Portable Commercial Equipment Using Electromagnetic Pulse Fields: Effect on Water and Milk Microbiological Safety

Introduction: Ensuring the microbiological safety of food and beverages is essential for public health. Traditional pasteurization processes (PP) are widely used for sterilization; however, they may alter the sensory qualities of products. As an alternative, pulsed electric fields (PEF) have emerged as a non-thermal sterilization technique. Methods: This study evaluated the effectiveness of a commercial PEF device in reducing microbial loads in milk and water inoculated with several pathogens: Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) and Gram-negative bacteria (Salmonella Typhimurium, Escherichia coli, and Pseudomonas aeruginosa). The device (4.44 V/cm) applied variable-frequency pulses (0–250 kHz) to fluids flowing through a polyethylene tube. Results: Traditional pasteurization significantly reduced bacterial counts. For certain strains of S. aureus in milk and saline solution, PEF achieved reductions comparable to those obtained with PP. However, L. monocytogenes and some Gram-negative bacteria showed lower sensitivity and variability in their responses across different species and strains. Factors such as medium composition and electrical conductivity may influence treatment effectiveness. Discussion: The portable PEF device demonstrated potential as a non-thermal alternative for microbial reduction, particularly in water. Nonetheless, further research is needed to optimize the technology, evaluate a broader range of bacterial species, and determine its effects on the sensory and nutritional characteristics of food and beverages. Conclusion: This study underscores the potential of portable PEF devices as a practical nonthermal method for microbial reduction compared to traditional pasteurization, especially when applied to water. However, additional research is necessary to improve its efficiency, expand the microbial spectrum evaluated, and assess its impact on product quality. These findings highlight the promising role of PEF in enhancing microbiological safety within the food and beverage industries.