How bitter is it? Odor induced taste modulation of bitter ligands

The presence of bitter compounds in healthy foods and pharmaceuticals can steer people away from products that benefit health. The examination of bitter taste is especially complex due to the varying taste phenotypes present in our population and the ability of one bitter ligand to activate multiple receptors. Several factors, including concentration of stimuli, expectation biases, and blocking of nasal pathways can alter the overall flavor and basic taste perception, making it crucial to translate cellular assays to in-vivo models. This study aims to better understand retronasal olfaction and chemesthetic irritation mechanisms of bitter taste to pharmaceutical and food-grade ligands utilizing a panel of healthy adults who scored the bitterness and irritation of suprathreshold concentrations of nine stimuli with and without nose clips. The study used duplicate taste intensity ratings from 47 participants who were trained to use the general labeled magnitude scale (gLms). Participants rated the smell, irritation, overall flavor, and the like/dislike experienced for most compounds. Out of the nine agonists (Naringin 10/50/100mM, Ibuprofen sodium 10/44/100mM, Theobromine 1/10/30m, Acesulfame K 1/12/100mM, Sodium Benzoate 50/100/300mM, Acetaminophen 1/10/100mM, Propylthiouracil 0.056/0.18/0.56 mM, Dextromethorphan 0.01/0.1/1mM, and Diphenhydramine 0.5/1/10 mM) only the Naringin showed change in bitterness ratings based on nose clip condition at the highest concentration, with the presence of retronasal olfaction decreasing bitter perception (p=0.005). Ibuprofen (p=0.01) and Theobromine (p=0.03) were the two compounds to show significant differences in irritation ratings based on nose-clip condition. For both Theobromine and Ibuprofen, ratings for irritation increased without the nose clip proportionally to the concentration

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Food Science & Human Nutrition

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Hall, Leah

Contributors dc:contributor

• Pepino , Yanina
• Cadwallader, Keith
• Miller, Michael

• Bitter
• Retronasal
• Chemesthetic

Statement dc:rights

• Copyright 2024 Leah Hall

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/124519

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F124519