Sterilization of microorganisms by the supercritical carbon dioxide micro-bubble method

Area of Science:

• Food Science
• Microbiology
• Chemical Engineering

Background:

• Microbial contamination poses a significant challenge in food processing and preservation.
• Effective sterilization methods are crucial for ensuring product safety and extending shelf life.
• Traditional sterilization techniques may impact food quality and nutritional value.

Purpose of the Study:

• To evaluate the efficacy of supercritical (SC) CO2 micro-bubble treatment for sterilizing specific microorganisms.
• To compare the sterilizing effectiveness of SC CO2 with gaseous (G) and liquid (LQ) CO2 treatments.
• To determine optimal conditions for SC CO2 sterilization.

Main Methods:

• Utilized supercritical (SC) CO2 micro-bubble technology for sterilization.
• Employed Lactobacillus brevis and Saccharomyces cerevisiae as test microorganisms.
• Compared SC CO2 treatment with gaseous (G) and liquid (LQ) CO2 methods under similar conditions.
• Investigated sterilization effectiveness at specific pressures (25 MPa) and temperatures (35°C).

Main Results:

• Supercritical (SC) CO2 micro-bubble treatment achieved complete sterilization of Lactobacillus brevis and Saccharomyces cerevisiae.
• Gaseous (G) and liquid (LQ) CO2 treatments did not result in effective microbial sterilization.
• Optimal sterilization was observed with SC CO2 at 25 MPa and 35°C.

Conclusions:

• Supercritical CO2 micro-bubble technology is a highly effective method for sterilizing Lactobacillus brevis and Saccharomyces cerevisiae.
• SC CO2 treatment offers a superior alternative to G and LQ CO2 for microbial inactivation.
• The findings suggest potential applications of SC CO2 micro-bubble sterilization in food safety and preservation.