But there are different levels of respirators, some with filters for organic vapors, which I think you'd want if your goal is lowering diacetyl and 2,3-pentanedione exposure.
Evidence:
https://www.aiha.org/events/AIHce/AIHceAbstracts/Pages/Respi...
Section "SR-101-02 Determination of the Service Life of Air-Purifying Respirators against 2,3-Pentanedione"