Microbiological evaluation of bottled non-carbonated ("still") water from domestic brands in Greece.

The microbiological quality of 1,527 samples of bottled non-carbonated ('still') mineral water, purchased from retail outlets and derived from 10 manufacturing companies in Greece, was investigated during the period 1995-2003. Applying the membrane filter technique, the aliquots of water samples (250 ml) were analyzed for the presence and enumeration of total coliforms, Escherichia coli, Enterococcus spp. and Pseudomonas aeruginosa. Also, aerobic bacteria were counted as Heterotrophic Plate Count (HPC) ml(-1) at 22 and 37 degrees C. Positive samples for the parameters tested varied significantly among brands with an overall percentage of 13.95% bottled water samples noncompliant with the Greek water regulation. Microorganisms isolated from the samples tested were identified as species of Pseudomonas, Aeromonas, Pasteurella, Citrobacter, Flavobacterium, Providencia and Enterococcus. The most frequent isolated microorganism during the period of the study was P. aeruginosa. Generally, bacterial load of the samples tested ranged in low levels. The purpose of the current study was to evaluate the microbiological quality of the bottled water provided by domestic brands in the Greek market during the period 1995-2003.