This invention provides processes comprising contacting at least one unopened defeathered poultry carcass with water containing a microbiocidal composition, optionally opening and eviscerating at least one unopened defeathered poultry carcass that was wetted; subjecting at least one eviscerated poultry carcass to inside-outside washing with water containing a microbiocidal composition; placing at least one eviscerated poultry carcass in a chill tank into contact with chill water containing a microbiocidal composition; contacting parts of poultry resulting from processing of poultry containing a microbiocidal composition. The water in these processes contains a microbiocidal composition comprising I) one or more surfactants and II) a microbiocidal amount of a biocide. The surfactants include amine oxides and/or betaines. The biocides include various chlorine -based and bromine- based biocides; chlorine dioxide; and peracetic acid.