期刊名称:Potravinarstvo : Scientific Journal for Food Industry
印刷版ISSN:1338-0230
电子版ISSN:1337-0960
出版年度:2012
卷号:6
期号:1
DOI:10.5219/179
出版社:Association HACCP Consulting
摘要:As the strains of S. aureus growing during fermentation of raw milk cheeses are exposed to the competitive growth of lactic acid bacteria and their metabolites, in this work, we characterized the growth of the strain S. aureus 2064 isolated from such environment against of water activity values and incubation temperature. Water activity of the tested media was adjusted by NaCl in the range from 0 % to 20.72 % and the experiments were carried out at 37 °C. It was found that the strain under study showed growth until NaCl concentration of 19.95 % in PCA broth. The complete growth cessation of S. aureus 2064 was observed at NaCl concentration higher than 20.72 %. The effect of water activity on the S. aureus 2064 lag-phase duration was described by the modified Davey model with discrepancy of 24.6 %. The growth rate dependence on water activity was described more precisely and reliably by Gibson model that provided the following validation indices: bias factor 0.999 and discrepancy factor 9.6 %. Based on the results we can conclude that secondary models used in this work were suitable to predict growth of S. aureus 2064, originally the ewes´cheese isolate.