I have read in many places that in order to calculate the gluten content of a given flour do the following. Find the weight of the protein content listed in the Nutritional Information. Then divide that weight by the weight of a single serving, which will be shown in the same list. As far as I can tell, this doesn’t work.
Take for example King Arthur All Purpose flour. KA’s specs tells us the content of protein in a single serving is 11.7%. https://www.kingarthurflour.com/shop/items/king-arthur-unbleached-all-purpose-flour-5-lb The nutritional information tells us that each serving is 30 grams and that there is 4 grams of protein per serving. https://www.kingarthurflour.com/shop-img/labels/1531942346035.pdf So, 3 divided by 30 = 13.3%. According to my calculations the accurate weight of the protein per serving should be 3.51 grams. I guess they round up. In any case it is useless for accurately indicating the percentage of protein in the flour.
Most flours don’t even show the protein content on their websites. Since the amount, and ideally the make up of the gluten is vital to artisan bakers, why isn’t this information readily available?
What is the real deal? The formula above is worthless to me.
Is it possible to take 3 servings (90g) and wash out the gluten. Then weigh the gluten and divide by 3?
Dan
Round numbers that is! Here a lot of flour whether it be all purpose or bread all have the same 4 g of protein per 30 g serving. And you are right that most manufacturers’ websites are useless.
You basically just have to buy a bag of flour, try it out and see if you like it. If not, kick it to the curb. ? I settled on the flour I use because it is unbleached, has no additives other than those mandated by the Canadian government, has 4 g of protein per 30 g serving, and I can buy it in 10 kg bags. I get tempted at times to try others but none of them meet my criteria.
"Is it possible to take 3 servings (90g) and wash out the gluten. Then weigh the gluten and divide by 3?"
Sort of... one makes a dough using 100g flour water, let the protein matrix form and bond well, then submerge working the dough in a bowl of water to remove the starch. What is left is gluten and any bonded proteins. Dry it and weigh it. That will give you the % of protein for 100g. Or go about it with 90g and divide the dry gluten by 3.
That will get you closer to what information you're looking for. Remember that not all protein in the flour is gluten. Take into account the amount of fibre listed. The higher the fibre, the more protein a flour will contain when compare to it's sifted counterpart. A whole flour can contain more protein but not more gluten.
Thanks, Mini. 100g flour makes it a little easier.
What do you think about the following? I am interested in a flour that is best suited for baguettes. Maybe the percentage of protein is not the most important number. Would the percentage of gluten paint a better picture?
Here is a video dealing with the subject that is interesting. https://youtu.be/zDEcvSc2UKA . I am thinking that usng this procedure to wash the dough would be best. In order to be sure everything else is washed away, you could check by throwing out the old water and replacing with clean water. Then try again to see if the water clouded up at all. Keep doing this until the water remains crystal clear. Ferrant with Puratos also has an excellent video on this.
I found some interesting information in THIS LINK. The following is an excerpt. “Gluten is poorly soluble in water, but the fraction known as ‘gliadin’ is soluble in aqueous alcohol.
Is it feasible to to extract gliadin useing the aqueoue alcohol? If so please explain how this is best done.
I’m pretty sure this is not realistic, but one can hope.
Dan
than to check for gluten on flour with labels I couldn't read. The bit with alcohol sounds like a waste of good alcohol. :) Your choice for baguette flour will depend on your recipe and yeast choice. I have yet to journey deeper into baggie territory. Sorry. But so far I like a mixture of AP and bread flour with a pinch of Einkorn or malt.
out of the 30 proteins found in bread flour only 2 make gluten. If you want the most gluten proteins buy white hard spring wheat grown in the Pacific Northwest. It's protein content total is a bit more but it is way higher in the 2 that count.
I am looking for a flour that is ideal for baguettes. I’m not sure about the ash content, but I think I need a weaker flour with less gluten. If I could find a wheat flour that was a little higher is gliadin would that help with the shaping?
Why can’t we get the full break down on our flours? Glutenin, gliadin, ash, protein, etc... Do commercial bakers get that type of detailed info?
Dan
10% low protein flour, the best one to use is actually the cheap store brand grocery store flour:-) In France it also might well have 2% fava bean or garbonzo bean flour in it that has no gluten at all as well.
If the protein is 11.7% it is 11.7%. Why do you need to do any other calculation? Or is is because the bag only gives protein per serving, rather than protein per 100 g?