Writing in Chemical Senses, researchers from Penn State in the USA reveal that variations in multiple genes could play an important role in how people's taste receptors send signals, leading to a wide spectrum of taste preferences for artificial sweeteners.
Led by Dr John Hayes, the team suggested that these varied, genetically influenced responses may mean that food and drink companies will need a range of artificial sweeteners to accommodate different consumer tastes.
"Genetic differences lead to differences in how people respond to tastes of foods," explained Hayes, who noted that the new research shows individual genetic differences can mean some consumers find non-nutritive sweeteners such as Acesulfame-k (Ace K) more bitter than others.
"We've known for over 80 years that some people differ in their ability to taste bitterness, but we have only begin to tease apart the molecular basis of these differences in the last decade," he said - revealing that while some people find Ace K sweet, others find it both bitter and sweet.
The team used genetic profiling to look for differences that could explain the findings - revealing variants of two bitter taste receptor genes - TAS2R9 and TAS2R31 - that were able to explain some of the differences in Ace K's bitterness.
These two taste receptor genes work independently, but they can combine to form a range of responses, explained Alissa Allen - who also worked on the study.
The team genotyped 108 participants for genetic variations in the five TAS2R receptors before asking them to rate the bitterness of 25 mM Ace-K on a general labeled magnitude scale.
"We found 2 single nucleotide polymorphisms in TAS2R31 were associated with acesulfame potassium bitterness," they said. "However, TAS2R9 alleles also predicted additional variation in acesulfame potassium bitterness."
"We modeled the simultaneous influence of these single nucleotide polymorphisms on acesulfame potassium bitterness; together, these 2 single nucleotide polymorphisms explained 13.4% of the variance in perceived bitterness," they reported.
"These data suggest multiple polymorphisms within TAS2Rs contribute to the ability to perceive the bitterness from Ace-K."
Source: Chemical Senses
Published online ahead of print, doi:10.1093/chemse/bjt017
"Bitterness of the Non-nutritive Sweetener Acesulfame Potassium Varies With Polymorphisms in TAS2R9 and TAS2R31"
Authors: Alissa L. Allen, John E. McGeary, Valerie S. Knopik