Rapid sample processing for detection of food-borne pathogens via cross-flow microfiltration

Area of Science:

• Food Science
• Microbiology
• Analytical Chemistry

Background:

• Rapid and sensitive detection of bacterial pathogens in food is crucial for public health.
• Current preanalytical methods for pathogen detection can be time-consuming and labor-intensive.
• There is a need for efficient sample preparation techniques to improve pathogen detection limits.

Purpose of the Study:

• To develop and validate an automated approach for rapid concentration and recovery of bacterial cells from chicken homogenates.
• To establish a preanalytical step that enhances the sensitivity of pathogen detection.
• To reduce the time required for sample preparation in food safety testing.

Main Methods:

• Biochemical pretreatment and prefiltration of food samples.
• Development of an automated cell concentration instrument utilizing cross-flow microfiltration with a 0.2 μm polysulfone hollow-fiber membrane.
• Circulation of aqueous chicken homogenate samples within the cross-flow system.

Main Results:

• Achieved 500- to 1,000-fold concentration of Salmonella enterica serovar Enteritidis and natural microbiota.
• Obtained 70% recovery of viable cells within 35 to 45 minutes.
• Enabled quantification of microorganisms at 10 CFU/ml in homogenates or 10(2) CFU/g chicken.
• Demonstrated membrane reusability for at least 15 cycles through effective cleaning and sterilization protocols.

Conclusions:

• The developed automated approach significantly enhances bacterial cell concentration from chicken samples.
• This method provides a rapid and efficient preanalytical step for improved pathogen detection in food.
• The system addresses the food industry's need for faster pathogen detection, potentially within a 6-hour timeframe.