A new sixth taste has been identified by researchers at the University of Southern California. The classic tastes of sweet, sour, salty, bitter, and umami have been known for a long time, but now Ammoniumchloride has been added to the list. This taste is found in foods such as licorice, which is bitter, salty, and a little sour. The different tastes are created when specialized taste receptor cells (TRCs) on the tongue interact with chemicals in food. The TRCs recognize the basic tastes and send signals to the brain, which then determines whether the food is perceived as bitter, sweet, umami, sour, salty, or a mixture of these.
According to the researchers, sour-tasting foods have a low pH value and contain many hydrogen ions. When sour taste receptors are exposed to acids, they form an electrical signal due to the transport of hydrogen ions. The researchers discovered that sour TRCs express the otopterin1 (Otop1) gene, which encodes the protein OTOP1, which in turn forms a proton channel through which cells recognize the sour taste. In their study, the team examined how sour TRCs and OTOP1 recognize Ammoniumchloride. They introduced the Otop1 gene into human cells grown in the laboratory and exposed some of them to acid or Ammoniumchloride. They found that Ammoniumchloride effectively activated the OTOP1 receptor like acid.
The researchers suspect that the ability to taste Ammoniumchloride has evolved to help organisms avoid harmful substances. Ammonium is generally toxic to humans and many animals, so many can recognize it in the environment. In future studies, the researchers plan to examine the reaction of the OTOP1 receptor to other substances and analyze how Ammoniumchloride affects the sour taste. This could lead to new insights into taste and its development.
In conclusion, the discovery of a new sixth taste is an exciting development in the field of taste research. The identification of Ammoniumchloride as a taste is significant, as it could help us better understand how organisms have evolved to avoid harmful substances. The researchers’ findings could also lead to new insights into the complex mechanisms of taste perception and how they influence our food choices.
