Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 30, 2005
Publication Date: February 1, 2006
Citation: Berrang, M.E., Smith, D.P., Hinton Jr, A. 2006. Application of distilled white vinegar to counter the increase in campylobacter numbers on broiler skin during feather removal. Journal of Food Protection. 69(2):425-427. Interpretive Summary: Campylobacter is a human pathogen that is often associated with poultry and poultry products and often present on the outer and inner surfaces of broilers when they arrive at a processing plant. After the birds are processed lower numbers of Campylobacter found. However, during one of the first processing steps, an increase in Campylobacter numbers is found on chicken skin. The machine used for feather removal operates by means of rubber “fingers” spinning at high speed which pull the feathers off of the carcass. These fingers can also apply pressure to the abdomen and may incidentally force contaminated fecal matter out of the anus onto the skin of the carcass. In this study we tested vinegar as a food grade antimicrobial chemical for its ability to lower skin contamination with Campylobacter. Vinegar was placed in the lower gut of broiler carcasses before they entered the feather picking machine. Control carcasses without vinegar experienced a 3 log increase in Campylobacter numbers on breast skin due to passage through a commercial style feather picking machine. Conversely, carcasses treated with vinegar had an increase of only 1 log, 99% less than the control. These data indicate that the increase in broiler carcass Campylobacter contamination associated with automated feather removal can be moderated by application of a food grade antimicrobial early in processing. This information can be used by researchers to further explore this type of treatment and by processors to lower Campylobacter contamination on fully processed broilers.
Technical Abstract: Broiler carcass Campylobacter numbers increase during automated commercial feather removal due to escape of highly contaminated gut contents from the cloaca. Vinegar which is 5 % acetic acid is known to have antimicrobial action. The objective of this study was to counter the increase in Campylobacter by placing vinegar in the colon prior to carcasses entering the feather picking machine. Broilers were stunned, killed and bled in a pilot processing plant. Prior to scalding, distilled white vinegar (5% acetic acid) was placed into the colon. After scalding, before automated feather removal, Campylobacter numbers were determined on breast skin of broilers. Campylobacter numbers on carcass breast skin was measured again after passage through a commercial style feather picking machine. Campylobacter numbers on control carcasses increased during feather picking from log 1.3 to log 4.2 and log 4.0 cfu/sample for untreated and water treated carcasses respectively. Campylobacter numbers on carcasses treated with vinegar also increased but to a lesser extent, resulting in log 2.6 cfu/sample. Application of a food grade antimicrobial (such as vinegar) in the cloaca prior to scald can affect the increase in broiler carcass Campylobacter numbers associated with de-feathering.