The aroma of foods could become
a new weapon in the battle of the bulge
by quenching the sensation of hunger.
Credit: Wikimedia Commons, Jon Sullivan
A real possibility exists for developing a new generation of
foods that make people feel full by releasing anti-hunger aromas during
chewing.
Scientists in the Netherlands are reporting that foods could fight the global epidemic of
obesity with aromas that quench hunger and prevent people from
overeating. Their article appears in ACS' Journal of Agricultural and Food Chemistry: "Retronasal Aroma Release and Satiation: A Review".
Rianne Ruijschop and colleagues note that scientists long have tried
to develop tasty foods that trigger or boost the feeling of fullness.
Until recently, that research focused on food's effects in stomach
after people swallow it.
Efforts now have expanded to include foods
that release hunger-quenching aromas during chewing. Molecules that
make up a food's aroma apparently do so by activating areas of the
brain that signal fullness.
Their analysis found that aroma release during chewing does
contribute to the feeling of fullness and possibly to consumers'
decisions to stop eating. The report cites several possible
applications, including developing foods that release more aroma during
chewing or developing aromas that have a more powerful effect in
triggering feelings of fullness.
Rosemary, thyme, clove, and mint are well-known spices that are emerging as organic
agriculture's key weapons against insect pests.
Scientists in Canada
are reporting new research on these so-called "essential oil
pesticides" or "killer spices." These pesticides have added to the
crop-preserving arsenal of organic growers and offer several advantages
over their counterparts -- they're readily available and don't require
lots of regulatory approval.
And they're safer for gardeners and farm workers, who are at high risk for pesticide exposure.
Murray Isman, Ph.D., of the University of British Columbia is developing these pesticides.
So, just what is it exactly about these spices that allow them to work their magic outside the kitchen? Here's Dr. Isman again:
"It
turns out that some of these oils and some of the chemical constituents
in the oils are neurotoxic to many types of insects. At least one of
their actions, and we're not certain about all of their actions, one of
their actions is they interfere with a neuromodulator in insects called
octopamine. It's sort of an internal valium for insects, it sort of
calms them down so their nervous systems
don't get overstimulated by external stimuli. If you remove that octopamine, which is what
some of these oils do, they get hyperexcited and eventually die."
These pesticides, usually a combination of spices diluted with
water, have added to the crop-preserving arsenal of organic growers and
offer several advantages over their counterparts. First, they are
readily available and don't require lots of regulatory approval. Also,
insects exposed to the spices are less likely to evolve resistance to
the toxins. And, they're safer for farm workers, who are at high risk
for pesticide exposure.
"Some of these oils, as some other people have mentioned, are very good antimicrobials,
so they could be very useful against food spoilage organisms, for example. They are useful
against certain plant pathogenic fungi and bacteria, and they do have this phytotoxic effect
on plants, so at high concentrations they can be used as natural herbicides."
People are unconsciously fairer and more generous when they are in
clean-smelling environments.
A Brigham Young University professor's research found a dramatic improvement in ethical behavior with just a few spritzes of citrus-scented Windex.
The researchers see implications for
workplaces, retail stores and other organizations that have relied on
traditional surveillance and security measures to enforce rules.
"Companies
often employ heavy-handed interventions to regulate conduct, but they
can be costly or oppressive," said Liljenquist, whose office smells
quite average. "This is a very simple, unobtrusive way to promote
ethical behavior."
Perhaps the findings could be applied at home,
too, Liljenquist said with a smile. "Could be that getting our kids to
clean up their rooms might help them clean up their acts, too."
The
study titled "The Smell of Virtue" was unusually simple and conclusive.
Participants engaged in several tasks, the only difference being that
some worked in unscented rooms, while others worked in rooms freshly
spritzed with Windex.
The first experiment evaluated fairness. As
a test of whether clean scents would enhance reciprocity, participants
played a classic "trust game." Subjects received $12 of real money
(allegedly sent by an anonymous partner in another room). They had to
decide how much of it to either keep or return to their partners who
had trusted them to divide it fairly. Subjects in clean-scented rooms
were less likely to exploit the trust of their partners, returning a
significantly higher share of the money.
· The average amount of
cash given back by the people in the "normal" room was $2.81. But the
people in the clean-scented room gave back an average of $5.33.
The
second experiment evaluated whether clean scents would encourage
charitable behavior. Subjects indicated their interest in volunteering
with a campus organization for a Habitat for Humanity service project
and their interest in donating funds to the cause.
· Participants
surveyed in a Windex-ed room were significantly more interested in
volunteering (4.21 on a 7-point scale) than those in a normal room
(3.29).
· 22 percent of Windex-ed room participants said they'd
like to donate money, compared to only 6 percent of those in a normal
room.
Follow-up questions confirmed that participants didn't
notice the scent in the room and that their mood at the time of the
experiment didn't affect the outcomes.
Cleanliness is next to godliness? Was Granny right?
"Basically, our study
shows that morality and cleanliness can go hand-in-hand," said Galinsky
of the Kellogg School. "Researchers have known for years that scents
play an active role in reviving positive or negative experiences. Now,
our research can offer more insight into the links between people's
charitable actions and their surroundings."
While this study
examined the influence of the physical environment on morality, Zhong
and Liljenquist previously published work that demonstrated an intimate
link between morality and physical cleanliness. Their 2006 paper in Science reported that transgressions activated a desire to be physically cleansed.
Liljenquist
is now researching how perceptions of cleanliness shape our impressions
of people and organizations. "The data tell a compelling story about
how much we rely upon cleanliness cues to make a wide range of
judgments about others," she said.
Katie
Liljenquist is assistant professor of organizational leadership at BYU's
Marriott School of Management, and the lead author on the piece in a
forthcoming issue of Psychological Science. Co-authors are
Chen-Bo Zhong of the University of Toronto's Rotman School of
Management and Adam Galinsky of the Kellogg School of Management at
Northwestern University.
