Beautiful colorimeter lets you take snapshots of smells

Researchers at the University of Illinois, Urbana-Champaign have developed a way to compare aromas visually using specially developed inks.

Kenneth Suslick and his colleagues used tiny squares of polymer film that hold 36 drops of carefully designed dyes. These pigments change colour when exposed to various chemicals. The result is a cheap system for detecting very low concentrations of gaseous compounds. The cards can be used like a physicist's radiation dose badge to alert lab workers when they have been exposed to toxic gases.


As shown above, the cards can be used to give each particular compound a unique fingerprint. This means that the system can also be used to detect subtle differences in complex aromas, such as coffee.

i-7dd8ff463f9b108d9b533615f0fd7a3a-coffee difference maps_s.jpg

Suslick's seventeen-year-old son Benjamin carried out the research into coffee aromas, showing how the colorimeters could be used as a quick and reliable way to detect burned or spoiled batches in the food industry.

I'd love to know what other smells looked like. A giant wall poster showing a colour map of Chanel No 5 or jasmine would make a great talking point, and look gorgeous too.

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Perfumistas of the world are also dying to see a visual representation of some of the classics. What a cool blog post!

By Kristy Victoria (not verified) on 19 Feb 2010 #permalink

So what are the eigensmells of this 36-dimensional space?

I guess you can't answer that if it's not an operator, but I guess you could map between this and peoples notes on oenology and determine the principle components of wine taste/odor.

Dr. Suslick has been exploring this technology for about a decade. Given the low cost and large number of potential uses for it, it's a headscratcher to me that it isn't an established technology by now. For example, freshness labels for food in the store, freshness test strips for consumers with age-related anosmia ("is my milk sour?"), or detection of counterfeit pharmaceuticals.

What a fantastic technique. I wonder what the repeatibility and precision is.


Maybe not eigensmells (as such) but it must be ripe (sorry!) for Principal Component Analysis (GIYF) and for training neural networks.

absolutely brilliant and well done to 17yr old Benjamin. Over time the picture representations of aroma would give people the ability to triangulate flavours they like and dislike in coffee's.

Love it, am on it. No doubt the third wave or the fourth rail or what ever the cool people r called now will soon be 2

Not new but new to me the coffee beta testing will be most interesting and yes repeatability will be more than interesting........critical