Reduction of Microorganisms on Beef Surfaces Utilizing Electricity.

Area of Science:

• Food Science
• Microbiology
• Food Safety Engineering

Background:

• Bacterial contamination on beef surfaces poses a significant food safety risk.
• Traditional methods for microbial reduction may not always be sufficient.
• Exploring novel decontamination technologies is crucial for the food industry.

Purpose of the Study:

• To investigate the efficacy of electrical stimulation in reducing bacterial loads on beef steaks.
• To determine the impact of different electrical current types, pulse frequencies, and voltage levels on microbial reduction.
• To assess the influence of pre-treatment with sterile deionized water on the effectiveness of electrical stimulation.

Main Methods:

• Top round beef steaks were subjected to various electrical stimulation parameters, including continuous electrical current, pulsed electrical current, and different voltage levels.
• Bacterial populations, including aerobic bacteria, total coliforms, and Salmonella Typhimurium, were enumerated before and after treatment.
• A pre-treatment with sterile deionized water was applied to some samples before electrical stimulation.

Main Results:

• Electrical stimulation (620 V, 20-60 s) significantly decreased coliform bacteria counts by an average of 81%.
• Pre-treatment with sterile deionized water enhanced the reduction of coliform counts.
• Pulsed electrical current (400 V/2.5 cm) and high voltage (1200 V/2.5 cm) significantly reduced Salmonella Typhimurium counts, with an 82% reduction observed at 1200 V/2.5 cm.

Conclusions:

• Electrical stimulation is an effective method for reducing aerobic bacteria, total coliforms, and Salmonella Typhimurium on beef steak surfaces.
• Optimizing electrical stimulation parameters, such as voltage and pulse application, can enhance microbial decontamination.
• This technology presents a viable non-thermal processing method for improving the microbiological safety of beef products.