The B.O. wheel

The state of the universe.
March 25 2009 3:20 PM

The B.O. Wheel

1_123125_2093564_2208788_2213739_090225_sci_wheelex

An "aroma wheel" is a popular visual scheme for diagramming the range of smells that characterize a particular food or beverage. A well-known example is the wine aroma wheel, developed in 1984 by University of California-Davis chemist Ann Noble. It is laid out like a dartboard, with broad flavor categories (e.g., "fruity") near the center and specific examples of that category (e.g., "strawberry") on the outer ring. Connoisseurs have built aroma wheels for beer, coffee, brandy, cheese, chocolate, roast beef, and even sewage—but perhaps never for body odor.

Advertisement

Until now. At the center of the B.O. universe sits its dominant aroma—pure locker-room sweat. From there, the tree branches by gender, reflecting the differences between male and female armpits. Male armpits have more apocrine sweat glands and contain more microbes from the genus Corynebacterium, which manufacture some of the strongest odors. Men also perspire five times as much as women, and their sweat is more sugary.

In January, a Swiss fragrance firm concluded after years of study that female perspiration smells like grapefruit, passion fruit, and onion, while male sweat smells more cheesy, rancid, and animalic. Several years earlier, the same firm had analyzed male sweat and detected these flavor notes: chicken broth, butter, vinegar, onion, and grapefruit. The presence of grapefruit and onion—the scent of a woman—in male sweat gives the lie to the notion that men's B.O. is from Mars while women's is from Venus. For this reason, the B.O. wheel expresses gender differences on a gradient.

Diet also affects body odor. A 2007 study by the Monell Center showed that volatiles derived from turmeric, mint, and garlic can appear in sweat. Other foods whose by-products may be released in B.O. include onion, chili, vinegar, blue cheese, cabbage, radish, fermented milk products, and fish. These foods are condensed into groups on the B.O. wheel.

Other wheel descriptors include "goaty" (named for a gamey secretion of horny male goats) and "boar taint" (the steroid androstenone, also present in boar saliva). These are well-known odorous compounds in armpit sweat. Telephone and e-mail interviews with body- odor and fragrance experts yielded more flavors: wet dog, spicy-cumin, alcohol, and gasoline. To build the B.O. wheel, similar flavors were grouped in accord with existing aroma wheels. The B.O. wheel does not claim to describe all extant body odors.

TODAY IN SLATE

Culturebox

The End of Pregnancy

And the inevitable rise of the artificial womb.

Doctor Tests Positive for Ebola in New York City

How a Company You’ve Never Heard of Took Control of the Entire Porn Industry

The Hot New Strategy for Desperate Democrats

Blame China for everything.

The Questions That Michael Brown’s Autopsies Can’t Answer

Foreigners

Kiev Used to Be an Easygoing Place

Now it’s descending into madness.

Technology

Don’t Just Sit There

How to be more productive during your commute.

There Has Never Been a Comic Book Character Like John Constantine

Which Came First, the Word Chicken or the Word Egg?

  News & Politics
The Slate Quiz
Oct. 24 2014 12:10 AM Play the Slate News Quiz With Jeopardy! superchampion Ken Jennings.
  Business
Moneybox
Oct. 23 2014 5:53 PM Amazon Investors Suddenly Bearish on Losing Money
  Life
Outward
Oct. 23 2014 5:08 PM Why Is an Obscure 1968 Documentary in the Opening Credits of Transparent?
  Double X
The XX Factor
Oct. 23 2014 11:33 AM Watch Little Princesses Curse for the Feminist Cause
  Slate Plus
Working
Oct. 23 2014 11:28 AM Slate’s Working Podcast: Episode 2 Transcript Read what David Plotz asked Dr. Meri Kolbrener about her workday.
  Arts
Brow Beat
Oct. 23 2014 6:55 PM A Goodfellas Actor Sued The Simpsons for Stealing His Likeness. Does He Have a Case?
  Technology
Technology
Oct. 23 2014 11:47 PM Don’t Just Sit There How to be more productive during your commute.
  Health & Science
Bad Astronomy
Oct. 24 2014 7:00 AM Gallery: The Partial Solar Eclipse of October 2014
  Sports
Sports Nut
Oct. 20 2014 5:09 PM Keepaway, on Three. Ready—Break! On his record-breaking touchdown pass, Peyton Manning couldn’t even leave the celebration to chance.