Expert: Dana Krempels, Ph.D. - 7/29/2008

Question
Hi
-Do human have the same biochemical system in our body, that we produce the same signal,flavour and respond from tasty food alike?

-Why do human seem to have the same agreement on "tasty" and "aweful" food? since human like to hold culinary contest? and snack are indeed tastier compared to others
-How did human biochemistry system come to a agreement over "tasty" and "awful"?since most people find egg yolk awful and "hard to savor"?
-Is there no way to define "tasty" food and "awful" food? What is a "tasty" food?
-Why are some food seem to be tastier than other food? Does "tasty food" really exist? Is there really "properties of taste" that define "delicious"?
-If all human follow the same taste properties and agree on the "properties of taste", do all human share the same biochemical system?
-Are human more attracted to "tasty food" because it is nutritious from evolution?

-How is it possible for me to know whether do I taste normally? as all I can prove is, I am able to "tell the difference between taste", but how I know I what I taste is "sweet"?

Answer
Dear Rambo,

The answers to the questions you ask here are exactly the same as the ones you asked about vision and smell.  Yes, humans differ biochemically.  But taste, like vision and smell, is a psychophysical sensation, and there is no way we can know if what one person tastes is exactly like what another person tastes.  In all probability, it is not the same.

We have evolved in different parts of the world where there are different food sources available. Much of what we learn as "tasty" has to do with early childhood experiences that are inextricably linked to culture, and sometimes with evolution.

For example, people in tropical climates learned to use spices to flavor their foods. Why did they do this?  Proximally, because they enjoyed the taste.  But it also turns out that many spices have anti-bacterial properties.  So it is actually beneficial to enjoy and eat spices if you live in a climate where food is prone to spoil.  

Populations of humans that evolved in cold climates had less trouble with spoilage, and so are less likely to have spicy foods.  But is this nature or nurture? It would be very difficult to find out, since human experimentation is difficult to perform ethically.  :)

Hope that helps.

Dana