Before us is Mishnah 4 in the tenth chapter of Maseches Terumos - the second Mishnah dealing with the subject of aroma and the absorption of scent.
The case before us:
An oven that was heated with cumin of Terumah. That is, the fuel burning beneath the oven is cumin, and for the purposes of our discussion it is cumin of Terumah that one is permitted to burn (cumin that had become tamei and belonged to Terumah).
Cumin is a type of spice, and when it is burned it gives off an extremely strong aroma. It follows that if one bakes bread in an oven whose fuel is burning cumin, the bread will absorb a powerful cumin scent. And this cumin is cumin of Terumah, which is forbidden to non-kohanim. The question, then, is what the status of the bread is: does the loaf, saturated with the smoke of the cumin to the point that it takes on its taste, itself become forbidden to non-kohanim?
The halachah:
The answer is no. The halachah here follows the ruling of the previous Mishnah. In the previous Mishnah, Rabbi Meir and Rabbi Yehudah disagreed, whereas here we rule directly like Rabbi Yehudah and Rabbi Yosi, that a scent is not milsa - a scent is not considered anything substantial as far as the prohibition is concerned.
And in the language of the Mishnah:
"Tanur shehisiko b'kamon shel terumah v'afah bo" - an oven heated by burning cumin of Terumah, and they baked bread inside it.
"HaPas muteres" - the bread remains permitted, even though it is saturated with that very taste and scent.
"She'ein ta'am kamon ela rei'ach kamon" - there is no actual taste of cumin inside the bread, only the scent of cumin. The aroma on its own is not milsa, it is not something significant enough to forbid the bread.
In summary: an oven that was heated with cumin of Terumah, and the bread baked in it absorbed its scent - the bread is permitted to non-kohanim, since it contains no taste of cumin but only the scent of cumin, and a scent is not milsa. This is the halachah.