I need help with a food science fair project...?

Question

me and a friend are doing a science fair project....we are taking 3 foods-onions, apples, and potatoes and giving them to some blindfolded people who also will have their nose plugged. we are trying to see exactly what makes you taste and if they can tell what each food is..by texture or by if they can really taste it. does anyone know any good sites for that? and also does anyone know where i can find a picture of a tounge and what part makes u taste what kinds of foods?

Answer 1

http://en.wikipedia.org/wiki/Taste is always a good place to start to get some basic ideas about your project.  Everything is usually explained simply, and then you can read the sources that they reference for more detailed information on the topic.

Something worth trying out:

There are five different "tastes" that are separate from what we smell.  Sweetness, bitterness, sourness, saltiness, and savoriness.  The last one (savoriness) is still in contention.  The flavor of a food is also affected by smell (which you're cutting out by plugging the nose here).

Picking items that have the same "taste" on the taste list, but different flavors (from smell) or textures will help you narrow down what people actually taste.  On the other hand, onions, apples, and potatoes all have different textures, flavors, and tastes.  

Try picking items that are both sweet, but have very different flavors (like strawberries versus apples).  Or try comparing oranges and lemons--very similar textures, and pretty similar flavors, but the sourness and sweetness are very different.  

This means that you can talk about controls on your experiment.  There are two controls you should talk about:

1.  It sounds stupid, but you should do the same test without the nose plug.  This would provide objective proof that it's the lack of smell (and not sight) that is causing people to have difficulty identifying certain similar foods.  It makes the project better scientifically.

2.  You can talk about controlling the texture, so that all of the foods feel the same, to prove that it wasn't feeling the foods that let people make the distinction between different ones.  Instead, it was the taste difference.  If you have to, make drinks or something with the consistency of a salsa out of the foods.  Toss them in a blender so that the texture is the same for all of them.  You could do this with pre-made drinks, too:  Can people tell that's it's orange juice or lemon juice?  In the same way, if you pick items with similar tastes but different textures, you can prove that people can identify foods by texture alone, without any taste or smell or flavor cues.

As a note, tongue maps are actually false.  They still show up all over the place, but they've been proven to not be true:  http://www.livescience.com/health/060829...