Inactivation of Bacillus spores by the supercritical carbon dioxide micro-bubble method

Bacillus spores were effectively inactivated by the supercritical (SC) CO2 micro-bubble method, The micro-bubble SC CO2 treatment of B. cereus, B. subtilis, B. megaterium, B. polymyxa, and B. coagulans at 40 degrees C and 30 MPa for 30 min produced greater reduction (about 3 log cycles of reduction) than a similar treatment without a filter, The SC CO2 treatment of B. polymyxa, B. cereus, and B. subtilis spores at 45 degrees C, 50 degrees C, and 55 degrees C, respectively, and 30 MPa for 60 min resulted in a 6-log cycle reduction of survival, The SC CO2 treatment under the foregoing conditions should offer higher efficiency than that of heat treatment at 100 degrees C for 60 min, In addition, the SC CO2 treatment (30 MPa, 60 degrees C, 30 min) of B. polymyxa and B. cereus spores also produced a 6-log cycle reduction.