AJINOMOTO.
INTRODUCTION.
Ajinomoto is the brand name of MSG. Most commonly known as MSG, monosodium glutamate is the sodium salt of glutamic acid, which is an amino acid also found in mushrooms. MSG has no flavor of its own, but it does enhance the flavor of other foods. Originally,extracted from sea-weeds or wheat gluten, it was first discovered in the Orient,where it still remains a popular flavor enhancer.
HISTORY.
MSG , has been a ingredient in Japanese cooking for a very long time,but was not actually not produced as a flavoring material until 1909. In 1908, Kikuunae Ikeda, Japanese scientist, was intent on isolating a basic taste substancethat was neither sweet, salt sour nor bitter. While, studying a particular kind of kelp, a sea-weed traditionally used to make soup, he isolated the glutamate ion and found it to have its own taste , which he described as “savory” and to alter the tastes of other foods in an appetizing way.
SYNTHESIS.
Moon sodium glutamate is manufactured biosynthetically.
In the 1950s, a bacterium was isolated that synthesis and excretes glutamic acid when fed an excess of ammonium ion (NH4)+; which supply the necessary nitrogen. Japanese use MSG to cover table salt, thereby preventing it from caking and expanding its contribution of flavor.
Today, most of the MSG,is produced by direct fermentation processes, which in the processes crystallizes the sodium salt of glutamic into white crystals.
OCCURANCE
MSG occurs naturally in wheat , meat , poultry, sea-weeds and other foods, and since the 1900s it has been manufactured by several methods, which is been already been discussed.
PRODUCTION.
The worlds supply, which was recently reported to be 150 million lb per year valued at about $80 million cores mainly from Japan. Production in the U.S. is less than 25% of the total amount produced. When one considers that mono-sodium glutamate usage is at a level of 1/10th the concentration of salt used in food, and that its use is restricted to protein foods, one begins to appreciates the impact of this oriental seasoning on American food habits. It is assumed that about 30 billion ib of protein foods are seasoned annually.
CHEMICAL STRUCTURE.
Glutamic acid is the most widely occurring amino acid present acid present in the nature.
Levo-glutamic acid is found in cereal, fish, poultry and meat proteins: Levo-monosodium glutamate, MSG ,is manufactured biosynthetically, and is widely used as a protein flavor aecentutor.
H
|
COOHCO2 CH2---C---COOH
|
NH2
LEVO—GLUTAMIC ACID.
H H
| |
COOHCH2CH2C---COONa.H2O
| |
NH2
LEVO—MONOSODIUM GLUTAMATE MONOHYDRATE.
The natural or glutamic acid,when neutralized carefully with sodium hydroxide to pH-7,enhances and accentutates proteins flavors in vegetables, grains, fish, poultry and meat. When the L—form is racemized by excessive heating it loses its flavor-amplifying activity. A synthetic DL mixture has only one-half the flavor- potentiating properties of the L- form. Since glutamate activity is based upon palate sensitization to protein flavors, it may be concluded that the taste receptors are attuned only to the L-form.Itis freely soluble in water while sparingly soluble in alcohol.
MSG---- AS A FLAVORING AGENT.
For centuries salt, sugar, spices and wood smoke have been added to supplement the natural flavors that occur in foods. These additives lend savory richness to certain dishes.
Atotal list totalling 1023 flavoring ingredients were compiled recently. MSG as a seasoning and flavor potentatior were developed in the Orient to make vegetable protein foods tolerable to meat eater.
MSG and the sodium salts of the 5 nucleotides are natural seasonings that act at the receptors surface of the taste buds. Food flavor is affected by nucleotide binding of metal ions that sensitizes tasting sites that are otherwise not active in enhancement of flavors. This effect on yhe taste buds is called the “glutamate effect”.
But, when an excess of MSGis added, a glutamate taste is superimposed on the natural flavor of the food. Usually, in yhe pork and poultry products a conc. Of 1 parts MSG per 1000 parts of foods by wt. Suffices. Beef requires 2 ½ parts of MSG per 1000 parts of beef products.
Bad flavors are intensified by the addition of MSG. For e.g. when stag meat is used in sausage at concentrations as low as 1% -2% addition of MSG brings out a strong urinary taste and odor, especially upon heating. In other words, MSG not only cannot improve a bad p[product, but makes it taste worse. In meat products made from old and tainted meats MSG is eliminated from there formulas, and peppery connections substituted that smell like pizza. These strongly flavored preparations anathesies the taste buds, and mask the spoiled taste of meat flavor.
Nucleotide seasonings derived from yeast or other microbiological sources are replacing parts of the MSG used for flavor potentiators. Disodium insonate and Disodium guanylate added to MSG at a concentration of 5 parts nucleotide per 100 parts MSG substantially reduces the proportion of seasoning required to potentitate proteins flavors. Yeast autolyzes with seasoned disodium inosinate and disodium guanylate is being used as substitute.
DISEASES.
Since MSG is derived from glutamic acid, the most abundant protein building block in nature, those who are allergic or sensitive to proteins may be sensitive to MSG. A “Chinese restaurant syndrome” is chartersied by
#) burning sensation of heart,
#)A feeling of pressure in the chest,
#) facial tightness or numbness,
#) bad headache.
They rarely last for more than an hour.This occurs predominantly because of the excessive usage of the salt. However, generally only those who are sensitive to wheat and other proteins are affected, and they represent only 0.1%of the population.
Principle food borne diseases, outbreaks and there causes are divided mainly into two major factors,
BACTERIAL ----64.3%.
CHEMICAL ----- 24.4%.
Out of these 24.4%the chemical diseases only 1.3% is because of MSG which accounts for only 7 persons in 100.
This data was according to the survey conducted by in the U.S. in the year 1980.
Moreover people those who are on a low sodium diet, especially suffering from Odema and sometimes with high - blood pressure should resist from taking MSG in there diet. Another reason is because glutamic acid is found in especially large concentrations in nervous transmission of the impluses, it has been suggested that a temporary dietary excess may disrupt partsof the nervous system.
CONCLUSION.
You either swear by it or curse it. Many professional Chinese chefs call ajinomoto “The master” because a handful of the composition allow them to serve just about anything and make it taste good. But, in recent years there has been a wide backlash aganist the use of the substance and many people doubt its value from a culinary angle and fear its side effects from the point of view of he health.
Many discriminating chefs and experienced cooks refuse to use MSG and in such culinary capitals as Hong- Kong there is a move in a number of leading Chinese restaurants to ban its use. Some of these establishments proudly boast that they do not use MSG; the results is that they attract hordes of knowledgeable gourmets who want to savor real tastes unstead of chemicals.Wether MSG really does have any kind of carcinogenic effect or its just a placebo one remains yet to be seen.
Sunday, March 25, 2007
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