All About Purple Sweet Potatoes

The Skinny on Purple Sweet Potatoes Sometimes Called Purple Yams

Purple sweet potatoes
Shizhao/Flickr/CC BY-SA 2.0

If you've never cooked with a purple sweet potato before (sometimes mistakenly called a purple yam), the first time you cut one open, it will probably cause you to gasp.The inside is beautiful with its light purple and juicy flesh in complete contrast to its dull brown exterior.

Where Do They Come From?

Sweet potatoes with brown, red-orange or white skin and orange or white flesh, are native to Colombia and southern Central America.

After Columbus' discoveries, they were brought to Asia, and varieties with white skin and speckled pale purple flesh were developed on the Japanese island of Okinawa.

Today, they are widely grown in Hawaii and exported to the United States mainland, where they are popular with Asians and Latinos.

How Do They Taste?

Purple sweet potatoes have a rich, almost winey flavor but are denser and drier than regular sweet potatoes.

When cooking, they will take longer than regular sweet potatoes. It will take anywhere from 90 minutes to 2 hours at 350 F to make them pleasingly moist.

Where Their Color Comes From

The deep color of purple sweet potatoes comes from anthocyanins, the same pigment that gives cherries, strawberries, purple carrots and other vegetables their color. 

Purple Sweet Potatoes vs. Purple Yams 

  • The purple Okinawan sweet potato is grown underground and is similar to Western sweet potatoes. From the outside, this purple sweet potato looks the same but cut one open and you'll know the difference. They can be found across North America at an Asian or Chinese market, and even at some regular grocery store chains. Look for it in the fall and winter.
  • Filipino ube or ubi (not usually available in the U.S.) have darker, rougher-looking skin and are yams, not sweet potatoes. They grow on a vine above the ground. This vegetable is a major crop and food source in the Philippines. It also is made into a powder which is then used in Filipino desserts (you'll know them by their bright purple color).

    Purple Sweet Potato Nutrition

    The same anthocyanins that make food look pretty are touted to also have beneficial health effects—eradicating free radicals that have been attributed to causing cancer, protecting the liver, and lowering blood pressure. They are high in potassium, B6, vitamin C, fiber, and antioxidants—purple sweet potatoes are truly one of nature's wonders.

    Cooking With Purple Sweet Potatoes

    Purple sweet potatoes are wonderful boiled, steamed, or baked alongside regular sweet potatoes.

    They can be used in many of the same ways you’d use a regular orange or white potato, and the colorful result puts a fun spin on mashed potatoes, fries, and soups.

    For a delicious way to cook with them, see this baked sweet potatoes and purple yams recipe.