Question: Building my SFO Sourdough Starter

I'm busy activating my SFO sourdough starter.  I'm at the point where I am feeding two jars and the directions say to throw away all but 1 cup of the mixture every 12 hours.  Can I use the throw away parts to make a loaf?

Toast

Use it along with yeast as a flavor component (pre-ferment). Add a little flour, if needed, to adjust it to the consistency of your final dough.

Jim