The Role of the Sense of Smell in Taste Perception
The sense of smell plays a very important role in taste.
The smell of freshly baked bread, the aroma of pies from a cafeteria, or the smell of freshly ground coffee is all delightful. So attractive are these aromas that they encourage one to taste those foodstuffs. Indeed, in some circumstances, the saliva glands go into action and secrete the saliva necessary to be able to taste. Since your perception of scents is a thousand times sharper than your ability to taste, odors play an important role in the "taste" of foods. Yet the relationship between our senses of smell and taste goes even further.
How do you tell blackcurrant jam from strawberry?
If you think the answer is obvious, and that you just have to taste them, you are mistaken, because tasting alone is not enough to tell the difference between the two. If you had no sense of smell, you would describe the taste of both as "sweet," but not be able to describe their different features.
The reason is that we need our sense of smell to be able to perceive the taste of anything we eat, and cannot fully appreciate the flavor of anything without smelling it. What makes something pleasant to eat is the combination of both its taste and aroma. Researchers emphasize this by saying that taste is 75% smell.
As we know, appetizing smells encourage people to eat and drink. Indeed, people who lose their sense of smell have no great desire for food. Remember times when you had a cold or the flu? Your meals had no flavor at such times because scent molecules failed to reach the scent preceptors—for which reason your sense of smell was temporarily lost.
It is He Who made the Earth a couch for you, and the sky a dome. He sends down water from the sky and by it brings forth fruits for your provision...
(Surat al-Baqara: 22)
To make this easier to understand, blindfold friends and block up their nostrils, and then ask them to place first, a slice of potato and next, a slice of apple on their tongues. Your friends will be unable to tell which is which, because both cause a mild sweet sensation. It is possible for your friends to give the right answer only if they start chewing, because that will release scent particles that float up through the back of the mouth to reach the scent region in the nose. Potato and apple will then become apparent.
Noteworthy too is that the mouth and nose are ideally positioned in the human body, in very close proximity to one another. An air passage connects the scent perception zone in the nose to the oral cavity. Were it not for that connection and that proximity, or if the scent receptors were located in another part of the body, what would happen?
Any alteration to the current state of affairs would mean a major loss of taste perception, because the mouth, nose and scent perceptors have been created in exactly the right form and locations.
Indeed, it is revealed in the Qur'an that God created human beings within a particular order:
O man! What has deluded you in respect of your Noble Lord? He Who created you and formed you and proportioned you and assembled you in whatever way He willed. (Surat al-Infitar: 6-8)
To summarize, the concept we define as "flavor" is a combination of taste and smell. Therefore, if we had no sense of smell, our sense of taste would have little purpose. In order to perceive flavors, we need the scent receptors in the nose just as much as taste preceptors on the tongue.
No doubt the cooperation between the organs and senses for taste and smell results from a special design. It is perfectly commonplace for conscious humans to agree to work towards some common objective. But similar cooperation among billions of cells devoid of any intelligence of consciousness can be explained in only one way: it is God, the Lord of the worlds, Who placed them at the service of humans and Who keeps them under His control at all moments.