Table 1.

Taste qualities and concentration series for the taste solution test

Taste quality	No.1	No.2	No.3	No.4	No.5
Sweet (Sucrose)	0.003	0.025	0.1	0.2	0.8
Sour (Tartaric acid)	0.003	0.0125	0.05	0.1	0.2
Salty (NaCl)	0.0002 0.0001∗ 0.00004∗ 0.00002∗	0.002	0.02	0.04	0.08
Bitter (Caffeine)	0.00001	0.0002	0.001	0.005	0.04

The values are expressed as g/ml. The lower concentrations than 0.0002 g/ml of NaCl were presented with ∗ in the table.