Analysis of the Variability in the Number of Viable Bacteria after Mild Heat Treatment of Food
Autor: | G. D. García de Fernando, Carmen Pin, María R. Rodríguez, Juan Aguirre |
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Rok vydání: | 2009 |
Předmět: |
Hot Temperature
Time Factors Food Handling medicine.medical_treatment Sodium Population Colony Count Microbial chemistry.chemical_element Pseudomonas fluorescens Sodium Chloride Bacterial Physiological Phenomena Applied Microbiology and Biotechnology Enterococcus faecalis Microbiology medicine Animals Food microbiology Food science education Saline education.field_of_study Microbial Viability Ecology biology biology.organism_classification Milk chemistry Food Microbiology Listeria Bacteria Food Science Biotechnology |
Zdroj: | Applied and Environmental Microbiology. 75:6992-6997 |
ISSN: | 1098-5336 0099-2240 |
DOI: | 10.1128/aem.00452-09 |
Popis: | Variability in the numbers of bacteria remaining in saline solution and whole milk following mild heat treatment has been studied with Listeria innocua , Enterococcus faecalis , Salmonella enterica serovar Enteritidis, and Pseudomonas fluorescens . As expected, the most heat-resistant bacterium was E. faecalis , while P. fluorescens was the least heat resistant, and all bacteria showed greater thermal resistance in whole milk than in saline solution. Despite the differences in the inactivation kinetics of these bacteria in different media, the variability in the final number of bacteria was affected neither by the species nor by the heating substrate, but it did depend on the intensity of the heat treatment. The more severe the heat treatment was, the lower the average number of surviving bacteria but the greater the variability. Our results indicated that the inactivation times for the cells within a population are not identically distributed random variables and that, therefore, the population includes subpopulations of cells with different distributions for the heat resistance parameters. A linear relationship between the variability of the log of the final bacterial concentration and the logarithmic reduction in the size of the bacterial population was found. |
Databáze: | OpenAIRE |
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