Re: How can you extract gluten from flour to measure content?

The material that is washed down the drain is more than likely not gluten.
Wheat flour is made up of 12 % protein, 80 % carbohydrate, 2 % lipid and
the remaining 6% as ash and water. For example, if you use 100 grams of
flour to conduct your gluten experiment, one would expect that 12 grams (or
12 %) of the material would remain as proteins.  

Wheat protein is made up of four general proteins; albumins, globulins,
glutenin, and gliadin.  Albumins and globulins are water soluble thus would
wash out during the "running under the water" step. Glutenin and Gliadin
are the two proteins that make up Gluten. These two proteins are not water
soluble thus would not be washed down the drain by cold running water. 
  
Since Glutenin and Gliadin make up about 80 % of the wheat proteins, one
would expect that if 12 grams of protein were in the 100 grams of flour
than 80 % of the 12 grams or 9.6 grams (12 grams X .80) would be the amount
of gluten remaining after the washing step. 


Hope that helps.