Application of MALDI-TOF-MS in the surveillance of microbial diversity in butter production: a case study of Polish dairy

The primary objective of the study was to adapt and evaluate the utility of the rapid MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry) identification method for comprehensive microbiological safety monitoring across the farm-to-butter chain. The research was conducted as a detailed case analysis within a selected Polish dairy facility, focusing on the microbial profiling from the milking to the final product stage. The application of this method enabled comprehensive microbiota profiling of 400 milk samples, along with 63 additional samples from nine stages of the butter production process, resulting in the identification of 146 different cultivable microorganisms. The microbiota of fresh bovine milk was primarily composed of bacteria from the genera Staphylococcus, Corynebacterium, Aerococcus, and the species Bacillus licheniformis. The highest microbial diversity was observed in samples taken from tankers transporting milk to the dairy. Pasteurization effectively reduced the total number of microorganisms, but did not completely eliminate spore-forming or psychrophilic bacteria. The results emphasize the need to maintain a high level of hygiene at every stage of production in order to ensure microbiological safety and quality of dairy products.