Suppression of sweetness: evidence for central mechanism for suppression of sweetness from sucrose by citric acid

TY - JOUR

T1 - Suppression of sweetness

T2 - evidence for central mechanism for suppression of sweetness from sucrose by citric acid

AU - Junge, Jonas Yde

AU - Andersen, Glenn Hjorth

AU - Kidmose, Ulla

PY - 2023/9

Y1 - 2023/9

N2 - The underlying mechanisms of taste interactions in humans are not well understood, and three mechanisms have been proposed, namely a chemical interaction, a peripheral physiological, and a central mechanism. In the present study, it was investigated which of these mechanisms causes the suppression of sweetness by citric acid. This was investigated using a split-tongue gustometer that can stimulate the two sides of the tongue with different stimuli simultaneously, enabling a comparison of sucrose and citric acid presented either separately on each side of the tongue simultaneously or in a mixture on one side. Two studies were conducted using low (Study 1; n = 50) and high (Study 2: n = 59) concentrations of sucrose (2.5% (w/w) and 10% (w/w), respectively), and citric acid (0.14% (w/w) and 0.18% (w/w), respectively). In neither of the studies was there a significant difference in sweetness intensity ratings between the two conditions where sucrose and citric acid were presented either separately or in a mixture form. However, both showed significantly lower sweetness ratings than without citric acid indicating suppression of the sweetness of sucrose from citric acid. This provides strong evidence for a central mechanism for the suppression of the sweetness of sucrose by citric acid. This mechanism seems to be equal in high and low concentrations of both sucrose and citric acid.

AB - The underlying mechanisms of taste interactions in humans are not well understood, and three mechanisms have been proposed, namely a chemical interaction, a peripheral physiological, and a central mechanism. In the present study, it was investigated which of these mechanisms causes the suppression of sweetness by citric acid. This was investigated using a split-tongue gustometer that can stimulate the two sides of the tongue with different stimuli simultaneously, enabling a comparison of sucrose and citric acid presented either separately on each side of the tongue simultaneously or in a mixture on one side. Two studies were conducted using low (Study 1; n = 50) and high (Study 2: n = 59) concentrations of sucrose (2.5% (w/w) and 10% (w/w), respectively), and citric acid (0.14% (w/w) and 0.18% (w/w), respectively). In neither of the studies was there a significant difference in sweetness intensity ratings between the two conditions where sucrose and citric acid were presented either separately or in a mixture form. However, both showed significantly lower sweetness ratings than without citric acid indicating suppression of the sweetness of sucrose from citric acid. This provides strong evidence for a central mechanism for the suppression of the sweetness of sucrose by citric acid. This mechanism seems to be equal in high and low concentrations of both sucrose and citric acid.

KW - binary taste interactions

KW - half tongue study

KW - mixture suppression

KW - taste perception

KW - taste primaries

KW - Tongue

KW - Sucrose/pharmacology

KW - Citric Acid/pharmacology

KW - Humans

UR - http://www.scopus.com/inward/record.url?scp=85172424700&partnerID=8YFLogxK

U2 - 10.1093/chemse/bjad036

DO - 10.1093/chemse/bjad036

M3 - Journal article

C2 - 37668445

SN - 0379-864X

VL - 48

JO - Chemical Senses

JF - Chemical Senses

M1 - bjad036

ER -