Effect of High Pressure Carbon Dioxide Treatment on Bacillus subtilis in Pork
LI Feng-juan；ZHOU Xian-han
1. College of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009, China??
2. Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei 230009, China
Abstract：The effects of experimental conditions including temperature, pressure and dwell time on the efficacy of high pressure carbon dioxide (HPCD) treatment for inactivating Bacillus subtilis in pork were examined in this study. An orthogonal array design was used to optimize the operating conditions based on bacterial lethality. Besides, optimal chemical additives for enhancing the bactericidal effect of HPCD treatment against Bacillus subtilis were screened and the bactericidal mechanism of HPCD treatment was analyzed. HPCD was effective in inactivating Bacillus subtilis. The order of effect of the HPCD treatment conditions on bacterial lethality, listed in decreasing order, was as follows:pressure, dwell time and temperature, and their optimized values were 30 MPa, 60 min and 40℃, respectively, resulting in a lethal rate as high as 3.39. The simultaneous addition of inhibitor and inducer was the best way to enhance the inactivation of Bacillus subtilis by HPCD and the resulting lethal rate was as high as 5.16;moreover, better bactericidal effect was observed for inducer alone compared with inhibitor alone. Hence, we speculated that the bactericidal mechanism of HPCD against Bacillus subtilis may be achieved by first promoting spore germination and then killing vegetative cells.
2012, Vol. 26 
