Since I added dried goji berries (from the tree Lycium barbarum) to my oatmeal I noticed that the air from my nose smells like dried pus in the morning.
But I have to pull down my philtrum and my lower jaw and form an 'o' with my mouth and breath through it. This way you can smell your own breath which is normally cancelled out by your brain.
I assume there is some chronic low-grade infection in our sinuses and the goji berries have an immunomodulatory effect.