What is monosodium glutamate made from?

Monosodium glutamate (MSG) is a common food additive used to enhance flavor. It has been used in cooking for over 100 years. MSG is the sodium salt of glutamic acid, which is an amino acid that occurs naturally in many foods. Understanding what MSG is made from can help explain why it is so widely used as a flavor enhancer.

Glutamic Acid

Glutamic acid is a non-essential amino acid that is found abundantly in nature. It is one of the most common amino acids present in foods. Glutamic acid is found in all protein-containing foods such as meats, dairy products, seafood, nuts, seeds, soy products, and wheat.

Some foods that naturally contain high levels of glutamic acid include:

  • Tomatoes
  • Cheese
  • Mushrooms
  • Peas
  • Grapes
  • Beef
  • Chicken
  • Fish
  • Eggs
  • Corn
  • Beets
  • Spinach
  • Broccoli
  • Carrots
  • Onions
  • Potatoes
  • Pumpkin
  • Zucchini
  • Yogurt
  • Soy sauce

The glutamic acid in these foods contributes to their savory, umami taste. Umami is one of the five basic tastes, along with sweet, salty, sour, and bitter. It is often described as a pleasant, brothy, or meaty taste.

Production of MSG

Although glutamic acid occurs naturally, most MSG is produced through bacterial fermentation. During the fermentation process, bacteria are fed carbohydrates from sources like sugar beets, sugar cane, or molasses. The bacteria break down these carbohydrates and convert them to glutamic acid through their metabolic processes.

After fermentation, the glutamic acid is separated from the fermentation broth. Sodium is then added to the glutamic acid to produce monosodium glutamate in crystal or powdered form.

Fermentation Process

Specifically, the production process involves:

  1. Bacteria such as Corynebacterium glutamicum are fed carbohydrate sources along with nutrients to help them grow.
  2. The bacteria metabolize the carbohydrates, producing glutamic acid as a byproduct of their growth.
  3. The fermentation broth contains glutamic acid as well as other amino acids and byproducts.
  4. The broth goes through various separation and purification steps to isolate the glutamic acid.
  5. The purified glutamic acid is then neutralized with caustic soda to increase the pH.
  6. Sodium chloride (table salt) is added which converts the glutamic acid to monosodium glutamate.
  7. Impurities are removed through crystallization and centrifugation.
  8. The final MSG crystals are dried and milled to produce the finished product.

The entire manufacturing process is tightly controlled to produce a consistent, high-purity product.

Raw Materials

The primary raw materials used to produce MSG through bacterial fermentation include:

  • Carbohydrate sources – Provide nutrients for the bacteria to grow. Common sources are molasses, sugar beets, and sugar cane.
  • Ammonium salts – Act as a nitrogen source for bacteria to synthesize amino acids.
  • Minerals and growth factors – Help optimize bacterial growth. Adding minerals like iron and zinc improves glutamic acid yields.
  • Water – Provides the liquid medium for bacterial growth.

These inexpensive and widely available agricultural products allow MSG to be made through an efficient fermentation process.

Chemical Properties

Glutamic acid, the basis for MSG, has certain chemical properties that influence how MSG works as a flavor enhancer:

  • It contains both an amino group (-NH2) and carboxyl group (-COOH) which makes it an amino acid.
  • The additional carboxyl group gives glutamate a negative charge at neutral pH.
  • This makes MSG soluble and stable in water-based foods.
  • The negative charge interacts with taste receptors on the tongue, part of what produces the umami taste.
  • MSG does not have its own distinct taste. It enhances existing savory flavors in food.

When glutamic acid is converted to monosodium glutamate, the sodium salt formation stabilizes the negative charge. This allows the MSG crystals to be isolated and used as a flavor enhancer.

History of MSG

MSG was first identified as a unique taste by Japanese scientist Kikunae Ikeda in 1908. He found glutamic acid in seaweed broth had a distinct savory taste different from sweet, salty, sour, and bitter. Professor Ikeda determined that this new taste, which he called umami, came from the glutamic acid in seaweed.

Initially, MSG was extracted from seaweed and other products containing glutamic acid. But producing MSG from seaweed was expensive and not efficient for large-scale production. The fermentation process used today was developed in the late 1950s by the Ajinomoto company. It allowed inexpensive, industrial-scale production of MSG from basic agricultural raw materials.

Today most MSG is made through bacterial fermentation rather than extraction from plant or animal sources. MSG produced by fermentation is also vegetarian and kosher certified since it does not use any animal products.

Reasons MSG is Widely Used

MSG became popular because it improves the flavor of foods without contributing significant calories or sodium on its own. Some reasons MSG is so widely used as a flavor enhancer include:

  • Naturally occurring – MSG contains glutamate, an amino acid found in many foods, so it can be considered a natural flavor.
  • No own taste – MSG enhances other flavors instead of adding its own distinct taste.
  • Umami flavor – Provides the savory, brothy, meaty umami taste which complements saltiness and sweetness.
  • No calories – Does not contribute any calories or macronutrients to foods.
  • Little sodium – Only 12% sodium by weight, so small amounts improve flavor without added sodium.
  • Stable – MSG crystals are stable so flavor enhancement remains even with cooking or over shelf life.
  • Versatile – Can be added to nearly any savory food or dish, either during preparation or before serving.

The unique properties of MSG make it an effective, versatile, and economical flavor enhancer for the food industry.

Sources of MSG in Food

In addition to direct use as a flavoring, MSG and glutamate are found in a wide variety of common processed foods. MSG can be used or found in:

  • Bouillon cubes, stocks and broths
  • Seasoning blends
  • Flavored chips and snacks
  • Canned soups
  • Frozen dinners
  • Cured meats like bacon or deli meats
  • Salad dressings and condiments
  • Restaurant foods
  • Sauces and gravies
  • Seasoned rice dishes
  • Flavored noodles packets

Food manufacturers are not required to disclose MSG as an ingredient. They may list added MSG under its official name “monosodium glutamate”, or use broader terms like “natural flavors” or “hydrolyzed vegetable protein”. Looking for these cues on ingredient lists can help identify potential sources of MSG.

Is MSG Safe to Eat?

MSG has been the subject of health concerns for decades, with some people claiming adverse effects like headaches or flushing after consuming it. However, most health authorities and scientific research consider MSG safe for consumption:

  • The FDA classifies MSG as Generally Recognized As Safe (GRAS).
  • European Food Safety Authority confirms MSG is safe for the general public.
  • Extensive research has found no definitive evidence of reactions to MSG in blinded, placebo-controlled studies.
  • Any responses are likely psychological in nature rather than physiological.
  • A small subset of people may have temporary reactions to large doses on an empty stomach.
  • Consuming moderate amounts with food is not harmful for most people.

While a small number of individuals may have a sensitivity to large MSG doses, it remains safe for the majority of the population. Any adverse effects only seem to occur when extremely high levels of MSG are consumed without food.

Uses in Cooking and Food Preparation

MSG is valued in commercial food preparation because it effectively improves flavor. It brings out the best tastes in various ingredients and dishes. MSG also has practical advantages for cooking at home or in restaurants:

  • Boosts flavor – A small amount of MSG can intensify and balance the flavor of meats, vegetables, soups, sauces, and more without overpowering.
  • Reduces sodium – MSG provides savory taste with much less sodium than table salt, so it can reduce total sodium.
  • Tenderizes meat – Adding MSG to meats helps break down muscle protein so it becomes more tender.
  • Accents sweetness – MSG balances and accentuates the sweetness in foods and desserts.
  • Easy to use – MSG dissolves readily in liquids for marinades or can be sprinkled as seasoning.
  • Heat stable – Unlike many seasonings, MSG retains its flavor enhancement even after prolonged cooking.

When used properly, MSG is an invaluable tool for making food taste great without unwanted sodium or calories. It’s especially useful for low-sodium diets where flavor still needs to be preserved.

Tips for Using MSG

To take advantage of MSG’s benefits as a flavor enhancer, here are some tips for use:

  • Start with a small amount like 1/4 tsp per pound of meat or 4 servings of a dish.
  • Mix MSG thoroughly into liquids for best distribution.
  • Add MSG near the end of cooking so the flavor remains.
  • Combine with salt substitutes containing potassium or magnesium.
  • Sprinkle on protein dishes, sauces, soups, dressings, ground meat.
  • Use in marinades along with salt, spices, and acids.
  • MSG blends nicely with garlic, onion, soy sauce, wine.

MSG is much more potent by weight than salt, so small quantities are usually sufficient. People’s sensitivity to taste varies, so use trial and error to find the right MSG amount.

Comparison to Salt

Table salt (sodium chloride) is often contrasted with MSG since both are commonly used as flavor enhancers:

Property Salt (NaCl) MSG
Taste Salty Umami, savory
Composition 40% sodium 12% sodium
Degree of flavor Mild enhancement Intense enhancement
Amount needed Relatively large Very small
Calories None None

This comparison shows that MSG provides substantial flavoring power with reduced sodium compared to regular salt. Switching even a portion of salt to MSG when cooking can cut down on total sodium intake.

Common Myths and Misconceptions

Despite MSG’s long history of use and food safety affirmations, some myths and misconceptions still persist:

Myth: MSG has major adverse health effects

Multiple rigorous studies have failed to definitively link MSG consumption with systematic health effects. Any symptoms in a small subset of the population are likely transitory.

Myth: MSG causes Chinese restaurant syndrome

“Chinese restaurant syndrome” with symptoms like headaches or numbness is anecdotal and not verified scientifically under controlled conditions.

Myth: MSG is artificial or synthetic

MSG contains glutamate like many foods. Modern production via bacterial fermentation is not less “natural” than extraction from other sources.

Myth: MSG is high in sodium

MSG only contains 12% sodium by weight, far less than the 40% in sodium chloride salt.

Myth: MSG is an allergen for many people

True MSG allergies are extremely rare. Some short-term sensitivities may occur in certain individuals.

Myth: MSG is highly toxic

Animal studies have found MSG is no more toxic than typical table salt when consumed in reasonable amounts.

These common misunderstandings about MSG lack strong clinical evidence. MSG has an extensive track record of safe use for most people.

Finding MSG-Free Foods

People wishing to avoid MSG do have options to find MSG-free foods:

  • Read labels carefully – Look for MSG listed under alternate names like “glutamate” or “hydrolyzed protein”.
  • Choose whole, unprocessed foods – MSG is mostly used in heavily processed, commercial products.
  • Cook from scratch – Making meals at home lets you control flavoring ingredients.
  • Look for MSG-free labels – Some products carry explicit “No MSG” labels.
  • Patronize Asian restaurants claiming no MSG – Many continue to avoid MSG due to the Chinese restaurant syndrome misconception.
  • Use arrowroot, nutritional yeast, seaweed – These umami-rich ingredients provide flavor without MSG.

With careful label reading and whole food choices, people wishing to avoid MSG can largely do so with minimal hardship.


MSG is made from the sodium salt of glutamic acid, an amino acid that occurs widely in nature and gives food its savory umami taste. Today most MSG is efficiently produced by bacterial fermentation of carbohydrates. MSG provides substantial flavor enhancement with minimal calories and sodium. It has an extensive track record of safe use despite some lingering misconceptions. People wanting to avoid MSG can do so by preparing whole foods or choosing products labeled MSG-free.

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