TUBERS: CHARACTERISTICS, TYPES, PROPERTIES AND EXAMPLES - NUTRITION - 2025

The tubers are stems feedstock of some species of plants growing underneath the floor and serve for asexual propagation. The plant uses them for its survival during winter or drought, and as a reserve of energy and nutrients for regrowth, during the following growing season.

There are edible tubers and others used in gardening. Among the latter are the Cyclamen, the Sinningia and some begonias. Common food species of stem tubers include potato (Solanum tuberosum) and yam (Dioscorea spp).

Also noteworthy are the ocum (Xanthosoma sagittifolium), the taro (Colocasia esculenta L.), the olluco, the smooth potato, the ruba, the ulluco or melloco (Ullucus tuberosus) and the kohlrabi (Brassica eleracea). Under this definition are some species that arise from a thickening of the roots (root tubers or radicals).

Among the latter are cassava, cassava or manioc (Manihot esculenta); sweet potato, sweet potato, sweet potato or sweet potato (Ipomea batata); celery (Arracacia xanthorrhiza); and 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 below the ground.

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

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

Celery and sweet potato are provitamin A contributors, being the most colored varieties and the richest in this nutrient.

Types

Tubers can be classified into two types: stem and root.

An example of stem tubers is potatoes. Its upper sides produce shoots 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 the 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 in the complete root.

Properties / health benefits

Essential nutrients

The 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-carotenes, 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 digestive and excretory systems healthy.

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

Reduces tissue damage

The nutrients in the tubers act to repair tissue damage. For example, vitamin A improves vision and reduces visual problems. On the other hand, vitamin C repairs cell damage.

Apart from these general nutritional properties, the particular characteristics of some tubers will be discussed below.

Examples

Celery (

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

It cannot be eaten raw, but when cooked it develops a pleasant flavor and aroma. The boiled root is used in a similar way to potatoes. It is served as a garnish, mashed into a puree, formed into meatballs and gnocchis, as an ingredient in cakes or in soups.

Fried chips, cookies and celery flour and starch are made. The latter is highly digestible.

100 grams of the edible portion of celery contains 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 ER 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 (

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 is native to Africa and Asia.

It is consumed in multiple ways: boiled, pureed, fried or canned in syrup. In addition to simple starches, sweet potatoes are rich in complex carbohydrates, dietary fiber and beta-carotene (a provitamin A carotenoid), rich in potassium, low in sodium, and moderate in 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 ER vitamin A, 300 µg total equivalents β-carotenes, 0.11 mg of thiamine, 0, 05 mg of riboflavin, 0.7 mg of niacin and 23 mg of ascorbic acid.

Yam or yam

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

Indigenous people in Guyana 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 thiamine, 0.03 mg of riboflavin, 0.4 mg of niacin and 7 mg of ascorbic acid.

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

Ocumo

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, aro, 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 squash are dark on the outside and contain acrid substances and alkaloids that must be destroyed by heat prior to consumption.

Raw squash should not be eaten due to its high content of calcium oxalate. This gives it irritating properties and can cause temporary muteness.

100 grams of the edible portion of the ocum 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 ER vitamin A, 18 µg total β-carotene equivalents, 0.13 mg of thiamine, 0.02 mg of riboflavin, 0.6 mg of niacin and 6 mg of ascorbic acid..

Olluco

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

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

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.

Likewise, in 100 grams of potatoes 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 thiamine, 0.06 mg of riboflavin, 1.2 mg of niacin, 0.31 mg of vitamin B6 and 20 mg of ascorbic acid.

Taro

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

When raw, it should not be ingested due to the presence of calcium oxalate. Taro is a commonly used ingredient in Chinese and Taiwanese food. The tuber is smaller than the common ocum and is white inside, although externally it shows dark colored concentric rings.

Unlike yams, 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 thiamine, 0.06 mg of riboflavin and 1.3 mg of niacin.

Cassava, cassava or cas

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

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

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

100 grams of the edible portion of cassava contain 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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