A recent research study has identified a new taste response that had not been recorded previously. Results of the study, published this October found that in addition to the five basic tastes humans can also detect ammonium chloride, creating a strong sensation, which the researchers described as “bitter, salty, and a little sour.”
According to the report, ammonium chloride activates receptors in our cells that detect salty and sour tastes. The new ammonium chloride taste adds to the five basic tastes that we already know of: sweet, sour, salty, bitter, umami, which is a savory flavor similar to that of monosodium glutamate.
The ability to taste ammonia — a smell and taste that indicates certain foods, including seafood and meat, may have become spoiled — could be a survival mechanism that evolved over time. The ability to detect this taste, and then avoid it, would be a way to ensure that we do not eat spoiled meat or fish that could contain dangerous bacteria that could harm us.. Taste serves an important function in people. For example, while taste buds help us experience flavor and decide what to eat, they also help us detect toxins and keep us safe. When our taste receptors are activated, they send messages to our brain that help us perceive taste and react accordingly.
Based on that information, we can decide if food is good or dangerous, or if we want more of it. Ammonium can be toxic at high doses, and many people and animals find the taste of ammonium aversive. It is believed this prevents many animals from consuming waste and decaying matter. In certain scenarios, people can actually enjoy the taste of ammonium chloride.
For instance in Scandinavian countries, it is used in salty licorice. The discovery of a sixth sense of taste has led some scientists to speculate that there could be many other tastes that have so far not been identified. Future studies can help us identify how human taste cells and receptors respond to various substances. To determine how ammonium activates taste cells, the researchers exposed cultured human cells to ammonium chloride. They found that the compound activated a specific type of receptor called OTOP1 in our sour-taste cells. The researchers expanded their study to investigate how mice responded to water with and without ammonium chloride.
They found that rodents without the OTOP1 receptors did not react to ammonium chloride, whereas mice with the receptors avoided the compound. The study suggests that the response in both human and mouse OTOP1 channels is similar to how the receptors reacted to acid. This finding helped the researchers to surmise that OTOP1 receptors are essential for helping humans detect the taste of ammonium chloride.