Presence of Listeria species in ready-made meatballs offered by sale under freezing or cooling preservation

İşleyici Ö., Sancak Y. C., Tuncay R. M., Atlan M.

ANKARA UNIVERSITESI VETERINER FAKULTESI DERGISI, vol.66, no.3, pp.281-288, 2019 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 66 Issue: 3
  • Publication Date: 2019
  • Doi Number: 10.33988/auvfd.475104
  • Journal Name: ANKARA UNIVERSITESI VETERINER FAKULTESI DERGISI
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.281-288
  • Keywords: Listeria monocytogenes, Listeria species, meatball, PCR, MONOCYTOGENES, CONTAMINATION, MEAT
  • Van Yüzüncü Yıl University Affiliated: Yes

Abstract

This study was conducted to detect contamination level of Listeria species in ready-made meatballs kinds that are stored under frozen or cooled conditions. In isolations and identifications of Listeria species from the samples, method approved and suggested by USDA/FSIS (United States Department of Agriculture/Food Safety and Inspection Service) was used. The strains that were identified to be Listeria monocytogenes with biochemical tests was verified as species through Real Time PCR method by using a primary pair specific to hly A gene location. In this study, a total number of 290 different type ready-made meatball samples were analysed. As a result of examining all samples was isolated L. monocytogenes in 32 (11.04%) samples, L. ivanovii in 9 (3.10%) samples, L. innocua in 22 (7.59%) samples, L. welchimerii in 8 (2.76%) samples and also L. seeligeri in 4 (1.38%) samples. In the serotyping of the 32 L. monocytogenes strains isolated from the samples; 15 isolated are found to be Type 1, where 3 strains are found to be Type 4, 11 strains to be type Poly and the rest 3 strains could not typified. The Mean pH and water activity values for the samples were found to be 6.62±0.56 and 0.985±0.007 respectively. In the result of the study, identifying Listeria species especially L. monocytogenes in cooled and frozen ready-made meatball samples studied suggest that such products whose consumption increased in the recent years pose important risk in terms of public health.

This study was conducted to detect contamination level of Listeria species in ready-made meatballs kinds that are stored under frozen or cooled conditions. In isolations and identifications of Listeria species from the samples, method approved and suggested by USDA/FSIS (United States Department of Agriculture/Food Safety and Inspection Service) was used. The strains that were identified to be Listeria monocytogenes with biochemical tests was verified as species through Real Time PCR method by using a primary pair specific to hly A gene location. In this study, a total number of 290 different type ready-made meatball samples were analysed. As a result of examining all samples was isolated L. monocytogenes in 32 (11.04%) samples, L. ivanovii in 9 (3.10%) samples, L. innocua in 22 (7.59%) samples, L. welchimerii in 8 (2.76%) samples and also L. seeligeri in 4 (1.38%) samples. In the serotyping of the 32 L. monocytogenes strains isolated from the samples; 15 isolated are found to be Type I, where 3 strains are found to be Type 4, 11 strains to be type Poly and the rest 3 strains could not typified. The Mean pH and water activity values for the samples were found to be 6.62 +/- 0.56 and 0.985 +/- 0.007 respectively. In the result of the study, identifying Listeria species especially L. monocytogenes in cooled and frozen ready-made meatball samples studied suggest that such products whose consumption increased in the recent years pose important risk in terms of public health.