The behaviour of Escherichia coli and Pseudomonas aeruginosa in bottled mineral water

Michael Schalli; Sabine Platzer; Doris Haas; Franz F Reinthaler

doi:10.1016/j.heliyon.2023.e21634

The behaviour of Escherichia coli and Pseudomonas aeruginosa in bottled mineral water

Heliyon. 2023 Oct 30;9(11):e21634. doi: 10.1016/j.heliyon.2023.e21634. eCollection 2023 Nov.

Authors

Michael Schalli¹, Sabine Platzer¹, Doris Haas², Franz F Reinthaler¹

Affiliations

¹ Department for Water-Hygiene and Micro-Ecology, D&R Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, 8010, Graz, Austria.
² Applied Hygiene and Aerobiology, D&R Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, 8010, Graz, Austria.

Abstract

Microbial contamination of bottled water during the filling and capping procedure is a problem which should be avoided. The examination of the influence of carbon dioxide (CO₂) on bacterial growth of Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) in bottled mineral water was the aim of this study. Commercially available glass bottles with plastic screw caps filled with natural mineral water (without additional CO₂ "still" (StMW) and with CO₂ "sparkling" (SpMW) were obtained from a manufacturer in the province of Styria, Austria. The artificial contamination was performed in the lab by opening the bottle with subsequent addition of a bacterial solution with a defined number of bacteria. For each bacterial strain, 12 bottles were prepared. Samples (100 mL) were taken after a specific number of days, filtrated and placed on Endo Agar for cultivation. After incubation for 24 h bacterial colonies were counted. In this study CO₂ addition to bottled water reduced colony forming units of the two investigated bacterial strains over time.

Keywords: Carbon dioxide; Escherichia coli; Food contamination; Mineral water; Pseudomonas aeruginosa; Water supply.