Subject: 41. Can I use metal utensils with sourdough?
A sourdough starter is acidic. Prolonged contact of your acidic starter with metal will discolor your metal utensil and dissolve tiny amount of the metal into the starter if you leave it for, say, weeks. So it is not a good idea to keep a sourdough starter in a metal container unless you want discolored, or given years of contact, damaged utensils. Your starter, or you, may not like the small amount of metal that is dissolved into the starter either.
So use a starter container made of a material that is not affected by acid. My personal preference are standard wide mouth glass quart canning jars, also known in North America as Mason jars. Mason jars are readily available and the wide mouth makes them easy to clean. Glass is highly acid resistant, very easy to clean and sterilize, which makes it a preferred material for starter storage.
In the short time of mixing and rising of sourdough bread, the effect of a slightly acidic mix is not noticeable on metal utensils, such as spoons and bowls. So there is simply no problem in using metal utensils, especially stainless steel utensils, to make sourdough bread.
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