Feathers are a by-product of poultry processing operations.
Pressurized cooking of feathers is the primary method of processing used in preparing feather meal. Some bacteria have been identified that produce a feather digesting enzyme, that will convert the protein fraction into a digestible form . Pepsin digestibility is used as method of assessing the quality of feather meal. Normally a pepsin digestibility of 75 % is considered to be a minimum value to assure that the feather meal has been adequately processed.