The potential of pulsed electromagnetic field-generated shock waves for reducing microbial load and improving homogenization in raw milk

Abstract

Milk is a highly nutritious food essential for human consumption. However, traditional thermal processing methods can reduce its nutritional value and cause unwanted changes. The use of shock waves produced by pulsed electromagnetic fields (PEMFs) has been explored as a means to reduce pathogenic microorganisms. The effect of shock wave treatment on microbial load and particle distribution in packaged fresh cow's milk was investigated. Additionally, the impact of shock wave treatment on Salmonella enterica counts in a bacterial suspension of phosphate-buffered saline (PBS) was evaluated, as this bacterium is a significant milkborne pathogen. Treatment with 1000 impulses from an electromagnetic shock wave generator resulted in a 0.7-log reduction in the total bacterial count of milk. In a separate experiment, a 300-impulse shock wave treatment applied to a Salmonella enterica suspension achieved a 3-log reduction in bacterial counts. Furthermore, shock wave treatment resulted in a decrease in milk particle size compared to untreated milk. Notably, the volume of milk used in this study aligns with commercially available packaged products, enhancing the experiment's industrial relevance. The use of PEMF to generate shock waves could provide a novel approach for future studies focused on reducing the microbial load of milk and improving its homogenization.

Keywords

• Pasteurization
• Non-thermal processing
• Salmonella enterica
• Cavitation
• Particle size