MSG Allergy and Related Implications
There are many different foods containing MSG that are available for purchase. Monosodium glutamate msg is a common ingredient in many items and is used as a ‘flavor enhancer’. There is a lot of controversy surrounding MSG. Because glutamate is used in nerve conduction and signal transmission in the body, some people claim to have symptoms when consuming it. This causes the MSG allergy of headache, nausea, GI distress and other symptoms from increased synaptic activity. The group of chemicals, the glutamates, all have a similar structure and function. They can be formed in several different ways, including fermentation and hydrolysis (bond breaking) of proteins.
Glutamic acid can exist in many forms. It can be consumed as an ion, which is a charged particle, or a salt, which is neutral. MSG is a salt because of the single sodium. All of the different types of glutamic acids, their ions and salts, are called glutamates. They are used because of their flavor-enhancing properties. These compounds provide an umami (savory) taste to food that is widely desired. Glutamic acid is a natural part of many fermented or aged foods because the glutamate can be formed over time. These include soy sauce, fermented bean paste, as well as cheese. It is also a component of any hydrolyzed protein, such as yeast extract or others.
Most of the MSG used in cooking is produced by fermentation of some sort of sugar product. The most commonly used are starches, sugar beets, sugar cane, or molasses. There were about 1.5 million tons sold in 2001, which represents 4% annual growth. MSG is used commercially and has been traditionally associated with chinese food. MSG is now used by most fast food chains and in many foods. Most of these are processed foods. But it can occur naturally as discussed above. That is why they have been some arguments about the labeling of food as having ‘no MSG’ since it is not added specifically. Some of these foods may have it as part of the fermentation. So the no MSG label is not really true since it occurs naturally.
The most common foods that contain MSG include some of the following items. Pre-prepared stocks such as stock cubes or bouillon cubes and certain condiments such as barbecue sauces and salad dressings. Canned, frozen, or dried prepared food as well as common snack foods can also contain it. For example, flavored jerky, flavored potato chips and flavored tortilla chips can have MSG. Seasoning mixtures are another common source of the additive. It had been found that only the L-glutamate enantiomer (mirror image molecule) has flavor enhancing characteristics. Some of the fermented products such as soy sauce, steak sauce, and Worcestershire sauce tend to have high levels of glutamate. People who have an msg allergy are going to be sensitive to all of these different foods and should avoid them if possible. But this can be difficult to do in practice since there are many foods containing msg in stores and restaurants.