World Journal of Agricultural Research. 2023, 11(2), 44-53
DOI: 10.12691/WJAR-11-2-2
Original Research

Identification and Description of Culturable Airborne Bacteria Suspended in Aerosols from the Milking Area in Two Dairy Farms in Puerto Rico by Using MALDI-TOF MS

J. J. Dragoni-Rosado1, , H. M. Ramirez-Ortiz1, A. González-Mederos1 and A. E. Pérez-Matos2

1Department of Science and Technology, Inter American University of Puerto Rico, San Germán, Puerto Rico

2Biotechnology and Agrobiotechnology Research and Learning Center, Department of Natural Sciences, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico

Pub. Date: May 30, 2023

Cite this paper

J. J. Dragoni-Rosado, H. M. Ramirez-Ortiz, A. González-Mederos and A. E. Pérez-Matos. Identification and Description of Culturable Airborne Bacteria Suspended in Aerosols from the Milking Area in Two Dairy Farms in Puerto Rico by Using MALDI-TOF MS. World Journal of Agricultural Research. 2023; 11(2):44-53. doi: 10.12691/WJAR-11-2-2


Due to its nutritional value and physicochemical characteristics, milk is susceptible to detrimental and pathogenic microorganisms. Therefore, the dairy industry needs to control the factors that pose risks to the safety and quality of the product. Thus, a microbiological analysis of the air was carried out in the milking area of two dairy farms in Puerto Rico. Triplicate air samples were collected from May to September 2021. The results showed that farm B had higher bacteria concentrations in most months. Sixty-three genera of bacteria were identified among all the samples collected from both farms using MALDI-TOF MS. Additionally, several important sanitary bacteria were detected in the samples, albeit at a low frequency. In conclusion, the results of this study demonstrate that the concentration of microorganisms in the air of milking areas can be influenced by different factors, such as the location of the farm, as well as temperature and relative humidity. Furthermore, MALDI-TOF MS proved to be a helpful and fast technique for identifying the isolated bacteria in the samples.


milk, food microbiology, environmental microbiology, milking area, environment


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