Seasonal spotlight: satsuma-imo
To an American, autumn in Japan is missing a number of the items and customs that make this particular season unique. Stores aren’t displaying shiny new school supplies because children here begin school in spring, Halloween decorations are everywhere but you have to look hard to find a little kid in a costume because Japanese people think that knocking on a stranger’s door and demanding candy is really weird, and obviously the Japanese don’t celebrate Thanksgiving.
But there is one thing that, once you spend a single autumn in Japan, will symbolize the season for you forever: yaki-imo (roasted sweet potato). Once summer is over this delectable treat starts showing up in convenience stores and grocery stores everywhere, but the best way to eat it is to buy a freshly roasted sweet potato from one of the many yaki-imo trucks that cruise around announcing their presence with loud recordings of some guy warbling “yaakkkiiii-immmoooo….” Or at least, that would be the best way if these trucks ever showed up when I wanted a yaki-imo. I seem to have terrible luck because the only time I encounter one is when I’m coming home from a restaurant and am already full, and inevitably when I do hear that siren call I’m either at home in my pajamas or hurrying to get somewhere. There has only been one instance in my life when I remarked “I wish I had a yaki-imo” and a truck actually serendipitously appeared, and that was when my friend Maya and I were walking aimlessly around the red light district of Kabuki-cho for some reason. But I digress.
I was looking for a video of a yaki-imo truck when I stumbled across this clip from Sazae-san, which is probably Japan’s most famous animated series. The plot of the episode involves Katsuo, the troublemaker of the Isono family, geting money from his mother to buy yaki-imo and deciding to roast his own (in a pile of fallen leaves) instead to make a profit. Good-natured hilarity ensues. (The yaki-imo truck shows up at about 1:30.
Roasted or not, sweet potatoes (satsuma-imo) are one of the true pleasures of fall in Japan. According to Wikipedia, sweet potatoes were originally brought to Japan from the Americas and were called by a variety of names as they spread north throughout the different islands. Apparently once the potatoes made to Honshū (the main island of Japan) from Kyūshū (the southernmost island) they came to be called “satsuma-imo” after Satsuma, which is the name of a former domain and province in Kyushu. (In case you’re wondering, none of this has anything whatsoever to do with the citrus fruit known in English as a “satsuma” which is called an entirely different thing in Japanese.)
I am not at all ashamed to admit that I adore satsuma-imo and find them to be significantly tastier than American sweet potatoes. They are so sweet and good that eating them feels almost like having dessert. Besides the old standby of satsuma-imo gohan (rice cooked with sweet potatoes), I like put them in miso soup or curry, simmer them with kelp or lemon to include in a bento, or eat them as tempura. Satsuma-imo are also the principle ingredient of kuri kinton, an almost overwhelmingly sweet confection that is an indispensable part of osechi (traditional food served over the New Year holidays). However, they’re delicious in Western-style desserts too – I once made a satsuma-imo and apple pie that was quite good.
There’s no reason to peel satsuma-imo before eating them because the skin is a big part of their visual (and nutritional) appeal. Depending on what looks fresh I either buy the big satsuma-imo the size of an Idaho potato or the smaller ones that are about the thickness of an American carrot but half as long. Like all vegetables of this type satsuma-imo can be kept for quite a while in a cool, dark location. Eaten in reasonable quantities they’re not even that high in calories: according to the Glico Nutrition Navigator a 100 gram serving of steamed satsuma-imo has only 131 calories but contains 3.8 grams of fiber, 490 milligrams of potassium, and 1.2 grams of protein.
I’ll be posting my recipe for sweet potato rice with black rice this Wednesday. Until then, here are a few recipes featuring satsuma-imo I’ve gathered from around the Internet. Some are fairly traditional Japanese dishes while some offer a more Western way of using this vegetable.