Tuesday, June 21, 2011

Baked Purple Yams or Okinawa Purple Potatoes

I recently did a post on the differences between sweet potatoes and yams and, as part of that post, featured purple yams, which are really Okinawa purple potatoes, a sweet potato. I boiled the purple yams in that post and found that I did not like them as well as the jewel yams or Nancy Hall sweet potatoes. However, I read that boiling, as opposed to baking, takes much of the sweetness out of the sweet potato, so I decided to give the purple yams another try - this time baked. Below, the two larger purple yams. 
I pre-heated the oven to 400 degrees and put on three purple yams. 
Note the difference in size and color between the two not wrapped in foil. As with the last time I had purple yams, I found the smaller ones to have a more vivid and concentrated purple color. Two were stabbed several times with a fork, but otherwise just placed on a baking sheet. One was placed in foil and stabbed with a fork. Some website Judy looked up said that the sweet potato cooked in foil really cooks differently and that it takes longer for them to cook, thus the reason for trying it both ways. I pulled out the smallest purple yam after about 15 minutes. 
It was cooked, but was still pretty firm. I added butter and some salt and, Wow!, it was so much better than boiled it was hardly the same creature. 
Even with the thick texture it was wonderfully sweet and good. I left the other uncovered purple yam in for another 15 minutes and then pulled it out. 
It was more cooked and mashed easily (and note the less uniform purple color). I put on butter and salt and it was just pure heaven. 
It was sweet and had a pleasing texture, something I could eat regularly. I cooked the yam in the foil for another 15 minutes. 
Note the moisture leaking from the fork holes after removing the foil. It was much more moist and smashed very easily. 
It did have a different texture and a different taste. I didn't like it as well as either of the other baked yams without foil, no matter how long cooked, although it was still good. 
You can tell, just from looking at the pictures, how the texture changed from baking without foil, shorter to longer, and baking with foil. I am now converted to the idea of baking sweet potatoes, I am converted to the purple yams, which I did not care for when boiled, and I plan to eat them again in the future. 


  1. Those look delicious. I love that color. Unfortunately, I haven't been able to get starts for Okinawan purples (I call them sweet potatoes) lately. Kitazawa seeds can't send them to California anymore. My last ones got eaten by gophers a few years ago. They were very tasty. Do you know here can I get one or two for sprouting? Thanks, Brian

    1. Try an Asian market. I have found that they have a better selection than most traditional supermarkets.

  2. I got some at the Asian market already cooked and ever so delicious! But next time I want to cook them myself. I am confused by your article, which is the best method? 400 degrees for 15 minutes only? That seems very short time. Assuming these are the smaller ones? Can I cook them at 350, like regular sweet potato, which I used to do for 1 hour?

  3. I bought some purple yams in Ottawa, Canada, and baked them much like you did. We couldn't eat them. They tasted like iodine or ink... very bitter and acrid. Terrible! Either we got something entirely different from the usual purple yam or ours went bad.

  4. I thought the purple yam is a, well, a yam, and the okinawan purple sweet potato is.. you know. I guess they are difficult to tell apart? (I've never seen either of them at the store!)

  5. Steaming the potato is another great method that I highly recommend!