From fragrant to popcorn: US scientists identify 10 categories for smells

 

Forget the unique aroma of fresh coffee, wild lavender or cut grass, according to US scientists there are just 10 basic smells.

In claims that would confound French perfumers and will prove controversial, a new study has reduced the thousands of odours humans can detect to a handful of categories.

According to Professors Jason Castro, of Bates College, and Chakra Chennubhotla, from the University of Pittsburgh, some 144 smells they tested could be grouped into 10 categories - including “fragrant, popcorn” and “chemical”.

The scientists told the PLoS One journal that the new categories allowed people to build smells and could lead to the ability to predict a smell based on its chemical structure.

Working with a 1985 list of odour “character profiles”, researchers applied mathematical methods to simplify the olfactory information.

They described it as similar to compressing digital audio or image files. “You have these 10 basic categories because they reflect important attributes about the world - danger, food and so on,” Prof Castro said. “If you know these basic categories, then you can start to think about building smells.”

He added: “It's an open question how many fundamental types of odour qualities there are. This is in striking contrast to olfaction's 'sister sense', taste, where we know that five basic qualities seem to organise sensations.”

He added that the theory would need to be tested on more complex aromas - such as perfumes - and that natural scents were likely to be a “complex blend” of the 10 categories.

The science of smelling has long confounded experts with many claiming it still remains a mystery. It was only in 2004 that it was discovered how the brain recognises and remembers thousands of different odours thanks to a large gene family that controls specialised protein receptors in the nose.

Prof Richard Axel, of Columbia University, and Prof Linda Buck, of Fred Hutchinson Cancer Research Center in Seattle, were awarded the Nobel Prize for their discovery.

The categories

1 Fragrant

2 Woody/resinous

3 Fruity (non-citrus)

4 Chemical

5 Minty/peppermint

6 Sweet

7 Popcorn

8 Lemon

9 Pungent

10 Decayed

Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
Arts and Entertainment
The Bach Choir has been crowned the inaugural winner of Sky Arts’ show The Great Culture Quiz
arts + ents140-year-old choir declared winner of Sky Arts' 'The Great Culture Quiz'
Life and Style
food + drink
News
i100
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Finance Director

£65000 - £80000 per annum: Recruitment Genius: Finance Director required to jo...

Recruitment Genius: Medico-Legal Assistant

£15000 - £25000 per annum: Recruitment Genius: This is a unique opportunity fo...

Ashdown Group: (PHP / Python) - Global Media firm

£50000 per annum + 26 days holiday,pension: Ashdown Group: A highly successful...

The Jenrick Group: Quality Inspector

£27000 per annum + pension + holidays: The Jenrick Group: A Quality Technician...

Day In a Page

Homeless Veterans appeal: 'You look for someone who's an inspiration and try to be like them'

Homeless Veterans appeal

In 2010, Sgt Gary Jamieson stepped on an IED in Afghanistan and lost his legs and an arm. He reveals what, and who, helped him to make a remarkable recovery
Could cannabis oil reverse the effects of cancer?

Could cannabis oil reverse effects of cancer?

As a film following six patients receiving the controversial treatment is released, Kate Hilpern uncovers a very slippery issue
The Interview movie review: You can't see Seth Rogen and James Franco's Kim Jong Un assassination film, but you can read about it here

The Interview movie review

You can't see Seth Rogen and James Franco's Kim Jong Un assassination film, but you can read about it here
Serial mania has propelled podcasts into the cultural mainstream

How podcasts became mainstream

People have consumed gripping armchair investigation Serial with a relish typically reserved for box-set binges
Jesus Christ has become an unlikely pin-up for hipster marketing companies

Jesus Christ has become an unlikely pin-up

Kevin Lee Light, aka "Jesus", is the newest client of creative agency Mother while rival agency Anomaly has launched Sexy Jesus, depicting the Messiah in a series of Athena-style poses
Rosetta space mission voted most important scientific breakthrough of 2014

A memorable year for science – if not for mice

The most important scientific breakthroughs of 2014
Christmas cocktails to make you merry: From eggnog to Brown Betty and Rum Bumpo

Christmas cocktails to make you merry

Mulled wine is an essential seasonal treat. But now drinkers are rediscovering other traditional festive tipples. Angela Clutton raises a glass to Christmas cocktails
5 best activity trackers

Fitness technology: 5 best activity trackers

Up the ante in your regimen and change the habits of a lifetime with this wearable tech
Paul Scholes column: It's a little-known fact, but I have played one of the seven dwarves

Paul Scholes column

It's a little-known fact, but I have played one of the seven dwarves
Fifa's travelling circus once again steals limelight from real stars

Fifa's travelling circus once again steals limelight from real stars

Club World Cup kicked into the long grass by the continued farce surrounding Blatter, Garcia, Russia and Qatar
Frank Warren column: 2014 – boxing is back and winning new fans

Frank Warren: Boxing is back and winning new fans

2014 proves it's now one of sport's biggest hitters again
Jeb Bush vs Hillary Clinton: The power dynamics of the two first families

Jeb Bush vs Hillary Clinton

Karen Tumulty explores the power dynamics of the two first families
Stockholm is rivalling Silicon Valley with a hotbed of technology start-ups

Stockholm is rivalling Silicon Valley

The Swedish capital is home to two of the most popular video games in the world, as well as thousands of technology start-ups worth hundreds of millions of pounds – and it's all happened since 2009
Did Japanese workers really get their symbols mixed up and display Santa on a crucifix?

Crucified Santa: Urban myth refuses to die

The story goes that Japanese store workers created a life-size effigy of a smiling "Father Kurisumasu" attached to a facsimile of Our Lord's final instrument of torture
Jennifer Saunders and Kate Moss join David Walliams on set for TV adaptation of The Boy in the Dress

The Boy in the Dress: On set with the stars

Walliams' story about a boy who goes to school in a dress will be shown this Christmas