Comparison of Excision, Swabbing and Rinsing Sampling Methods to Determine the Microbiological Quality of Broiler Carcasses

Abstract

Skin excision, swabbing with cotton wool and whole carcass rinse are three common sampling methods of poultry carcasses.The objective of this study was to compare the three different sampling methods for enumeration and monitoring of bacteria on broiler carcasses. Total viable counts, Pseudomonas spp., lactic acid bacteria, Brochothrix thermosphacta and Enterobacteriaceae recovered by each sampling method were enumerated using the pour plate technique. Rinsing and excision recovered a similar level (P > 0.05) of the total viable counts, whereas swabbing yielded a lower level (P < 0.05). For Pseudomonas spp., lactic acid bacteria and B. thermosphacta, rinsing recovered the highest counts,followed by excision and finally the swabbing.There was no significant difference (P > 0.05) to detect Enterobacteriaceae by the three methods. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to monitor bacterial constituents. Compared with rinsing, the dice coefficient was 69.2% for excision and 32.3% for swabbing. The results revealed that great differences existed among the sensitivity of microorganism detection by the three methods, rinsing > excision > swabbing. Considering the bacterial recovery and DGGE profile, rinsing seems to be the preferable sampling method for enumeration and monitoring of bacteria on broiler carcasses whereas swabbing is poor. PRACTICAL APPLICATIONSThis work compared the efficiency of three sampling methods (excision, swabbing and rinsing) to evaluate bacteria on broilers using culture-dependent and cultureindependent methods. The results indicate that whole carcass rinse would be a preferable sampling method to monitor the bacteria on broiler carcasses, especially using the culture-independent method.

Escherichia coli and E nterobacteriaceae counts on poultry carcasses along the slaughterline: A systematic review and meta-analysis

“…As regards sampling method it has been demonstrated that, although tissue excision (both skin and meat) provided the highest counts of indicator microorganisms, the rinsing method is fully comparable with tissue excision, when used for process hygiene assessment purpose (Cox et al, 2010;Gill, Badoni, Moza, Barbut, & Griffiths, 2005), while the swabbing method is less effective (Cossi, de Almeida, Dias, de Arruda Pinto, & Nero, 2012;Zhang, Ye, Xu, Zhou, & Cao, 2012). However, when bacteria such as E. coli are present at low levels on poultry carcass portions, rinsing is the most effective technique compared with excision sampling and swabbing represents a valid alternative.…”

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

“…Swabbing and excision offer practical advantages over carcass rinse, because of the ease and rapidity of sample collection and the smaller amount of enrichment medium required (Zhang et al, 2011). Swabbing and excision offer practical advantages over carcass rinse, because of the ease and rapidity of sample collection and the smaller amount of enrichment medium required (Zhang et al, 2011).…”

“…As far as swabbing is concerned, it is generally accepted that for poultry carcasses, this method is less effective in recovering indicator bacteria than excision or rinsing Zhang et al, 2011;Cossi et al, 2012). The lower recovery level obtained by using swabbing method could be due to the topography of the poultry skin or to the attachment of bacteria to the skin (Zhang et al, 2011).…”

“…Collection of relatively large numbers of whole carcasses rinse samples, especially in the case of large sized birds, would be impractical and economically demanding . Swabbing and excision offer practical advantages over carcass rinse, because of the ease and rapidity of sample collection and the smaller amount of enrichment medium required (Zhang et al, 2011). Moreover, excision, in particular of neck samples, is easier to perform because carcasses can be sampled without being removed from the processing line (Hutchison et al, 2006).…”

Biosensors for rapid detection of Salmonella in food: A review

“…The International Organization for Standardization (ISO) has given recommended sampling methods for different types of food (e.g., ISO/TS 17728:2015 for food and animal feed, ISO 707:2008 for milk and milk products, and ISO 17604:2015 for carcasses). For example, excision, swabbing, and rinsing are three common methods for poultry carcasses sampling (Zhang, Ye, Xu, Zhou, & Cao, 2012). Generally, they are applicable with acceptable bacteria recoveries.…”