Eat with your ears, savor with your nose!

Food is a loyal companion throughout every one of our daily activities, both as a source of nourishment, but also (and above all!) as a sensory experience that’s capable of arousing various sensations.

Exactly which sensations come into play when we’re eating?

TASTE

Described by many, in numerous ways, taste is definitely the first sensation that comes to mind and the one that we’re used to paying the most attention to. While it isn’t the first sense to be stimulated during our journey through the complex experience of eating, it does deserve due attention. In fact, some interesting discoveries have been made over the past two decades.

Let’s start with the basics. Five fundamental tastes are universally acknowledged: sweet, salty, sour, bitter, and umami (or savoriness). The perception of these tastes happens when the chemical molecules in the solution – in this case our saliva – activate the receptors located on our tongue and soft palate. Once activated, these receptors – known as taste buds – send a signal to our central nervous system thanks to the complex innervation that these structures possess.

At this point, the situation gets interesting: for a long time it was believed that each area of the tongue was dedicated to the perception of a single taste; the tip perceived sweet, while the back part perceived bitter, and the sides perceived salty and sour. 

We’ve definitely all heard this. 

At the beginning of the 21st century, this theory was disproved! Each area of our tongue is able to perceive all of the tastes, so this map is no longer accurate. Try it yourselves. Where do you really perceive sweet or the other basic tastes? 

What other developments can we tell you about on this front? You might be interested to know that science is studying a sixth fundamental taste, kokumi, or a rich taste that can be attributed to fat. Or better yet, to the fatty acids of which it is composed and that have their own flavor that can be distinguished from the others. Maybe some of us already imagined this; on YouTube it’s been possible to find, for some time now, videos that experiment with the different flavors of a hamburger or meat depending on the fat in which it’s cooked! Furthermore, not everyone likes fatty foods to the same extent. Some love them, others hate them.

Science suggests that this difference in preference for more or less fatty foods could be due to varying sensitivities to their tastes. Furthermore, we have a threshold of perception for this taste as well. Beyond a certain amount, we’re not able to perceive a greater intensity, even if the concentration of fatty material is doubled or tripled.  These discoveries shine light on how kokumi could influence consumption and create a predisposition for obesity, alluding to a new role that our taste can play in both controlling food intake and regulating weight.

SMELL

What a magical tool. Some have an incredibly fine-tuned sense of smell, others less so. 

In any case, it’s one of the first senses that we use when we taste a dish. How many times have our stomachs begun to rumble even just from catching a whiff of the delicious aromas emanating from our grandmother’s kitchen or as we’re walking down the street?

In fact, its role is to alert our stomach to the imminent arrival of food. Nevertheless, if trained, it allows us to appreciate the infinite aspects of a wine, a beer, or a particularly complex dish.

However, the smell receptors are found deep within the nasal cavity. This ensures that this precious sense remain intact, but also means that we perceive only a small part of the substances present in the air. We were interested to discover that people are actually able to perceive smells in two different ways: the first is direct perception through the nose. 

What a revelation, right? In this case we talk about smells. In the second case, a substance’s smell is perceived through the mouth. In this case, the olfactory epithelium is stimulated by the passage of airborne molecules through the pharynx, which is connected to both of these cavities.

The next time you pay attention to the sensations that a food arouses in your mouth or after swallowing, refer to these with the world flavor. A beer doesn’t taste like fruit, but rather has a fruity flavor because the molecules responsible for this perception are airborne substances that have reached your olfactory epithelium via your pharynx!

SIGHT

Along with smell, this is the first sense responsible for our reactions to a dish or beverage. It’s definitely important to mention it because it’s able to affect our overall perception of a food. Dozens of studies demonstrate how visual stimuli can modify the taste and intensity that’s perceived, as well as the degree to which a food is accepted and the quality of the product being tasted. In 1995, a study conducted by Philipsen D.H. that focused on two groups of individuals, 18-22 years old and 60-75 years old respectively, demonstrated how the perception of cherry juice can change. The samples of juice differed in the quantity of red coloring. The results of this study highlighted how the same beverage, but with a different color, is perceived to have a different taste. In fact, even though the juice was always cherry flavored, colors tending towards orange or yellow were recognized by the two groups as orange juice or a blend of fruits. Furthermore, as the intensity of the red color increased, so did the intensity of the cherry flavor perceived by the second group. Clearly quite a difference! Studies like this one demonstrate that people get used to specific combinations of tastes and colors, and that when we look at a dish, its colors already create certain expectations within us!

CHEMESTHETIC AND TACTILE SENSATIONS

Don’t be fooled by the fancy sounding and complicated name. Chemesthetic sensations are those perceived by the mouth that are analogous to the tactile and thermal sensations perceived by the body’s surface. Among these are the biting sensation caused by spicy foods, the refreshing sensation of menthol, the irritating sensation of carbon dioxide bubbles, and the puckering sensation – known as astringency – which we feel when we bite into an unripe fruit. 

The list doesn’t end here: among the tactile sensations that are responsible for the agreeability or not of a dish, there’s also its consistency or texture. A highly dynamic characteristic since, from the moment we bite into something until we swallow the mouthful, the structural characteristics change completely. 

The scientific community is still feverishly researching this last characteristic as not all of the events and sensations that occur during chewing are clear. 

“How fascinating it is to eat!”

HEARING

The last stop on our journey: hearing. We like to call this sense the cherry on top of the experience. In fact, when you sigh with satisfaction while munching on potato chips or cookies, it’s also thanks to this sense, which completes our perception of a product’s consistency. Many times it’s on this very experience that our preference for one brand of cookies rather than another is based. It seems superfluous to ask who prefers a crunchy and fragrant cookie as compared to one that’s stale and soggy!

EXPERIMENT WITH US!

This is where our journey ends. However, before we leave you, we’d like to help you experiment with your senses, which are the source of both joy and pain in the kitchen (and outside of it)! 

That’s why we’d like to offer you the following challenges:

-experiment with different wines and beers in the dark or blindfolded. Are you able to distinguish an IPA from a lager or a stout?

-invite your friends to a lunch without smell! The challenge starts as soon as you plug your nose: will anyone be able to recognize the flavor of various dishes? Probably not, at most just some basic tastes. For hearing, we suggest a solitary experience: a headset and two cookies, one just opened and the other left out even for only a day. You’ll “hear” how the situation changes!

If you’ve tried or will try one of these challenges, let us know about it below the Instagram post!

BIBLIOGRAPHY

Keast, R. S., & Costanzo, A. (2015). Is fat the sixth taste primary? Evidence and implications. Flavour, 4(1), 1-7.

Pagliarini, E. (2021). Valutazione sensoriale: aspetti teorici, pratici e metodologici. Hoepli Editore.

Porretta, S. (2000). Analisi sensoriale & consumer science. Chiriotti Editore.

Philipsen D.H., Consumer age affects response to sensory characteristics of a cherry flavored beverage. Journal of Food Science, 60:364-368, 1995.