"James" > wrote in message
...
>I know it's supposed to be bad for you but it makes my fried eggs
> taste soooooooo good.

Interestingly the glutamate flavor is now regarded as the 5th taste and it
is believer we have glutamate (Umami) receptors in our tongues.

Sweet, Sour, Salt, Bitter, & Umami

Dimitri

See Below

From Wikipedia, the free encyclopedia

For the record label, see Umami Records.

Umami (??, Umami?) is one of the five basic tastes sensed by specialized
receptor cells present on the human tongue.[1] The same taste is also known
as xianwèi (traditional Chinese: ??; simplified Chinese: ??) in Chinese
cooking.
Umami is a Japanese word meaning savory, a "deliciousness" factor deriving
specifically from detection of the natural amino acid, glutamic acid, or
glutamates common in meats, cheese, broth, stock, and other protein-heavy
foods. The action of umami receptors explains why foods treated with
monosodium glutamate (MSG) often taste "heartier".
Glutamate has a long history in cooking: it appears in Asian foods such as
soy sauce and fish sauce, and in Italian food in parmesan cheese and
anchovies. It also is directly available in monosodium glutamate (MSG).[2]
Inasmuch as it describes the flavor common to savory products such as meat,
cheese, and mushrooms, umami is similar to Brillat-Savarin's concept of
osmazome, an early attempt to describe the main flavoring component of meat
as extracted in the process of making stock.


[edit] Chemical properties
Main article: Monosodium glutamate
Umami was first identified as a basic taste in 1908 by Kikunae Ikeda of the
Tokyo Imperial University while researching the strong flavor in seaweed
broth.[3][4] Ikeda isolated monosodium glutamate as the chemical responsible
and, with the help of the Ajinomoto company, began commercial distribution
of MSG products.

[edit] Taste receptors
Acknowledged subjectively as a special taste by Eastern civilizations for
generations, umami has been described in biochemical studies identifying the
actual taste receptor responsible for the sense of umami, a modified form of
mGluR4[5] named "taste-mGluR4".
Umami tastes are initiated by these specialized receptors, with subsequent
steps involving secretion of neurotransmitters, including adenosine
triphosphate (ATP) and serotonin.[6] Other evidence indicate guanosine
derivatives may interact with and boost the initial umami signal.[7]
Cells responding to umami taste stimuli do not possess typical synapses but
instead secrete the neurotransmitter ATP in a mechanism exciting sensory
fibers that convey taste signals to the brain. These taste receptors are
located everywhere on the tongue.[citation needed]
In monkey studies, most umami signals from taste buds excite neurons in the
orbitofrontal cortex of the brain, showing spatially-specific
characteristics:[8]
There is a cortical map representation for the taste of glutamate separate
from that of other taste stimuli like sweet (glucose), salt (sodium
chloride), bitter (quinine), and sour (hydrochloric acid)

Single neurons having vigorous responses to sodium glutamate also respond to
glutamic acid
Some neurons display a mechanism of satiety, indicating a process by which
taste receptors in the mouth may interact with cortical neurons to curtail
eating

Umami flavor is strongest when combined with aromas (e.g., monosodium
glutamate and garlic), a result leading to speculation that glutamate may
stimulate umami effects by acting simultaneously with the aromas, texture,
and appearance of food.