Purple Japanese Sweet Potatoes
Inventory, lb : 0
Description/Taste
Japanese purple sweet potatoes are small to medium in size and are long, slender, and oblong in shape, averaging 10-12 centimeters in length and weighing around four ounces each. The tuber may be slightly curved, and both ends taper to a slender point. The thin, smooth skin ranges in color from red-brown, dark brown, to purple, and there are a few shallow eyes and root hairs present across the surface. The flesh is vibrant purple with some white and violet striations that disappear when cooked. Japanese purple sweet potatoes have a somewhat dry and starchy texture that becomes creamy when cooked and offers a mildly sweet taste with notes of chestnut.
Seasons/Availability
Japanese purple sweet potatoes are available in the early fall through winter.
Current Facts
Japanese purple sweet potatoes are botanically classified as Ipomoea batatas and are members of the Convolvulaceae or morning glory family. Also known as Murasaki Imo, which means “purple potato” in Japanese, there are several varieties of Japanese purple sweet potato including Purple Sweet Lord and Ayamurasaki. Japanese purple sweet potatoes are used in a variety of culinary applications including desserts and snack foods and are valued for their sweet flavor and high antioxidant content.
Nutritional Value
Japanese purple sweet potatoes contain dietary fiber, vitamins A and C, and minerals like calcium, magnesium, potassium, and zinc. The flesh also contains anthocyanin, a naturally occurring antioxidant that gives the tuber its purple hue.
Applications
Japanese purple sweet potatoes are best suited for cooked applications such as steaming and roasting. When boiled, they will lose their purple hue so to retain their vibrant color, they should be roasted or steamed. In Japan, they are commonly used in snack foods, juices, bread, and confectionaries, as well as in desserts like ice creams, pies, and cheesecakes. Japanese purple sweet potatoes are also popular for Imo Yokan, a Japanese jelly cake made with sweet potato, agar, and sugar. Japanese purple sweet potatoes are commonly dried and turned into powder for use as a natural food coloring. They will keep up to two weeks when stored in a cool, dark, and dry place.
Ethnic/Cultural Info
All varieties of sweet potato are valued in Japan as a healthy starch and are used in a range of applications. A popular traditional alcoholic beverage in Japan called Imo-shochu is derived from sweet potatoes and involves steaming the tuber and mashing it in with a rice, yeast, and water mixture. It is then fermented and distilled to create the alcoholic beverage. Versions of the drink made with Japanese purple sweet potatoes offer tasting notes of wine and yogurt.
Geography/History
The first sweet potatoes were brought from China to Japan in the 1600s and have been a staple food since the 1700s. Japanese purple sweet potatoes have been propagated since the 1980s and are the result of careful breeding. Today they are commonly grown in the Kagoshima and Kyushu Prefectures in Japan. Japanese purple sweet potatoes can be found in specialty markets in the United States and Japan, though availability may be limited.
Recipe Ideas
Recipes that include Purple Japanese Sweet Potatoes. One is easiest, three is harder.