I just bought a bread. It looks fresh, no mold or any other marks, but it has a strong smell of vinegar. I toasted and ate some, and it tastes totally fine... just the smell... Anyone know what this is and whether I can do something about it. Thanks!
I'm guessing this is sourdough bread, naturally leavened. The tastes can vary because the fermentation is natural and therefore a little bit random. The microbiome is different in every bakery so two loaves from different bakeries will always taste different even if they have the same starting flour and water. The sourness of the bread comes from the fermentation duration and the microbial culture of the starter.
This is the natural breakdown process of the white bread. It's not supposed to do this before expiration date, but it happens. You should contact the bakery and inform them (they will usually replace it). Mine was Mrs. Baird's Hamburger buns, smelled and tasted of strong vinegar on June 18th with an Expiration Date of Jun 21st. This is nature's way of saying Don't Eat me! It can cause illness, but nothing that lasts, unless you are allergic to mold.