Description
Magnesium carbonate is a basic hydrated magnesium carbonate
or a normal hydrated magnesium carbonate. It occurs as light,
white, friable masses, or as a bulky, white powder. It is odorless,
and is stable in air. It is practically insoluble in water, to which,
however, it imparts a slightly alkaline reaction. It is insoluble in
alcohol, but is dissolved by dilute acids with effervescence.
Magnesium carbonate is a GRAS substance under the provisions
of the Code of Federal Regulations as miscellaneous and/or gen eral purpose food additives. Magnesium carbonate is listed as GRAS substances migrating to food from paper and paperboard
products used in food packaging.
As a general purpose food additive, magnesium carbonate is used
as alkali in adjusting the acidity of foods. In addition to the fore going, magnesium carbonate, the most widely used magnesium
salt, serves as a drying agent, bleach ingredient, anticaking agent
and carrier for other additives. Other uses of magnesium salts
include firming agents, lubricants, flavor enhancers, and process ing aids. Pharmaceutically, carbonate is used as antacids.
Magnesium is an essential nutrient for plants and animals and is
a natural constituent of fruits, vegetables, grain, meats and sea foods. It is the fourth most abundant cation in the human body
and the second most plentiful intracellularly. The average 60-kg
human adult body contains about 24 g magnesium of which about
one-half resides in bone. Although plasma levels vary between 1.7
and 3 .0 mg per dl, very little is contained in extracellular fluid.
Magnesium is essential for the production and transfer of energy,
for protein, fat, and nucleic acid synthesis, for contractility in
muscle and excitability in nerve, and for the activity of numerous
enzyme systems.
