(NaturalNews) "Yeast extract" is an innocuous-sounding ingredient that forms the base of several popular condiments worldwide, including Marmite, Vegemite, Promite, Oxo, Cenovis and Vitam-R. Yet, chemically, yeast extract is highly similar to MSG (monosodium glutamate).
Glutamic acid, the chemical responsible for the "umami" or savory flavor of foods, is found in high levels inside yeast cells, which is why so many naturally umami-rich foods are products of fermentation. MSG is an artificially concentrated glutamate salt that produces negative health effects.
Yeast extract is made by gathering the yeast produced during fermentation of beer and other products, then either autolyzing or hydrolyzing the cells.
Autolyzed yeast extract is made by adding salt to yeast, which causes the cell to dry up and self-destruct. Hydrolyzed yeast extract is produced by adding chemical enzymes that kill the yeast cells outright.
Both processes cause the cell walls of yeast to rupture. Refining processes are then used to remove these cell walls, leaving only a concentrated paste high in glutamic acid. This may be left in the form of a paste or dried and used as a powdered food additive.
At this point, there is little difference between the final product and MSG.