Let’s say you forget about it for a week. Is it dead? No way. It’s just… different. The dough might turn a little gray or develop a faint beery smell. That’s not spoiled, it’s transformed. You can absolutely use it, but expect a tang similar to sourdough.
If you see mold—green, fuzzy, or black spots—toss it immediately. That’s not flavor, that’s a science experiment gone wrong. Otherwise, a slightly funky smell is okay. Your nose knows: if it smells like bread gone bad, trust your gut. If it smells like a brewery, you’re golden.