In the world of root crops, the Okinawa sweet potato is truly a standout. Its excellent nutrient profile, striking purple hue, and distinct flavor captured the attention of health advocates and food enthusiasts around the world. This vegetable is also a major part of the diet of Okinawans — people who are known to have longer life expectancy.
Today’s post discusses all the things you need to know about these purple Japanese sweet potatoes, their health benefits, as well as how they’re used in Japanese cuisine.
Okinawa sweet potato (Ipomoea batatas) is an oval and tubular-shaped root vegetable that tapers slightly at the end. Its beige and earthy brown-colored skin is rough and bumpy. When you slice it, you’ll see that its violet flesh is sometimes marbled with linear white and lavender marks.
Texture-wise, the Okinawa sweet potato is starchy. Once cooked, you’ll be treated to a very sweet and nutty flavor.
The root vegetable has been enjoying popularity internationally because of the health benefits it brings. Experts from various health organizations highly recommend the Okinawan sweet potato for being remarkably nutritious.
The pigment called anthocyanin is the antioxidant responsible for the purple color of an Okinawan sweet potato’s purple flesh. This very same component is found in red grapes, blueberries, and red cabbage.
In Japan, the Okinawa sweet potato is called beni imo. Some people may ask, "Is Okinawan sweet potato the same as Hawaiian sweet potato?” Yes, it’s the same variety. And in the US state, they also call it uala.
Okinawan people know what’s best for them. Studies have shown that a traditional diet consisted of 85% carbohydrates, with sweet potatoes being a large part of that percentage.
But there’s another reason why the root vegetable is a staple of the Okinawan diet. Because of the island’s location, destructive seasonal storms typically ravaged the island. In the 1600s, its citizens turned to planting sweet potatoes imported by the Chinese.
Okinawan sweet potatoes are not just delicious. They're packed with essential nutrients and a whole lot of other components that have been proven beneficial for the human body. With the advantages these sweet potatoes bring, they are truly an excellent addition to any diet. Below, we list some of the health benefits of this root vegetable.
Since Okinawa sweet potatoes are rich in fiber, they can keep the body’s digestive health in top shape. Eating these root crops will help you get rid of the unwanted wastes in your body, including cholesterol.
By incorporating Okinawan sweet potatoes into your diet, you can support your digestive health and potentially lower your risk of heart disease.
Sweet potatoes from Japan are generally ranked medium to low when it comes to glycemic index. To put it more simply, diabetics can easily incorporate Okinawan sweet potatoes into their diet as they won’t make blood sugar levels spike.
Okinawa sweet potatoes have an abundance of beta-carotene. This substance becomes Vitamin A when the body processes the nutrients. One of the main benefits of Vitamin A is maintaining good eyesight. Regular consumption of these sweet potatoes can help slow down vision degeneration and promote overall eye health.
Okinawa sweet potatoes are often confused with a lot of varieties. In this section, we’ll discuss how they differ from the root vegetables they’re closely related to.
The physical differences between a regular sweet potato and an Okinawan sweet potato are apparent. The former has a darker skin than the latter. Beauregard, the most common sweet potato variety, has orange flesh, while beni imo is always purple-fleshed.
Ube is not the same as Okinawan sweet potatoes. Ube, which is a Filipino term for the country’s local purple yam. The skins of both root vegetables are completely different. Okinawan sweet potatoes have thin skin while the ube’s is almost similar to a bark.
Biology-wise they are also unrelated. Okinawan sweet potatoes are under the morning glory family while ube is a type of yam.
Unlike the light skin and purple flesh of the Okinawan sweet potato, Japanese sweet potatoes (locally known as satsuma imo) have reddish-purple skin and light-colored flesh, which can either be yellow or white.
Both varieties also differ in texture. The Japanese sweet potato is waxy, allowing it to keep its shape after cooking. Okinawan sweet potatoes, on the other hand, are a bit sticky.
Okinawan sweet potatoes and purple sweet potatoes, which are known as Stokes, share a similar characteristic. Both of their flesh is purple-colored. The main difference is their skin. Stokes has purple skin, unlike the Okinawan sweet potato.
When in Okinawa, look for snacks that incorporate Okinawan sweet potatoes. Their natural sweetness makes them the go-to ingredient for sweets on the island. The most well-known snack is called the beni imo tart.
A lot of stores already offer this sweet treat. But if you want an authentic experience, visit a branch of Okashi Goten, the company behind the creation of the original beni imo tart.
If you’re looking for an easy and healthy way to consume Okinawan sweet potato, enjoy it steamed. All you need to do is boil it until it softens, mash it, and then add coconut milk and sugar to taste. But it can also be eaten as it is after steaming.
Others want it baked because its natural sugars bring a caramelized effect to the warm and sweet snack. Discover the flavors of Okinawan Sweet Potatoes in one of our Japanese Snack Boxes!