Escherichia coli and Enterobacteriaceae counts on poultry carcasses along the slaughter processing line, factors influencing the counts and relationship between visual faecal contamination of carcasses and counts: a review

Abstract

A literature review was conducted covering the period 2000-2012 to gather information concerning the presence and counts of E. coli and Enterobacteriaceae on carcasses during different stages of the slaughter processing line (review question 1); risk factors that could explain the variability of the counts of the indicator organisms (review question 2) and the relationship between the counts of indicator organisms and visual faecal contamination on carcasses (review question 3). In total, 72 papers, providing pertinent data for the scopes of the search, were collected on poultry. A certain level of variability was evidenced among different studies and some variables like the indicator organism considered, the sampling and analytical methods used, the use of chlorine, the setting where the studies were carried out render the available data barely comparable. In relation to review question 1, the steps of the processing line where a decrease of E. coli was more evident were scalding, washing and chilling; furthermore as regards Enterobacteriaceae counts a decrease was observed at the scalding and washing steps. Considering review question 2, risk factors related to batch and slaughtering process were evaluated. In general when a risk factor was investigated by several studies results were hardly in agreement. Taking into account the slaughter process it is evident that plant features have an influence on indicator bacteria loads but considering each investigated risk factor no reliable conclusions can be drawn. In relation to review question 3, despite the retrieved studies were quite limited, the data obtained suggested that the presence of visible faecal contamination has no predictive value for estimating the microbial quality of the carcasses.

Quantitative microbiological slaughter process analysis in a large-scale Swiss poultry abattoir

“…This was in agreement with other studies that reported a decrease in E. coli and Enterobacteriaceae after washing, regardless of whether chlorine was added to the water (Berrang & Bailey, 2009;Kemp, Aldrich, Guerra, & Schneider, 2001;Northcutt, Berrang, Smith, & Jones, 2003;Oyarzabal, Hawk, Bilgili, Warf, & Kemp, 2004;Stopforth et al, 2007) or not (Goksoy, Kirkan, & Kok, 2004;González-Miret, Escudero-Gilete, & Heredia, 2006;Svobodová, Bořilová, Hulánková, & Steinhauserová, 2012). A systematic literature review commissioned by the EFSA showed that fecal contaminants (Enterobacteriaceae, E. coli) changed in the range of -0.05 to +0.83 CFU per ml rinse water or cm 2 after the evisceration step (Barco, Belluco, Roccato, & Ricci, 2014). Reduced microbial counts on the carcass after washing may either be due to a real reduction in microbial contamination, or caused by a more even redistribution of bacteria on a carcass, resulting apparently lower counts per area, while the total amount of bacteria on the carcass remains largely unchanged.…”

Usefulness of Escherichia coli and Enterobacteriaceae as Process Hygiene Criteria in poultry: experimental study

“…The present document is the report on the experimental study. The report of the extensive literature review is published as two separate external scientific reports (Barco et al, 2014a;Barco et al, 2014b).…”

“…Relevant information to be included in the questionnaires was selected according to information gathered through the extensive literature review (Barco et al, 2014b) and incorporating the suggestions of veterinarians responsible for the selected slaughterhouses that were contacted and involved at the very beginning of the study. The veterinarians were requested to complete the slaughterhouse questionnaire at the first visit, while the batch questionnaire was filled in during each visit.…”

“…The present document is the report on the experimental study in broiler slaughterhouses. The extensive literature search for available data on E. coli and Enterobacteriaceae on carcasses of poultry and pig and ruminant carcasses and are published as two separate external scientific reports (Barco et al, 2014a;Barco et al, 2014b).…”

The Efficacy of Air Spray Chilling and Its Impact on Microbial Quality of Broiler Carcasses

“…For Enterobacteriaceae the data obtained were quite controversial, and in some cases limited increases of the counts at the end of the air chilling process were reported (Barco et al, 2014). Salmonella was not detected in either of the samples.…”