title: Water properties in cream cheeses with variations in pH, fat, and salt content and correlation to microbial survival.
abstract: Water mobility and distribution in cream cheeses with variations in fat (4, 15, and 26%), added salt (0, 0.625, and 1.25%), and pH (4.2, 4.7, and 5.2) were studied using (1)H NMR relaxometry. The cheese samples were inoculated with a mixture of Listeria innocua, Escherichia coli O157 and Staphylococcus aureus, and partial least-squares regression revealed that (1)H T(2) relaxation decay data were able to explain a large part of the variation in the survival of E. coli O157 (64-83%). However, the predictions of L. innocua and S. aureus survival were strongly dependent on the fat/water content of the samples. Consequently, the present results indicate that NMR relaxometry is a promising technique for predicting the survival of these bacteria; however, the characteristics of the sample matrix are substantial.
authors.affiliation: Department of Food Science, Faculty of Science and Technology, Aarhus University, Årslev, Denmark. Moeller@agrsci.dk
authors.forename: Sandie M
authors.initials: SM
authors.lastname: Møller
authors.forename: Tina B
authors.initials: TB
authors.lastname: Hansen
authors.forename: Ulf
authors.initials: U
authors.lastname: Andersen
authors.forename: Søren K
authors.initials: SK
authors.lastname: Lillevang
authors.forename: Anitha
authors.initials: A
authors.lastname: Rasmussen
authors.forename: Hanne C
authors.initials: HC
authors.lastname: Bertram
mesh_terms: D002611:Cheese / Q000032:analysis* / Q000382:microbiology*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000254:growth & development; D005223:Fats / Q000032:analysis*; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D008087:Listeria / Q000254:growth & development; D009682:Magnetic Resonance Spectroscopy; D012965:Sodium Chloride / Q000032:analysis*; D013211:Staphylococcus aureus / Q000254:growth & development; D014867:Water / Q000032:analysis*
chemical_list: D005223:Fats; D014867:Water; D012965:Sodium Chloride