My favorite type of shochu is an imojochu, or sweet potato shochu. It comes in a wide variety of aromas and flavors. Some can be really funky and others very smooth. Fuutan is on the easy-drinking and light side. This is a great starter shochu if you are interested in sweet potato shochu but are not too adventurous. Fuutan can be had on the rocks or with hot water (oyuwari), so a good shochu to have anytime of the year.
What makes Fuutan unique is that it uses a sweet potato called kurikogane. Most sweet potato shochu is made from a variety called koganesengan. Kurikogane is a unique sweet potato, not often found.
Fuutan
25 degrees alcohol
base ingredient – kurikogane sweet potato
koji – kuro koji (black koji)
Fuutan Genshu is the undiluted version (most shochu is diluted with water to bring the alcohol down). At 36 degrees it is on the high side for shochu. I don’t come across this as often and would have this one on the rocks. If shopping for this, look for the kanji for genshu on the label. 原酒
Fuutan also ages a small amount of bottles, either three or five years. I haven’t had the pleasure of trying these, but typically as time passes the shochu becomes softer and more gentle on the palate. These bottles are numbered on the label.
Fuutan is made by Fukiage Shochu in Minami Satsuma, Kagoshima.
Food Sake Tokyo 
Just curious which imojochus you might recommend to someone who appreciates the more “funky” or “adventurous” side of the shochu world.
Some that are on the funky side include Kurokirishima or Shiranami. But, when I am really in the mood for something funky, I go not to imojochu, but awamori. In particular, I love Shirayuri 白百合, which reminds me of Minnesota lakes. Something swampy about the aroma, and great on the palate as well. For some reason I have found some of the awamori to be more bold on the palate. Cheers! Yukari
Thanks. I’ll give those a try. It looks like they can all be easily obtained from Rakuten.
If you want to do an interesting tasting, consider getting Tominohozan which does an imojochu from kikoji, or yellow koji, and try it with Kiccho Hozan imojochu which is made from kurokoji, or black koji. This is a great way to see how the different koji affect shochu. Cheers! Yukari