I'm following this recipe http://weightloss-slim.fit/node/32420/durum-bread%3C/a%3E%3C/p%3E%3Cp%3EDurum Bread by Hamelman with a Biga and Sourdough Starter.
If I were to retard this dough do you advise...
1. At the end of the bulk ferment and before shaping (stages 5-6)?
Funnily enough I'm more in tune with sourdough but with the added yeast in the Biga I'm not sure.
You could always leave out the yeast and treat it as straight sourdough. I made his semolina with corn, millet and semolina soaker last week. It rose more slowly than my usual bread so after an overnight bulk retard in the fridge I had to leave it on the counter for a couple of hours before shaping and final proof. I got good oven-spring and it was delicious bread.
I find bulk retard easier because high hydration doughs are firmer and easier to shape when they are cold.
After reading your comment I re-read the recipe and noticed there was added yeast in the final dough. Didn't notice that before. I chose to leave it out. Not sure if including the biga still makes it a hybrid as I think it's pretty much spent and added for flavour but it's now a sourdough with an added biga.
Another thing I did was lower the hydration a tad. Will have to work out what the final hydration was. The dough was still quite wet but was good to handle. Wet hands so it doesn't stick but a dry bench to get that drag. Doing a pinch and fold in the bowl and when a boule is formed turning it out onto the bench just to tighten up I find works well for a wet dough.
It's now in the fridge.
P.s. 72% hydration