African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5210

Full Length Research Paper

Identification of Salmonella isolated from pork sausage and evaluation of thermal and antimicrobial resistance of isolates

Francesca Silva Dias1*, Cíntia Lacerda Ramos2,  Amanda Rejane Alves de Ávila2, Marianna Rabelo Rios Martins Santos2 and Rosane Freitas Schwan2
1College of Veterinary Medicine, Federal University of San Francisco Valley, Rod. BR 407, Km 12, CEP 56.300-990, Petrolina, Pernambuco, Brazil. 2Biology Department, Federal University of Lavras, CEP: 37.200-000, Lavras, Minas Gerais, Brazil.
Email: [email protected]

  •  Accepted: 08 October 2013
  •  Published: 07 November 2013


Pork products are important reservoir of Salmonella. In Brazil, the consumption of pork sausage is high and the occurrence of Salmonella in product is usual. Salmonella occurrence was studied in twenty samples of fresh pork sausage. Pulsed-Field Gel Electrophoresis (PFGE) was performed to characterize Salmonella isolates. Their antimicrobial and heat resistance were also evaluated. Salmonella was detected in five samples of industrial pork sausage and six isolates were obtained and identified by phenotypic and genotypic methods: Salmonella enterica subsp. houtenae (two isolates) and serovars of Senterica subsp. enterica: Bareilly, Typhimurium, Paratyphi C and Paratyphi B. Salmonella houtenae and the serovars Paratyphi B and Typhimurium were resistant to three or more of antimicrobial agents tested. The Salmonella cocktail presented high heat resistance in pork sausage with D-values at 58, 62 and 65°C of 10.99, 5.29 and 2.16 min, respectively, and a z-value of 10.1°C. The evaluation of thermal and antimicrobial resistance of Salmonella can be useful for researchers and food industry involved in the management of pork product quality and resulting in improvements in microbiological safety. According to our results, the binomial effect of time and temperature can be utilized to pork industry in designing and estimating thermal processes specific for sausage. To consumers, a longer heating time ensures the microbiological quality of sausage and reduces the risk of salmonellosis.

Key words: Pulsed-field gel electrophoresis, pork product, food safety, salmonellosis.