Baroinactivation of Staphylococcus epidermidis - mathematical model and its verification using human and cow milk

Staphylococcus epidermidis, commonly found on the human skin, may contaminate human milk. High-pressure pasteurisation of human milk under normal temperature preserves the majority of its protective agents. The objective of this study was to acquire baroinactivation data and develop a model for mode...

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Bibliographic Details
Main Authors: Ljuba Schlemmerová, Milan Houška, Vladimir Špelina, Jan Strohalm, Aleš Landfeld, Hana ŠmuhaŘová, Ilona Němcová, Karel Kýhos, Jiřina Průchová, Pavla Novotná, Pavel Měřička
Format: Article
Language:English
Published: Czech Academy of Agricultural Sciences 2009-04-01
Series:Czech Journal of Food Sciences
Subjects:
Online Access:https://cjfs.agriculturejournals.cz/artkey/cjf-200902-0007_baroinactivation-of-staphylococcus-epidermidis-mathematical-model-and-its-verification-using-human-and-cow-mi.php
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Summary:Staphylococcus epidermidis, commonly found on the human skin, may contaminate human milk. High-pressure pasteurisation of human milk under normal temperature preserves the majority of its protective agents. The objective of this study was to acquire baroinactivation data and develop a model for model solutions of pH = 6.4 to 7.2 and water activity aw = 0.99, in which baroinactivation of Staphylococcus epidermidis takes place. Decontamination data manifested exponential kinetics and the resulting model was described by the following equations: Dp = Dp, ref × 10 (Pref - P)/Z, Z = -123.90 pH2 + 1635.54 pH - 5210.49; Dp, ref = -8.89 pH2 + 121.02 pH - 408.34. The developed model was verified using pasteurised human milk and UHT-treated skimmed cow milk. The agreement between the experimental data and model-based prediction was very good for human milk. It was proved that the application of a pressure of 350 MPa for 10 min decreased the concentration of the working suspension of S. epidermidis in the model substrate by a minimum of five orders.
ISSN:1212-1800
1805-9317