More information on Gluten-Free Gums?

QUESTION:

Is there more information somewhere about how the cellulose and xanthan gums are sourced? Since both can be sourced from wheat, those gums can be a problem for people who are very sensitive to gluten or straight up allergic to wheat. I'd like to recommend this to a few friends and relatives, but I know several of them are not able to tolerate the gums, depending on how they were manufactured.

ANSWER:

Mehl’s Flour Company requires a letter of guarantee from every vendor that the ingredients we source are gluten-free.  We only buy from established ingredient companies, and every product we use is certified to meet moisture and protein levels, as well as other safety measures.  Every batch of flour, gums and starches we order is accompanied with a spec sheet showing all the test results for that batch.
 
Of the more than 60 separate ingredients we use commercially we have documentation on each one that it is gluten-free.