Reduction of Salmonella by two commercial egg white pasteurization methods

Area of Science:

• Food Science
• Microbiology
• Food Safety

Background:

• Commercial egg white pasteurization is crucial for eliminating foodborne pathogens like Salmonella.
• Existing methods, including Armour and Standard Brands, utilize hydrogen peroxide and specific heating regimens.
• Optimizing pasteurization parameters is essential for ensuring microbial safety without compromising egg white quality.

Purpose of the Study:

• To evaluate the efficacy of two commercial egg white pasteurization methods (Armour and Standard Brands) against Salmonella.
• To determine the impact of pH, processing temperatures, and preheating on Salmonella reduction.
• To provide data for establishing optimal processing conditions for hydrogen peroxide-based egg white pasteurization.

Main Methods:

• A benchtop pasteurization system was developed to simulate commercial processes.
• Salmonella reduction was assessed across various pH levels (8.2, 8.6, 9.0) and temperatures (51.7-55.8°C).
• D-values were calculated to quantify microbial inactivation under different conditions, comparing methods with and without preheating.

Main Results:

• The Standard Brands method demonstrated significantly greater Salmonella log reduction than the Armour method across most tested conditions (P < 0.05).
• Higher pH (9.0) generally resulted in enhanced microbial reduction, particularly in older, off-line processing simulations.
• Preheating steps did not significantly contribute to Salmonella reduction in either pasteurization method.

Conclusions:

• The Standard Brands method offers superior Salmonella inactivation compared to the Armour method under similar processing conditions.
• Egg white pH is a critical factor influencing pasteurization efficacy, with higher pH yielding better results.
• Recommendations for minimum processing conditions for hydrogen peroxide-based egg white pasteurization can be derived from these findings to enhance food safety.