17th September, 2013 by Lucy Shaw
The presence of cork taint in wine shuts off signals from our noses to our brains, preventing the ability to detect other odours, Japanese scientists have found.
As reported by the BBC, researchers at Osaka University have discovered that the suppression of our sense of smell by the chemical 2,4,6-trichloroanisole (TCA) leads drinkers to imaging “pseudo-olfactory sensations” such as the damp cloth and wet dog aromas traditionally associated with corked wine.
“It has long been thought that TCA causes excitation of sensory cells to induce unpleasant sensation,” professor Hiroko Takeuchi from the university’s Graduate School of Frontier Biosciences told the BBC.
“However, our findings show that TCA suppresses activity of sensory cells, we also speculate that this suppression may cause a musty smell that is a typical feature of corked wine,” he added.
The team was investigating how TCA functions by analysing how both newts and people responded to the chemical, publishing the report in Proceedings of the National Academy of Science.
The study monitored the activity in the cells of newts exposed to TCA and found that rather than sparking odour perception, cork taint suppressed it.
A separate study measured how 20 participants reacted to the presence of cork taint in samples of wine, and found that aroma perception was reduced when TCA was present.
TCA suppresses the nose’s primary smelling receptor, which converts smells to electrical signals sent to the brain.
The study, which has implications beyond wine, found the brain interprets this reaction as an unpleasant odour.
“Our research shows that the reduction of quality found in foods and drinks is in part due to the generation of a suppressor, rather than the reduction of original flavour,” Takeuchi told the BBC.
The team wants to use the findings to develop ways to deliberately weaken the nose’s sense of smell in order to mask bad odours in certain products.