"If you really love your Chinese or Sushi take-out, you might want to sit down for this.
Soybean meal and often corn starches are rapidly reduced to their component amino acids using a high-tech process known as “rapid hydrolysis” or “acid hydrolysis,” which involves heating defatted soy proteins with eighteen percent hydrochloric acid for 8 to 12 hours, then neutralizing the brew with sodium carbonate.
The result is a dark brown liquid — a chemical soy sauce.
When mixed with some genuine fermented soy sauce to improve its flavor and odor, it is called a “semi chemical” soy sauce. Sugars, caramel colorings and other flavorings are added before further refinement, pasteurization and bottling.
The rapid hydrolysis method uses the enzyme glutamase as a reactor. This creates large amounts of an unnatural form of glutamic acid that closely resembles that found in MSG. In contrast, production of genuine old-fashioned soy sauce uses the enzyme glutaminase to form naturally occurring glutamic acid..." read moreMSG Ingredient list http://www.truthinlabeling.org/hiddensources.html