Taste Perception of Branched Maltooligosaccharides

Area of Science:

• Food Science
• Carbohydrate Chemistry
• Sensory Science

Background:

• Oral processing of starch yields linear and branched maltooligosaccharides (MOS).
• The taste perception of MOS, particularly the role of branching and polymerization degree, remains incompletely understood.
• Distinguishing between sweet and putative
• starchy
• receptors for carbohydrates is an active area of research.

Purpose of the Study:

• To investigate the impact of branching and degree of polymerization (DP) on the taste detection of maltooligosaccharides (MOS).
• To determine the taste receptor mechanism responsible for MOS detection, specifically differentiating between sweet and
• starchy
• receptors.

Main Methods:

• Enzymatic preparation of branched MOS from waxy corn starch with varying DPs (6, 10, 18).
• Characterization using reducing-end assays, MALDI-TOF MS, β-amylase hydrolysis, and GC-MS linkage analysis to confirm structure and branching (α-1,6).
• Sensory evaluation using triangle tests with human participants, assessing MOS and maltose (control) at 75 mM, with and without the sweet receptor inhibitor lactisole.

Main Results:

• Branched MOS samples with average DPs of 6, 10, and 18 were successfully prepared, containing 9-13% α-1,6 branch points.
• All MOS samples were significantly detectable (d' = 1.81-2.9) when lactisole was absent.
• MOS detection was abolished (d' = 0-0.61) in the presence of lactisole, indicating sweet receptor involvement.

Conclusions:

• The α-1,6 branching in maltooligosaccharides is essential for their detection via the human sweet taste receptor.
• These findings refute the existence of a specific
• starchy
• receptor for MOS detection.
• Carbohydrate taste perception is critically dependent on specific glycosidic structures and branching patterns.