The potato is a tuber produced by a vegetable plant that bears the same name. “Potatoe” in English, “potato” in Canadian, it’s grown on every continent of the planet, it’s the most consumed vegetable in the world.
The potatoes are on the markets all year round thanks to the many varieties which succeed from one season to the next but also to the storage with chemical inhibitors and germicides or after irradiation, processes neutralizing the germination. New potatoes or primers are harvested before their full maturity. This appellation is allowed from the beginning of the harvest (April, May) until 31 July and off-season for import potatoes.
History of the potato
The term “potato” originates from the Spanish, Arawak, an Indian language of Haiti. It first designated the sweet potato then, under the influence of the English potato, the potato. As for the name “potato”, it appeared in the middle of the seventeenth century and first designated the Jerusalem before referring to the nightshade.
The potato originates from the Peruvian and Colombian Andes, as well as from Chile. Its centre of genetic diversity extends from the tip of Argentina to the southwest of the United States. In this vast territory where all the climates are found, there are more than 200 wild species of Solanum, the Lake Titicaca region (Peru and Bolivia) being the richest reservoir. It’s probably in this region that it was domesticated 7 000 to 10 000 years ago, from 2 wild species.
The potato crossed the Atlantic to Europe around 1570, by 2 streams: one Spanish and the other English. For a long time, farmers were satisfied to cultivate the plant as a curiosity or for its beauty, refusing to consume its tuber. The authorities eventually recognized its very high productivity and nutritional properties. But they took time to convince people to adopt it as a food. It is the wars and famines that will encourage people to consume potatoes. The potato can be kept in the soil, which puts it relatively safe from looting and fires caused by marauding armies. On the other hand, in bad years it’s much more productive than cereals.
In fact, some researchers do not hesitate to attribute the demographic increase that led to the industrial revolution in its wake. First because, thanks to this vegetable, frequent famines had disappeared. Then, because its large-scale production had resulted in some over production. This had made it possible to feed an increased number of people, both in the countryside and in the cities, in addition to constituting excellent food for the livestock and poultry.
Today the potato is, after wheat, rice and maize, the most important crop on the planet. The establishment of the international potato Centre in Peru in the 1970 years helped to develop many varieties. Culture techniques adapted to various climates have been developed, particularly for the humid tropics of Africa and Asia. As a result, potatoes are now being grown in areas where it had not been possible to do so before. It represents, for the farmers of these countries, a significant income. Which still helps to improve their quality of life. Additionally, a very digestible food, rich in nutrients, is added to their menu.
On the other hand, in developed countries, the consumption of fresh potatoes continues to decrease for the benefit of food products made with potatoes. Chips and fries are much less nutritious and much fatter.
Potato health profile
In the oven, in puree or in salad, the potato is ready in many ways and it’s very digestible. It contains a lot of dietary fiber and a profusion of vitamins and minerals. Try the potatoes with blue or violet flesh, they are rich in antioxidants.
A few words on the potato
The potato contains much more starch (a carbohydrate) than most vegetables. This is why some nutritionists believe that it should be regarded as a starch, in the same category as bread and pasta. But the Canadian food guide ranks it among the fruits and vegetables. It also contains an impressive amount of vitamins and minerals, as well as other compounds with beneficial health effects. So it has its place in a varied and balanced diet. The potato is the most consumed vegetable in North America, but unfortunately too often in the form of fries.
The benefits of potato
Cardiovascular diseases. One study showed that, among healthy men, daily consumption of yellow-or purplish-fleshed potatoes reduced inflammation and oxidative stress. These two factors would contribute to the prevention of cardiovascular disease.
Blood lipids. Studies indicate that resistant starch (a complex sugar) from potato flesh, added to the animal diet, would result in decreased cholesterol and blood triglycerides. Raw potato resistant starch, administered to rats, would also reduce the “bad” cholesterol (LDL) In addition to increasing intestinal fermentation and improve the absorption of some minerals. Possible clinical studies will assess whether similar results can be obtained among humans.
Several prospective and epidemiological studies have shown that high consumption of fruits and vegetables reduces the risk of cardiovascular disease, certain cancers and other chronic diseases. The presence of antioxidants in vegetables and fruits could play a role in these effects.
Cooking would not greatly affect the antioxidant capacity of the potato. According to different studies, once cooked, it would retain up to half its contents in phenolic compounds (including phenolic acids and flavonoids) and even up to 97% in some cases.
What does the potato contain?
The potato contains phenolic acids (chlorogenic acid), flavonoids (catechins), as well as vitamin C5. These antioxidant compounds protect the body cells from damage caused by free radicals.
The content of phenolic compounds of the potato differs considerably according to the variety, the conditions of culture and climatic, as well as the methods of analysis used. For example, varieties of yellow-or purplish-fleshed potatoes would have more phenolic acids than white-fleshed potatoes. The potato peel would also be richer in phenolic acids than its flesh. Blue or purplish-fleshed varieties have more flavonoids than “traditional” potatoes and their consumption would increase the organism’s antioxidant capacity.
The more they are colorful, the more beneficial for health
There are now on the market potatoes whose flesh is of varying colour (blue or purple, yellow, red). These varieties are particularly interesting because of their exceptionally high antioxidant content. These can be flavonoids (anthocyanins) which gives them their particular color, lutein or zeanxanthine. The white potato would have a lower anti-cancer activity than many other vegetables, while the antioxidant capacity of red and purplish potatoes would be comparable to that of Brussels sprouts, spinach or kale. Some varieties under study could contain almost as many antioxidants as blueberries, recognized as the best source of antioxidants.
The potato contains starch, a complex carbohydrate. A fraction of this starch is resistant starch. Like dietary fibers, resistant starch is not digested by human intestinal enzymes and is not absorbed by the small intestine. The raw potato contains more resistant starch than the one that has undergone a transformation and this quantity varies according to the different processes used. Boiled potatoes would contain about 2% resistant starch, 5% fried potatoes and 6% potato salad. These values are comparable to those of different cereal products (breakfast cereals, rice, pasta, etc.) and slightly lower than those of legumes. In addition, the amount of resistant starch contained in potatoes would increase when they are warmed and cooled.
Some researchers believe that resistant starch could help reduce the risk of colon cancer. However, contradictory results obtained among animals do not permit the conclusion of a protective effect of the resistant starch against the formation of colon tumors. The resistant starch would also have beneficial effects on the blood lipids.
The potato is an interesting source of fiber. For example, an baked potato provides approximately 10% of the recommended daily fibre inbring for adults aged 19 years to 50 years. Food fibers, found only in plants, group together a set of substances that are not digested by the body. In addition to preventing constipation and reducing the risk of colon cancer, a diet rich in fiber can contribute to the prevention of cardiovascular disease, as well as to the control of type 2 diabetes and appetite.
There are many varieties of lectins, proteins found in plants. According to several in vitro studies, the potato-specific lectin, called STL (Solanum Tuberosum Lectin), would have the ability to inhibit the growth of cancerous cells. However, other studies are needed to determine whether it can help prevent cancer among humans.
Alkaloids (green color on potato)
The potatoes contain toxic compounds named alkaloids (Solanine and Chaconine), which provide protection against different pathogens found in the wild. Among humans, the consumption of alkaloids can be related to different symptoms (tingling sensation in the mouth, gastrointestinal discomfort, sweating, bronchospasm, etc.). When consumed in large quantities, the alkaloids can lead to serious intoxications which can affect the central nervous system.
When their alkaloid content is high, potatoes may have green tints or green patches. The cooking does not destroy the alkaloids and their concentration increases when the potatoes are stored at high temperature or in the light. It is therefore important to keep them away from moisture and light, to remove the green patches or to discard the complete potatoes if there are too many of these stains.
Cases of potato allergies (raw or cooked) have been reported, mainly among children. These allergies can cause various symptoms, more or less severe. The protein is responsible for these allergies. People who are allergic to latex can also be hypersensitive to potatoes (as well as other foods such as kiwi, banana and avocado) and vice versa. The reactions are diverse, from urticaria to anaphylactic reactions. Given the potential severity of the reactions, very special attention must be paid at the time of consumption of these foods among people already sensitized to latex allergens. It’s recommended to consult an allergist to determine the cause of the reactions to certain foods as well as the precautions to be taken. According to a study carried out among young children, allergy to baked potatoes would increase the risk of suffering from pollen allergy later in childhood.
Oral allergy syndrome
The potato is an incriminating food in the oral allergy syndrome. This syndrome is an allergic reaction to certain proteins of a range of fruits, vegetables and nuts. It affects some people with allergies to environmental pollen and is almost always preceded by hay fever. Thus, when some people allergic to ragweed consume raw potatoes (cooking usually degrades allergen proteins), an immunological reaction may occur. These people feel itching and burning sensations to the mouth, lips and throat. Symptoms may appear, then disappear, usually a few minutes after the food is consumed or a contact with it. In the absence of other symptoms, this reaction is not serious and the consumption of potatoes does not have to be avoided systematically. However, it is recommended to consult an allergist to determine the cause of the reactions to plant foods. The latter will be able to assess whether special precautions should be taken.
Selection and conservation
Preferably buy yellow, red or blue-fleshed varieties that are richer in nutrients than the white potato. It may be necessary to go to the market to find them, because they are still scarce in grocery stores.
Look for varieties with elongated small tubers, such as Ratte, German Fingerling, banana, comma potato, etc. Their taste is more delicate, and they can be served whole without overloading the plate.
The ideal for potato culture is a rich land with a relatively low pH.
Many diseases affect this plant, the most devastating in tempered climates being downy mildew and scabies. The first, which was the cause of the Great Famine in Ireland from 1845 to 1849, is in resurgence. It’s a threat even in family gardens, which are generally better protected from disease.
To prevent downy mildew, it’s recommended to plant only healthy certified tubers from resistant varieties, to irrigate the soil by avoiding watering the foliage and to practice a rotation of 4 or 5 years (this also applies to tomatoes that are very vulnerable to disease). It’s also useful to properly butter the plants and to add a mulch to isolate the foliage of the tubers as much as possible. It’s recommended to make every week a foliar application of Bordeaux porridge, a fungicide accepted in organic agriculture. The severely affected seedlings should also be destroyed as well as the leaves of the plants having less effect by burying them deep as far away as possible from the garden.
The same protective measures apply to scabies. On the other hand, Bordeaux porridge is not treated and the soil is kept constantly moist during the first few weeks of tuber formation. Avoid any fertilizer or amendment that has the effect of alkaline soil: fresh manure, especially poultry manure, lime or ash. If necessary, lower the pH by incorporating sulphur on the soil the year before the crop.
Some varieties of potatoes are susceptible to cabbage rot. So it is better to keep them away from it in the garden.
To control the beetle, the main insect attacking the potato, it’s possible to cover the plants with a thin net fabric, which prevents the adult from landing and laying his eggs on the plants. In commercial culture, this technique is too costly, but for the family garden it is affordable and it’s the most environmentally friendly. Neem oil and rotenone (two plant insecticides) will be used only in case of absolute necessity, as they are not selective and destroy useful insects.
Ecology and environment
During the 250 years following the introduction of the potato in Europe, the varieties cultivated there came from an extremely small genetic variety. Some had predicted this potentially explosive situation, long before the Irish Famine. The lower the genetic diversity of the potato is, the higher the risk of attacks by diseases or insects. So it happened what had to happen: when downy mildew, a fungal disease, hit Europe after the United States, it did not encounter any resistance in this genetically uniform plant population.
Preserving biodiversity is therefore essential if we are to be able to combat diseases and insects, which are increasingly virulent, attacking the potato. Until recently, it was not uncommon to see the Amerindians cultivate on the same mound 5 different varieties. In addition, cultivated varieties were readily allowed to mingle with wild varieties or species growing near the fields. This allowed the creation of new cultivars, some of which, hopefully, could have a high natural resistance against one or the other of the potato’s enemies. Alas, this diversity is likely to continue to erode as some high-yielding cultivars are introduced today, which gradually replace the many less productive local varieties.