If you enjoy washing down salted crisps with a cool cola, you鈥檙e not alone. It turns out that an acid found in these beverages appears to open up sodium channels in our tongue鈥檚 taste receptors, enhancing the salty flavour. Adding the acid to food might therefore let manufacturers use less salt, which can raise the risk of high blood pressure, leading to heart attacks and strokes.
at the University of Tennessee Health Science Center and his colleagues alternated applying two water solutions to the tips of 12 people鈥檚 tongues. One of the solutions contained only water, while the second also contained a little table salt.
When the participants identified the salty solution, they rinsed their mouth with water and repeated the process, with the second solution containing ever decreasing amounts of salt until they were unable to differentiate between the two.
Advertisement
Next, the participants rinsed their mouths with diluted phosphoric acid, which is added to sodas like cola to give them tartness. The researchers repeated the experiment, finding that the participants could then identify the salty solution at a lower salt concentration.
To gauge why this may occur, they then studied the immature egg cells of African clawed frogs, . They found that exposure to phosphoric acid increased the amount of time that the cells鈥� epithelial sodium channels (ENaCs) were open.
These channels are in our tongue鈥檚 taste receptors and affect how salt is absorbed into our body. By opening the channels, phosphoric acid may cause our taste cells to perceive a saltier flavour.
Collier and his team aren鈥檛 sure why phosphoric acid opens ENaCs or whether this causes us to consume more or less salt. 鈥淢ore activity in the channel could mean better ability to detect salt at lower levels, so you crave less salt and take in less of it through your diet,鈥� says Collier. 鈥淏ut the hypothesis could actually go the other way as well. You could be turning up the volume on this pleasant flavour, which could drive people to eat more salt.鈥�
at Vanderbilt University Medical Center, Tennessee, says this research might one day help doctors treat high blood pressure. If your taste of salt is enhanced via the addition of an acidic flavour or the manipulation of ENaCs, then you may put less salt in your food, she says. 鈥淧erhaps food manufacturing industries can use acid to enhance the perceived saltiness, which has potential to reduce the cardiovascular burden.鈥�
bioRxiv
