when smoking meats when would a mop or a bast be used.? when grilling I use a beer mop on larger pieces of meat when ever I turn it and on the rotissiere when ever I put more coals or I think I should. I would guess that when using a dry rub. you would not bast or mop. Not sure. but when not using a dry type rub you would mop / bast a lot.. or in smoking you just do not use bast / mops.than you..