The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Does protein content = gluten content?

obrien1984's picture

Does protein content = gluten content?

All-knowning Internet,

I've had it in my head for a long time that protein content = gluten content (rather, the potential to produce gluten from kneading). Is that a correct assumption?

SteveB's picture

While glutenin and gliadin, the proteins that combine to produce gluten, are the two major proteins in wheat, there are other proteins present, albeit in lower quantities.  Therefore, strictly speaking, protein content does not necessarily equate to gluten content.


Chuck's picture

My understanding is that while measuring "protein" in a lab is fairly easy, measuring "gluten" is difficult. Thus most of the numbers you'll find are actually for "protein" content. The commercial wheat grown in north america has been selected over centuries (call it "natural genetic modification" if you want to:-) so most of the protein in the endosperm is in fact gluten. As a result, when talking about north american white flours, you can use the more easily available protein numbers as very good substitutes for gluten content.

Note though this practical near-equivalence of protein and gluten is not true for "whole" flour or for other kinds of grain besides wheat or in some other parts of the world. For just one example, quinoa is very high in protein yet none of it whatsoever is gluten.


(At least that's my understanding of the situation. I'm counting on somebody [steveb?] to correct me if I'm talking through my hat:-)

ananda's picture

Chuck's just about got the important qualifiers here.   Wholegrain flours contain proteins from the outer parts of the grain which have no gluten-forming potential.

The "selection" process  discussed is interesting, but is equally applied in Europe too.   Perhaps more important is climate, with short, hot and dry Summers following cold Winters producing the types of strong flour clearly being alluded to.

One grain not mentioned here, but well worth illustrating is durum wheat.   A hard grain with a high protein reading.   But not considered "strong" in terms of potential gluten-forming protein.   Spelt too has high protein, but low gluten content.

Best wishes