Gustatory Psychophysical Clinic-Based Assessments
| Instrument | Function assessed | Substances used | Protocol | Advantages | Disadvantages |
|---|---|---|---|---|---|
| Whole mouth evaluation | |||||
| Taste sprays | Identification | Substances diluted in 100 mL distilled water: sweet (10g D-saccharose), sour (5g citric acid), salty (7.5g NaCl), bitter (0.025g quinine hydrochloride), and umami (4g MSU) | Patients open mouth for spray application and close mouth as they identify flavor. Patients receive 1 point for each correctly identified taste. The score is graded 0 to 5. | Indicates whether “suprathreshold” taste perception has been preserved, provides overall taste quality perception data, short time needed for testing, good reproducibility of results, long shelf life | Examiners cannot test individual parts of the oral cavityRequires clinician administration |
| “Sip and spit” tests | Identification | Patients imbibe flavors from cups or other vessels and then report on the detected flavor. | |||
| Regional evaluation | |||||
| Taste strips | Identification, threshold | 20 taste-impregnated filter-paper strips presented in randomized order with taste qualities in increasing concentrations: sweet (0.4, 0.2, 0.1, 0.05 g/mL sucrose), sour (0.3, 0.165, 0.09, 0.05 g/mL citric acid), salty (0.25, 0.1, 0.04, 0.016 g/mL NaCl), bitter (0.006, 0.0024, 0.0009, 0.0004 g/mL quinine hydrochloride), and umami (0.25, 0.1, 0.04, 0.016 g/mL MSG) | Patients identify the taste quality on a form. Patients receive 1 point for each correctly identified taste. The score is graded 0 to 20. An overall score ≤9 is considered hypogeusia. | Allows examiners to test each side of the tongue independently, provides basic data on detection threshold and intensity of flavor, short time needed for testing, good reproducibility of results, long shelf life | Certain areas of the tongue may be difficult to isolate or reach with strips or dropsRequires clinician administration |
Abbreviations: MSG, monosodium glutamate; MSU, monosodium urate; NaCl, sodium chloride.