Header
Menü schließen
| Inaktivierung von Mikroorganismen durch Sterilisation, Desinfektion oder Pasteurisierung Neue mathematische Modelle Rudolf Bliem und Werner Georg Nowak Universität für Bodenkultur Wien, Wien (Österreich) Inactivation of Microorganisms by Sterilization, Disinfection, and Pasteuriza-tion / New mathematical models Throughout the 20th century the kinetics of microbial inactivation have been described and calculated on the basis of the exponential model. This has offered little in terms of a logically satisfactory explanation, but the computations have served their purpose. In view of increas-ing demands on sterilisation techniques, the exponential model can no longer satisfy the needs for accuracy in the calculations of “sterilization times”, in particular at temperatures below 100 °C. This article presents a new approach to microbial inactivation, namely the concept of a “typical resistance time” of microorganisms, as well as refined methods of mod-elling the inactivation kinetics under a quantitative aspect. On the basis of the assumption that the individual microbial survival times obey a two-parameter distribution, such as the log-normal or the Gamma distribution, new model functions are established which correlate significantly better with all available test data than the classic exponential model. The predictions of “safe sterilizations times” differ considerably (up to a factor 2) between the old and the new approach. Key words Desinfektion • Hygiene • Mathematisches Modell • Pasteurisierung • Qualitätssicherung • Sterilisation |
|
|
pharmind 2004, Nr. 4, Seite 470
