Glutamate- fifth
of the basic tastes
In 1908 Japanese researcher Kikunae Ikeda of the Tokyo Imperial University
identified brown crystals left behind after the evaporation of a large amount
of kombu broth as glutamic acid. These crystals, when tasted, reproduced the
ineffable but undeniable flavor he detected in many foods, most especially in
seaweed. Professor Ikeda termed this flavor umami. He then patented a method of mass-producing a crystalline
salt of glutamic acid, monosodium glutamate.
Glutamic acid, being a constituent of protein, is present in every food
that contains protein, but it can only be tasted when it is present in an unbound form. Significant amounts of
free glutamic acid are present in a wide variety of foods, including cheese and
soy sauce, and is responsible for umami, one of the five basic tastes of the
human sense of taste. Glutamic acid (E620) is often used as a food additive and
flavor enhancer in the form of its salt, known as monosodium glutamate (MSG). MSG
has the HS code 29224220 and the E number E621.
Glutamate (the conjugate base of glutamic acid) is present in small amounts in every
cell in the body and is one of the chemical messengers present in the brain
responsible for transmitting information from one cell to another. Brain cells
make their own glutamate.
Normally Glutamate does not get from the blood into the brain unless
present in excessive amounts. Eat meal extremely glutamate
stimulates glutamate receptors in the hypothalamus and cardiac conduction system
and can cause sudden
cardiac death.
"Chinese restaurant syndrome" , which is a sudden fall in blood
pressure with subsequent fainting after ingestion of very spicy food, might be
caused by excessive amounts flavour enhancer monosodium glutamate (MSG). It is not a disease, but rather a certain type of food allergy (headache,
abdominal pain, cramps, facial flushing, feeling hot, increased heart rate).
Large amounts of glutamate include tomatoes (140 mg / 100 g), fungi (140 mg
/ 100 g), corn (130 mg / 100 g), cheese (120 mg / 100 g), such as blue cheese
or Parmesan cheese, cows milk, breast milk, ham, etc. Glutamate is released also
by preparing broth from the meat ( product of protein fission).
Human body contains about 2 kg of glutamate. Glutamate forms with other
amino acids proteins which form organs and tissues. Body produces 50 g free
glutamate per day which is required to the various life processes of
metabolism.
Human body can not distinguish between the glutamate that occurs naturally
in foods and monosodium glutamate used as an additive.
Higher amount of glutamate, whether naturally occurring or added, allows to
reduce the salt content in the food about 20 to 40%, without significant deterioration of
the mouthfeel of the food.
Glutamate in our brain can affect satiety. We eat more as our body needs.
Glutamate contains 12% of sodium. Our body works Sodium-potassium pump,
which helps us manage the fluids in the body. If the sodium excess, it leads to
water retention in the body, which can cause high blood pressure and other problems.
Humanity eats annually 1.5 million tons glutamate.
It has been reported, that the safe dose of Glutamate is 120mg/kg weight of
human being (outside the natural supply of raw food). LD50 for rats is 16.6g/kg
orally (for table salt it is 3g/kg). Glutamate is for rat less toxic than kitchen
salt.
Small amount of Glutamate should be harmless for an adult and should not
cause long-term failure. We eat approximately 10g of a bound form glutamate in
a daily doses. Glutamat in unbound form might cause a problem, it seems the
daily doses is very individual. Some people react to the food ingredient
monosodium glutamate and may experience problems in a very small quantities (1
g) ("Chinese restaurant syndrome").
Infants and children under 3 years should not be given MSG into their food.
They respond sensitively as they have many NMDA receptors (Glutamate receptor)
where Sodium glutamate can be bound. High intake of MSG can causes by them nerve cell death. The number of NMDA receptors decreases with age.
How to decrease
level of Glutamate in your body
Leucine (cheese, soybeans, beef, chicken, pork, nuts, seeds, fish, seafood, and beans), Isoleucine (lean meats, fish, liver, eggs, poultry, chickpeas, lentils, cashew nuts, almonds and soy proteins) and Lysine (lean beef, cheese, turkey, chicken, pork, soy, fish, shrimp, shellfish, nuts, seeds, eggs, beans, and lentils) are amino acids that reduce the absorption of glutamic acid.
Hidden sources of MSG
Names of ingredients that always
contain processed free glutamic acid: Glutamic acid (E 620), Glutamate (E 620), Monosodium glutamate (E 621), Monopotassium
glutamate (E 622), Calcium glutamate (E 623), Monoammonium glutamate (E 624), Magnesium
glutamate (E 625), Natrium glutamate, Anything “hydrolyzed”, Any “hydrolyzed
protein”, Calcium caseinate, Sodium
caseinate, Yeast extract, Torula yeast, Yeast food, Yeast nutrient, Autolyzed
yeast, Gelatin, Textured protein, Whey protein, Whey protein concentrate, Whey
protein isolate, Soy protein, Soy protein concentrate, Soy protein isolate, Anything
“protein”, Anything “protein fortified”, Soy sauce, Soy sauce extract, Anything
“enzyme modified”, Anything containing “enzymes”, Anything “fermented”, Anything
containing “protease”, Vetsin, Ajinomoto, Umami
Names of ingredients that often
contain or produce processed free glutamic acid during processing: Carrageenan (E 407), Bouillon and broth, Stock, Any “flavors” or
“flavoring”, Natural flavor, Maltodextrin, Oligodextrin, Citric acid, Citrate
(E 330), Anything “ultra-pasteurized”, Barley malt, Malted barely, Brewer’s
yeast, Pectin (E 440), Malt extract, Seasonings
The following are ingredients
suspected of containing or creating sufficient processed free glutamic acid to
serve as MSG-reaction triggers in highly sensitive people: Corn starch, Corn syrup, Modified food starch, Lipolyzed butter fat, Dextrose,
Rice syrup, Brown rice syrup, Milk powder, Reduced fat milk (skim; 1%; 2%), most
things “low fat” or “no fat”, anything “enriched”, anything “vitamin enriched”,
anything “pasteurized”, Annatto, Vinegar, Balsamic vinegar, certain amino acid
chelates (Citrate, aspartate, and glutamate are used as chelating agents with
mineral supplements).
„The dose makes the poison“ Paracelsus (late 1493 - 24/9/1541,
Swiss German philosopher, physician, botanist, astrologer, and general
occultist
Difference between L-and
D-Glutamic acid
Amino acids exist in two three dimensional forms, which are virtual mirror
images of each other. The two forms are referred to in the art by the direction
in which they rotate polarized light-levorotatory (L) and dextrorotatory (D), respectively
left and right. Fischer representations of the structural formulas for the two
enantiomers of glutamic acid are depicted below.
The L-enantiomer is the naturally occurring form of each amino acid found
in nature. The L-enantiomer of each amino acid that forms a part of a drug
agent is also the “active” enantiomer for medicinal purposes. A antifolates
which contain only the L-enantiomer of glutamic acid are much more active than
those which include the D-enantiomer in a racemic mixture of the two
enantiomers. The pure D-enantiomer is virtually inactive as a drug.
Warning: Health
information and the names of the drugs mentioned in the article are only for
orientation in the field of self-medication and does not replace communication
with your doctor. Before taking any medication, read the leaflet or ask your
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