Is most of taste really smell?

Well, it depends on how you define the terms "taste" and "smell." The way most people use "taste," to mean the sensations experienced when eating a food or drinking a beverage, smell is definitely a large portion of the experience. If, however, you define the terms "taste" and "smell" more scientifically, so that taste refers to the sensations elicited by stimulation of the taste receptor cells and smell refers to the stimulation of olfactory neuron, then these are independent senses, both of which play an important role in the experiencing of foods and beverages. A more scientifically accurate statement would be that "Most of flavor is smell," where flavor is defined as the combination of sensations experienced when eating or drinking, especially, taste, smell, and chemesthesis.

Why can't you taste anything when you have a cold?

As I explained in the answer above, this depends a bit on the way you define "taste." When you have a cold, you tend to get congested (a stuffed-up nose). When this happens, air stops flowing past the olfactory receptors, which means that odor compounds cannot reach them and your sense of smell will not work. So, when you have a cold, your sense of smell stops working. Your sense of taste, which arises from the stimulation of taste receptor cells is usually unaffected, but since you can't smell, the flavor of foods and beverages is definitely altered.

Are there four basic tastes?

You may have been taught that all we “really taste” is sweet, sour, salty, and bitter, but this is in fact not an established fact. There are many prominent researchers who believe in the existence of a fifth “basic taste,” called “umami.” This taste is associated with the taste of MSG (monosodium glutamate, the primary ingredient in AccentTM) and is described as a “brothy” or “savory” taste. There are still others who believe that the entire concept of basic tastes is flawed and feel that the evidence supporting this idea is based more upon language limitations than on perceptual or physiological ones. For a more extensive treatment of the existence of basic tastes, you might want to take a look at: Delwiche, J. F. (1996). Are there 'basic' tastes? Trends in Food Science and Technology, Vol. 7, pp. 411-415.

Is there a fifth basic taste?

There are many prominent researchers who believe in the existence of a fifth “basic taste,” called “umami.” This taste is associated with the taste of MSG (monosodium glutamate, the primary ingredient in Accent) and is described as a “brothy” or “savory” taste. Although many  researchers initially argued that its unique properties arose from odor or mouthfeel characteristics, it is now widely accepted as a true gustatory stimulus.

Is the tongue map true?

mapThis is, in fact, a complete and utter falsity. It is a myth. In fact, you can taste all taste compounds everywhere on your tongue, as long as you stimulate taste receptor cells. If you want to test this yourself, put salt on the tip of your tongue. You will see that you clearly taste saltiness immediately and do not need to wait for the stimulus to diffuse to other areas of your tongue. You can demonstrate the same thing for sourness using one of those intensely sour candies that are coated with tartaric acid, like Sour Patch Kids or Cry Babies or some such, the same thing for sweetness by putting sugar on the tip of your tongue, and the same thing for bitterness by placing freeze-dried decaffeinated coffee crystals on the tip of your tongue.

Is smell the best sense at triggering memory?

Known as the “Proust effect,” certain odors can evoke involuntary memories.  Several studies have looked at this phenomenon (see this study and this study for examples) versus stimuli from other modalities, especially vision and hearing. Results across investigation have been somewhat inconsistent, but odors do not seem to trigger more accurate recall. Some evidence suggests that odor-evoked memories are emotionally charged, but this has proven difficult to capture in the laboratory. It is likely that such an emotional charge is linked to very specific odors and events, unique to each individual, making it difficult to demonstrate empirically what many have experienced.

What is a pheromone?

The exact definition of a pheromone is an issue that is still debated. A deceptively simple definition is that it is an externally secreted chemical that sends information from one organism to other members of the same species. But organisms secrete an abundance of chemicals. What makes one chemical an odor and another a pheromone? Many say that a chemical must elicit a behavioral response in other organisms to be considered a pheromone. Others say that it must be detected by the vomeronasal organ, a specialized system similar to the olfactory system, found in many animals. Still others say that both must be true. The clearest examples of pheromones are found in insects, where a chemical secreted by the female when she is ready to mate can attract the male of the species from great distances.

Does perfume with pheromones in it attract the opposite sex?

To date, there has been no reliable scientific evidence from independent sources to indicate that the use of pheromone-containing perfumes is effective at attracting members of the opposite sex.

Still have questions?

If you have a specific question that isn't covered by these Basics, and is NOT clinical in nature, feel free to try writing Dr. Delwiche through our Contact Us page. Don't be surprised if it takes her a while to respond. While she does her best to respond to all inquiries related to her area of her expertise, such responses are unpaid volunteer contributions. Questions of a clinical nature will be ignored.Please note: Dr. Delwiche is not a medical doctor and does not do clinical research. Scant research has been done in this area and almost no treatments exist. If you have a question regarding a problem with taste or smell, you may want to visit one of the following sites:
NIDCD Taste and Smell
Taste and Smell Disorders Clinic in Texas
University of Connecticut Taste and Smell Clinic
Monell-Jefferson Taste and Smell Clinic
Taste and Smell Center at the University of Pennsylvania
Taste and Smell Clinic in D.C.
Smell and Taste Treatment and Research Foundation, Ltd