Food additive: Monosodium glutamate

MSG, which is the sodium salt of L‐glutamic acid (or L‐glutamate – dissociated form), is the most well‐known food additive used in foods.

Monosodium glutamate is used in the food industry as a flavor enhancer with an umami taste that intensifies the meaty, savory flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups.

It produces a flavor that cannot be provided by other foods. It elicits a taste described in Japanese as umami, which is translated to "savory". ‘Umami’ is used by the Japanese to describe the taste of monosodium glutamate as well as the meaty taste of certain fish and broth.

Umami is considered as one of the five main tastes which enhancing food palatability. monosodium glutamate consumption has increased throughout the world in recent years as flavoring in cooking.

It is suggested that food palatability increases with appropriate concentrations of monosodium glutamate. The basic sensory function of monosodium glutamate is attributed to its ability to enhance the presence of other taste-active compounds.

What is glutamate? Glutamate is an amino acid that is naturally abundant in both plant and animal proteins. Protein-rich foods contain sizeable amounts of glutamate as part of the protein. In addition, many foods also contain small amounts of “free” glutamate, usually in the form of sodium glutamate.
Food additive: Monosodium glutamate

The functions of flavor enhancer

Flavorings ether imparts a particular flavor to food or modifies flavors already present. Flavor enhancers, on the other hand, intensify flavors already present especially when the desirable flavors are relatively weak.

Flavor enhancers intensify mostly attributes of mouth feel such as dryness and astringency. Flavor enhancers are chemical compounds or materials that are used in very minutes quantities. At the levels of parts per thousand, in which they are usually used they do not add any flavor of their own to the food.

First used in fish and meat dishes they a now intensify desired flavors and mask unwanted ones in beverages, processed fruit and vegetables and bakes goods like breads and cakes.

Monosodium glutamate is one of the best known and is widely used flavor enhancers. Disodium guanylate and disodium inosinate are also common.

Most people are familiar with the use of table salt to enhance the flavor of a wide variety of foods. Salt can be an effective enhancer even at levels far below the threshold for salty taste and is widely used in processed foods such as canned vegetables and soups.
The functions of flavor enhancer

Chinese restaurant syndrome

Because symptoms are reported to occur shortly after sensitive individuals eat Chinese food, sensitive to MSG has been dubbed the ‘Chinese restaurant syndrome’.

Monosodium glutamate is the sodium salt of the amino acid, glutamic acid. It is commercially synthesized by taking protein, typically derived from wheat or soy, through and acid wash to unravel the amino acids.

The neutralizing agent sodium hydroxide is then added to form the sodium salt of each amino acid, celled hydrolyzed vegetable protein which constitutes of MSG 10% to 30% of the mixture.

Symptoms associated with MSG sensitive include dizziness, sweating, flushing, a rapid heartbeat and a ringing sound in the ears. It appears within 20 min and last up to 2 hours.

In 1968, Dr Robert Kwok wrote a letter to the New England Journal of Medicine describing some mild by uncomfortable symptoms after dining at certain Chinese restaurants.

People who experienced headaches and general feelings of ill health after eating Chinese food suddenly realized that they were not alone.

Chinese restaurant syndrome, also called monosodium glutamate symptoms complex and it is commonly believed that monosodium glutamate is the cause.

More serious symptoms attributed to the syndrome have included swelling of the throat, chest pain, heart palpitations, and shortness of breath.
Chinese restaurant syndrome

Monosodium Glutamate (MSG)

Monosodium Glutamate (MSG)
Glutamic acid was isolated by Ritthausen.

In 1098 Ikeda found that MSG is the beneficial active component of the algae Lamniria japonica, used for a long time in Japan as a flavor improver of soup and similarly prepared soup.

The taste of MSG cannot be explained by a combination of sweet, salty, sour and bitter tastes.

It is, as the fifth quality, of an elementary nature. This assumption, which was made as early as 1908 by a Japanese researcher to explain the special taste called umami, was recently confirmed by the identification of a taste receptor for MSG.

Indeed MSG is one of the most important taste-bearing substances in meat and ripened for longer periods of time.

Reports by Japanese researchers that glutamyl peptides, e.g., Glu-Glu, also taste like MSG have not been confirmed.

The taste of MSG is intensified by certain nucleotides. Glutamate promotes sensory perception particularly of meat like aroma notes, and is frequently used as an additive in frozen, dehydrated or canned fish and meat products.

MSG is added in the concentration range of 0.2 – 0.8%.

The intake of larger amount of MSG by some hypersensitivity persons can trigger a “Chinese restaurant syndrome”, which is characterized by temporary disorders such as drowsiness, headache, and stomach ache and stiffening of joints. These disappear after a short time.
Monosodium Glutamate (MSG)

Flavor Enhancers

Flavor Enhancers
Flavorings either a particular flavor to foods or modify flavors already present. Flavor enhancers intensify flavors already present, especially when the desirable flavors are relatively weak. Monosodium glutamate (MSG) is one of the best known and most widely used flavor enhancers. This compound occurs naturally in many foods and in certain seaweed that was used for centuries as a flavor enhancer for soups and other foods.

It is only within the last hundred years that the reason for the effectiveness of the seaweed was discovered to be MSG. The way in which MSG enhances flavor is not yet fully understood. While it is effective at relatively low levels (part per thousands), there are other compounds called flavor potentiators that also enhance flavors but are extremely powerful, effective in parts per million and even per billion. These compounds have been identified as nucleotides, and their effect is attributed to their synergies properties (properties that intensify that effect of natural flavor components).
Flavor Enhancers