When is a starter ready for use? Substitute for red rye malt in Borodinsky
I took a batard of Norwich Sourdough to an potluck recently and was told by new Uzbekistani friends there that the taste of the bread was the closest they've had to that of home they've had since moving to Canada. Long story short: they are joining me in the next few days to bake Norwich SD and will then go home with their own starter. I'm compiling a primer for them and would appreciate tips on how to describe a starter that is ready for use.
The reason I pose this question is because I've left off waiting for my starter to double or bubble acitively. I simply KNOW it's ready after the nine months or so that I've been baking. Gut instinct is not a good tool to with which to teach.
The Uzbekistanis are keen to start baking Borodinsky bread as well, something I've yet to try although this site certainly has enough information available for me to do so sometime. Is there an acceptable substitute for red rye malt