Although glutamate is naturally occurring in many foods, it is frequently added as a flavor enhancer. Foods containing large amounts of free glutamate, such as tomatoes, mushrooms and cheese have long been used to obtain savory flavors in dishes. In fact, we consume about 20–40 times more naturally occurring glutamate in the food that we eat than we do MSG.
Glutamate is often used to enhance the natural flavors of meats, poultry, seafood, snacks, soups and stews. When glutamate is added to foods, it provides a flavor profile similar to naturally occurring free glutamate.
The most popular glutamate-based flavor enhancer is monosodium glutamate (MSG). Monoammonium glutamate, monopotasium glutamate, and ribonucleotides compounds including disodium 50-monoinosinate (IMP) and disodium 50-monoguanylate (GMP) are also used as additives in foods.
Glutamate is present in foods not only as flavor enhancer, but also as a byproduct of hydrolyzed vegetable proteins, which are widely used as seasonings and flavoring agents in canned foods, dry mixes, sauces, and other manufactured products. Hydrolyzed vegetable proteins are often used as a substitute for MSG, because, although safe, consumers are wary of the food additive and its safety profile.
Glutamate is frequently added to processed foods and is shaken onto foods during preparation, particularly in Asian cuisine. The glutamate concentration in convenience foods adds up to 0.1–0.8 percent of weight, which is similar to the concentration of natural free glutamate in tomatoes or parmesan cheese.