Have you ever wondered why sweet foods taste as good as they do? Or why super bitter foods aren’t nearly as appealing? You can thank your five types of taste receptors for these preferences and for the ensuing reaction that occurs when you eat them. The sense of taste, also known as gustatory perception, is based entirely on the reactions that occur when taste receptors found all over the mouth and tongue are exposed to a stimulant.
Taste versus flavour
While taste and flavour may seem interchangeable they are actually different terms to describe two separate physiological reactions. Flavour is a combination of taste and smell working together to produce a heightened sensory experience. As an experiment try eating a small piece of chocolate while plugging your nose, you’ll find that the chocolate suddenly loses its distinctive flavour when you aren’t able to smell it. Wine glasses with different-sized bowls are a great example of putting this science to a practical use; the taster is able to get a flavour-optimized experience based on the shape of the glass.
Why do we taste?
Taste receptors act as a metabolic response, not only in our mouths and throats but also in our gastrointestinal tract and in our pancreas. This warning system is an important part of how our bodies function, it triggers reactions further along the digestive tract that allow your body to react accordingly. This reaction is so strong it will still occur even if the food has been spit out. For example, an intensely bitter tasting substance could act as a warning that what you are about to consume is toxic.
What’s in a taste?
Sweet taste receptors respond immediately and with enthusiasm to carbohydrates in general, especially very sugary carbohydrates. Food that tastes sweet tends to be very calorie dense, explaining why you crave them when you have very little energy or if you haven’t had enough sleep. It has also been theorized that sweet taste receptors have an evolutionary role which helped early humans detect when fruit was ripe.
Scientists hypothesize that salt is something that humans crave because it is a necessary nutrient for survival, however, humans are unable to store excess reserves of salt in the body, so we must continually seek it out in our foods. Taste receptors that sense saltiness are unique because salt is desirable in measured small amounts but excess amounts are completely inedible if not toxic. A study conducted on genetically engineered mice has shown that sour and bitter receptors, both considered adverse tastes, are components of how we can identify when we’ve had too much salt.
Sour taste receptors are sensitive to acids and are similar to receptors that detect saltiness in that mildly sour foods are enjoyable but too much of a sour taste is deeply unpleasant. Scientists are still unsure of the exact purpose of sour taste receptors, although there are theories suggesting sour taste receptors exist to make sure that a sufficient amount of vitamin C is being consumed.
Humans have more bitter taste receptors than any other kind and with good reason! These taste receptors play an important part in preventing us from ingesting toxins that could be potentially harmful or even fatal. Despite the way taste receptors strongly react to bitter tastes, it’s still a desirable component in food and drink when present in small amounts.
A relative newcomer to our other taste receptors, umami is defined by a deep savoury taste that can be found in the form of MSG and in cured and roasted meats, anchovies, mushrooms and cheeses. First discovered in 1908 by Dr. Kikunae Ikeda of Tokyo Imperial University the word “umami” comes from the Japanese words umai, meaning delicious and mi meaning taste. Umami tastes are largely associated with fermented, dried and cooked foods which all contain amino acids that are beneficial to human health.