Can I use some of the old Boule in new dough? Thought perhaps this would enrich the flavor.
in new bread is called 'altus' It enriches the flavor and improves the crumb /chew. Just get it wet and crumble into the dough like bread crumbs. Really great for high % rye breads and pumpernickel but it works well for any kind of bread.
Search for altus on this site for way more info.