A model based on absorbance data on the growth rate of Listeria monocytogenes and including the effects of pH, NaCl, Na-lactate and Na-acetate.
Int J Food Microbiol
; 47(1-2): 99-109, 1999 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-10357278
ABSTRACT
A mathematical model was developed for predicting the growth of L. monocytogenes at 9 degrees C in the presence of 70 ppm sodium nitrite, and at different levels of pH (5.5-6.5), sodium chloride (1.0-4.0%), sodium lactate (0-0.5%) and sodium acetate (0-0.6%). Collection of the growth data was done using absorbance measurements in broth cultures and the absorbance measurement was evaluated. The model was compared to the Food MicroModel, and against the growth of L. monocytogenes in a vacuum-packed meat product stored at 9 degrees C. A linear relationship was obtained, for the absorbance data on different dilutions of the inoculum, in the absorbance interval studied. There was also a linear relationship between the values of the maximum specific growth rates derived from the absorbance and the ones derived from viable count measurements; and corrections were made accordingly. The statistical evaluation showed that all the main factors, i.e. pH, sodium chloride, sodium lactate and sodium acetate were statistically significant for the growth rate of L. monocytogenes. Comparison to the Food MicroModel (FMM) showed a slight underprediction for the developed model (bias = 0.84). The predictions were, on average, within 20% of the FMM predictions (n = 10). Validation against the observed growth of L. monocytogenes inoculated into an emulsion type of sausage (n = 4) also showed a slight underprediction by the model. The predictions were, on average, 16% below the observed values in the sausage (Bias 0.84, Accuracy 1.26).
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Microbiologia de Alimentos
/
Listeria monocytogenes
/
Produtos da Carne
/
Modelos Biológicos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Int J Food Microbiol
Assunto da revista:
CIENCIAS DA NUTRICAO
/
MICROBIOLOGIA
Ano de publicação:
1999
Tipo de documento:
Article