Why is glutamic acid added to food? Unpacking the science of savory flavor

October 14, 2025 •

3 min read

The fifth basic taste, umami, was identified over a century ago by Japanese professor Kikunae Ikeda, who discovered that the amino acid glutamic acid was responsible for this savory sensation. Today, manufactured glutamic acid is widely added to food in the form of monosodium glutamate (MSG), primarily to enhance and intensify the flavors of various dishes.

Quick Summary

Glutamic acid, most often as the food additive MSG, is added to foods to create the savory umami flavor and improve palatability. This process intensifies the inherent flavors of ingredients, allowing for reduced sodium content without sacrificing taste. The body metabolizes naturally occurring glutamate and added MSG identically, and major health bodies consider it safe for consumption.

Key Points

Flavor Enhancement: Glutamic acid, particularly as MSG, is added to food to create and enhance the savory umami taste, improving palatability and overall flavor.
Natural vs. Added: The body cannot differentiate between naturally occurring glutamate found in foods like cheese and tomatoes, and commercially produced MSG; both are metabolized identically.
Safety Approved: The FDA and international bodies have designated MSG as 'Generally Recognized As Safe' (GRAS) based on extensive scientific evidence, debunking the historical 'Chinese Restaurant Syndrome' claims.
Sodium Reduction: Adding glutamate can reduce the overall sodium content of food while maintaining a satisfying, savory flavor profile, aiding in dietary sodium management.
Widespread Use: Added glutamates are present in many processed foods, soups, and seasonings, and can be identified by names like 'monosodium glutamate', 'yeast extract', or 'hydrolyzed protein'.
Natural Sources: Fermented products (soy sauce, aged cheese) and ripe vegetables (tomatoes) are rich natural sources of free glutamic acid and umami flavor.

Glutamic Acid and the Power of Umami

Glutamic acid is an amino acid found naturally in living cells and protein-rich foods. While bound in protein, it is tasteless, but in its “free” form, it provides the savory taste known as umami. This was first isolated from kelp in 1908 by Japanese chemist Kikunae Ikeda. This discovery led to the creation of monosodium glutamate (MSG), a sodium salt of glutamic acid, to add umami flavor to foods.

The primary reason glutamic acid (or MSG) is added to food is for its flavor-enhancing properties. It intensifies taste profiles and creates a more satisfying experience by stimulating specific taste receptors.

The Role of Umami in Food Production

Food manufacturers use glutamic acid in the form of MSG primarily to enhance savory flavors and improve palatability. It helps boost the natural tastes of ingredients and makes food more enjoyable.

The Difference Between Naturally Occurring and Added Glutamate

The body processes glutamate from all sources in the same way, whether from fermented foods or MSG. The difference lies in how it's presented to taste buds.

Comparison Table: Natural Glutamate vs. Added MSG


Aspect	Natural Glutamate	Added MSG
Source	Found in foods like tomatoes, cheese, mushrooms, and meat.	Produced commercially through fermentation of carbohydrate sources.
Form	Exists as protein-bound (tasteless) and free (umami-flavored); free glutamate increases with ripening, fermentation, or cooking.	Added as a purified powder that dissolves and releases free glutamate ions.
Flavor Contribution	Contributes to the complex savory taste of aged and fermented foods.	A potent umami enhancer that boosts overall savory perception.
Labeling	May be listed as the food itself (e.g., "yeast extract"), but doesn't require a separate MSG label unless added directly.	Must be listed on the ingredient panel as "monosodium glutamate".

Glutamate: A Safe and Studied Food Additive

Despite past controversies, major health authorities have confirmed MSG's safety. The FDA designated MSG as “Generally Recognized As Safe” (GRAS) in 1958, and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) also places it in the safest category.

Studies have not found consistent evidence to support a link between MSG and symptoms reported in the past, often referred to as "Chinese Restaurant Syndrome," particularly at typical consumption levels. The FDA concluded that adverse event reports were not consistently confirmed to be caused by MSG.

Health and Nutritional Considerations

Glutamic acid is an important non-essential amino acid. The gut rapidly metabolizes dietary glutamate, using it as an energy source for intestinal cells, so very little enters systemic circulation.

Glutamate-based additives can be beneficial for managing sodium intake. Since glutamate enhances salty tastes, less table salt is needed to achieve a satisfying savory flavor, which can help create healthier food products.

Conclusion

Glutamic acid is added to food to utilize its savory umami flavor, either as MSG or through glutamate-rich ingredients. This enhances taste, improves palatability, aids in low-sodium products, and intensifies existing flavors. Decades of scientific research support the safety of glutamic acid and MSG for the general population. Glutamate from natural sources and added MSG is metabolized similarly, making it a safe and effective culinary tool. For more information on MSG, visit the {Link: FDA's Q&A page https://www.fda.gov/food/food-additives-petitions/questions-and-answers-monosodium-glutamate-msg}.

What to Look For on Food Labels

In the U.S., "monosodium glutamate" must be listed if added directly. Ingredients naturally high in free glutamates or those where glutamate is released during processing include Hydrolyzed Vegetable Protein (HVP), Yeast Extract, Soy Extracts, and Protein Isolate. Processed glutamate may also be included under "Natural Flavors" under certain regulations.

Frequently Asked Questions

Glutamic acid is an amino acid found in nature, while monosodium glutamate (MSG) is the sodium salt of glutamic acid. In food products, MSG dissociates into free glutamate and sodium, and this free glutamate provides the umami taste. Free glutamate from natural sources and from MSG are chemically identical.

Extensive scientific research confirms that added glutamic acid, as MSG, is safe for the general population. The FDA designated MSG as 'Generally Recognized As Safe' (GRAS) decades ago, a finding supported by international bodies.

Umami is the fifth basic taste, described as savory. Glutamic acid and its salts stimulate specific taste receptors, signaling a protein-rich food source.

While some report sensitivity, clinical studies haven't consistently triggered symptoms in those who believe they are sensitive. Reported effects are typically mild and transient, often linked to consuming large amounts of MSG without food.

High doses can have effects, but it's unlikely to consume enough MSG in a typical meal to cause issues. The body regulates intake, as very high concentrations become unpalatable. Studies on adverse effects often use large doses consumed alone.

In the U.S., "monosodium glutamate" must be listed if added directly. Ingredients naturally high in glutamate or that release it include yeast extract, hydrolyzed vegetable protein, and soy extracts.

Yes, using MSG can help reduce total sodium intake. By enhancing savory flavor, less table salt is needed for a satisfying taste, which is beneficial for health.