Detection of listeria, e. coli and salmonella in berries by rapid microbiological methods (redox potential measurement + real-time PCR

Abstract

Raw or low processed fruits are popular and delicious. Due to the low level of processing, the risk for bacterial contamination is usually higher than for other kinds of foods. The detection of pathogenic bacteria is a fundamental objective of food microbiology ensuring food safety. Due to the fact that traditional methods for detecting bacteria or other pathogens are usually time-consuming, the need for faster detection is high. In this study we examined the possibility of the application of the redox potential based measurement method for the detection of Listeria monocytogenes, Salmonella and E. coli in berries. Due to the fact that the acids and enzymes can disturb the redox potential measurement, we used the whole fruit when we constructed the calibration curves of the bacteria. In case of detection of Listeria monocytogenes and Salmonella the further confirmation was done by real-time PCR. All samples were examined by the standard methods, too.