The nutritional value of yam and its culinary uses

Discover all the benefits of yam or Yam, a tuber from Africa and particularly widespread in Mexico, but not to be confused with the American potato

Yam, also referred to as “igname“, is a starchy tuber produced by plants of the genus Dioscorea. The term “yam” refers both to the plant and the edible tuber.

The word “igname” is derived from the Portuguese inhame or the Spanish ñame. The Dioscorea plant is a perennial herb with heart-shaped leaves and yellow-green flowers.

Yams prefer rocky and dry land and are primarily found in Mexico, Texas, Central Africa, and eastern China. They are also grown throughout the Caribbean, Latin America, and Oceania.

Types and local characteristics

There are a great many yam varieties, differing with the region of their growth. Unlike cassava, which is also called tapioca or manioc, most of the yam varieties are non-toxic. However, there are exceptions: the tubers of bitter yam varieties contain potentially harmful substances neutralized by soaking them in salt water.

Normally, bitter yams are not eaten except during famines. In Malaysia and Indonesia, these bitter varieties are utilized in the preparation of potions and poisons.

How do yams differ from sweet potatoes?

What is called for “yam” both in North America and in Québec is actually a sweet potato. Sweet potato flesh can be white, orange, and even purple depending upon the variety. The orange flesh variety, which was only introduced to the U.S. several decades ago was labeled as “yam” by the producers and distributors who wanted to differentiate it from the white flesh variety. This term came from “nyami,” an African word.

Today, the U.S. Department of Agriculture mandates that any product labeled as “yam” should also bear the term “sweetpotatoes.” But even with these regulations, the general perception of yams remains synonymous with sweet potatoes.

A real yam is quite different, though. It boasts rough, scaly skin, is less sweet, and contains much less beta-carotene. Its flesh also varies depending on the variety.

Nutritional benefits of yam

Yams are an important food source in Africa, which also supply proteins. In tubers and roots, yams and potatoes have the highest protein content, about 2% of the weight of fresh product. However, they are deficient in some essential amino acids and must be consumed in association with other foods for a complete diet.

Yams are a good source of potassium, vitamin B6, and vitamin C. An serving size of 3.5 ounces (100 g) contains about 110 calories. They are rich in manganese, thiamine, and dietary fiber, with low content of fat and sodium. In general, yams are lower on the glycemic index than potatoes, giving them a better place regarding healthy carbohydrates.

Source: Nutrition Data

Nutritional Information Per 3.5 oz (100 g) of Raw Yam

In West Africa, and especially in Niger, yams constitute a leading staple food item and bring in over 200 daily calories to more than 150 million people. They are a good source of earnings for farmers, too.

How to cook yam

Yams are very hardy and available all over the year, hence providing a dependable source of food in Africa. They require cooking before consumption. Some of the ways of preparing yams include boiling, frying, and roasting. The tubers are usually eaten with savory sauces or included in sweet dishes.

Yams, dried and ground into powder, are used in soup and pudding preparations in Nigeria. In the Philippines, ube is a purple yam variety used in the ice cream halo-halo. Japanese people consume yams raw and grated.

The rhizome of some varieties of yam is processed for the extraction of diosgenin used in manufacturing corticosteroids and oral contraceptives.

Yam in contemporary diets

With the passing years, yams have also been adopted into modern diets because of their low glycemic index and high fiber content. They are also very popular in vegan and gluten-free cooking. Yams can serve as a good base for creamy soups, and this is usually seasoned with spices like ginger and turmeric. They can also be used to make gluten-free gnocchi, pasta, or plant-based burger patties. Yam flour has also become increasingly used as an option in bread and pastry products catering to clients with certain food intolerances or alternative grains.

Traditional yam recipes

Yams feature in traditional recipes from different parts of the world. Boiled and pounded, pounded yam is a favorite food for Nigerians; it is prepared until it is smooth, elastic, and usually eaten with spicy stews like egusi or okra soup. The purple yam ube is used to create the Filipino dessert called ube halaya: sweet cream with cooked yam, condensed milk, and sugar, normally used as a topping or filling in pastry.