Our supplies says: “The USA pig ears are blanched in boiling water and then dipped into an ice bath. This process helps remove the hair. They are then baked at a low temperature. There are no additives, preservatives, or chemicals used in the manufacturing process. Ears are cartilage, which contain collagen, but also have a high fat content. They may not be appropriate for dogs who need to lose weight or have a metabolic disease, such as pancreatitis. There will be a slight variation in each ear. We recommend this savory chew for all dogs!”