Sensory analysis of four medical spa spring waters containing various mineral concentrations

Medical spa spring waters (MSSWs) have been extensively used as adjunctive treatments for various skin conditions to provide skin comfort. We carried out a double-blind study to compare the sensory profile of four MSSWs with increasing mineral content.

A panel of 36 women, trained to perform comparative sensory analysis, applied in pairs four MSSWs with mineral contents of 0.2, 0.45, 5, and 11 g/L on the right and left cheeks. At baseline, 5 min, and 10 min after the applications, the subjects evaluated each water for the following factors using a computerized analog scale: freshness, mild stinging, softness, suppleness, and comfort of the skin.

After 5 min, all four waters induced a sensation of freshness, irrespective of their mineral concentration. A mild stinging was also perceived with all four waters, with a magnitude that was dependent on the mineral density. After 10 min, softness, suppleness, and skin comfort were the prominent features induced by the waters, but the lower the mineral content, the greater these perceptions. Statistically significant differences were demonstrated between the 0.2 g/L group and the 5 and 11 g/L groups for stinging (P = 0.0001), softness and suppleness (P < 0.05), and skin comfort (P = 0.006) after 10 min.

Our results indicate that the sensory effects provided by MSSWs when topically applied depend on their mineral concentration.