Rim (cornicione) did not inflate
Affects qualityA rim that won't puff was usually deflated during shaping, baked in too cool an oven, or short of fermentation gas.
Ask yourself
- Was the rim pressed or touched while shaping?
- Is the oven hot enough for the intended style?
- Was the dough fermented long enough to build sufficient gas?
Likely causes
- #1
Rim was deflated during shaping
Generally acceptedPressing into what should be the untouched rim releases the trapped gas that would otherwise puff during baking.
- #2
Oven temperature too low
Generally acceptedA high, fast bake is what causes trapped gas to expand rapidly before the crust sets; a slow bake lets gas escape before it can puff.
- #3
Insufficient fermentation, leaving too little gas in the dough
Generally acceptedA dough with limited gas production has less to expand in the first place.
Rescue it now
Not fixable for the current bake; identify which of the three causes applies for next time
Prevent it next time
Preserve the rim untouched while opening the dough, use the hottest practical oven setup, and ferment long enough to build adequate gas
Related
Go deeper
Guides that treat this as an outcome to improve, an environment to work with, or a flavour to understand, rather than only a problem to fix.