title: Comparison of Primary Models to Predict Microbial Growth by the Plate Count and Absorbance Methods.
abstract: The selection of a primary model to describe microbial growth in predictive food microbiology often appears to be subjective. The objective of this research was to check the performance of different mathematical models in predicting growth parameters, both by absorbance and plate count methods. For this purpose, growth curves of three different microorganisms (Bacillus cereus, Listeria monocytogenes, and Escherichia coli) grown under the same conditions, but with different initial concentrations each, were analysed. When measuring the microbial growth of each microorganism by optical density, almost all models provided quite high goodness of fit (r(2) > 0.93) for all growth curves. The growth rate remained approximately constant for all growth curves of each microorganism, when considering one growth model, but differences were found among models. Three-phase linear model provided the lowest variation for growth rate values for all three microorganisms. Baranyi model gave a variation marginally higher, despite a much better overall fitting. When measuring the microbial growth by plate count, similar results were obtained. These results provide insight into predictive microbiology and will help food microbiologists and researchers to choose the proper primary growth predictive model.
authors.affiliation: Departamento de Matemática Aplicada, EPSA, Universidad Politécnica de Valencia, Plaza Ferrandiz y Carbonell, s/n, 03801 Alcoy, Spain.
authors.forename: María-Leonor
authors.initials: ML
authors.lastname: Pla
authors.affiliation: Departamento de Matemática Aplicada, EPSA, Universidad Politécnica de Valencia, Plaza Ferrandiz y Carbonell, s/n, 03801 Alcoy, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Oltra
authors.affiliation: Departamento de Ingeniería de Alimentos y del Equipamiento Agrícola, Universidad Politécnica de Cartagena, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Paseo Alfonso XIII 48, 30203 Cartagena, Spain.
authors.forename: María-Dolores
authors.initials: MD
authors.lastname: Esteban
authors.affiliation: Departamento de Ingeniería de Alimentos y del Equipamiento Agrícola, Universidad Politécnica de Cartagena, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Paseo Alfonso XIII 48, 30203 Cartagena, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: Andreu
authors.affiliation: Departamento de Ingeniería de Alimentos y del Equipamiento Agrícola, Universidad Politécnica de Cartagena, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Paseo Alfonso XIII 48, 30203 Cartagena, Spain ; Instituto de Biotecnología Vegetal, Universidad Politécnica de Cartagena, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Edificio I+D+I, Muralla del Mar, 30202 Cartagena, Spain.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Palop
mesh_terms: D001409:Bacillus cereus / Q000254:growth & development*; D004926:Escherichia coli / Q000254:growth & development*; D005516:Food Microbiology; D006801:Humans; D007700:Kinetics; D008089:Listeria monocytogenes / Q000254:growth & development*; D008962:Models, Theoretical