High-Gluten Flour, and the Role of Gluten in Bread Structure

[chef koo]

So I was watching an episode of "Good Eats", and Alton was saying something about gluten, saying that if you over work it, the gluten disintegrates. Is this true? And if so can anyone elaborate on what that means? Does it mean that if I knead a dough long enough, it won't hold it's shape?

[jackal10]

You can overwork gluten in a high speed mixer, such as a food processor.

Its very hard to impossible to do so by hand.

Left alone it recovers.

[scott123]

Kneading develops gluten, but, if kneaded excessively, kneading will break gluten down. As gluten breaks down, it will release trapped water, the dough will go slack and lose it's ability to keep it's shape. The torn gluten will result in a wet, lumpy dough, that, if baked, will have minimal volume. Damaged gluten is the kiss of death for great bread.

The protein content of a flour, though, greatly impacts it's kneading durability. Stronger bread flours will break down far slower than weaker flours. Hydration also plays a role. When kneaded, wetter doughs stress the gluten less, resulting in slower gluten development at the start and slower gluten fragmentation as time passes. For instance, a 75% hydration 14% protein flour dough can easily handle 20 minutes of aggressive kneading without showing much signs of wear, while a 10% protein all purpose flour with 55% water will be pretty much be trashed in the same time.

Just because strong bread flours break down slowly, though, doesn't mean that you want to knead them without care. Their water holding ability will peak in as little as 10 minutes of kneading. Once you've reached peak absorption, further kneading is only detrimental to final loaf volume and oven spring. If you're cold fermenting (recommended), which is a kneading equivalent in itself, you'll want to dial back that initial kneading time dramatically. This is why no knead breads are so successful at achieving great volume.

Edited November 29, 2010 by scott123 (log)

[chef koo]

Wow. Didn't realize. Dumb question but if you were to bake a pastry crust of some sort, like a sweet dough, if you kneaded it forever and broke down the gluten of the flour, would it be really tender and not shrink at all? And this isn't necesarily for pastry but I've seen machines kneade pasta for hours. Does the same idea still apply?

[scott123]

Well, hydration and protein content play the largest role in gluten durability (imo), but fat's a fairly major player as well. Fat coats the protein molecules and prevents them from bonding, which, in turn mitigates gluten development. With a very high fat pastry dough, it might not even be possible to knead it long enough to inflict any palpable damage on the gluten. It's far better to use very weak pastry flour and methods that prevent gluten from forming in the first place (ice water, minimal handling, rests).

[glennbech]

I am experimenting with adding pure gluten powder to my doughs, to be able to use higher percentages of whole-grains.

The recipe of the day is ;

Poolish

300g (100%) Whole Grain Wheat

330g (110%) Water

5g dry yeast

Dough

600g Poolish

400g Whole Grain finely ground wheat flour

300g White "AP" wheat flour

310g Water

60g Pure gluten powder

30g Olive Oil

20g salt

This gives 70% whole grain loaves. (64% water bp.)The "plan" is that the gluten will counter the "compactness" one usually gets with such high levels of whole grain. I am experimenting with shortening and fats to counter the "spongyness" the gluten can give.

Have anyone else tried this, any thoughts?

Edited August 10, 2012 by glennbech (log)

[Panaderia Canadiense]

With that much whole grain, you might want to investigate sourdough leavening in place of the poolish. It's a little slower but you get a great rise from it, and it works beautifully with whole wheat and other high-bran grains without having to add much by way of extra gluten.....

[helloicedcoffee]

Agreed. I'll use vital wheat gluten when necessary but it very rarely mixes in completely and becomes sticky almost immediately - I bake a lot with spelt and find that it isn't really worth the trouble. I also think there's a mouthfeel issue to breads made with it as well. A sourdough starter would be a great place to start; or perhaps focus on how rich and moist those denser breads can be by adding nut soakers (I really like hempseed for this).

Are you thinking that butter would leaven the dough in the oven from evaporation like it would in a croissant or pastry? Seems counter intuitive to add fat to a dough full of whole grains!

[HungryC]

Agree with above posters....go sourdough, leave out the fat, and you won't need the added gluten. Your proportion of whole grain to white flour (600g total to 400g) isn't so terribly high.