Microbial analysis of commercially available US Queso Fresco

Journal of Dairy Science
Maxwell J HolleM J Miller

Abstract

Queso Fresco (QF), a fresh Hispanic-style cheese, is often associated with Listeria monocytogenes outbreaks and recalls. Queso Fresco's susceptibility to bacterial contamination is partially due to its high pH and moisture content as well as Listeria's tolerance for the salt content typical for QF. Nine different brands of US QF, 2 packages from 4 different lots (to account for temporal variability), were sampled. The pH, salt content, and moisture content were analyzed in addition to microbial testing including yeasts and molds, coliforms, lactic acid bacteria enumeration, and L. monocytogenes counts. The cheeses were also inoculated with a cocktail of 5 food and human isolates of food-borne outbreak-associated Listeria monocytogenes strains to evaluate how the differences between brands influenced Listeria growth. Three of the cheeses underwent additional genus-level microbial analysis using extracted 16S rDNA, allowing for phylogenetic analysis between bacterial taxa including diversity and relative abundance. We found little variation between the sampled QF pH (range = 6.62-6.86), salt content (1.53-2.01%), and moisture content (43.90-54.50%). Yeasts and molds were below the detection limit of enumeration in all of the chee...Continue Reading

References

May 22, 2004·BioTechniques·Zhongtang Yu, Mark Morrison
Apr 9, 2008·Journal of Food Protection·Agnes Kilonzo-NthengeSandria L Godwin
Mar 27, 2009·Journal of Applied Microbiology·S A BurgessS H Flint
Apr 13, 2010·Nature Methods·J Gregory CaporasoRob Knight
Jul 20, 2010·Cirugía española·Pablo Moreno De La Santa BarajasMaria L Choren Durán
Nov 30, 2012·Nucleic Acids Research·Christian QuastFrank Oliver Glöckner
Jun 4, 2013·Journal of Food Protection·M E Macías-RodríguezM R Torres-Vitela
Jun 25, 2013·Applied and Environmental Microbiology·Nicholas A Bokulich, David A Mills
Mar 20, 2014·International Journal of Food Microbiology·Marie-Christine MontelFrançoise Berthier
Aug 3, 2014·Food Microbiology·Alejandro Aldrete-TapiaMontserrat Hernández-Iturriaga
Dec 17, 2014·PloS One·Patricio JeraldoNicholas Chia
Oct 12, 2015·Journal of Dairy Science·M L Van TassellM J Miller
Jan 17, 2016·Current Opinion in Biotechnology·Nicholas A BokulichDavid A Mills
Nov 9, 2016·MSystems·Lisa QuigleyPaul D Cotter
Feb 6, 2017·Journal of Dairy Science·Maxwell L Van TassellMichael J Miller
Feb 13, 2017·Journal of Dairy Science·L A Ibarra-SánchezM J Miller
Mar 17, 2017·Scientific Reports·Ephantus J MuturiChang-Hyun Kim
Sep 1, 1991·Journal of Food Protection·Constantin GenigeorgisThomas B Farver

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