Yes, high altitude affects sourdough baking. Reduce the amount of starter and water slightly, and shorten the proofing times.
At higher altitudes, the atmospheric pressure is lower, which affects the leavening process in sourdough. Dough rises faster because there's less pressure pushing down on it. This can lead to over-proofing and a collapsed structure. Additionally, liquids evaporate more quickly at higher altitudes, which can dry out the dough. Here's a breakdown of adjustments you can make:
Reduce Starter: Decrease the amount of starter you use by about 10-20%. This will slow down the fermentation process and prevent over-proofing.
Reduce Water: Lower the hydration of your dough by reducing the water content by 5-10%. This compensates for the faster evaporation rate.
Shorten Proofing Times: Monitor your dough closely and reduce both bulk fermentation and final proofing times. The dough will rise faster, so be prepared to shape and bake sooner.
Increase Oven Temperature: A slightly higher oven temperature (around 25°F or 15°C) can help set the crust faster before the dough over-proofs and collapses.
Strengthen Dough: Develop the gluten well through kneading or stretch and folds. A stronger gluten structure will better support the faster rise.
When baking at high altitude, consider using a slightly higher protein flour. The extra protein will help strengthen the gluten network and provide better structure to the dough, preventing it from collapsing during baking.