Is Grinding Permitted on Yom Tov?

Greetings,

1. There is also a prohibition of grinding on Yom Tov (see Shulchan Aruch, siman 495, seif 2, and Mishnah Berurah, seif katan 13). Therefore, any kind of food that can be ground before Yom Tov, and doing so will not cause its flavor to weaken, may not be ground on Yom Tov unless a שינוי is made in the manner of grinding (Shulchan Aruch, siman 504, seif 1).

2. In any case, if it is a type of food that, were it ground before Yom Tov, its flavor would weaken, then according to Sephardi custom it is permitted to grind it on Yom Tov with a grater and the like, without any שינוי (Shulchan Aruch there, seif 1). However, according to Ashkenazi custom, it should be ground before Yom Tov. And if one forgot to grind it before Yom Tov, one may grind it on Yom Tov with a שינוי (Rema there, and Mishnah Berurah seif katan 11). For example, if one was accustomed to grinding over a plate, one should grind over a cloth or a table (Mishnah Berurah seif katan 19).

3. If it is a food that, were it ground before Yom Tov, its flavor would weaken entirely, then according to all opinions it is permitted to grind it on Yom Tov without any שינוי (Mishnah Berurah seif katan 11, and Shaar Hatziyun seif katan 18). Therefore, it is permitted to cut vegetables very finely on Yom Tov without any שינוי (Mishnah Berurah seif katan 19, and Shaar Hatziyun seif katan 36).

With blessings,

Hillel Meirs