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About Aomori Nagaimo


  1. Aomori-grown nagaimo
  2. Aomori-grown nagaimo and its health benefits
  3. Nutrition and medical benefits of the nagaimo
  4. Nagaimo makes my hands itch.
  5. What to do with sprouting nagaimo
  6. How to Store
  7. How to distinguish fresh nagaimo History of the nagaimo
  8. History of the nagaimo

1. Aomori-grown nagaimo

Nourishing and nutritious vegetable with tender flesh from the top two producers in the country, low in bitterness and rich in protein, minerals and vitamin C.

2. Aomori-grown nagaimo and its health benefits

The yam (yamaimo) is said to have come originally from China. It was imported to Japan a long, long time ago, and has been grown in Japanese fields ever since.
Although today the yam is produced in many different parts of Japan, Aomori-grown nagaimo has a nationwide profile and reputation, and is consumed by people throughout Japan, while being well known as a special product of Aomori Prefecture, which is actually the largest producer of the nagaimo in Japan.
The nagaimo is known to be not only high in nutrients but also easily digestible.
As such, it has been used as a tonic vegetable since ancient times. The major nutrients contained in the nagaimo are carbohydrates, potassium, vitamin B1 and dietary fiber, in addition to the micronutrients choline and saponin. These nutritive elements are said to help relieve fatigue.

3. Nutrition and medical benefits of the nagaimo


The Japanese generic name for yams is yamaimo. The nagaimo is an early-season, long-root variety of yamaimo. While the ichoimo is a fan-shaped variety and the yamatoimo is a block variety.
The nagaimo is suitable to be grown in cold climates such as Aomori Prefecture. In fact, the southern part of Aomori Prefecture is Japan's largest producer of the nagaimo.
Aomori-grown nagaimo enjoys a nationwide reputation for their quality and taste,and are used in a wide variety of recipes, as one of the most well-known specialties of the prefecture. Moreover, the nagaimo, which is sometimes referred to as "mountain medicine" and is used for medical purposes in Chinese medicine, is also known to help reduce high blood pressure, regulate digestion and relieve fatigue.

[Medical benefits]

  • Helps lower cholesterol levels.
  • Helps prevent high blood pressure.
  • Acts as a tonic for general vitality, including male sexual potency.

Since the nagaimo contains high levels of amylase and other digestive enzymes, it helps to digest starchy foods, for example, rice eaten with it.
In addition, the viscous substance peculiar to the nagaimo is known to help the body make better use of proteins.

4. Nagaimo makes my hands itch.

When you peel or touch a nagaimo, it sometimes makes your hands itch.
This is said to be a kind of allergic reaction. If this is the case, you can soothe the itching by applying lemon juice to the itching part or rinsing off the substance with diluted vinegar.
You can also prevent itching by soaking nagaimo in vinegar water before cooking.

5. What to do with sprouting nagaimo

Unlike potato sprouts, nagaimo sprouts are not poisonous. Therefore, you can eat sprouting nagaimo simply by removing their sprouts. However, as these sprouts use nutrients contained in the nagaimo to grow, it is advisable to remove the sprouts and cook the nagaimo as early as possible, before the sprouts grow large.

6. How to Store

The nagaimo is among the most perishable yams. Even whole nagaimo, which keep for a relatively long time, should be wrapped up in newspaper and stored in a refrigerator or another dark, cool place. By doing this, they will remain fresh for two weeks or so. However, once exposed to the sunlight, their peels will quickly turn dark. The cut edges are particularly perishable. Therefore, it is recommended that cut nagaimo be wrapped in plastic wrap, stored in a refrigerator and used within one week. Grated nagaimo can be kept in a freezer. Place grated raw nagaimo flat into a storage case and store it in a freezer. Then you can break off the amount you need each time, leave it to thaw at room temperature, and eat it without cooking it.

7. How to distinguish fresh nagaimo

Fresh nagaimo have a smooth, resilient surface, free from flaws and spots. Another key is to choose one with a whitish skin, rather than a reddish skin.

8. History of the nagaimo

The nagaimo is produced mainly in the areas around the South China Sea and the Far East. According to ancient Chinese records, its use originated around 2000 BC, when the plant was said to have been first used for medical purposes under the reign of the legendary Emperor Shennong (The Divine Farmer).
This suggests the long history of humans cultivating the plant for their use. The nagaimo originally came from Yunnan Province, Southern China, and later spread northwards (Northern China, North Eastern China, Korean Peninsula, and then to Japan). The nagaimo is one of the oldest plants cultivated in Japan. In fact, its cultivation in Japan is said to date back to the Late Jimson Period, when even slash-and-burn farming of millet and upland rice was yet to be seen.
Aomori Prefecture, particularly its southern part, has quite a long history of cultivating the nagaimo, while the rest of the prefecture also began to grow it later on a small scale. However, around 1964, the introduction of trenchers brought about a dramatic expansion in the plant's growing area in the prefecture, resulting in Aomori Prefecture's emerging as one of Japan's largest producers of the nagaimo.

Eat Aomori-grown nagaimo and become healthier.
Publishing day 2007.2.3

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