Taste Function in Healthy Taiwanese Adults

Normative data on the subjective gustatory function of Chinese adults

PURPOSE

the study aims to assess the gustatory function of healthy Chinese adults with the whole-mouth test based on five basic tastants, including umami taste.

METHODS

the study recruited 464 participants reporting a normal sense of smell/taste (227 females and 237 males with an age range of 19-65 years). A drop (approximately 0.1 mL) of liquid tastant was applied on the anterior third of the extended tongue of each subject. The taste solutions involved 5 tastants (sour, sweet, salty, umami, and bitter) and 7 concentrations. Taste perception scores and recognition scores of the five basic tastants were obtained with this whole-mouth taste method.

RESULTS

total taste score of recognition showed a significant negative correlation with age. The elder group (51-65 years) had the lowest scores. The 10th percentile of total taste score of recognition in the group of 36 to 50 years was used to distinguish normogeusic subjects from hypogeusic subjects. The perception scores and recognition scores of females were higher than those of males. The perception and recognition thresholds of salty, umami, and bitter for females were lower than those for males. Total taste score of recognition for non-smokers was significantly higher than that of smokers. The whole-mouth method showed a high test-retest reliability with an intra-class correlation coefficient (ICC) from 0.774 to 0.833.

CONCLUSION

this whole-mouth method is simple and time-saving and can be easily adjusted to obtain reliable data. The gustatory function was significantly negatively correlated with age. Females were more sensitive to the sour, salty, umami and bitter tastes than males. The gustatory function of non-smokers was more sensitive.

[Reliability of whole-mouth taste test in assessment of gustatory function in healthy adults]

Objective:The purpose of this study was to evaluate the test-retest reliability of gustatory function using whole-mouth taste tests in healthy adults. Methods:Fifty healthy subjects were tested by whole-mouth taste test. The taste test involved 5 tastants（sour, sweet, salty, umami and bitter） and 7 concentrations. The tastant solutions were administered in a pseudo-random order starting with the lowest concentration. Record the perception and recognition scores of each tastant separately. The same operator performed test again by the same method two weeks later. The relative reliability and absolute reliability of the whole-mouth taste test were evaluated with intraclass correlation coefficient（ICC） and standard errors of measurement（SEM）, SEM% respectively. Results:The intraclass correlation coefficient of the perception scores of the sour, sweet, salty, umami and bitter in healthy subjects were from 0.753 to 0.819, ICC values of recognition score range from 0.751 to 0.828. In terms of absolute reliability, the SEM and SEM% values of perception scores were 0.329-0.463 and 6.60%-9.07% respectively; SEM of recognition scores were 0.425-0.581 and SEM%=9.09%-14.66%. Conclusion:The whole-mouth taste test could be a reliable tool for gustatory function test with good test-retest reliability in healthy adults.

A Pilot Study of the Waterless Empirical Taste Test

OBJECTIVES

This study was performed to test the clinical applicability of a new taste test-the waterless empirical taste test (WETT).

METHODS

Sixty healthy volunteers and 20 patients with oral cancer were enrolled. They all received the conventional solution-based whole-mouth suprathreshold taste test (WMTT), which contained sucrose, citric acid, sodium chloride, and caffeine solutions for tastants, along with the WETT. The WETT used plastic strips to deliver tastants. The strip was embedded with sucrose, citric acid, sodium chloride, caffeine, or monosodium glutamate taste enhancer in 4 different concentrations. Each strip was tested twice. Thirty of the healthy volunteers received the WETT again to measure a retest reliability. Case-control matching by age and gender was used to compare the scores of WMTT and WETT between 13 healthy volunteers and 13 patients with oral cancer.

RESULTS

The correlation was not high between the WMTT and WETT (r < 0.7) whether in the healthy volunteers or in patients with oral cancer. In terms of retest reliability of the WETT, the mean total score was 24.9 ± 7.3 for the first test and 25.8 ± 8.4 for the second test. The intraclass correlation coefficient was 0.85 (P < .001). When case-control matching was performed, the WMTT scores were not significantly different between 13 healthy volunteers and 13 patients with oral cancer (P = .266), but the WETT scores were significantly lower in patients with oral cancer (P = .017).

CONCLUSION

This study showed that the results of the WETT were not highly correlated with those of the WMTT. However, its retest reliability was high, and its results were significantly different between the healthy volunteers and the patients with oral cancer.

Prognosis of olfactory and gustatory dysfunctions in COVID-19 patients: A case series

Although most COVID‐19 patients feel their olfactory function returns to normal, the smell test demonstrates that a mild impairment of the olfactory function may have remained. Therefore, their olfactory function should be evaluated by a smell test.