Recovery of Salmonellae from Chilled Broiler Carcasses as Affected by Rinse Media and Enumeration Method

Abstract

Distilled water (DW) and 0.85% NaCl (PS) were evaluated as carcass rinse media for recovery of total aerobic bacteria (APC), total coliforms (TC), Escherichia coli, and salmonellae from broiler carcasses. Salmonellae were enumerated by two methods, most-probable-number (MPN) and centrifugation-plating onto dulcitol novobiocin agar (DBN). Commercially processed chilled broiler carcasses (10/trial, 3 trials) were aseptically cut in half, and each half was rinsed (1 min) with either 250 ml DW or PS. Carcass rinses were recovered and analyzed for populations of APC, TC, E. coli, and salmonellae.Recovery of APC, TC, and E. coli were not affected (P>.05) by rinse media; however, significant trial effects were present. Recovery of salmonellae was influenced by rinse media as well as by enumeration method. Using the MPN procedure, salmonellae were detected on 20 and 27% of carcass halves using PS and DW, respectively, whereas with DBN, salmonellae were recovered from 33% of PS-rinsed carcass halves and none of those rinsed with DW. Incidence of salmonellae on individual carcass halves did not correlate between either the two enumeration methods or rinse media. With both enumeration methods, the extent of salmonellae contamination was <1 CFU/ml of rinse media. Rinsing carcasses with PS offered no advantages for recovery of APC, TC, and E. coli; however, salmonellae recovery on DBN was enhanced by PS as compared to DW rinse.