Table 1.
Concentrations (g/L) of sucrose, sodium chloride, caffeine, and citric acid used to determine recognition thresholds.
| Taste Quality | Reference Stimuli | Sample Concentration (g/L) a | ||||||
|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||
| Sweet | Sucrose | 1.6 × 10−1 | 4.0 × 10−1 | 1.02 | 2.56 | 6.4 | 16.0 | 40.0 |
| Salty | Sodium chloride | 6.25 × 10−2 | 1.25 × 10−2 | 2.5 × 10−1 | 5.0 × 10−1 | 1.0 | 2.0 | 4.0 |
| Bitter | Caffeine | 3.0 × 10−3 | 9.0 × 10−3 | 3.0 × 10−2 | 8.0 × 10−2 | 2.4 × 10−1 | 8.0 × 10−1 | 2.0 |
| Sour | Citric acid | 2.0 × 10−2 | 5.0 × 10−2 | 8.0 × 10−2 | 1.5 × 10−1 | 3.5 × 10−1 | 7.5 × 10−1 | 1.5 |
a The concentration series for sucrose, sodium chloride, and caffeine were prepared with successive 0.4 log dilution steps. The concentration series for citric acid were prepared with successive 0.3 log dilution steps. Reference chemical details: sucrose (Sigma Aldrich srl, Milano, Italy), sodium chloride (Sigma Aldrich srl, Milano, Italy), caffeine (Sigma Aldrich srl, Milano, Italy), and citric acid (Sigma Aldrich srl, Milano, Italy).