Antimicrobial Effects of Pressured Carbon Dioxide in a Continuous Flow System

ABSTRACT The application of microbubbles of pressured CO 2 greatly increased CO 2 concentration in the solution treated. By treatment at 6 MPa, 35°C and average residence time 15 min, L. brevis was completely inactivated at the level of dissolved CO 2 ,γ≧ 11 (γ, Kuenen's gas absorption coefficient). E. coli and S. cerevisiae required γ≧ 17, and T. versatilis required γ≧ 21 for complete inactivation. Z. rouxii could be sterilized at 20 MPa and 26. A comparison of the continuous and batch method showed that L. brevis was inactivated completely under pressured CO 2 > 0.16 g/cm 3 with the continuous method and >0.9 g/cm 3 with the batch method.