Preliminary communication
Use of Frequency Distribution Functions to Establish Safe Conditions in Relation to the Foodborne Pathogen Bacillus cereus
Begoña Delgado
; Unidad Asociada UPCT-IATA (CSIC), Dpto. Ing. Alimentos y del Equipamiento Agrícola, Paseo Alfonso XIII 48, E-30203 Cartagena, Murcia, Spain
Paula M. Periago
; Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Dpto. Ciencia y Tecnología de Alimentos, Murcia, Spain
Raquel Conesa
; Unidad Asociada UPCT-IATA (CSIC), Dpto. Ing. Alimentos y del Equipamiento Agrícola, Paseo Alfonso XIII 48, E-30203 Cartagena, Murcia, Spain
Alfredo Palop
; Unidad Asociada UPCT-IATA (CSIC), Dpto. Ing. Alimentos y del Equipamiento Agrícola, Paseo Alfonso XIII 48, E-30203 Cartagena, Murcia, Spain
Pablo S. Fernández
; Unidad Asociada UPCT-IATA (CSIC), Dpto. Ing. Alimentos y del Equipamiento Agrícola, Paseo Alfonso XIII 48, E-30203 Cartagena, Murcia, Spain
Abstract
Minimal processing implementation greatly depends on a detailed knowledge of the effects of preservation factors and their combinations on the spoilage and foodborne pathogenic microorganisms. The effectiveness of mild preservation conditions will become increasingly dependent on a more stochastic approach linking microbial physiological factors with product preservation factors. In this study, the validity of frequency distributions to efficiently describe the inactivation and growth of Bacillus cereus in the presence of natural antimicrobials (essential oils) has been studied. For this purpose, vegetative cells were exposed to 0.6 mM of thymol or cymene, obtaining survival curves that were best described by the distribution of Weibull, since a tailing effect was observed. B. cereus was also exposed in a growth medium to a low concentration (0.1 mM) of both antimicrobials, separately or combined, and the lag times obtained were fitted to a normal distribution, which allowed a description of dispersion of the start of growth. This allowed a more efficient evaluation of the experimental data to establish safe processing conditions according to accurate parameters and their implementation in risk assessment.
Keywords
Bacillus cereus; natural antimicrobials; frequency distributions
Hrčak ID:
110488
URI
Publication date:
15.6.2005.
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