3,418. Produce From Which Ineffective Terumah Was Taken
Hilchos Maaser 5:18
If someone salts produce in the field, the obligation to tithe it takes effect. However, if one dips olives into salt and eats them individually, they need not be tithed. If one splits olives so that their liquid will drain out, they need not be tithed. One who removes olives from the vat may dip them in salt and eat them individually, but if he salted and served several olives at once, then they must be tithed. The same rules apply in all comparable cases.
Hilchos Maaser 5:19
If someone takes terumah from his produce in a way that would requires him to take terumah again (i.e., it wasn’t done effectively the first time), the obligation to takes tithes takes effect. One may not snack from such produce until he takes terumah a second time, plus tithes.