There is no denying that the human body is a rather incredible collection of organs and abilities, which have allowed us to become the most dominant species on the planet. Some of the most important tools that have led to humanity’s rise are our senses – sight, smell, hearing, touch and taste.
While many other species possess these senses – and in many cases, the senses are more developed or specialized than in humans – humans use them in exquisite combinations to experience the world around us. The sense that is overlooked most often, however, is our ability to taste things. Obviously, food is a huge part of our daily life, but how often do you actually think about the phenomenal range of tastes in the world? More specifically, don’t you wonder how we are able to taste things at all?
Short answer: Our brain decodes the basic taste profile of food, and combines that with olfactory information to create a “taste”. However, the rest of the story is even more delectable.
The Truth About Taste
When you break down taste in its simplest terms, it is an equation of combinations. Essentially, there are four core taste categories that we detect in the things we eat – sweet, salty, bitter and sour. Essentially, these four base categories can describe almost everything we consume. These sensitivities to taste developed over millions of years as early humans and earlier ancestors were determining which foods were safe to eat. Bitter and sour-tasting foods were approached with much more caution, as they were often poisonous, toxic, or decaying. Sweet and salty foods, however, were normally a sign that the food was rich in nutrients and unlikely to be harmful.
Over thousands of generations, our sense of taste continued to evolve, and in the past century, a new taste profile has been popularized, called umami. This is the taste associated with something that is meaty, savory or rich. Now, at this point, taste seems like a rather simple equation. A dash of salty, some sweet, and a light sprinkling of sour might make for a great cocktail, but that is simply the taste, which does not explain our fascination with flavor.
Before we get into that, however, we should explain the basic science of taste. It all starts in our mouth, namely on the taste buds of the tongue. Many people think that the taste buds are the small bumps that you can see on your tongue, a few hundred in all, but humans actually possess anywhere from 2,000-10,000 taste buds, and these are located on those bumps, which do have a name – taste papillae. These papillae are located just under the mucus membrane of the tongue, and help to increase the surface area of the tongue by 2-3x, ensuring that all food can be properly analyzed and identified before we swallow it. There are four main types of papillae, some of which are incredibly dense with taste buds. On each taste bud, there is between 10-50 sensory cells, which is where all of the magic happens!
These sensory receptor cells that can be affected by different substances; more specifically, they alter the protein formation on the wall of that cell. When a particular type of food is eaten, say a fresh piece of cantaloupe with fructose in it, the taste buds will have certain sensory cells that activate, starting the chain reaction that will eventually deliver that information to the brain.
Uniquely, taste is our one sense that is highly dependent on the others, as well as our own memory and experience. When we eat something, such as a chocolate-chip cookie, we immediately begin breaking down the content of the cookie with our saliva, instantly telling our brain that we are eating something sweet. However, we wouldn’t be able to recognize it as chocolate unless we use another sense – smell!
Smell and taste are intimately linked, and the smell of our food is actually what provides us with the specific information on the flavor of food. This is why having a cold makes it so difficult for people to enjoy their meals; when you are congested, you are unable to smell properly, making your food essentially tasteless. You can detect when something is hot, salty, sour or sweet, but there is no complementary flavor, since your olfactory sense is compromised.
When your taste buds and nose are in proper working order, the taste and nerve messages received while eating travel through the brain, up to the facial nerve and the glossopharyngeal nerve, before moving to the gustatory cortex. Essentially, we think that taste is generated in our mouth, when in fact, the final “flavor” of something is determined when taste, nerve and smell messages all link up in the brain!
How Can Our Tastes Change?
No two people have the same orientation and number of taste buds; in effect, the tongue is about as unique as a fingerprint, and as such, no two people have the same powers of taste. Some people are considered “supertasters”, who have up to 25% more papillae on average, making them extremely sensitive to flavors and tastes. This might explain the “picky eaters” in your life. Other people have far fewer taste buds, particularly as they get older, when taste buds permanently die.
Certain foods have the ability to mess with our taste buds too! There are certain compounds found in herbs, fruits and vegetables around the world that can trick our mouth into thinking that savory is sour, or bitter is sweet, making for a very confusing meal!
Most interestingly, the way that we taste things and our personal preference for certain foods can be affected by genetics, as well as personal experience – yet another battle of nature vs. nurture. Certain genetic predispositions to taste, such as cilantro or Japanese nato, is based on whether we possess certain gene variants. If one gene variant increases the sensitivity to bitterness, people may be less likely to enjoy the flavor of broccoli or seaweed, whereas other people have a low genetic sensitivity to sweetness, so eating an entire chocolate cake doesn’t faze them!
Finally, the associations that we have with food can be a strong factor behind how we taste something. We combine sight, smell, texture, taste and color to create our conception of what we are eating, so if any of those elements are changed, say a carrot that doesn’t have that characteristic crunch, it will seem as though the flavor is off. All of our senses engage in the process of eating and taste formulation, so if you want to train your taste buds in a new way, it might take a bit of effort!
- How Does Our Sense Of Taste Work? – National Center for Biotechnology Information (NCBI)
- A Matter of Taste – Brain Facts
- The Science Behind How We Taste – Webmd