A novel thermal treatment for microorganism inactivation, characterized by a veryrapid temperature increase (up to 30C/s) and a low final temperature (up to 65C)maintained for a relatively short holding time, has been recently presented andtested by the authors, showing microbial load reduction greater than 5 log unitsagainst several common bacteria and yeasts. With the aim of extending the possibleuse of the new thermal treatment to a wider microorganisms class, in thiswork the dynamic irreversible thermoporation (DIT) treatment was further testedon a well-known thermoresistant strain, the Enterococcus hirae: The results ofthese new experimental tests confirmed the reliability of the process, whichallowed to reach the 5 log microbial reduction once the adequate holding time wasemployed.The comparison with simple immersion in a thermostatic bath, where the veryslow heating process with 0.3C/s has been performed, confirmed the crucial roleof the thermal shock for the success of the treatment. The inactivation kinetics ofE. hirae in isothermal conditions immediately after the application of thermalshock has also been studied. Finally, the morphological analysis performedby using a scanning electron microscope clearly revealed the rupture of the cellmembrane, leading to identification of the process called dynamic irreversiblethermoporation (DIT).
|Numero di pagine||10|
|Rivista||Journal of Food Process Engineering|
|Stato di pubblicazione||Published - 2017|
All Science Journal Classification (ASJC) codes