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Five facts about smell

Alice Bartlett
November 02, 2013
620

Five facts about smell

Five facts about smell squeezed in to 10 minutes.

I had so much fun giving this talk. There is a mistake on slide 15 which I have left in for the lols.

Alice Bartlett

November 02, 2013
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Transcript

  1. 2. 1.2% of people do not have a sense of

    smell*. [Gilbert and Wysocki 1987]
  2. 3. Some smells are easily detectable to humans even at

    very low concentrations. Nobody knows why.
  3. FIVE SMELLY SMELLS: ! 1. GRAPEFRUIT JUICE 2. CORK ODOUR

    3. BUTTER 4. PEPPERONI 5. STRAWBERRY [Ohloff 1990]
  4. FIVE SMELLY SMELLS: ! Nobody knows why the human nose

    is better at detecting these compounds but it really is.
  5. Comparison of detection thresholds in water: ! Limonene: 10ppb 

    ! Menthene-8-thiol: 0.00001ppb (grapefruit) Demole E., P Enggist and G. Ohloff, Helv. Chem. Acta, 65, 1785-1794 (1982) (limonene)Fazzalari, F A., editor, Compilation of Odor and Taste Threshold Data, ASTM Data Series DS 48A (1978)
  6. SEVEN PRIMARY ODOURS: ! 1. Musky (moth balls) 2. Floral

    (roses) 3. Pepperminty 4. Ethereal (detergent) 5. Pungent (vinegar) 6. Putrid (bad eggs) [Amoore et al. 1964]
  7. We don’t know how this reaction works. There are two

    theories and neither have been disproven
  8. BUT

  9. This model has also not been able to predict any

    smells from looking at the shape, which you would expect it to be able to.
  10. “Vibration Theory” states that it is not the shape but

    the vibration pattern of the molecule that determines it’s odour