Czech J. Food Sci., 2021, 39(1):42-48 | DOI: 10.17221/201/2020-CJFS

Modelling the inactivation of Staphylococcus aureus at moderate heating temperaturesOriginal Paper

Veronika Lehotová^*,1, Karla Miháliková², Alžbeta Medveďová¹, Ľubomír Valík¹

¹ Department of Nutrition and Food Quality Assessment, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava, Slovakia

² ALFA BIO s.r.o., Kremnička, Banská Bystrica Slovakia

The survival of bacterial contaminants at moderate processing temperatures is of interest to many food producers, especially in terms of the safety and quality of the final products. That is why the heat resistance of Staphylococcus aureus 2064, an isolate from artisanal Slovakian cheese, was studied in the moderate temperature range (57-61 °C) by the capillary method. The fourth decimal reduction time t_4D- and z-values were estimated in two steps by traditional log-linear Bigelow and non-linear Weibull models. In addition, a one-step fitting procedure using the Weibull model was also applied. All the approaches provided comparable t_4D-values resulting in the following z-values of 11.8 °C, 12.3 °C and 11.3 °C, respectively. Moreover, the one-step approach takes all the primary data into z-value calculation at once, thus providing a more representative output at the reasonable high coefficient of determination R₂ = 0.961

Keywords: isothermal inactivation; S. aureus; capillary method; predictive microbiology

Published: February 26, 2021  Show citation