Processing and Products

The prevalence and serogroups of Salmonella recovered following air chilling were determined for both enriched neck skin and matching enriched whole carcass samples. Commercially processed and eviscerated carcasses were air chilled to 4°C before removing the neck skin (8.3 g) and stomaching in 83 mL buffered peptone water. The remaining carcass was subjected to whole carcass enrichment in 500 mL buffered peptone water. Both neck skins and whole carcasses were incubated at 37°C for 24 h before aliquots were transferred to selective enrichment broths (RV and TT) and incubated at 37°C for 24 h. Following incubation, BGS and MLIA plates were streaked and incubated at 37°C for 24 h. Three typical colonies were individually stabbed into TSI and LIA slants and incubated at 37°C for 24 h. For neck skin samples, 14/18 were Salmonella-positive with 5 identified as serogroup C1, 8 serogroup C3, and 2 serogroup E. For whole carcasses 16/18 carcasses were Salmonella-positive with 1 identified as serogroup B, 6 serogroup C1, 9 serogroup C3, and 2 serogroup E. Two Salmonella serogroups were detected from one neck skin (C3/E) sample and 2 Salmonella serogroups were detected from 2 non-matched carcasses (C1/C3 and C3/E). All 4 of the Salmonella-negative neck skin samples had Salmonella-positive matching whole carcasses and the 2 Salmonella-negative whole carcasses had Salmonella-positive matching neck skin samples. Selecting 3 individual colonies, versus only one, from BGS and MLIA plates resulted in 2 additional Salmonella-positive neck skin samples (C1) and 2 additional Salmonella-positive carcasses (C1 and C3). In this study, individual neck skin enrichment (78%) and whole carcass enrichment (89%) sampling methodologies were comparable in the prevalence detection of Salmonella from matched air-chilled carcasses.