs. boiling types, based on starch content, but some references break them down into similarity by colour as well: Whites, yellows, russets, reds, and purples. Baking potatoes (also called floury or mealy potatoes) contain more of the starches amylose and amylopectin than boiling, or “waxy” potatoes.
Potatoes are incredibly versatile in the kitchen, and can be boiled, roasted, baked, scalloped, hashed, mashed, or fried. It is recommended to use potatoes with the skin intact, regardless of how you like to prepare them, as the layer just beneath the skin contains the highest proportion of protein, fibre, vitamins, and minerals. Much of this is lost when the vegetables are peeled. Unpeeled, a medium-sized potato offers 27mg of vitamin C, 620mg of potassium, 0.2mg of vitamin B6, as well as trace amounts of folate, niacin, thiamin, riboflavin, magnesium, phosphorus, iron, and zinc. This same quantity of unpeeled potato contains as much dietary fibre as a similar amount of whole-grain bread, plus 2g of protein and 26g of carbohydrates.
Potato festivals are popular across North America, as towns celebrate their financially important harvests. In Alliston, a small town northwest of Toronto, they have been enjoying the Alliston Potato Festival for close to 40 years running. By hosting a parade, a midway, live music, a battle of the bands, and masses of potato-themed food, the town raises money for improvements to local sports and youth centres, and civic projects. Head to Alliston for the second weekend in August for your annual dose of potato fun.