28 October 2015

The other day I was eating a yam and wondered where the name “yam” came from.  The Oxford English Dictionary said the word is from West Africa and it’s not the name of the plant I was eating.

True yams are in Dioscoreaceae, the Yam family. Native to Africa and Asia, they’re an important food staple with many cultivated varieties. Our yams were named by African slaves who saw the resemblance to the yams back home.  A true yam (African type) looks like this.

North America has native members of the Yam family but we don’t find them in the grocery store.  Wild yamroot (Dioscorea villosa) is common in western Pennsylvania and is most noticeable in spring when its pleated leaves grow in a whorl near the ground.

The “yams” we eat are sweet potatoes (Ipomoea batatas), members of the morning glory family, Convolvulaceae.   Their flowers show what family they’re in.

Unfortunately sweet potatoes are labeled Yams in the grocery store because of USDA rules that say:  Sweet potatoes that are white inside = “sweet potato,” orange inside = “yam.”  I must look for the word “yam” to find an orange sweet potato in the grocery store.

I have never seen a white-inside sweet potato. Have you?

Read more here at the Huffington Post: What’s the difference between sweet potatoes and yams?

(photos from Wikimedia Commons.  Click on the images to see the originals)