Tin vs dutch oven - temperature and time
I tend to work with 2-loaf batches. I can fit one dutch oven and one tin in my oven so that's what I do. I use a Pyrex dish upturned on the tin to hold steam for the first 20 mins (and the lid on the DO of course).
Generally the tin loaf gets a darker crust (all over) than the DO boule. My home oven is fan forced.
Today I baked at work in an oven with no fan, and bottom heat under the floor of the oven. The boule came out great, lovely and burnished overall, the base slightly overdone. But the tin loaf, it's burnt. Very dark brown/black. Will probably have to cut the worst bits off. I took both out after 45 mins, based on what I was seeing on the boule.
So my question is, do tin loaves usually need lower temperatures? Or shorter bakes? Could I bake them together but take the tin out after 30 mins? Maybe a bit cooler then crank it when the tin is out?
Details in case they matter. Tartine country loaf recipe. 10.5 hour refrigerator proof. Oven cranked to 270C, as my last attempt on this oven, of a boule only, at 250C, would not burnish properly even after 50 minutes. (I forgot to bring an oven thermometer, both times) Also, my dutch oven is a heavy base stainless steel type. The tin, I don't know the brand as I inherited it. It seems to be double-walled.
Probably just talking to myself but I had an idea about this after all my roast vegies were burnt on the bottom by the same oven yesterday.
The dutch oven is bare stainless steel. The loaf tin is black. Especially without a fan, a lot of the heat transfer will be radiative and the black will absorb it much more readily. Maybe if I take the tin out earlier, then crank it, and/or wrap the loaf tin in tin foil, it will help.
Heat conduction. The material itself could be the cause. If your DO is stainless steel, it’s conductivity rating is 7-26, while tin is 36-39. So there is the potential for exactly what you experienced.