Your sense of taste is very similar to your sense of smell, both sensors are stimulated by directly absorbing chemicals into the cell. There is a reason that food tastes different if you are congested or if you hold your nose.
The main difference between taste and smell is the location of sensors and the state in which the chemicals are absorbed. Smells are absorbed solely in the gaseous form while taste absorbs chemicals in solution. Usually that solution comes from the water within the food or from your saliva. But enough with the comparisons , let’s jump into taste!
Your taste sensors are found mostly on the tip and edges of your tongue, though some are also in your throat and roof of your mouth. Each taste sensor has receptors that reach up to near the surface of the tongue, just underneath the epithelial tissue. The surface of your tongue is covered in bumps and each bump has pores to allow a small amount of chemicals to diffuse into the receptor cells.
Each taste sensor dies and is replaced every 10-14 days, which is a good thing because we kill our taste sensors all the time. Eating food that’s too hot, too spicy (acidic), or with overly powerful flavors can kill off sensors. We feel the death of our taste sensors as pain.
When we continuously eat spicy, hot or powerful foods, the taste sensors do not grow back in as great a number. This is the reason why people who eat very spicy foods can only taste more spiciness, they’ve reduced the amount of sensors that they have in their tongues! On the flip side, those who practice their sense of taste, like wine connoisseurs, can detect flavors other people cannot.
As an organism, you need to eat and your adapted method of eating is to place food in your mouth to then be swallowed and digested. The digestion process allows for the molecules within the food to be absorbed into your blood and distributed to the cells throughout your body.
Anything you swallow can eventually spread to your entire body. That can present a major problem if you swallow something that harms your cells. Taste to the rescue! Those individuals who had the ability to determine exactly what they were eating, were better able to avoid hazardous foods and didn’t die from poisoning as often.
As you know, your sense of taste isn’t just shades of grey with a few red flags of something that might harm you. Taste can also be used in order to reinforce behavior. Over generations, humans have adapted a pleasurable response to absorbing certain types of molecules, namely ones that have a great amount of energy. Lipids and sugars fit the bill.
I say lipids first because they are long hydrocarbon chains with many bonds that can be broken down for use by the Organism. Sugars are easy to break down but have less energy in each molecule. This is why fatty and sugary foods taste so good and also why they cause us to gain weight: they contain much more energy than we are expending. Not everyone loves sugary or fatty foods because our personal taste preferences are greatly affected by our experiences.
Taste, like all senses, can be converted into memory and is done so very quickly when something goes wrong. Let’s say you go to an All-You-Can-Eat buffet, because America, and you decide to chow down on some questionable looking meatloaf. Later that night, you find yourself kneeling over the toilet and thinking “I’ll never eat meatloaf again.” You are forming a very powerful connection between your memory of the taste of the meatloaf and the very unpleasant activity of vomiting. Meatloaf probably won’t be part of your appetite for quite some time. This is an evolutionary advantage: if eating something makes you sick, you don’t want to eat it again.
Eating isn’t all about the taste; texture matters too, sometimes even more! We perceive texture because of the touch sensors within our tongue and mouth. Although it doesn’t have to do with taste, I figured it would be fun to talk about why foods have certain textures.
Fruits are just ovaries made of sugars and other molecules to provide nutrition to the seeds within. Vegetables are the actual plant cells and plant cells have rigid cell walls which is why vegetables crunch. Meats are similar among similar animals: fish live in water and don’t require much power from each muscle movement; chicken and other poultry is technically just an evolved form of dinosaur meat; and mammal meat is usually fairly stringy much like our own muscles.
We all need to eat to live, some of us live to eat. Regardless of whether you are into fancy multi-course meals or just enjoy chowing down on trail mix, knowing how your sense of taste works can give you a greater appreciation for your food and why you enjoy it.