Inactivation and kinetics analysis of aerobic bacteria in pear juice exposed to high pressure carbon dioxide

Inactivation and kinetic analysis of aerobic bacteria in fresh pear juice exposed to high pressure carbon dioxide (HPCD) was investigated.The result showed that the log reduction of aerobic bacteria increased with increasing temperature, pressure and treatment time significantly (p<0.05) .At an identical temperature and treated for the same time, much more log reduction of aerobic bacteria was achieved by HPCD than by heat treatment, indicating temperature played a synergistic role during HPCD treatment.The maximum log reduction was 2.66-log and obtained at 30MPa、40℃ and 60min.The survival curves of aerobic bacteria in fresh pear juice were well fitted with the Weibull model, and model parameters such as a value (scale factor) and b value (shape factor) decreased with increasing pressure or temperature.