These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Inactivation kinetics of selected aerobic and anaerobic bacterial spores by pressure-assisted thermal processing.
    Author: Ahn J, Balasubramaniam VM, Yousef AE.
    Journal: Int J Food Microbiol; 2007 Feb 15; 113(3):321-9. PubMed ID: 17196696.
    Abstract:
    The combined pressure-thermal inactivation kinetics of spores from three strains of anaerobic (Clostridium sporogenes, C. tyrobutylicum, and Thermoanaerobacterium thermosaccharolyticum), and six strains of aerobic (Bacillus amyloliquefaciens and B. sphaericus) bacteria were studied. Spores of these bacteria were prepared in deionized water and treated in a custom-made kinetic tester over various pressure (0.1 and 700 MPa) and thermal (105 and 121 degrees C) combinations. Survivor data were modeled using log-linear and Weibull models to obtain relevant kinetic parameters. In comparison to thermal treatment alone, the combined pressure-thermal conditions accelerated the inactivation of the spores tested. A measurable fraction of spore populations was inactivated during the pressure come-up time. Pressure-assisted thermal processing (PATP) at 700 MPa and 121 degrees C for 1 min inactivated up to 7-8 log for some of spores tested. Among bacteria evaluated, based on survivor curve data T. thermosaccharolyticum, B. amyloliquefaciens Fad 82, and Fad 11/2 were found to produce the most PATP-resistant spores. PATP inactivation plots showed characteristic upward curvature, which is indicative of the tailing behavior. Since both log-linear and Weibull kinetic models did not consider microbial reduction during process come-up time, our results demonstrated that the estimated model parameters were not adequate to compare combined pressure-thermal resistance of various bacterial spores tested.
    [Abstract] [Full Text] [Related] [New Search]