Prevalence and characterization of Salmonella during pork sausage manufacturing

Authors: WOTTLIN, LAUREN - FORMER ARS EMPLOYEE; HARVEY, ROGER; NORMAN, KERI - TEXAS A&M UNIVERSITY; Droleskey, Robert - Bob; Andrews, Kathleen - Kate; JACKSON, STEVEN - TEXAS A&M UNIVERSITY; Anderson, Robin; Poole, Toni

Submitted to: Microorganisms
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/3/2024
Publication Date: 8/6/2024
Citation: Wottlin, L.R., Harvey, R.B., Norman, K.N., Droleskey, R.E., Andrews, K., Jackson, S.J., Anderson, R.C., Poole, T.L. 2024. Prevalence and characterization of Salmonella during pork sausage manufacturing. Microorganisms. 12(8). Article 1599. https://doi.org/10.3390/microorganisms12081599.
DOI: https://doi.org/10.3390/microorganisms12081599

Interpretive Summary: Salmonella is a foodborne bacterium that can cause sickness and sometimes death in humans who consume food contaminated with Salmonella. It is the most prevalent and expensive foodborne disease in the U.S. which costs billions of dollars in healthcare. Beef, poultry, and pork meat can become contaminated with Salmonella in processing plants. To prevent this, effective intervention procedures are in high demand. In this study, samples were taken from different stages, both pre- and post-intervention, in a pork processing plant and examined for presence of Salmonella. The presence or absence of Salmonella evaluated the effectiveness of prevention measures. Organic acid spray on pork carcasses and meat proved to be the most effective reducer of Salmonella on retail products from the processing plant. These informative results will help the food industry employ intervention steps that prevent Salmonella on food products during processing, which in turn should reduce human exposure to and subsequent disease from Salmonella.

Technical Abstract: Pork carcasses and meat may harbor Salmonella and contaminate other products during harvest and fabrication. A sausage processing plant in the Midwestern U.S. was sampled monthly for twelve months from May 2021 to April 2022 (except for December) to enumerate Salmonella and Enterobacteriaceae (EB) throughout sausage manufacturing to determine high-risk steps and efficiency of existing in-plant interventions. Furthermore, Salmonella serotypes and antimicrobial susceptibility were evaluated on a subset of samples recovered at the end phases of sausage fabrication. During collection, samples were taken from 8 sows through various steps of sausage production. Production steps represented were: 1) hide swab, pre-NaOH wash; 2) hide swab, post-NaOH wash; 3) carcass swab, pre-evisceration; 4) carcass swab, post-split and trim; 5) carcass swab, post-lactic acid wash; 6A) head swab, pre-wash; 6B) head meat, post-peracetic acid and lactic acid washes; 6) coarsely ground head and carcass meat from all 8 sows combined; 7A) trace lean from external suppliers; 7) spiced, chilled and fat-corrected batter; and 8) finished product samples from retail store-ready packaging. A total of 830 samples were tested. There were thirty-four Salmonella isolated which composed of thirty-two different serotypes. Only three isolates showed resistance to ampicillin. The remainder of isolates were pan-susceptible to antimicrobials. In conclusion, Salmonella and EB were significantly reduced (P<0.001) by acid washes at different stages of production and the results point out the beneficial effects of interventions to lessen Salmonella concentrations in retail product.