Effect of Water TDS Control on the Sensory Consistency of Coffee: A Comparative Analysis of Relative Influence of Mineral Composition Differences across Water Sources

To establish an effective water quality management strategy for franchise coffee brands, this study examined the relative influence of water-source mineral composition and total dissolved solids (TDS) on sensory consistency. Raw water from three domestic locations was adjusted to two TDS levels (95 ppm and 45 ppm) using a reverse osmosis (RO)-based water purification system. Sensory differences were evaluated through triangle tests and attribute difference tests; triangle test outcomes were interpreted based on ISO 4120 significance criteria, and attribute difference test data were analyzed using two-way and one-way ANOVA. Triangle test results showed no significant sensory differences among the three water sources at 95 ppm (p>0.05). At 45 ppm, a significant difference was detected in one sample pair; however, this difference was attributed to an 8.0 ppm deviation in measured TDS rather than differences in mineral composition. In attribute difference tests, the water-source factor showed no significant main effects across all 11 sensory attributes, whereas the TDS factor exhibited significant effects on sweetness, acidity, body, unclean mouthfeel, and aftertaste (p