Tartine basic country bread with room temp bulk fermentation

Ideally I'd like to have a nice bread that I mix the dough for in the evening, bulk ferment it overnight on the counter and finish by shaping, proofing and baking in the morning. To get there I started experimenting yesterday with the Basic Country bread from Tartine and modifying the schedule and levain % to extend the bulk fermentation.

While at it I mixed two batches of dough, each with different %s of levain, one at 6% and one at 10%. Room temperature started at about 18C/64F in the early morning, to about 68F later in the morning and for the remainder of the day and evening.

• 22:10 mixed 25 grams of starter (100% hydration) with 125 grams of starter mix (40% WW, 10% rye and 50% Italian tipo 2) with 125 grams of water (18C/65F) and let rise overnight
• 08:50 the levain has little over doubled in volume and I'm starting the autolyse on the two batches of dough, both 450 white (tipo 0), 50 grams whole wheat, 350 water @ 11C/52F (no levain added, as I'd like to postpone the fermentation for as long as possible)
• 09:30 mixing two final doughs with the levain (60 grams on one of them, 100 grams on the other), salt (10 grams each batch) and a last bit of water (50 grams @ 52F). This brings dough hydration to 73% and 75% respectively. Bulk fermentation starts with DT of 64F and volume is about 1 liter.
• 10:05 stretch and fold
• 10:35 stretch and fold
• 11:05 stretch and fold. DT is now 66F. The two doughs are still very much alike
• 11:35 stretch and fold
• 13:50 DT is now 68F (which is also the ambient temp). Dough in first batch (the one with more starter) seemed to have risen a tiny bit more than the second batch and more airpockets seem to have developed in the first batch. Volume has still not increased a lot though. Maybe now that temp has gone up to 68F things will speed up a bit.
• 14:55 The difference between the first and the second batch is now clearly visible. The first has risen slightly more and there are definitely more and bigger airpockets in the dough. Also the surface is showing more signs of bubbling in the blue (first) batch than in the second. Now leaving for a few hours, probably coming back at around 6'ish.
• 21:50 Just came back. Wasn't supposed to stay out this long but friends invited us over for dinner and I had some trouble parking the car. Volume has increased on both doughs, to about 1.4 liters in the first and 1.6 or 1.7 liters in the second. Not sure when bulk fermentation is finished. Poke test has the doughs both spring back, but not really fast. It's been almost 12 hours now. Decided to start dividing and shaping. DT is still 68F. Starting with a pre-shape. Dough feels elastic, not feeling a real difference between the two batches. Doing a bench rest
• 22:20 After a 30 minute bench rest doing the final shape now. Not noticing a huge difference between the loaves so far
• 22:30 Retarding the boules in bannetons the fridge (42F) for the night. Wouldn't normally do this, but don't want to stay up all night ;-)
• 09:00 Taking the first batch from the fridge and letting them proof a bit more while heating the oven at 245C/475F
• 09:45 - 12:30 Baking the loaves in a Dutch oven (22 lid on & 10m lid off) with a 5 minute reheat in between to get the oven back up to 245C/475F

I was hoping and actually expecting to see a lot of differences between the two batches of dough having different levain percentages, but there wasn't any really... Taste, crumb, crust, looks, they're all the same. Taste was wonderful by the way. Not overly sour, just great!

So in short, by modifying the levain percentages I was able to extend the bulk fermentation to about 12 hours.

Bulk fermentation of the dough with 10% levain.

Bulk fermentation on the second dough (lower levain %). You can clearly see the difference.

Crumb looks great IMO. Crust in some places a bit bold, but that's probably due to my not lowering the temp after removing the lid of the DO. Scoring is still not very good, I have to get myself a lame.

Any comments / recommendations?

cheers,

Alef