Ash content in white whiole wheat?

usually indicates from where on the wheat berry the flour was milled.  Higher ash content in true white flours indicates that it was milled from the part of the endosperm closer to the outside of the berry.

Accordingly, true whole wheat flours tend to have very high ash content, reflecting the entirety of the berry.

Ash content is used along with protein content to judge the quality of the protein as the protein content of the outer part of the endosperm is higher numerically, but lower in quality.  Thus, at the same protein percent, the flour with the higher ash content will have lower protein quality.  Again, this is moot in true whole wheat flours, as the entire berry is milled.

There is some variation in how what is marketed as whole wheat flours are milled and this might impact ash content.  However, one would not expect white whole wheat to have a significantly different ash content as the difference between white and red wheat is the pigments in the wheat - not the mineral content.

However, if you really want to know, you might call the flour source.  If you are really intent and they cannot give you an answer, you can send samples to CII laboratories (just type it into your favorite search engine) - and for a reasonable fee find out for yourself.  They are moving this week, but usually can turn around samples pretty fast. (No, I don't work for them - I have had some analysis done on my home milled flour, so they send me updates...)

Hope this helps.

I am looking for a high-ash content flour to use in one of my formulas.  Does anyone use this kind of flour, and if so, do you have any favorites?