Commentary for Avodah Zarah 132:6

Rava would have to admit that he holds only like R. Judah. But Abaye could say that all tannaim agree with him. They only disagree in a case where the smell is not likely to go into the bread, either because the bread is cold or the wine is stoppered. Abaye could say that smelling the wine directly through the bung-hole is again a case in which all tannaim would agree that the smell is substantial enough for the act to be prohibited.
I think people should note how two issues are being conflated in this sugya. Abaye and Rava are arguing whether one is allowed to smell prohibited substances. The issue is whether an action is permitted. In contrast, the sources they bring are discussing whether substances are defined by their smell or not. The issue is status of object. These are not exactly the same issue. I believe that what causes the sugya to discuss them simultaneously is the general rule—smell is substantial or not. This is a classic example of how a general rule allows different subjects to be discussed together and for one to effect the other.