The sense of taste, thanks to the 10,000 taste buds that make it up, allows us to experience an infinity of flavors that, yes, can be classified into specific families. Let’s analyze its physiological bases.
- We recommend you read: “Sense of smell: what it is, nerve and brain parts, and functions”
How do we define flavor?
Taste is one of the 5 senses that the human being possesses. The specific function of this sense lies in being able to detect what a food tastes like , being able to identify what we are eating by its flavor. For this reason, in most cases, the main function is to allow food to be differentiated and to enjoy the food.
But if we look at its most functional utility, we can point out that if we know the flavor of certain foods and we perceive it differently from its usual form, it can indicate that the food may be in poor condition. In the same way there are flavors, such as the bitter one that we propose below, which shows a tendency to be related to foods that are not in good condition and therefore we must be careful to avoid any affectation.
Despite finding the taste receptors on the tongue, a large part of the taste we perceive from food, it is estimated that close to 60%, comes from the function performed by the nose detectors , that is, it depends on the smell. For this reason, when we catch a cold and feel congested, with mucus in the nose, it is easy for us to lose or diminish the perception of taste.
biological functioning of flavor
As we have pointed out, taste receptors are located on the tongue and are known as taste buds, although we can also find receptors on the palate and cheeks. Humans have approximately 10,000 taste buds that show a short life, regenerating more or less every 2 weeks.
Taste receptors are distributed throughout the tongue according to the flavor they detect, thus sweet receptors are located in the front area of the tongue, salty after sweet and right on the tip of the tongue, located on each side of the organ; the sour followed by the salty and finally the bitter on the back of the tongue.
Recently, in the 20th century, a new taste called umami was added, whose receptors are located in the central part of the tongue. Note that the areas are not perfectly delimited , we can find recipients of different tastes spread throughout the language. For example, salty receptors can also be located on the tip of the tongue sharing an area with sweet.
Once the food has activated the taste buds, this information is transmitted through the cranial, facial, glossopharyngeal and vagus nerves, to the primary taste cortex located in the lower part of the parietal lobe, passing first through the thalamus. In this way, we will be able to detect and differentiate the different flavors.
What kinds of flavors are there?
Now that we know what the main flavors are, we will describe their main functions. Likewise, other flavors have also been proposed that, despite not having the same scientific support, we also see as interesting to propose.
1. Salado
Salty receptors mainly detect sodium (Na) molecules and to a lesser extent those of potassium (K) or other alkaline metals. Specifically, the taste buds that are responsible for perceiving the salty taste with the foliate ones, located on the lingual mucosa on the lateral and posterior part of the tongue, as well as we can also find some on the dorsal, superior part.
The main salt we consume is sodium chloride (NaCl), also known as common salt, which generates a chemical reaction in the receptors so that information is produced and transmitted. Sodium is a particularly important molecule for the proper functioning of the human body, playing a fundamental role in the transmission of information from neurons, that is, in the functioning of our brain, as well as the good condition of our muscles.
Another of the remarkable characteristics of salty products, and especially of sodium chloride, is its function as a flavor enhancer . For example, it is common to add a small amount of salt when we are making pastries, in sweet foods. Likewise, both the sweet and salty taste are linked to the presence of essential nutrients in the food, that is, in small doses, it indicates that the food is healthy and nutritious.
2. Dulce
Sweet is one of the most desired flavors, which gives us the greatest pleasure. Specifically, the specific taste buds for the sweet taste are called fungiforms and are especially sensitive during the stages of childhood and old age.
The main molecules that sweet receptors detect are carbohydrates , as well as sucrose, fructose, some amino acids, which we find in foods rich in protein. The most common way to sweeten a food is to add sugar, although we can also obtain the sweet taste naturally, for example when we eat a fruit, it already shows a sweet taste thanks to the fructose.
Sugar, especially glucose, is one of the main sources of energy in our body, offering us fuel immediately. Without the consumption of sugar our brain does not work the same, we are not as functional.
3. Acid
The acid taste, unlike those proposed to date, is no longer liked by everyone and has a greater tendency to be associated with spoiled food or toxic substances, such as poison. For this reason, it can act as an indicator for us to stop consuming. the product.
Unlike the other basic flavors, acid is not related to any specific type of taste bud , yet this flavor is detected the same. When acids come into contact with water, they give rise to hydronium ions (H3O+), which are the ones that interact with the receptors, allowing the perception of acid taste.
An indicator that is associated with acidity is pH, which indicates the degree of acidity. In this way, the interval 0-14 is proposed, considering 7 as the midpoint, neutral, lower values will imply acidity.
4. Bitter
Bitter, like acid, is not a pleasant taste. But, despite not generating a good experience for us, it is perhaps the most functional if we take into account its effect on survival . This unpleasant taste is commonly used to distinguish healthy, nutritious foods from toxic substances or foods that can cause us harm.
The substances that are most linked to the bitter taste are high molecular weight inorganic salts, such as magnesium. It is believed that these salts act mainly on the goblet-like taste buds, which are present in smaller numbers, although this opinion is not defended by everyone.
Despite its action as an alarm to identify products in poor condition or harmful, there are also foods that have this flavor and are not bad, such as coffee or pure chocolate, without added sugar, or beer. Likewise, some medications, such as antibiotics, can also show a bitter taste.
5. Umami
Umami is also considered one of the basic flavors, although it was incorporated more recently than the previous ones. It is difficult to describe this type of flavor, although it is noted that it is related to the best and most delicious foods.
The amino acid glutamate is responsible for generating this particular flavor . Umami is not characteristic for its intense taste, but it does help enhance pleasant flavors. For example, in salty foods, umami increases this flavor, decreasing the amount of salt needed to achieve the desired sensation.
Umami is not linked to a specific type of taste bud, it can be detected by papillae located in different regions of the tongue. Foods that contain glutamate and are therefore associated with umami taste are meats and vegetables, as well as fish and shellfish.
non-basic flavors
People use the term hot flavor when we eat foods like chillies or chili, but these foods don’t really taste or smell . It is a type of organic chemical substance called capsaicin, which, when in contact with the heat and pain receptors, distributed throughout the body, generates the sensation of spiciness.
A recently discovered flavor is adipose, this was detected by seeing that there was a type of taste receptors that act especially with lipids, that is, with the fats that give rise to adipose tissue.
Finally, the astringent taste creates in the subjects a sensation of vocal dryness and bitterness. It is a flavor related to wines, especially red wines, we can also perceive it in tea and in some fruits such as persimmons or dalites.
To the classic question “what do you do?” I always answer “basically I am a psychologist”. In fact, my academic training has revolved around the psychology of development, education and community, a field of study influenced my volunteer activities, as well as my first work experiences in personal services.