Isolation of Salmonella Typhimurium, Listeria monocytogenes and coagulase-positive Staphylococcus from salami sold at street fairs in Porto Alegre, Brazil

Abstract

Salami is a ready-to-eat (RTE) product frequently purchased at street fairs in Porto Alegre. Salmonella enterica, Listeria monocytogenes, and coagulase-positive Staphylococcus (CPS) are important causes of foodborne disease and can be transmitted through the consumption of RTE foods. The aim of this study was to evaluate the presence of these pathogens in salami sold at street fairs. Ninety salami samples from three commercial brands available at street fairs were analyzed by routine bacteriological methods for Salmonella spp. and Listeria spp., as well as enumeration of CPS. In addition, two samples from each commercial brand were analyzed for water activity (aw). Samples of brand A showed aw values (0.938 and 0.942) above those set by the legislation, while brand B (0.849 and 0.860) and brand C (0.826 and 0.854) were compliant. Microbiological analyses showed that 67.7% were negative to all investigated bacteria. Salmonella Typhimurium was isolated from 4.4% (4/90) of salami samples, all from commercial brand A. Listeria monocytogenes was detected in 3.3% (3/90) of samples, from commercial brands B and C. Moreover, 7.7% (7/90) of samples contained CPS populations non-compliant with legislation. Although the great majority of salami sold at street fairs of Porto Alegre was compliant with standards, S. enterica, L. monocytogenes, and CPS ≥ 5 × 103 cfu.g-1 could be found in this RTE product. Therefore, control measures in the processing industry and consumer’s education about foodborne illness prevention should be maintained.

Survival assessment of Salmonella enterica in inoculated pork salami

“…Moreover, these stages are used for the control of pathogens in products such as salami, which does not undergo heat treatment (Lindqvist & Lindblad, 2009). However, because of the lack of standardization in these steps, salami available in the Brazilian retail market may present physical-chemical parameters outside of the permitted limits (Caccioppoli, Custódio, Vieira, Coelho, & Glória, 2006;Werlang et al, 2019).…”

“…This pathogen was reported in 11.3% of the confirmed outbreaks, a frequency that is very likely underestimated (Ministério da Saúde [MS], 2019). There are reports on the presence of S. enterica in salami at the retail level (Werlang, Haubert, Peter, & Cardoso, 2019), although the Brazilian standard for meat products is the absence of S. enterica in a 25 gram sample (Resolução RDC nº 12, 2001). One possible reason for cases of Salmonella contamination in salami may be the occurrence of failures in the antimicrobial hurdles (low Aw and pH) imposed during manufacturing.…”