Sweet, Sour, Salt and Bitter

Using our sense of taste makes us so happy!
We celebrate our holidays with foods that taste good to us, some sweet, some salty,
some even slightly sour or bitter, but mix these flavours together and our enjoyment increases.
As soon as, even before, we are born we already love sweet flavours which makes sense because sugars are the chemicals we need for energy and growth.
We are born disliking bitterness, a protection against eating poisons.
Then we learn to recognize sour and salty flavours as growing babies.
We can even keep many tastes in our memory and know when food is spoiled (and not to be eaten) if the taste does not match what we remember.

sweetsoursaltbitter

Did you know that you can only taste 4 flavours with your tongue?
Those flavours are: sweet, sour, salt and bitter.
(Or 5 if you believe the latest discovery of a flavor named 'Umami').
All the other flavours you 'taste' or 'tasted' are a combination of these 4 flavours, or are tasted (smelled) with your nose!!
That is the reason why you can not enjoy your food when you have caught a cold.

True or not?

It is a common thought that you can taste the different types of flavours on different parts of your tongue.
There are scientist who say that that is not true.
0ne of the most dubious "facts" about taste - and one that is commonly reproduced in textbooks - is the oft-cited but misleading "tongue map" showing large regional differences in sensitivity across the human tongue.
These maps indicate that sweetness is detected by taste buds on the tip of the tongue, sourness on the sides, bitterness at the back and saltiness along the edges.
Taste researchers have known for many years that these tongue maps are wrong.
The maps arose early in the 20th century as a result of a misinterpretation of research reported in the late 1800's, and they have been almost impossible to purge from the literature.
In reality, all qualities of taste can be elicited from all the regions of the tongue that contain taste buds.
At present, we have no evidence that any kind of spatial segregation of sensitivities contributes to the neural representation of taste quality although there are some slight differences in sensitivity across the tongue and palate, especially rodents.

tongue map

Now find out for yourself.

You need cups with different flavours, like: lemon juice, vinegar, sugar and shock tarts (or strong coffee, onion juice, tonic) in separate cups.
Label the bottom of each cup to indicate the contents.
On the sides of the cups, write A, B, C or D and place on a table facing the recorder.

Look at the 'tongue map' above.

The subject (or taster) should be blindfolded or close the eyes.
Use a clean Q-tip or cotton stick each time!
And let the taster rinse the mouth with water in between different flavors.

The experimenter will dip the end into one of the cups with the liquid content and place on different areas of the student's tongue.
The shock tarts should be placed in the subject's hand and they will place it on different areas of their tongue.
When you use the fluids than you can use the cotton sticks.
Each time the tongue is touched, the student should be asked to identify the taste sensation that they experienced.
Let the student drink some water in between the different flavors.

Each response should be noted by the recorder on the tongue map.
Once all students within the group have completed the task, allow students to conduct the experiment again.
This time the blindfold should not be included. The experiment should be conducted a third time.
This time students will hold their nose and complete each step of the experiment.
When the experiment is completed, students should review their individual responses and then compare them with the other students in their group.
Each group will write their overall results and compare with the rest of the class.



What do you think?
Is the tongue map fiction or reality?
"No one has a right to consume happiness without producing it."

© - Site Seeing - Sonny, Lotje, Laurette en Femke, The Netherlands 2006