Structural relationships of sugars to taste

Area of Science:

• Carbohydrate Chemistry
• Sensory Science
• Molecular Biology

Background:

• Sugars and their analogues exhibit a range of taste profiles, including sweet, bitter, and combined bitter-sweet sensations.
• The co-occurrence of sweet and bitter tastes suggests an intrinsic association between these basic tastes within the same molecule.

Purpose of the Study:

• To investigate the relationship between the chemical structure of sugars and their taste properties.
• To map the specific regions of sugar molecules responsible for eliciting sweetness and bitterness.
• To understand how sugars interact with taste bud receptors.

Main Methods:

• Systematic chemical modification of sugars and their analogues at chiral centers.
• Analysis of taste profiles (sweetness and bitterness) of modified compounds.
• Application of hydrogen bond theories and spatial criteria to explain taste perception.

Main Results:

• Sugar molecules can be "polarized" on taste receptors, with distinct molecular ends interacting to produce sweetness and bitterness.
• The anomeric center in glucopyranose structures does not significantly influence sweetness.
• Sweetness and bitterness can mutually inhibit each other, necessitating corrections for comparative structural analysis.

Conclusions:

• The taste of sugars is intricately linked to their chemical structure and their "polarized" interaction with taste receptors.
• Hydrogen bonding and specific oxygen-oxygen interorbital spacings are crucial factors in determining sugar sweetness.
• Understanding these structure-taste relationships provides insights into molecular mechanisms of taste perception.