It took me many years of baking with sourdough to believe that I really needed to discard starter before feeding it. I couldn’t bear to throw any away, and couldn’t understand why I needed to. The whole process seemed wasteful. Trust me: if you are going to keep extra starter on hand, you need to discard a portion before feeding it.
Starter, to be well nourished, needs a precise ratio of new flour to existing starter. If you begin the feeding with too much starter, you will waste huge volumes of flour in an effort to preserve this ratio. Or, you will not preserve the ratio and, over time, you will have a weakened starter. So, in an ironic twist, throwing starter away actually saves you flour.
When I discard starter, I like to transfer the portion I’m tossing into another jar, rather than into the sink or compost bucket, for two reasons. First, it eliminates the possibility of mistakenly pouring out all of the starter. Second, it leaves me with a backup jar of starter in case anything happens to the first. (I’m always afraid my jar of starter will drop and break, leaving me with nothing to show for my years of devotion.) I ultimately discard the back-up starter when I have more starter to add to the back-up jar, but by then it is less vital and easier to part with.
Copyright 2014, Ellen Arian, Ellen’s Food & Soul