(This was first posted in the ‘home sourdough’ section of the forum on 3rd June.)
This is the first in what I hope will turn out to be a series of experiments with a basic recipe. (Apart from anything else I am going to use this to work towards better sourdough baguettes).
With any of these experiments it would be great if some other folk were interested in replicating the experiment in order to make the results more robust. You don’t have to follow my recipe exactly, but it is important the the only difference between the two doughs is the variable that we are interested in (in this case starter hydration). [In order to avoid differences in proving, put the second dough in the fridge while baking the first, unless you can bake two at once].
I posted a recipe for Pane Francese  a while ago, with two variations - one using a firm starter (at 64% hydration), and the other using my standard 100% hydration starter.
It seems like the former is fairly common in french sourdough recipes, but I wondered if it made any difference whether you used a firm ‘dough’-like starter, or one more like a batter. (I know that Bill usually uses an even more watery version at ~166%). So I have put the two head to head.
To determine if differences in starter hydration make any difference to the rising behaviour or end texture of loaves in a simple white sourdough recipe
I followed the recipe more or less to the letter. I refreshed my standard starter (at 100%) for 12 hours, and then added 30g of this to two different jars. To one I added 50g water and 100g flour, to the other I added 75g each of flour and water.
They were left for 12 hours at room temp (15-20C)
The amount of water in the actual recipe was reduced in the ‘100%’ version so that the overall hydration of the dough would be equivalent. (350g in the 64% recipe, 320g in the ‘100% recipe’)
Proved for four hours with turns every hour. I wondered if the 64% had slightly more activity, with more bubbles evident on slashing the dough, but there was little difference between the two.
The doughs were shaped, and wrapped in a tea towel, and left to prove. [I did something that I haven’t previously done, which was to leave them to prove overnight out on the balcony. I hoped that the cool temperature (but warmer than the fridge) would let them prove without me having to get them out of the fridge in the middle of the night. Last night was quite a mild night for Melbourne - 14C at midnight, dropping to 10C by 5am).
Left for 7 hours or so, then put in the fridge while the oven warmed up.
The one on the left was the 64% starter.
Not much to tell between the two. I thought that the 100% loaf had slightly better oven spring, but not much to tell.
I had to go to work, so left my faithful assistant to document and dissect the loaves. It looks as though the 100% loaf had a slightly better texture, but I think I am going to have to go home and interrogate the loaves a bit more to be sure.
Not much discernible difference using a firm starter or a more liquid starter. Possibly more open texture with the liquid starter.
I wonder whether differences would be more marked between 64% and 166% starter? Another experiment to do perhaps…