Tubers: Characteristics, Types, Properties and Examples

The tubers They are stalks of food storage of some plant species, grow below ground and serve for asexual propagation. The plant uses them for survival during winter or drought, and as a reserve of energy and nutrients for regrowth, during the next growing season.

There are edible tubers and other employees in gardening. Among the latter are the Cyclamen, Sinningia and some begonias. Among the common food species of stem tubers are potatoes ( Solanum tuberosum ) and the yam or yam ( Dioscorea spp ).

They also highlight the ocumo ( Xanthosoma sagittifolium ), the taro ( Colocasia esculenta L.), the olluco, the smooth potato, the ruba, the ulluco or melloco ( Ullucus tuberosus) and the rutabaga ( Brassica oleracea ). Under this definition are some species that arise from a thickening of the roots (root or root tubers).

Among the latter are cassava, cassava or cassava ( Manihot esculenta ); the sweet potato, sweet potato, sweet potato or sweet potato ( Ipomea batata ); celery ( Arracacia xanthorrhiza ); and the red beet ( Beta vulgaris ).

Main characteristics of the tubers

Humans and animals take advantage of the accumulation of nutrients in the short thickenings of roots and stems that grow under the ground.

The tubers are constituted basically of starch and water. All have a low content of nitrogen compounds and the amount of fat is practically nil.

For example, potatoes and cassava are important sources of vitamin C when ingested in large quantities, although a significant part is lost during cooking.

The celery and the sweet potato or sweet potato are provitamin A, being the varieties more colored and the richest in this nutrient.

Types

The tubers can be classified into two types: stem and root.

An example of tubers of stems are potatoes. Its upper sides produce buds and leaves, while the lower sides produce roots. They are often located on the surface of the soil and grow on the sides of the original plant.

An example of a root tuber is sweet potato. It has a modified lateral root that functions as a storage organ, which can grow in the middle of a root, at the end or at the complete root.

Properties / health benefits

Essential nutrients

Tubers are a great source of minerals, soluble fiber and essential vitamins.

For example, sweet potatoes are a rich source of vitamin C and beta-carotene, which act as antioxidants, protecting the body from free radicals.

Minerals

The tubers are rich in minerals such as fiber, manganese, potassium and copper, which act to keep the excretory and digestive system healthy.

Fiber promotes better digestion, minimizes fat absorption and reduces the risk of cardiovascular diseases.

Reduces tissue damage

The nutrients of the tubers act by repairing tissue damage. For example, the Vitamin A improves vision and reduces visual problems. On the other hand, vitamin C repairs cellular damage.

Apart from these general nutritional properties, the following will discuss the particular characteristics of some tubers.

Examples

Celery ( Arracacia xanthorrhiza)

The plant is native to the Andes region and grows at altitudes ranging from 200 to 3600 meters above sea level. It is often grown with other foods such as corn, beans and coffee.

You can not eat raw, but when it is cooked it develops a pleasant flavor and aroma. The boiled root is used similarly to potatoes. It is served as a garnish, crushed into puree, formed into meatballs and gnocchi, as an ingredient in cakes or soups.

They make fried chips, cookies and flour and celery starch. The latter is highly digestible.

100 grams of the edible portion of celery contain 94 Kcal, 73.2 g of water, 1 gram of protein, 0.1 g of fat, 24.3 grams of total carbohydrates, 2 grams of fiber, 1.1 grams of ash , 25 mg of calcium and 60 mg of phosphorus.

In addition, they have 0.9 mg of iron, 57 μg E.R. vitamin A, 342 μg total equivalents β-carotenes, 0.06 mg of thiamine, 0.04 mg of riboflavin, 3.5 mg of niacin and 18 mg of ascorbic acid.

Sweet potato ( Ipomea batata )

It is native to tropical America. Although the sweet potato, sweet potato or sweet potato is often called yam in North America, it is botanically very different from the genuine yam ( Dioscorea spp ), which originated in Africa and Asia.

It is consumed in multiple ways: boiled, mashed, fried or canned in syrup. In addition to simple starches, sweet potatoes have plenty of complex carbohydrates, dietary fiber and beta-carotene (a provitamin A carotenoid), is rich in potassium, low in sodium and with moderate contents of other micronutrients.

100 grams of the edible portion of sweet potato contain 108 Kcal, 68.7 g of water, 1.5 grams of protein, 0.4 g of fat, 28.5 grams of total carbohydrates, 3.8 grams of dietary fiber, 17 mg of calcium, 62 mg of phosphorus, 1.2 mg of iron and 25 mg of magnesium.

It is also composed of 0.90 mg of zinc, 0.16 mg of copper, 4 mg of sodium, 473 mg of potassium, 50 μg E.R. vitamin A, 300 μg total equivalents β-carotenes, 0.11 mg of thiamin, 0.05 mg of riboflavin, 0.7 mg of niacin and 23 mg of ascorbic acid.

Yam or yam ( Dioscorea spp )

They are native to India and Malaya, also grown in Oceania and America. They are eaten cooked, stewed or fried. Depending on the species and variety, the flavor is very variable, from sweet in some cases, to floury and with taste to chestnuts more often. Some African species are bitter, but not toxic.

The indigenous peoples in Guayana also make kalali , a traditional beer made from yams. 100 grams of edible portion provide 98 Kcal, 73.4 grams of water, 2.1 grams of protein, 0.2 grams of fat, 23.4 grams of total carbohydrates, 1.5 grams of dietary fiber, 18 mg of calcium , 49 mg of phosphorus and 0.9 mg of iron.

Within those 100 grams there are also 0.11 mg of zinc, 10 mg of copper, 393 mg of sodium, 0.12 mg of thiamin, 0.03 mg of riboflavin, 0.4 mg of niacin and 7 mg of ascorbic acid .

Some species of yams contain sterols, which serve the pharmaceutical industry as a raw material for the manufacture of contraceptive hormones.

Ocumo ( Xanthosoma sagittifolium )

It is native to Central America and its greatest development is in the tropics. It is very popular in Hawaii and other Pacific islands.

It has multiple names: bore, hoop, camacho, macabo, chonque, mangareto or mangarito, mafafa, mangará-mirim or mangarás, rascadera, elephant ear, yaro, taioba, tiquisque, yautía and malanga.

The plant is also ornamental. Both the tubers of the white and purple ocher are dark on the outside and contain acrid substances and alkaloids that must be destroyed by the heat prior to consumption.

The raw ocumo must not be ingested because of its high calcium oxalate content. This confers irritating properties and can cause transient muteness.

100 grams of the edible portion of the ocumo provide 103 Kcal, 71.9 grams of water, 1.7 grams of protein, 0.8 grams of fat, 24.4 grams of total carbohydrates, 2.1 grams of dietary fiber, 22 mg of calcium and 72 mg of phosphorus.

The formula is completed with 0.9 mg of iron, 3 μg E.R. vitamin A, 18 μg total equivalents β-carotenes, 0.13 mg thiamin, 0.02 mg riboflavin, 0.6 mg niacin and 6 mg ascorbic acid.

Olluco (Ullucus tuberosus )

It is one of the most important root crops in the Andean region of South America, from where it originated. It is consumed mainly the boiled tuber, in mashed or ground, as thickener of soups and stews.

The leaf is also edible and is similar to spinach. 100 grams of olluco provide 74.4 Kcal, 15.3 g of carbohydrates, 0.9 grams of dietary fiber, 0.1 grams of fat and 2.6 grams of protein.

Potato ( Solanum tuberosum L.)

It is a plant of American origin, specifically from the Andes: from Venezuela to Chile. There are some 5000 varieties of potato in the world and the same larger tubers serve as seed.

100 grams of the edible portion of the potato contain 81 Kcal, 77.5 g of water, 2 g of protein, 0.1 grams of fat, 19.5 grams of total carbohydrates, 1.6 grams of fiber, 8 mg of calcium, 45 mg of phosphorus and 0.8 mg of iron.

Also, in 100 grams of papatas there are 20 mg of magnesium, 0.35 mg of zinc, 0.09 mg of copper, 3 mg of sodium, 411 mg of potassium, 0.10 mg of thiamin, 0.06 mg of riboflavin , 1.2 mg of niacin, 0.31 mg of vitamin B6 and 20 mg of ascorbic acid.

Taro ( Colocasia esculenta L. )

It is believed that it comes from southern India and Southeast Asia, but it is widely spread in the Caribbean islands and in the American continent. In the Philippines it is known as gabi, abi or avi. It is consumed toasted, baked or boiled.

When this crude oil should not be ingested by the presence of calcium oxalate. Taro is an ingredient commonly used in Chinese and Taiwanese food. The tuber is smaller than the common owl and is white inside, although it shows outwardly dark concentric rings.

Unlike the yam, it does not turn yellow when cut. 100 g of taro provide 56.8 g of water, 1.2 g of protein, 0.2 g of fat, 40.9 g of total carbohydrates, 3.5 g of dietary fiber, 48 mg of calcium, 68 mg of phosphorus, 2.2 mg of iron, 0.18 mg of thiamin, 0.06 mg of riboflavin and 1.3 mg of niacin.

Yuca, cassava or cas sava ( Manihot esculenta )

It is native to the basins of the Orinoco and Amazon rivers. The tubers are thick hard and brown, and white inside. In Brazil, the consumption of farinha or cassava flour.

Sweet yucca is consumed fried or parboiled. The starch extracted from cassava is known as tapioca. Bitter yucca contains a glycoside that can release hydrocyanic acid. The Indians scrape and press this yucca separating the toxic liquid from the starch; the poisonous liquid is yare.

With the pressed starch the cassabe or cassava is prepared. This consists of large dry cassava flour discs cooked over the fire that are stored at room temperature.

100 grams of the edible portion of cassava contains 143 Kcal, 61.6 g of water, 1.1 gram of protein, 0.2 g of fat, 36.5 grams of total carbohydrates, 2.3 grams of fiber, 29 mg of calcium and 53 mg of phosphorus.

In addition, 100 grams of cassava have 0.7 mg of iron, 70 mg of magnesium, 0.55 mg of zinc, 0.16 mg of copper, 15 mg of sodium, 344 mg of potassium, 0.06 mg of thiamine, 0.03 mg of riboflavin, 0.6 mg of niacin and 35 mg of ascorbic acid.

References

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