By: Halacha Yomis Team of OU KOSHER
May one grind coffee beans on Shabbat?
Rav Yaakov Emden zt”l (Mor U’ketzia 495) writes that one may grind coffee on Yom Tov with a small hand grinder. Furthermore, he writes, it may be permissible to grind coffee on Shabbat if one does so with a shinui (in an unusual manner). This is because roasted coffee beans are edible, and there are opinions that allow grinding edible cooked food. He offers other arguments as well to permit grinding with a shinui.
However, Rav Ovadya Yosef zt”l (Yabia Omer OC 4:45:2) strongly disagrees with this leniency. He writes that according to the ruling of Shulchan Aruch (321:12) that we forbid fine chopping of fully edible vegetables, there is no basis to permit grinding cooked foods, even with a shinui. Furthermore, he writes that not one of the later poskim quote the opinion of Rav Emden to permit any form of grinding coffee on Shabbat, and surmises that his halachic position was never accepted.