Chemical magic in the mouth

Nov 10, 2008
Fruit
Scientists report that mouth bacteria are responsible for creating the distinctive flavors of certain foods, including some fruits and vegetables. Credit: Wikipedia

Scientists in Switzerland are reporting that bacteria in the human mouth play a role in creating the distinctive flavors of certain foods. They found that these bacteria actually produce food odors from odorless components of food, allowing people to fully savor fruits and vegetables. Their study is scheduled for the November 12 edition of the ACS bi-weekly Journal of Agricultural and Food Chemistry.

In the study, Christian Starkenmann and colleagues point out that some fruits and vegetables release characteristic odors only after being swallowed. While scientists have previously reported that volatile compounds produced from precursors found in these foods are responsible for this 'retroaromatic' effect, the details of this transformation were not understood.

To fill that knowledge gap, the scientists performed sensory tests on 30 trained panelists to evaluate the odor intensity of volatile compounds – known as thiols – that are released from odorless sulfur compounds found naturally in grapes, onions, and bell peppers. When given samples of the odorless compounds, it took participants 20 to 30 seconds to perceive the aroma of the thiols – and this perception persisted for three minutes.

The researchers also determined that the odorless compounds are transformed into the thiols by anaerobic bacteria residing in the mouth – causing the characteristic 'retroaromatic' effect. "The mouth acts as a reactor, adding another dimension to odor perceptions," they explain. However, the authors conclude, it is saliva's ability to trap these free thiols that helps modulate the long-lasting flavors.

Citation: "Olfactory Perception of Cysteine – S-Conjugates from Fruits and Vegetables" dx.doi.org/10.1021/jf801873h

Source: ACS

Explore further: Repeated self-healing now possible in composite materials

add to favorites email to friend print save as pdf

Related Stories

Visions of 1964 World's Fair didn't all come true

7 hours ago

Video phone calls? Yeah, we do that. Asking computers for information? Sure, several times a day. Colonies on the moon and jet packs as a mode of everyday transportation. OK, maybe not.

Instagram photo-sharing service goes down

7 hours ago

Popular photo-sharing site Instagram was not working Saturday, as frustrated users quickly turned to social network Twitter and other web sites to share their complaints.

Power arm band for wearables harvests body heat

12 hours ago

(Phys.org) —A group of Korean researchers have turned their focus on supplying a reliable, efficient power source for wearables. Professor Byung Jin Cho of the Korea Advanced Institute of Science and Technology ...

Amazon 'to release smartphone later this year'

12 hours ago

Amazon is preparing to release a smartphone in the second half of 2014, thrusting itself into a market already crowded with Apple and Samsung models, The Wall Street Journal reported.

Recommended for you

Research offers 'promise' of improved food safety

17 hours ago

The issue of food safety has rocketed up the political agenda in recent years but despite huge improvements, some concerns and problems still persist. Fears about our food are moving away from issues about ...

Metals go from strength to strength

17 hours ago

To the human hand, metal feels hard, but at the nanoscale it is surprisingly malleable. Push a lump of metal with brute force through a right-angle mould or die, and while it might look much the same to the ...

Chemists achieve molecular first

18 hours ago

(Phys.org) —Chemists from Trinity College Dublin have achieved a long-pursued molecular first by interlocking three molecules through a single point. Developing interlocked molecules is one of the greatest ...

User comments : 0

More news stories

Chemists achieve molecular first

(Phys.org) —Chemists from Trinity College Dublin have achieved a long-pursued molecular first by interlocking three molecules through a single point. Developing interlocked molecules is one of the greatest ...

Metals go from strength to strength

To the human hand, metal feels hard, but at the nanoscale it is surprisingly malleable. Push a lump of metal with brute force through a right-angle mould or die, and while it might look much the same to the ...

Low Vitamin D may not be a culprit in menopause symptoms

A new study from the Women's Health Initiative (WHI) shows no significant connection between vitamin D levels and menopause symptoms. The study was published online today in Menopause, the journal of The North American Menopa ...

Astronomers: 'Tilt-a-worlds' could harbor life

A fluctuating tilt in a planet's orbit does not preclude the possibility of life, according to new research by astronomers at the University of Washington, Utah's Weber State University and NASA. In fact, ...