Grating Garlic on to Bread Crust
Shalom, Are you allowed to grate garlic on a bread crust on Shabbos [this is an old Russian traditional food]?
The Mishna in Tractate Shabbos [73a] records the 39 avos melachos, the 39 acts of productivity prohibited by the Torah on Shabbos. The first group of melachos are the activities involved in making bread from planting to reaping to baking. Included in this category is the melacha of Tochein, Grinding. This refers to the grinding of the wheat in to flour in the bread making proocess. Grating a peice of garlic would be included in the melocha of grinding and thus prohibited. Garlic would likley fall under the category of foods that are unedible without grinding and as such would be a Torah prohibition according to all opinions.
The Rama [O:C 321:12] brings the opinion of some early authorities that just as we find with the melocho of Borer that if done for immediate use it is permitted [with certain conditions], the same would apply to Tochein, Grinding.
This leniency would not apply here for 2 reasons. Firstly, the Mishna Brura [s.k. 45] requires that even when for immediate use, the peices be ground to larger than usual grinding. This is in deferance to the opinions that disagree with the leniency of the Rama, and hold Grinding is prohibited even for immediate use. Grating garlic creates miniscule pieces.
In addition the Biur Halacha [s.v. midi] explains that just as the leniency by Borer is only when done by hand, the same would apply to grinding. Hence using any grater or grinder which is a tool for Grinding would be prohibited in any event.
If the garlic could be cut with a regular knife to slightly larger peices [each garlic into 2 or 3 pieces], this would be permitted when done immediately prior to eating.