A while ago I tried to research why every Subway has an awful smell. My kids love the smell but for me, it smells like some rancid preservative. The best and most likely reason I could find is, the smell starts in the proofing room where bread is thawed out and moisturizes the bread. Defrosted dough alone wouldn't smell anything like the Subway bread though, so I researched what they put in it. Apparently they don't use preservatives but they do use vitamins. Sounds like the vitamins are reacting during the fermentation process.
