From Saiki K’s twitter on 19 July, 2017:
The other day we introduced「Saiki Kunio’s Coffee Jelly」, and this is the real thing‼
It was such a splendid treat that the staff went… Ohh? It was also a very popular item on the set?
Admin’s note: Personally this is my favourite brand of coffee jelly! I really hope they do some kind of collaboration…