Samples were taken from containers equipped with taps available to customers, water jugs and bottles, water additionally filtered by restaurants themselves, water flavoured with vegetables and taps in serving counters.
A total of 96 water samples were taken, of which 91% met the microbiological quality requirements and objectives for Domestic Water. Nine (9%) of the water samples were of poor microbiological quality.
The samples were tested for intestinal enterococci and Escherichia coli, as well as for coliform bacteria and the number of heterotrophic colonies (22 °C) to establish whether the samples met domestic water quality requirements. Flavoured drinking waters containing fruits, berries or vegetables, which naturally contain microbes from vegetables, were examined for intestinal enterococci and E. coli.
Twenty-six samples of flavoured waters were examined, of which five samples (19%) were of poor quality, due to intestinal enterococci. Twenty-two samples of water served in containers equipped with taps were examined, of which three samples (14%) were of poor quality due to coliform bacteria and high heterotrophic colony counts. Twenty-five samples of water served in jugs were examined, of which one (4%) was of poor quality due to intestinal enterococci. All the 25 samples taken from taps in serving counters and water filtered by restaurants themselves were of good quality. No E. coli bacteria were detected in any of the water samples.
− As a rule, the self-serve water in restaurants is of good quality. The poorest results were obtained for waters flavoured with vegetables by restaurants, one in five of which did not meet the quality requirements set for water in the distribution network, says food inspector Paula Saarijärvi from the City of Helsinki's environmental services.
In the flavoured waters, intestinal enterococci are likely to have entered the water from the outer surface of the vegetables. The presence of enterococci can be a sign of old faecal contamination, but they can also come from soil, for example. No intestinal enterococci were detected in the repeat samples.
The heterotrophic colony count, i.e. the number of bacteria, yeasts and moulds, was highest in the water containers equipped with taps.
Based on the results, some restaurants need guidance for washing vegetables used in flavoured waters and for better cleaning of water containers with taps.
