The Science of Savory: What is Natural MSG?
Monosodium glutamate (MSG) is the sodium salt of glutamic acid, an amino acid abundant in nature. While commercially produced MSG is a familiar food additive, a version of MSG, known as 'free glutamate,' occurs naturally in many foods. The release of this free glutamate is what provides the fifth basic taste, umami, which is characterized by a deep, savory flavor. The key to finding high levels of natural MSG isn't just a specific ingredient, but often the process it undergoes. Ripening, drying, fermenting, and aging all break down proteins and release more free glutamate, amplifying the umami flavor.
Top Foods Packed with Natural MSG
Several foods stand out as being exceptionally rich in free glutamate due to natural processing. These are the ingredients chefs and home cooks use to add a powerful savory punch to dishes.
Kombu (Dried Kelp)
Kombu, a type of edible dried kelp, was the very food from which umami was first identified by Japanese chemist Kikunae Ikeda in 1908. It remains one of the most concentrated natural sources of glutamate. The glutamate content can range from 230 to a staggering 3,380 mg per 100g, depending on the variety and preparation. It is the foundation for dashi, a cornerstone broth in Japanese cuisine.
Parmesan Cheese
This aged hard cheese is a powerhouse of umami. As Parmesan matures, its proteins break down into free glutamates, which is why older Parmesan has a richer, more complex flavor. With a glutamate content that can reach 1,200 to 1,680 mg per 100g, it is consistently cited as one of the highest sources of natural glutamate. This is why adding a Parmesan rind to soups or a sprinkle of grated Parmesan to pasta is a classic way to enhance savory flavor.
Fermented Soy Products
Fermentation is a well-known method for boosting umami, and soy products are a prime example. Soy sauce, miso paste, and other fermented soy ingredients all contain high levels of free glutamate. Soy sauce, for instance, typically contains between 400 and 1,700 mg of glutamate per 100g, while miso paste can range from 200 to 700 mg. This fermentation process unlocks the amino acids stored in the soybeans, releasing the savory glutamate.
Dried Shiitake Mushrooms
While fresh mushrooms contain moderate glutamate levels, the drying process concentrates their umami potential significantly. Dried shiitake mushrooms can contain up to 1,060 mg of glutamate per 100g. Soaking these mushrooms and using both the rehydrated mushrooms and the flavorful liquid is a fantastic way to impart a rich, meaty depth to vegetarian dishes, broths, and sauces.
Cured and Aged Meats
Similar to aged cheese, the curing process in meats breaks down proteins and releases free glutamate. Cured ham is a great example, with its glutamate levels being significantly higher than that of fresh pork. The curing process concentrates the savory flavor, which is a key reason for the popularity of cured meats like bacon, prosciutto, and salami.
Ripe Tomatoes
As tomatoes ripen, their glutamate levels increase dramatically. A ripe tomato can contain up to 250 mg of glutamate per 100g, a figure that becomes even more concentrated when the tomatoes are dried or made into paste. This is why a simple tomato sauce, cooked low and slow, develops such a deep and satisfying umami flavor.
Comparison of Natural Glutamate Sources
To put these figures into perspective, here is a comparison of the free glutamate content of several umami-rich foods. Note that values can vary based on ripeness, age, and preparation method.
| Food (per 100g) | Free Glutamate (mg) | Processing Method |
|---|---|---|
| Kombu (dried kelp) | 230–3380 | Drying |
| Parmesan Cheese | 1200–1680 | Aging |
| Dried Shiitake Mushrooms | ~1060 | Drying |
| Soy Sauce | 400–1700 | Fermentation |
| Fish Sauce | 727–1383 | Fermentation |
| Cured Ham | ~340 | Curing |
| Ripe Tomatoes | 140–250 | Ripening/Concentrating |
Natural vs. Added MSG
The human body cannot distinguish between the glutamate that naturally occurs in foods and the glutamate added as a flavor enhancer. Both are metabolized in the exact same way. The primary distinction is the source and concentration. Naturally occurring glutamate is part of a complex matrix of proteins, while added MSG (monosodium glutamate) is a pure, isolated form. Despite decades of controversy based on anecdotal evidence, regulatory bodies like the FDA classify added MSG as 'generally recognized as safe' (GRAS), and scientific studies have failed to consistently trigger reactions in sensitive individuals at typical consumption levels. However, individuals concerned about or sensitive to free glutamate should be mindful of the high amounts present in certain natural foods and concentrated products. For more information on glutamate and the umami taste, you can visit the Umami Information Center.
Conclusion: Sourcing Savory Flavor
Ultimately, the question of what has the most natural MSG points to a wide range of ingredients where natural aging, ripening, and fermentation have concentrated the savory power of free glutamate. While kombu seaweed and aged cheeses like Parmesan are undisputed leaders in concentration, a variety of other foods like dried mushrooms, fermented sauces, and cured meats offer potent and delicious ways to boost umami. Understanding these natural sources not only clarifies misconceptions about MSG but also provides a roadmap for creating richer, more flavorful meals using whole foods.
