Re: Understanding Garlic

Notice when a human passes a restaurant with the kitchen fans running
full blast, a hunger response is triggered. I have often wondered why
restaurateurs never infuse the exhausts from their establishments with
garlic. When this human smells garlic, I WANT FOOD.
Several chemicals exist in a garlic bulb with out mixing. When the
mechanical action of an insect or animal attacking the plant, these
chemicals and enzymes mix together to give off the pungent odours and
flavours we all love. This is a defence mechanism.
There are a lot of different flavour profiles amongst garlic varieties.
Many garlic growers prefer to eat their garlic bulbs raw and favour small
bulbs grown on poor soil.

Farmer John

"maxine in ri" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

From Science News:
Week of June 4, 2005; Vol. 167, No. 23 , p. 357
Decoding Garlic's Pizzazz: Extract stimulates taste, temperature
receptors

Christen Brownlee

Despite garlic's widespread role in cooking-and in vampire
tales-scientists had long failed to explain the pungent plant's
burning taste. Now, a study of gustatory physiology suggests that raw
garlic's characteristic spiciness stems from its capacity to open
channels on nerve cells that react to both tastes and noxious
temperatures.

BURNING ISSUE. Raw garlic's prickly taste derives from allicin, a
chemical that may also have health benefits.
PhotoDisc

Researchers have identified a family of neuron receptors, known as
transient receptor potential (TRP) channels, that respond to diverse
triggers including touch, pain, and pheromones. At least six of these
receptors, a subset called thermoTRPs, react to both certain molecules
and unpleasant temperatures by permitting a flood of calcium ions to
enter nerve cells, which then fire.

Previous studies showed that thermoTRPs respond to several naturally
occurring flavor chemicals, such as capsaicin in hot peppers and
menthol, which gives peppermint its coolness. Although some
researchers have hypothesized that raw garlic also stimulates
thermoTRPs, Ardem Patapoutian of the Scripps Research Institute in La
Jolla, Calif., notes that no experiment had confirmed that conjecture.

To test whether the TRP channels are responsible for raw garlic's
strong flavor, Patapoutian's team used a kitchen garlic press and
more-sophisticated equipment to prepare extracts of both raw and baked
garlic purchased at groceries. The researchers added droplets of the
extracts to cultures of hamster cells that were genetically modified
to sport thermoTRPs on their membranes.

The team designed the experiment so that a cell would fluoresce when
calcium passed through its membrane. A glow would indicate that the
particular extract had activated the channels.

Patapoutian's team found that two types of thermoTRP channels,
designated TRPA1 and TRPV1, reacted to the extract from raw garlic but
not to the extract from baked garlic, which has a less pungent taste.

To investigate which chemical in raw garlic was responsible for
activating TRPA1 and TRPV1, the scientists compared the chemical
compositions of the extracts.

"We found that the major difference between the baked and raw garlic
extracts was that the raw extract contains allicin, but the baked does
not," says Patapoutian's Scripps colleague Lindsey Macpherson.
Allicin, a chemical well studied for its role in garlic's health
benefits, breaks down when garlic is heated. Further experiments with
hamster cells bearing thermoTRPs revealed that pure allicin opens the
calcium channels.

The researchers report their findings in the May 24 Current Biology.

The finding adds to a growing list of naturally occurring plant
products that stimulate thermoTRP channels, says David McKemy, a
researcher who studies the channels at the University of Southern
California in Los Angeles. The next challenge, he notes, may be to
uncover why the burn of garlic's allicin differs from that of other
thermoTRP stimulators, such as those in hot peppers, cinnamon, or
mustard.

Patapoutian notes that people have quite an unusual relationship to
flavor chemicals such as allicin. While people crave foods containing
thermoTRP-activating chemicals, most other animals tend to avoid them.
Observes Patapoutian: "It's an interesting issue of how humans have
come to like this [sensation]."