Sodium alginate, a common food additive, is primarily composed of the sodium salt form of alginic acid, belonging to the category of biopolymers of polysaccharides. Possessing desirable characteristics such as non-toxicity, biodegradability, and biocompatibility, sodium alginate finds extensive applications in various industries, including food, medicine, textiles, printing and dyeing, papermaking, and daily chemicals. Recently, it has gained recognition in the health sector, adding to its multifaceted value.

What is Sodium Alginate?

Sodium alginate (SA) is a natural polysaccharide extracted from brown seaweed, like kelp. It is obtained through extraction and purification with dilute alkali, resulting in a white or light yellow powder with no taste or odor. SA is hygroscopic, insoluble in organic solvents such as ethanol and ether, but soluble in hot and cold water. It acts as a hydrophilic gelling agent with excellent hydration ability, being non-toxic, highly expandable, flexible, and exhibiting good thickening and stability.

Uses of Sodium Alginate

1. Food Industry:

   • In cake and bread premixes, adding 0.1%-0.5% of sodium alginate prevents aging and drying, enhances taste, and improves gas retention properties, increasing volume and maintaining internal structure.
   • As a stabilizer in frozen milk, it improves taste without stickiness. In yogurt, 0.2%-1% sodium alginate maintains curd shape and prevents viscosity reduction during high-temperature sterilization, extending storage time.
   • Production of sodium alginate calcium gel can be used as a fresh-keeping film for fish, meat, and fruit foods, preventing enzymatic oxidation and dehydration.

2. Textile Industry:

   • Sodium alginate's water-soluble solution exhibits strong water absorption, ensuring fabrics have commendable water absorption performance.
   • The stability of the solution prevents deformation or damage to raw cellulose materials during production, reflecting environmental friendliness.
   • Fabrics made from sodium alginate have good air permeability, softness, and resistance to wrinkling.

Advantages in the Health Field

1. Stomach Diseases:

   • Sodium alginate reacts with gastric acid to form a mucous barrier, preventing gastric acid reflux into the esophagus and alleviating symptoms of gastroesophageal reflux disease.
   • Unlike proton pump inhibitors, sodium alginate does not cause long-term inhibition of gastric acid secretion, avoiding related side effects.

2. Trauma and Other Applications:

   • Sodium alginate can increase blood volume, stabilize the circulatory system, and treat dehydration caused by various conditions, such as bleeding shock, burn shock, and acute dysentery.
   • It has therapeutic effects on excreting cholesterol, protecting the intestines and stomach, aiding weight loss, and reducing blood sugar.