Terumot, Chapter Ten, Mishnah Two
1) If an apple [of terumah] was chopped and placed into dough [of hullin] so that it leavened it, [the dough] is forbidden.
2) If barley [of terumah] fell into a cistern of water, though [the barley] stinks up the water, the water is permissible.
Section one: If someone chops up an apple and puts it into dough to use the sugars in the apple as a leavening agent, the dough must be treated like terumah because the apple caused the leavening.
Section two: In this case terumah barley falls into a cistern and rots, thereby causing the water to stink up. The water is permitted to non-priests even though it has the taste of terumah because the taste that it imparts is not a desirable taste. Something that leaves a bad taste does not cause the other food to become prohibited.