Effect of High-pressure CO₂ Processing on Bacterial Spores

Abstract

High-pressure CO₂ (HPCD) is a nonthermal technology that can effectively inactivate the vegetative forms of pathogenic and spoilage bacteria, yeasts, and molds at pressures less than 30 MPa and temperatures in the range of 20°C to 40°C. However, HPCD alone at moderate temperatures (20–40°C) is often insufficient to obtain a substantial reduction in bacterial spore counts because their structures are more complex than those of vegetative cells. In this review, we first thoroughly summarized and discussed the inactivation effect of HPCD treatment on bacterial spores. We then presented and discussed the kinetics by which bacterial spores are inactivated by HPCD treatment. We also summarized hypotheses drawn by different researchers to explain the mechanisms of spore inactivation by HPCD treatment. We then summarized the current research status and future challenges of spore inactivation by HPCD treatment.

Keywords:

• HPCD
• bacterial spore inactivation
• inactivation kinetics
• inactivation mechanism

FUNDING

This research work is supported by Grant No. 31171770 of the National Natural Science Foundation of China and “Novel Technologies and Equipments of Food Nonthermal Processing” (Project No. 2011AA100801) of the 863 High-Tech Plan of China.