Hi there,
I have been making sourdough for quite a while now and have had some spectacular results, but recently things just have not been working out and I cannot figure out why.
I'm generally using the Tartine basic country loaf recipe which has worked great before.
Starter: 200g 50:50 white:whole wheat, 100% hydration (though I have used others)
Recipe: 900g white (Fairhaven Mill, 10% protein) + 100g King Arthur Organic whole wheat, hydration: 75 - 80%, 15g salt.
I normally use a 5 - 20% inoculation of starter and use it when a teaspoon of it is just able to float in water. I generally mix the dough then leave for 30 mins before adding the salt with a little extra water. Then I stretch and fold about once every 30 - 40 mins for 2 - 4 hours, after which I divide in two. I do an initial shaping and bench rest for 30 mins then final shape and put in a proofing again for between 2 and 4 hours or longer in the fridge. I try to use the poke test on the dough to get an idea of whether it's ready or not. I bake in a cast iron pan or some improvised equivalent, but the problem seems to occur before the bake.
I feel like I have tried systematically varying a ton of stuff to no avail: using a more or less mature starter, shortening and lengthening the time taken for each stage, reducing and increasing the amount of manipulation, different starters, refrigerating, more or less shaping...
Problems range from totally collapsing, losing shape, or splitting into regions of very large holes surrounded by dense crumb.
Any thoughts would be welcome!