Modeling the UV-C Inactivation Kinetics and Determination of Fluence Required for Incremental Inactivation of...

Area of Science:

• Microbiology
• Photochemistry
• Food Safety Engineering

Background:

• Cronobacter spp. are opportunistic foodborne pathogens.
• UV-C irradiation is a promising disinfection technology.
• Understanding UV-C inactivation kinetics is crucial for effective microbial control.

Purpose of the Study:

• To model the UV-C inactivation kinetics of Cronobacter spp.
• To determine the UV-C fluences required for incremental inactivation.
• To establish a foundation for designing efficient UV-based disinfection systems.

Main Methods:

• 13 strains of Cronobacter spp. were suspended in PBS.
• Samples were treated with UV-C doses ranging from 0 to 10 mJ cm⁻².
• Log reduction was determined by plate counts and fitted to mathematical models, including Weibull+tail.

Main Results:

• A UV-C dose of 10 mJ cm⁻² achieved 3.66 to 5.04 log CFU mL⁻¹ inactivation.
• The Weibull+tail model accurately described survival behavior (97.17–99.71% correlation).
• D10-values ranged from 3.53 to 5.50 mJ cm⁻², with >6.57 mJ cm⁻² needed for 4-log reduction.

Conclusions:

• UV-C dose-response data provides critical insights into Cronobacter spp. inactivation.
• The Weibull+tail model effectively predicts microbial inactivation.
• This research supports the development of optimized UV-C disinfection strategies for food safety.