What is actually happening between my levain and my dough?
Hi all,
I've been using spelt flours (whole and white) and a whole rye starter (mainly at 100%) for nearly my whole sourdough adventure (6+ months and over 150 loaves). I typically like to think about baking from a chemistry perspective, and thought I had a fair understanding of the variables at play here (e.g. gluten quality, temperature, available starches for yeast consumption, etc.) Until I posted regarding tearing of my dough during the bulk fermentation. A lovely user suggested that my starter was too mature, and therefore the acid load too high: implying that the acid was eating away at the dough integrity.
This leads me to a bunch of questions (that some cursory googling failed to answer):
1. Does lactic (acetic) acid denature gluten/degrade dough "integrity" (elasticity and extensibility)? If so, do the quantities we see from a typical amount of starter (20-30% flour weight) have a practical effect on the gluten?
2. Which would have a higher acidic load: dough left to autolyse for 4 hours with 2-hour old, young levain mixed in OR dough left to autolyse for 4 hours with a 6-hour old levain mixed in after the autolyse?
I'm trying to update my mental model of what's going on in my dough and using the Trevor Wilson analogy, I'm thinking about my dough as a brick wall: gas plays the role of the bricks and gluten the mortar.
Given this analogy and I'm wondering why we all don't something like the following:
• set-up an overnight autolyse
• next morning, make your levain
• once the levain is at its peak, mix it into your dough
• process your dough (stretch and fold, slap and fold, knead, whatever) as usual
Or at the very least, start an autolyse as the same time as your levain build. In this way, we can insure that our gluten is nice and ready to trap any and all our levain's exhaust...
I know this is something of a long-winded post but I'm looking to hear other people's thoughts about how they structure they're fermentation and why...
Thanks in advance!
Really good info in there and there is even a paragraph supporting my guess of too much acid load degrading the dough.
http://www.sfbi.com/pdfs/NewsF04a.pdf
Great article Danni.
I still don’t understand how acid from the levain is supposed to increase the strength of the dough. But I read near the end of the article the too much acid will cause the gluten to break down. I wished someone (maybe Doc Dough) would come up with an experiment to show that acid strengthens dough.
Dan
Thanks for that link. I guess when it comes to my rye starter + this organic white spelt, the tolerance for acid is lower than I'm used to. It's really cool to read that pre-ferment (and therefore starter) strengthen dough. Interestingly, I just ran a (tangential) experiment on whether there's a tangible difference in the resulting loaf if one does a "pure autolyse" (just water & flour) versus a "kitchen sink" (water, flour, salt, oil, sugar, etc.)... To my tastebuds and eyes, the differences are within a reasonable statistical margin (the loaves tasted basically the same).
The big difference was in the feel of the dough, tbh: the pure autolyse dough FELT GREAT. IT was much more elastic than the dough which had oil, sugar and salt incorporated during the autolyse...