Preserving fish quality through intense pulsed light: microbial inactivation and ATP degradation control

Area of Science:

• Food Science
• Microbiology
• Biotechnology

Background:

• Maintaining fish freshness and safety is crucial for public health and the food industry.
• Intense pulsed light (IPL) is an emerging non-thermal technology for microbial inactivation in food.
• Assessing fish quality degradation during storage is essential for shelf-life determination.

Purpose of the Study:

• To evaluate the efficacy of intense pulsed light (IPL) in reducing microbial load on fish.
• To investigate the impact of IPL on fish freshness indicators, specifically hypoxanthine accumulation.
• To determine the optimal IPL energy fluences for balancing microbial inactivation and preserving fish quality.

Main Methods:

• Six types of fish were treated with IPL at energy fluences ranging from 3.6 to 28.4 J/cm².
• Microbial inactivation levels were quantified post-treatment.
• Fish freshness was assessed by measuring K₁ value and hypoxanthine ratio throughout the storage period.
• The effect of different IPL energy levels on ATP degradation and hypoxanthine accumulation was analyzed.

Main Results:

• IPL treatment achieved maximum microbial inactivation levels between 1.23 and 1.85 log across the six fish types.
• IPL significantly reduced the rate of hypoxanthine accumulation in all treated fish, with notable effects observed at specific energy fluences (e.g., 74.9% reduction in red seabream at 17.1 J/cm² on day 10).
• Excessively high IPL energy fluences were found to accelerate fish freshness deterioration during storage.

Conclusions:

• IPL is effective in reducing microbial load and retarding spoilage indicators like hypoxanthine accumulation in fish.
• Optimizing IPL energy is critical to maximize microbial inactivation while minimizing adverse effects on fish freshness.
• Further research is needed to establish precise IPL treatment parameters for different fish species to ensure both safety and quality.