Drinking water was analysed for a comparison of two Swedish municipalities using raw water of different origins, surface water and ground water. Sensory assessments for flavour attributes (triangle test and quantitative- descriptive analysis) were performed, along with chemical and microbiological tests according to Swedish drinking water standards. In addition, the commercial water Evian was included in the analyses as a bottled-water benchmark for sensory and chemical comparison. The results from the triangle test showed significant sensory differences between tap water from surface water and groundwater, and in samples collected at different points - at the waterworks and at points downstream in the distribution system. The descriptive analysis showed differences in the perception of the attributes bitter, mineral and off-taste. The perceived differences are in line with earlier studies identifying inorganic ions as being responsible for the taste sensations. The chemical analyses showed major differences between the two types of tap water, with higher mineral content and higher alkalinity in the groundwater compared to the surface water. The microbiological analyses did not show any measurable differences in any of the samples.
Mårtensson et al. (Wed,) studied this question.