What, if any, are essential differences between mincing and grinding?
I tend to associate mincing with soft foods (other materials?) such as meat. In particular, Merriam Webster has the following (for the transitive verb):
a : to cut or chop into very small pieces
b : to subdivide minutely; especially : to damage by cutting up: to utter or pronounce with affectation
a: archaic : minimize
b : to restrain (words) within the bounds of decorum
Here 3.a points out the etymology and maybe the technique of mincing, while 3.b suggest metaphorical usage (mince one's words).
Grinding might connote harder materials, such as pepper or nuts. Again from MW (transitive verb):
to reduce to powder or small fragments by friction (as with the teeth)
to press together and move with a rotating or back-and-forth motion—see bruxism
Etymonline gives OE grindan "to rub together, grate, scrape" and earlier roots with the same meaning.
Apparently, one can also grind beef, for example.
Is there any difference in the technique of mincing and grinding different materials? Or in the intensity of crushing? In the accompanying sounds? (Hopefully grinding one's teeth is mainly about the sound, not producing anything.)
Or is it just a matter of collocation — mince is customary with some materials, grind with other materials?