Making homemade sourdough bread can be a finicky process, though so worth it once you finally grasp the steps and slice into a perfectly fermented loaf with a light texture and beautiful, even crumb. We have a whole list of tips for working with sourdough to help the process along, but even if you read them all, nurture your starter, and think you are doing everything right, you might still be using the wrong bowl to proof your dough in. This small error could be sabotaging your loaf before it even begins to bake.
A healthy, strong sourdough starter has a good ratio of yeast to lactic and acetic acids that helps raise bread. The acidity also maintains a healthy pH which gives the baked bread its tang and keeps harmful bacteria from growing in the starter. What does this have to do with bowls? The acidity in the dough can react with certain metals, like copper and aluminum, giving bread a metallic taste, so the only type of metal bowl you should proof your dough in is stainless steel. The same rule applies for breads made with dry yeast, although the reaction may not be as intense since it does not have the same amount of acidity as sourdough.
What other bowls can you use to proof dough?
Before you worry too much about whether your bowls are problematic, it’s likely that yours will be okay, because most metal bowls are now made with stainless steel, and due to its color, copper is pretty easy to identify and avoid. Stainless steel is actually a great choice for proofing dough because it’s durable, dishwasher safe, and retains the natural heat of the dough for a steady rise and strong ferment.
If you would rather avoid metal altogether, wood, plastic, and glass are all good options. Wood, like metal, is very durable and will help retain the temperature of the dough, making it a popular choice, but be sure it has a food-grade finish on it so that it’s safe for food preparation. Plastic is lightweight and easy to clean, but avoid ones that scratch easily so you don’t end up with flakes of plastic in your dough or rough up your hand when working with it. Glass always poses the risk of breaking, so it requires more care, but as long as there are no signs up chipping around the rim, it’s perfectly safe to use.
