Abstract: A treatment material containing carbon monoxide and a carrier liquid is applied to a meat product to produce a desired carbon monoxide content in the meat product. The concentration of carbon monoxide in the added liquid produces a desired carbon monoxide saturation level distributed substantially evenly in the treated area of the meat product. The treated area may be just at the surface of the meat product or throughout the volume of the meat product. Additional treatment liquids or fluids may be added to the meat product as a pre-treatment before application of the carbon monoxide bearing treatment material or as a post-treatment after the application of the carbon monoxide bearing treatment material.