|MadSci Network: General Biology|
This is a good question.
Normally, smell is more important than taste because the food you eat contains many chemicals that will stimulate the sense cells in your nose. However, you are only able to smell certain types of chemicals. If you taste a pure compound (such as PROP), there is a good chance you may not be able to smell it. Propylthiouracil is being used by some scientists to learn more about our sense of taste. It makes no sense to use a chemical that stimulates the sense cells in your nose when you are trying to isolate the effects on the sense cells in the tongue.
I have not been able to find out much about the chemistry of PROP on the internet, but Dr. Bartoshuk, an expert at Yale on the taste senses, writes, "PROP can have a sulfurous odor if it has been sitting on the shelf too long. In general, it has little odor. "
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