High intensity light pulses to reduce microbial load in fresh cheese

Area of Science:

• Food Science
• Microbiology
• Food Preservation Technology

Background:

• Microbial contamination poses a significant challenge to the shelf life and safety of perishable foods like mozzarella cheese.
• Traditional preservation methods may impact cheese quality or be insufficient against certain spoilage microorganisms.

Purpose of the Study:

• To evaluate the efficacy of High Intensity Light Pulses (HILP) treatment for microbial inactivation on mozzarella cheese.
• To assess the impact of HILP on key spoilage bacteria, specifically Pseudomonas spp. and Enterobacteriaceae, during refrigerated storage.

Main Methods:

• In-vitro susceptibility testing of Pseudomonas fluorescens and Enterobacteriaceae to HILP.
• Application of HILP to inoculated mozzarella cheese samples.
• Storage of treated and untreated (Control) samples at 10 °C for 2 weeks with microbial monitoring.

Main Results:

• HILP demonstrated significant microbial inactivation in liquid media within 2 seconds.
• A reduction of approximately 1 log cycle in microbial load was observed on inoculated mozzarella cheese.
• HILP-treated samples maintained Pseudomonas spp. below the microbiological acceptability limit (10^6 cfu/g) throughout the 2-week storage period.

Conclusions:

• High Intensity Light Pulses (HILP) treatment shows significant potential for reducing microbial contamination on mozzarella cheese.
• HILP effectively controls microbial growth, suggesting it as a promising decontamination method for extending the shelf life of mozzarella.
• This technology offers a novel approach to enhance the microbiological safety of surface-contaminated cheese products.