I’m so grateful that Japanese satsumaimo have appeared on the scene in America. My Whole Foods has them and my local Japanese farmer has them as well. If you haven’t seen them, the most notable feature is that the inside is a pale kiiro rather than orange. If you scratch the surface of a satsumaimo you can see the color inside and assure yourself that you have the Japanese variety.

Satsumaimo sings in the season. Literally. One of the more nostalgic sounds of autumn and upcoming fuyu comes from the trucks roaming city and suburb streets selling roasted satsumaimo. In the winter you buy it as you walk home from the train station, firstly to warm your te as you walk and secondly to eat. Roasted satsumaimo are the best.

And then there are the daigaku imo that you see being sold in tiny shops that may or may not sell other sweets. I’ve never liked them, but I know they are pieces of sweet potato deep fried and dipped in sugar or honey. Why daigaku, which means university?

It turns out that they were first sold near universities in Tokyo or areas where university students lived. Students back then were notoriously poor and couldn’t afford much. So this was an affordable and filling snack for them. These days students seem much wealthier, but everyone still likes satsumaimo.

One of my children’s favorite books featured satsumaimo and a farting contest. Because if you eat a lot of them, you get pretty gassy. In this book the children eat as many as they can and then use their onara to rise into the sky.

Last week I was in Cambridge and had access to an Asian pastry shop. And yes, the only thing I wanted was sweet potato pastry. Note the black sesame seeds that you also see on the daigaku imo. They just seem to go together with satsumaimo. Tengoku!

• satsumaimo – サツマイモ　sweet potato. Literally a potato from Satsuma
• kiiro – 黄色　yellow
• fuyu – 冬　winter
• te – 手　hand or hands
• daigaku imo – 大学芋　sweet potatoes deep fried with either sugar or honey. A favorite treat of students
• onara – おなら　fart
• Tengoku – 天国　Heaven. Used in this case much as “heavenly!”