An acidified sodium chlorite (ASC) solution was investigated for its antimi
crobial effects on broiler carcasses processed under conditions similar to
those used in U.S. commercial poultry facilities. Of particular interest wa
s the ability of the ASC solution to reduce natural bioburden in a prechill
procedure. A number of parameters such as pretreatment washing of carcasse
s with water (no wash versus water wash), ASC concentration (500, 850, and
1,200 ppm), method of application (spray versus dip), and method of acid ac
tivation (phosphoric acid versus citric acid) were explored to evaluate dis
infection conditions. ASC dip solutions (18.9 liters) were freshly prepared
for groups of five prechill eviscerated carcasses per treatment (n = 10 ca
rcasses). ASC treatment was shown to be an effective method for significant
ly reducing naturally occurring microbial contamination on carcasses. Reduc
tions following immersion dipping were demonstrated at all disinfectant con
centrations for total aerobes (82.9 to 90.7%), Escherichia coli (99.4 to 99
.6%), and total coliforms (86.1 to 98.5%). Additionally, testing showed tha
t ASC solutions maintained stable pH and minimal chlorite ion concentration
deviations throughout each treatment. The results of the parameter evaluat
ions indicated that maximal antimicrobial activity was achieved in carcasse
s that were prewashed and then exposed to a 5-s dip in a solution containin
g phosphoric acid- or citric acid-activated ASC. At 1,200 ppm ASC, a mild b
ut transitory whitening of the skin was noted on dipped carcasses. The resu
lts support the methods currently approved by the U.S. Department of Agricu
lture for the use of ASC solutions as a prechill antimicrobial intervention
in U.S. poultry processing plants.