The pH-value describes the acid content of a fluid. It can vary between 0 (strongly acidic) and 14 (strongly alkaline/basic). With a value of 7 the solution is described as neutral. Carbonated mineral and health waters are on the slightly acidic side. Non-carbonated waters are usually neutral.
Gerolsteiner Sparkling and Gerolsteiner Medium have a pH-value of 5.9 to 6.0. With a pH-value of 6.9, Gerolsteiner Naturell is almost neutral.
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