A method for suppressing the formation of ammonia comprising providing a carrier material to a container having a headspace; providing a bacteria, an acidifier and an odor inhibitor to the carrier material, the bacteria comprising Staphylococcus-xylosus or Staphylococcus-cohnii bacteria, and the odor inhibitor comprising a salt of an aminopolycarboxylic acid compound; and applying animal waste to the carrier material; wherein there is a 5 to 98 percent improvement of ammonia content in the headspace as compared to an untreated control comprising a container containing the carrier material and the bacteria and not contain the odor inhibitor.