Effect of gas hydrate formers on microorganisms

Area of Science:

• Food microbiology
• Chemical engineering
• Industrial microbiology

Background:

• Microbial contamination poses risks in the food industry.
• Aerosol propellants can potentially impact microbial viability.
• Understanding the antimicrobial effects of gas hydrate formers is crucial for food safety.

Purpose of the Study:

• To evaluate the antimicrobial efficacy of three gas hydrate formers: propane, dichlorodifluoromethane (f-12), and 1,1-difluoro-1-chloroethane (f-142b).
• To compare the toxicity of these compounds in both vapor and liquid states.
• To identify microorganisms resistant to these agents.

Main Methods:

• Incubation of food-relevant bacteria, yeasts, and molds in aerosol cans with a broth medium and gas hydrate formers.
• Testing at low (vapor), intermediate, and high (liquid) concentrations.
• Continuous agitation for 48 hours at 21°C.
• Microbial enumeration using plate counts.

Main Results:

• Propane exhibited higher toxicity in the vapor state compared to f-12 and f-142b.
• Gas hydrate formers were substantially more toxic in the liquid state than in the vapor state.
• Except for sporulated Bacillus cereus, all tested microorganisms showed significant population reduction in the presence of liquid f-12 or f-142b.

Conclusions:

• Gas hydrate formers, particularly in liquid form, possess significant antimicrobial activity against common food microorganisms.
• The state (vapor vs. liquid) and type of gas hydrate former influence antimicrobial efficacy.
• Further research may explore applications in food preservation or sterilization processes.