Matt sent me this problem. Baking Nina’s Simple Danish Rye he sometimes gets a gummy bottom like this:
Further more, he says sometimes, when he bakes two loaves, one is gummy the other is fine.
He gives the dough 45 mins bulk fermentation in the mixing bowl + 2-3 hours proving in the tin. Then bakes for 50 mins + 15 mins removed from the tin.
When Nina first sent ne the recipe she said: Bake 1hr @ 110C & 1hr @ 180C, Or 1.5-1.75hrs @175C – cover with foil if burning. Turn off oven, remove from tins and return to oven 20-30 mins.
Anyone have any suggestions? I don’t pretend to know what’s going on. I thought impacted bottoms was a sign of underproving, but why one tin and not the other? I assume they are baked in Matt’s cob oven. Are there cold spots? The crumb is fairly irregular. I wondered if your starter was well mature when the dough was mixed – not that that would explain the discrepancy between the two loaves.
Help Matt sort his bottom.
The PArtisan Baker 
Are both tins of the same metal and design? Is one loaf really completely fine when the other one is stricken with ‘gummy bottom’? One tin baked lower in the oven than t’other? Heat not circulating properly around the one that has ‘gummy bum’?
Like Mick, I’m more thinking out loud than actually sure what this might be…
I bake a batch of 100 percent Rye most weeks for a family that has banned Wheat from their house. The batch consists of 4 – 5 loaves. I have never had this problem. My problem was that they kept sticking in the tins. I changed to disposable silicon loaf pans and the paper just stuck to the bread. Now I have gone back to metal pans and just liberally coat the tins with oil and oats.
Hi, thanks for posting this Mick. I’m mindful that the first thing I need to straighten out is baking times – my memory (and notebook) was obviously hazy after B5. I’m doing the 175ºC option so will extend the baking time.
(Though the loaves to date have gone down without anyone, including me, wondering that they were under baked – maybe my fan oven is helping).
I’m using two new identical tins and for these am baking in the kitchen fan oven, on the same shelf.
Just a pot-shot idea really, but there’s no chance that this could be caused by excessive oil from oiling the tin pooling in the bottom and soaking into the dough as it bakes?
Thanks,
Matt