What is Sodium Citrate?
Sodium citrate or Trisodium citrate is an inorganic compound that has the molecular formula of Na3C6H5O7. In total, there are one molecule of citrate and three molecules of sodium ionically bound together in one molecule sodium citrate. In solution sodium exhibits a positive (+1) charge while citrate exhibits a negative (-3) charge. Per gram of sodium citrate, about 0.27 grams is sodium and 0.73 grams is citrate. Sodium citrate is also known as the salt form of citric acid.
Sources and Manufacturing
Sodium citrate is manufactured commercially through a series of chemical reactions. It requires the use of citric acid and sodium hydroxide. Essentially, sodium hydroxide is added to water where it is dissolved. Once the appropriate amount of sodium hydroxide is dissolved, citric acid is added to this solution at an appropriate rate. Then through a series of heating, cooling, and evaporation cycles, sodium citrate crystals are isolated.
Qualities
Sodium citrate has a slightly salty flavor that is also subtly citrus or tart. The primary uses of sodium citrate is as a flavoring agent as well as preservative in foods.
Sodium citrate can also be used in some sport nutrition products as an appreciable source of sodium. Because it is less salty than sodium chloride, sodium citrate is sometimes used in favor of sodium chloride as a sodium source to make the flavor profile of a product more favorable.
Sodium citrate also makes for a great emulsifying agent in some food products preventing the separation of fats and oils from the rest of the product. This is made possible by the hydrophilic and lipophilic properties of sodium citrate’s molecular structure.
Because sodium citrate is a salt of citric acid, when dissolved in solution sodium citrate can act as a conjugate base or buffering agent (acidity regulator) that stabilizes the pH of a solution against decreases in pH when an acid is added.
Other Uses
Sodium citrate also has uses in the medical field. For example, sodium citrate can be used as an anticoagulation agent, which is important in situations where blood is transfused or when blood is stored in blood banks. Specifically, the citrate ion acts to bind the calcium in blood preventing the coagulation process. Sodium citrate can also be used to help treat some acute kidney diseases, kidney stones, and urinary tract infections. It can also be used to help treat metabolic acidosis due to its buffering capabilities.
In industrial settings, sodium citrate is used as a cleaning agent to help remove chemical residues.
Sodium Citrate in Carbs Fuel Products
Sodium citrate is used in the Original Gel and the Sport Drink Mix. In the Original Gel, sodium citrate plays triple duty. First, it acts as a source of sodium to replenish the sodium lost through sweat. Second, it acts as a flavoring agent to provide a light citrus flavor. Third, it acts as an acidity regulator to help manage the pH of the gel so that the ideal pH can be achieved for long-term shelf stability. In the Sport Drink Mix, sodium citrate is used as one of the primary sources of sodium as well as a flavoring agent to provide a slight citrus and tart flavor profile.
