Potassium alginate occurs as a white to yellowish, fibrous or
granular powder; it is almost odorless and tasteless.
Occurs in filamentous, grainy, granular,
and powdered forms. It is colorless or slightly yel-
low and may have a slight characteristic smell and
taste. Slowly soluble in water, forming a viscous
solution; insoluble in alcohol.
Potassium Alginate is a gum that is the potassium salt of alginic acid. It is soluble in cold water, forming a viscous colloidal solution. It functions as a stabilizer, thickener, and gelling agent. It is used in dietetic foods, low-sodium foods, dry mixes, and dental impression material. Typical usage levels range from 0.05 to 0.50%.
Thickening agent and stabilizer in dairy prod-
ucts, canned fruits, and sausage casings; emulsifier.
See alginic acid.
Alginate obtained from brown seaweed is subjected to demineralization,
extraction, and precipitation of alginic acid. Following
neutralization, the potassium alginate obtained is dried and milled.
Hydrophilic colloid
having a molecular weight of 32,000–250,000.
Pharmaceutical Applications
Potassium alginate is widely used in foods as a stabilizer, thickener,
and emulsifier; however, its use as a pharmaceutical excipient is
currently limited to experimental hydrogel systems. The viscosity,
adhesiveness, elasticity, stiffness, and cohesiveness of potassium
alginate hydrogels have been determined and compared with values
from a range of other hydrogel-forming materials.The effect of
calcium ions on the rheological properties of procyanidin hydrogels
containing potassium alginate and intended for oral administration
has also been investigated.
Potassium alginate is widely used in food products. It is currently
used as an excipient only in experimental pharmaceutical formulations.
In the solid state, potassium alginate is a stable material that is not
prone to microbial spoilage. Over time, a slow reduction in the
degree of polymerization can occur, which may be reflected in a
reduction in the viscosity of solutions. As both temperature and
moisture can impair the performance of potassium alginate, storage
below 25°C is recommended.
Potassium alginate solutions are stable at pH 4–10; long-term
storage outside this range can result in depolymerization of the
polymer through hydrolysis. Gelation or precipitation of the
alginate can occur at pH values less than 4. Liquid or semisolid
alginate formulations should be preserved: suitable preservatives
are sodium benzoate, potassium sorbate, or parabens.
Potassium alginate should be stored under cool, dry conditions
in a well-closed container.
Incompatible with strong oxidizers.
GRAS listed. Accepted for use in foods in the USA and Europe.
