# The Applications of MALDI-TOF MS in the Diagnosis of Microbiological Food Contamination
###### Abstract  
Microbiological contamination of food remains a critical global public health concern, contributing to millions of foodborne illness cases each year. Traditional diagnostic methods, particularly culture-based techniques, have been widely employed but are often limited by low sensitivity, insufficient specificity, and lengthy turnaround times. Recent advances in molecular biology, biosensor technology, and analytical chemistry have enabled the development of more rapid and precise diagnostic tools. Among these, Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) has emerged as a transformative method for microbial identification. This review provides a comprehensive overview of the current applications of MALDI-TOF MS in the diagnosis of microbiological contamination in food. The method offers rapid, accurate, and cost-effective identification of microorganisms and is increasingly used in food safety laboratories for the detection of foodborne pathogens, ensuring the safety and quality of food products. We highlight the fundamental principles of MALDI-TOF MS, discuss its methodologies, and examine its advantages, limitations, and future prospects in food microbiology and quality assurance. MALDI-TOF MS; matrix-assisted laser desorption/ionization; microbial identification; foodborne pathogens; food microbiology; food safety; spoilage organisms; traceability +
Footnote †: journal: Applied sciences  
Safety Authority (EFSA), and the U.S. Food and Drug Administration (FDA). Traditional microbiological methods, including culture-based identification, biochemical profiling, and serotyping, are often time-consuming, labor-intensive, and limited in resolution, particularly when distinguishing closely related species or subspecies [2; 10; 11; 12; 13]. In recent decades, the introduction of molecular diagnostics--including polymerase chain reaction (PCR), quantitative PCR (qPCR), next-generation sequencing (NGS), and whole genome sequencing (WGS)--has significantly improved the sensitivity and specificity of microbial detection. However, these techniques have limitations: they often require skilled personnel, costly reagents, extensive sample preparation, and, in some cases, cannot differentiate between viable and non-viable cells [14; 15; 16; 17; 18; 19; 20]. Within this evolving landscape, MALDI-TOF MS has emerged as a powerful tool, particularly in clinical microbiology, and is now rapidly gaining traction in food microbiology. MALDI-TOF MS enables the rapid identification of microorganisms based on the unique mass spectral fingerprints of their ribosomal proteins. It combines speed, low per-sample cost, and high-throughput capabilities, making it particularly attractive for routine monitoring in food safety laboratories, industrial quality assurance settings, and public health surveillance programs [21; 22; 23; 24]. The principle of MALDI-TOF MS lies in the ionization of microbial peptides followed by their separation based on mass-to-charge (m/z) ratios. The resulting spectra are then matched against reference libraries to generate accurate identifications of microorganisms, often to the species level. This approach eliminates the need for time-consuming biochemical tests or DNA sequencing for many routine analyses and provides results within minutes, once a culture is available [25; 26; 27; 28; 15]. Beyond simple microbial identification, the versatility of MALDI-TOF MS extends to its applications in strain-level typing, detection of antimicrobial resistance, monitoring of fermentation processes, authentication of food origin, and traceability of contamination sources. These advanced capabilities make MALDI-TOF MS a valuable tool, not only for pathogen diagnostics, but also for broader microbial ecosystem surveillance and quality assurance [25; 29; 30; 31; 32; 33].