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Taste Exam: A Brief and Validated Test
Published on: August 17, 2018
A new specific ageusia: some humans cannot taste L-glutamate
O Lugaz1, A-M Pillias, A Faurion
1Laboratoire de Neurobiologie Sensorielle, 1 avenue des Olympiades, F-91744 Massy cedex, France.
Chemical Senses
|February 13, 2002
Summary
A new specific ageusia for monosodium L-glutamate (MSG) was identified. Researchers found that some individuals cannot distinguish MSG from salt (NaCl), indicating a specific taste deficiency for L-glutamate.
Area of Science:
- Sensory science
- Human taste perception
- Neuroscience
Background:
- Monosodium L-glutamate (MSG) is a widely used flavor enhancer.
- Individual differences in taste perception are well-documented.
- Specific ageusia (loss of taste) for certain compounds can occur.
Purpose of the Study:
- To investigate specific ageusia for monosodium L-glutamate (MSG) in human subjects.
- To differentiate between tasters, hypotasters, and non-tasters of MSG.
- To characterize the nature of taste perception differences for MSG and NaCl.
Main Methods:
- Utilized up-and-down procedures to determine taste thresholds and suprathreshold sensitivity for MSG and NaCl.
- Employed time-intensity (TI) perception profiles to analyze taste perception over time.
- Conducted a discrimination task using triangular presentations to assess stimulus differentiation.
Main Results:
- 73% of subjects showed specific sensitivity to MSG over NaCl.
- 27% of subjects were classified as putative hypotasters, with no significant difference in MSG and NaCl sensitivity.
- Time-intensity profiles revealed significant differences in 81% of tasters.
- A subset of subjects (3.5%) could not discriminate between MSG and NaCl, suggesting specific ageusia for MSG.
Conclusions:
- A specific ageusia for monosodium L-glutamate (MSG) exists in a small percentage of the human population.
- Taste perception differences for MSG and NaCl are complex and can be revealed by various psychophysical methods.
- Further research is needed to understand the genetic and physiological basis of MSG taste perception and specific ageusia.
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