'Imo senbei'

It's made from sweet potato.

(from right to left)
'Imo Senbei'
'Imo Kenpi'
'Imo Yokan'
'Anko-dama'
Ashinano, Hitoshi. 1998. Yokohama Kaidashi Kikou. Chapter 33. Vol. 5, Page 19, Panel 2.

An 'imo senbei' is a cracker made from sweet potato. There are two kinds of imo senbei: "deep-fried" and "toasted".

Deep-Fried Imo Senbei

These are deep-fried imo senbei. Sugar-coated deep-fried sweet potato slices. They may look like potato crisps but these are thicker, harder and sweeter.

Toasted Imo Senbei

These are toasted imo senbei. Sugar-coated toasted sweet potato slices.

Plain Ordinary Senbei and Imo Senbei

Usually a 'senbei' is a cracker made from rice but an 'imo senbei' is made from sweet potato.

This is not an imo senbei. It is just an ordinary senbei. It is made from rice.

Conclusion

Rice seems to be rare in Alpha's world.

Appendix A: Other sweets on the banners

Imo Kenpi

An 'imo kenpi' is a long, thin piece of sweet potato fried in oil and coated with sugar. It is the same as fried imo senbei except for shape.

They may look like French-fries but imo kenpi are harder and sweeter.

Imo Yokan

An 'imo yokan' is a brick-shaped cake made from sweet potato. It is made by steaming sweet potato, mashing it, adding sugar, and shaping.

Anko-dama

An 'anko-dama' is a ball-shaped confection made from adzuki (azuki). Above ones are paired and coated with transparent jelly (agar).

Appendix B: Imo yokan and anko-dama shop

Iseya

I bought some imo-yokan and anko-dama at a shop named Iseya, which is located at Sugamo, Toshima-ku, Tokyo Japan.

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