For various reasons, I believe the CFR defines flour as a food, not a food addit...

For various reasons, I believe the CFR defines flour as a food, not a food additive, but it may have additives that qualify. (I can't find any text that explicitly states that foods are not food additives, but either way, no form of wheat flour is listed in the Substances Added to Food database.)

Common culprits include chemicals added during the bleaching process and addition of "enzyme" / other ingredients that help improve baking consistency. Some examples:

https://www.hfpappexternal.fda.gov/scripts/fdcc/index.cfm?se...