I have made Chad Robertson's Tartine bread several times with mostly good results. The past few times however, it seem the preferment takes much longer than overnight (to pass the float test). I prepare the preferement exactly according to Chad Robertsons instruction then leave overnight. In the morning, the preferement just sinks in the float test, I place it in a warmer area and then try again and hour or two later only to get the same results. Even more hours later I finally get it to pass the float test, but by this time it is up to 15 to 18 hours later than started, much longer than "overnight" as indicated in the Tartine book.
Is this normal? Should the preferment process take longer than the book states?
Doesn't his "master" recipe call for a refresh after the overnight? I believe that you take a spoonful of the overnighted leaven and add your flour and water and let it process for 4-6 hours after that.
I found today that my leaven floated very nicely at four hours.
I looked it iup and the only extension for the preferment process is in case it smells to vinegary after overtnight fermentation. Othewise, a sweet smelling preferement should work fine. So far I have never had to extend my preferement.
Thanks for the input.