Is it true that sourdough fermentation alters other things but not gluten? My understanding is that the acidity of sourdough degrades gluten. I know of one person who was actually a (semi-?)professional baker before developing—at least by her account of things—a gluten intolerance, who found that she could eat some sourdough things whose non-sourdough things made her feel bad. But of course I have no way of knowing whether it was really the gluten that was giving her problems.
(Who adds flour to the dough after a sourdough fermentation? Other than maybe a dusting to prevent sticking while shaping or proofing, which will add little enough that I’d have thought someone who isn’t outright coeliac should be OK with it.)
The normal sourdough recipe is to take some of the starter, mix it with more flour and water, and let it rise/ferment for only 1-2 hours before baking.
That looks like no sourdough recipe I’ve ever seen. The usual process goes like this:
If your starter isn’t being fed very frequently, take some and give it a couple of feeds at reasonably short intervals.
Now take some starter, combine with flour and water, and leave it until it’s active and bubbly—might be 4-12 hours depending on the starter:flour ratio, starter activity, ambient temperature, etc.
Combine with flour, water and salt.
Bulk ferment: Over the next 4-12 hours, depending on the starter:flour ratio, starter activity, ambient temperature, etc., strengthen the dough by some combination of kneading and gentler folding. (A typical prescription might be: (wait 30 minutes, do some folds) 6 times, then leave it alone until it’s increased sufficiently in size, which might be another ~2 hours.
Shape and transfer to a proving basket.
Prove: Leave it for maybe 1-3 hours (or substantially longer in the fridge) until it’s increased in size again, passes the “poke test”, etc.
Bake.
There are various wrinkles (e.g., you might combine just flour and water some way in advance, before combining with starter and salt; this allows a process called autolysis) but that’s the general technique. Maybe if you do it in warm enough conditions and with a very active starter you might get it down to 4 hours bulk fermentation + 1 hour proving. You absolutely cannot do it in 1-2 hours.
(You can do a distinctly not-normal thing that’s much quicker. If you keep the bits of sourdough starter discarded at feeding in a bowl or jar in the fridge, then once you have ~1kg of that you can add a bit of flour, mix it up a bit, leave it a couple of hours, and bake it in a loaf tin. You can make a rather nice loaf this way, especially if you like your sourdough breads dense and sour. But it’s not by any stretch of the imagination “the normal sourdough recipe”.)
Just in case I’d somehow been living in a weird sourdough bubble, I put “sourdough recipe” into Google and looked at the first 8 hits. First: a no-knead no-fold recipe. 8-14 hours bulk fermentation + 1 hour refrigerated proving. Second: 3 hours bulk fermentation + 4-8 hours proving. Third: 3-12 hours bulk fermentation + 1/2-1 hour proving. Fourth: 3.5-7.5 hours bulk fermentation + 3-4 hours proving. Fifth: 2.5-3 hours bulk fermentation + 2.5 hours proving. Sixth: 4.5 hours bulk fermentation + overnight proving. Seventh: 4.5 hours bulk fermentation + overnight proving. Eighth: 10-12 hours bulk fermentation + 1.5-48 hours proving.
ok, ferment does degrade gluten but very slowly. Once the levels of lactic acid build up sufficiently, then the acid hits the gluten, but that is rather longer than 12hour. If the gluten is destroyed, then so is your dough structure—it loses the ability to trap air and steam. People struggling with ordinary bread but able to eat sourdough I think is rather common. Based on Monash publications, I would say the highly fermentable fructans in wheat are converted to easier to digest forms (mannitols??). Pretty testable for an individual. If you struggle with high fructan foods (wheat, onions, garlic) but happy with high mannitol foods, (sweet potatoes, mushrooms, melon), then I would predict you will be ok with sourdough (assuming my memory of what fructans convert to during ferment is correct). Sourdoughs with lots of low fructan flours such as oat and spelt should be even better.
As to adding flour later, then I was told by a baker that what is sold as white-flour sourdough breads can be made commercially by taking starter, maybe added to flour/water and partly fermented, but then add bakers yeast and rest of flour and process from there “normally”. The process is much faster, more mechanised and, importantly, predictable—ie cheaper. The ferment still gives a sourdough “tang” to the product to keep customer happy.
My son went to a bakery in a holiday town to get sourdough loaf for his IBS sister and quizzed baker on their process to ensure he was getting real thing. She offered him a job immediately (not that he wanted one).
You can lose some gluten and still have enough to maintain the structure of your dough. I think the person I mentioned thinks that’s what’s going on. (But it sure seems plausible to me that the actually relevant difference between sourdough bread and other bread is something else. If gluten degradation were the mechanism then you’d think you could do equally well by using weaker flour, not kneading as much, etc.)
I’ve made breads that are actually leavened with ordinary baker’s yeast but also contain some sourdough starter (in fact I have two loaves made that way sitting cooling on a rack right now), but it would never occur to me to call them sourdough breads. They’re ordinary yeasted breads with a bit of sourdough starter in to give flavour and longevity. But I guess if you’re selling bread, and your customers like the idea of sourdough bread, and you aren’t too scrupulous… :-)
If you google “what can legally be called a sourdough bread”, then I think you might see that this can be a problem.
But anyway, I think we can safely say that sourdough is probably a good way to test whether the issues are really gluten sensitivity, (because it certainly has some), or with other components of wheat.
Is it true that sourdough fermentation alters other things but not gluten? My understanding is that the acidity of sourdough degrades gluten. I know of one person who was actually a (semi-?)professional baker before developing—at least by her account of things—a gluten intolerance, who found that she could eat some sourdough things whose non-sourdough things made her feel bad. But of course I have no way of knowing whether it was really the gluten that was giving her problems.
(Who adds flour to the dough after a sourdough fermentation? Other than maybe a dusting to prevent sticking while shaping or proofing, which will add little enough that I’d have thought someone who isn’t outright coeliac should be OK with it.)
The normal sourdough recipe is to take some of the starter, mix it with more flour and water, and let it rise/ferment for only 1-2 hours before baking.
That looks like no sourdough recipe I’ve ever seen. The usual process goes like this:
If your starter isn’t being fed very frequently, take some and give it a couple of feeds at reasonably short intervals.
Now take some starter, combine with flour and water, and leave it until it’s active and bubbly—might be 4-12 hours depending on the starter:flour ratio, starter activity, ambient temperature, etc.
Combine with flour, water and salt.
Bulk ferment: Over the next 4-12 hours, depending on the starter:flour ratio, starter activity, ambient temperature, etc., strengthen the dough by some combination of kneading and gentler folding. (A typical prescription might be: (wait 30 minutes, do some folds) 6 times, then leave it alone until it’s increased sufficiently in size, which might be another ~2 hours.
Shape and transfer to a proving basket.
Prove: Leave it for maybe 1-3 hours (or substantially longer in the fridge) until it’s increased in size again, passes the “poke test”, etc.
Bake.
There are various wrinkles (e.g., you might combine just flour and water some way in advance, before combining with starter and salt; this allows a process called autolysis) but that’s the general technique. Maybe if you do it in warm enough conditions and with a very active starter you might get it down to 4 hours bulk fermentation + 1 hour proving. You absolutely cannot do it in 1-2 hours.
(You can do a distinctly not-normal thing that’s much quicker. If you keep the bits of sourdough starter discarded at feeding in a bowl or jar in the fridge, then once you have ~1kg of that you can add a bit of flour, mix it up a bit, leave it a couple of hours, and bake it in a loaf tin. You can make a rather nice loaf this way, especially if you like your sourdough breads dense and sour. But it’s not by any stretch of the imagination “the normal sourdough recipe”.)
Just in case I’d somehow been living in a weird sourdough bubble, I put “sourdough recipe” into Google and looked at the first 8 hits. First: a no-knead no-fold recipe. 8-14 hours bulk fermentation + 1 hour refrigerated proving. Second: 3 hours bulk fermentation + 4-8 hours proving. Third: 3-12 hours bulk fermentation + 1/2-1 hour proving. Fourth: 3.5-7.5 hours bulk fermentation + 3-4 hours proving. Fifth: 2.5-3 hours bulk fermentation + 2.5 hours proving. Sixth: 4.5 hours bulk fermentation + overnight proving. Seventh: 4.5 hours bulk fermentation + overnight proving. Eighth: 10-12 hours bulk fermentation + 1.5-48 hours proving.
ok, ferment does degrade gluten but very slowly. Once the levels of lactic acid build up sufficiently, then the acid hits the gluten, but that is rather longer than 12hour. If the gluten is destroyed, then so is your dough structure—it loses the ability to trap air and steam. People struggling with ordinary bread but able to eat sourdough I think is rather common. Based on Monash publications, I would say the highly fermentable fructans in wheat are converted to easier to digest forms (mannitols??). Pretty testable for an individual. If you struggle with high fructan foods (wheat, onions, garlic) but happy with high mannitol foods, (sweet potatoes, mushrooms, melon), then I would predict you will be ok with sourdough (assuming my memory of what fructans convert to during ferment is correct). Sourdoughs with lots of low fructan flours such as oat and spelt should be even better.
As to adding flour later, then I was told by a baker that what is sold as white-flour sourdough breads can be made commercially by taking starter, maybe added to flour/water and partly fermented, but then add bakers yeast and rest of flour and process from there “normally”. The process is much faster, more mechanised and, importantly, predictable—ie cheaper. The ferment still gives a sourdough “tang” to the product to keep customer happy.
My son went to a bakery in a holiday town to get sourdough loaf for his IBS sister and quizzed baker on their process to ensure he was getting real thing. She offered him a job immediately (not that he wanted one).
You can lose some gluten and still have enough to maintain the structure of your dough. I think the person I mentioned thinks that’s what’s going on. (But it sure seems plausible to me that the actually relevant difference between sourdough bread and other bread is something else. If gluten degradation were the mechanism then you’d think you could do equally well by using weaker flour, not kneading as much, etc.)
I’ve made breads that are actually leavened with ordinary baker’s yeast but also contain some sourdough starter (in fact I have two loaves made that way sitting cooling on a rack right now), but it would never occur to me to call them sourdough breads. They’re ordinary yeasted breads with a bit of sourdough starter in to give flavour and longevity. But I guess if you’re selling bread, and your customers like the idea of sourdough bread, and you aren’t too scrupulous… :-)
If you google “what can legally be called a sourdough bread”, then I think you might see that this can be a problem.
But anyway, I think we can safely say that sourdough is probably a good way to test whether the issues are really gluten sensitivity, (because it certainly has some), or with other components of wheat.
Also, see https://en.wikipedia.org/wiki/Chorleywood_bread_process. This is surely producing a bread with a rather different chemistry to more traditional processes.