The 5 types of flavors, and where their receptors are on the tongue

We review the main flavors detected by the tongue, and possible candidates for taste.

Flavor and taste are words that evoke pleasure and well-being.They speak to us of generally positive perceptions and experiences that our organism allows and facilitates in our daily lives. And they are words associated with the fact of feeding, of eating.

Feeding and nourishment are fundamental for our survival, but the truth is that the different elements have different compositions and chemical properties that both smell and taste are able to perceive. And the fact is that we have organs with specific receptors for these properties, something that allows us to perceive different types of flavors.

Throughout this article we are going to mention the main types of existing flavors.

The sense of taste and flavor

Before commenting on the existence of different types of tastes, it is worth analyzing first of all what a taste is and where it comes from. We refer to taste as the perception by the organism of the chemical properties of an object or food, which is linked to the sense of taste. which is linked to the sense of taste. Thus, taste itself is the perception that enables this sense: just as sight enables us to see images and hearing to capture sounds, in the case of taste we capture flavors.

Physiologically, the perception of taste is due to the action of certain receptors called taste buds, which are found in the numerous papillae located mainly on our tongue (although there are also some on the palate and pharynx).

These receptors are activated when a substance with certain chemical properties reaches them.These will generate a response that will later be transferred to the nerve pathways and after being processed will be identified with taste.

Although we generally associate taste merely to pleasure, the truth is that being able to perceive them can mean the difference between life and death, being of vital importance for survival. Thanks to the sense of taste and the perception of the taste of food we can detect the chemical properties of what we eat and predict whether or not it can be negative for our survival or, on the contrary, it favors it.

Types of flavors

As mentioned above, our sense of taste allows us to detect a certain variety of flavors thanks to the receptors available to us. thanks to the receptors we have in our tongue (and part of the palate). (and part of the palate). Mainly and so far, five basic flavors have been found that our organism is able to capture.

1. Sweet

The sweet taste is one of the most basic and relevant for human beings as well as for other species, being one of the first tastes to be perceived and one of the most sought after by most living beings. one of the first tastes to be perceived and one of the most sought after by most living beings..

This taste is generally associated with hydrocarbon compounds such as sugars, and it is generally considered that most of the receptors for this taste are located on the tip of the tongue.

Likewise, it is also one of the tastes that is most associated with odor, the perception of this taste and its intensity being easily altered depending on the aroma of the food in question. Generally, at least in humans, it tends to be one of the preferred tastes throughout life, especially in childhood and old age.

2. Salty

The second of the basic tastes is the so-called salty taste. This is a reaction to the detection of sodium chloride and other salts in what we to the detection of sodium chloride and other salts in what we put in our mouths.It is essential because it helps us to look for foods that contribute to regulate the electrolyte balance of our organism and maintain homeostasis.

In fact, there is a so-called salt appetite linked to the Biological search for the regulation of this need. It tends to become more and more relevant and sought after by human beings as we grow and mature, and its receptors are mainly located in the bands on the tip of the tongue..

3. Acid

This taste is generally linked to sourness, associated with spoiled food. This taste comes from substances that are, as the name of the taste indicates, acidic, and which could have some that could have certain danger for the organism. That is why it is generally unpleasant and avoided by most people, at least in the first stages of life.

However, they also contribute to regulate the pH of our organism, their perception being linked to the electrical charge of the molecules that come into contact with their receptors (apparently their channels being sensitive to the concentration of protons in their molecules).

It is present in such important foods as citrus fruits. Interestingly, it also seems to be linked to the sense of balanceThe type of channel (OTOP1) is also related to its perception in the vestibular system. Its main receptors are located in the posteriormost bands or sides of the tongue, close to the palate and pharynx.

4. Bitter

This fourth basic taste is also one of the most relevant and one of the first to be possessed, given that it has the particularity that is mostly unpalatable to humans and often warns us of spoiled or potentially toxic foods. and usually warns us that we are in front of food in bad condition or with toxic potential. However, many people like some foods that have this type of taste, including beverages such as coffee. Generally, it is generated by inorganic salts.

The perception of this taste is important throughout life, and generally the foods we like come to do so through a process of habituation. through a process of habituation in which we initially find it unpleasant. Most of the receptors of this taste are located in the innermost part of the tongue, in its medial part.

5. Umami

The types of tastes traditionally recognized as such, and in fact the ones that most of us learn during formal education, are the four previous ones. However, in recent years a new taste has been discovered which even has specific receptors on the tongue.

We are talking about umami taste, which roughly translates as "tasty/delicious", and which has nowadays and which today has entered into the classification of basic tastes. The perception of this taste is linked to the effect of glutamic acid or monosodium glutamate. It is found in a large number of products, including meats, sauces (often used as an enhancer, in fact) and cheeses. It is believed that the receptors for this flavor are distributed throughout the tongue, on its surface.

Two other proposed flavors and non-flavors

The flavors officially accepted as such are those mentioned above, although there are other types of proposed flavors that are other types of proposed flavors that are currently under investigation.

Starchy: the taste of starch and flour.

Another possible taste that has been investigated at universities such as Oregon has not yet gone beyond a theoretical assumption, as no specific receptor has been found for the time being (it is under investigation). This taste is derived from the perception of the oligomers of glucosewhich can be detected even when the sweet receptors are blocked.

This is starchy, a possible sense of taste linked to the perception of starch, starch and products derived from flour such as bread, pasta or rice, and which, according to the experimentsand which, according to the experiments, would be perceived differently depending on the culture and the type of food we use.

Fatty taste

Probably most of us will have noticed at some time the taste of the fat of a piece of meat, being something that some people consider unpleasant while for others it is a pleasure.

And a few years ago it seems to have been found that at least the human being possesses a receptor that detects fatty acids. a receptor that detects fatty acids (although this is still under investigation (although it is still under investigation since it is not known exactly how the information coming from them is processed).

This taste would be a response to the detection of lipids in food, which can be detected by itself (for example in fried foods) although it is usually linked to the perception of other tastes. On its own, it usually manifests itself as similar to bitterness. Interestingly, it seems that those who are less able to detect it tend to be more prone to obesity.

A non-flavor: spiciness and the pleasure of pain

Although when we talk about flavors we generally think of the first four we have mentioned (sweet, salty, sour and bitter), many people come to think of the possibility of considering spicy among them. And the fact is that spicy food has been part of the gastronomy of a large number of cultures throughout history, and it is not uncommon to hear that a food has a spicy taste or flavor. throughout history, and it is not uncommon to hear that a food has a spicy taste or flavor.

However, the truth is that the existence of a spicy taste is not considered as such, since the sensation of spiciness produced by a food is not a perception of the chemical properties that confer taste to a food but, in fact, it is a perception between thermal and pain. Spiciness does not have a specific receptor, but owes its perception to the release of capsaicin and other components, which generate that the receptors of the tongue raise their temperature in such a way that they generate a hurent or itching sensation, which is what we perceive as spicy.

Bibliographic references:

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