Sodium benzoate (E211), also called benzoate of soda, has the
chemical formula NaC6H5CO2. It is the sodium salt of benzoic acid
and exists in this form when dissolved in water. It can be produced
by reacting sodium hydroxide with benzoic acid.
Sodium benzoate is a preservative. It is bacteriostatic and
fungistatic under acidic conditions. It is used most prevalently in
acidic foods such as salad dressings (vinegar), carbonated drinks
(carbonic acid), jams and fruit juices (citric acid), pickles
(vinegar), and condiments. It is also found in alcohol-based
mouthwash and silver polish. It can also be found in cough syrups
like Robitussin. [1] Sodium benzoate is declared on a product label
as 'sodium benzoate' or E211.
It is also used in fireworks as a fuel in whistle mix, a powder
which imparts a whistling noise when compressed into a tube and
ignited.
It is found naturally in cranberries, prunes, greengage plums,
cinnamon, ripe cloves, and apples. Concentration as a preservative
is limited by the FDA in the U. S. To 0.1% by weight though
organically-grown cranberries and prunes can conceivably contain
levels exceeding this limit. [citation needed] The International
Programme on Chemical Safety found no adverse effects in humans at
doses of 647-825 mg/kg of body weight per day.
Cats have a significantly lower tolerance against benzoic acid and
its salts than rats and mice. Sodium benzoate is, however, allowed
as an animal food additive at up to 0.1%, according to AFCO's
official publication.
Appearance | White Crystalline powder, columnar or global granular |
Identification | Positive |
Assay | 99.0~100.5% |
Loss on drying | ≤1.50% |
Sulphate | None |
Chloride | ≤0.02% |
Chloride compound | ≤0.03% |
Heavy Metals (as Pb) | ≤0.001% |
Arsenic | ≤0.0002% |
Mercury | ≤0.0001% |
Volatility | Up to the requirement |
Acidity and alkalinity | ≤0.20mL/g |
Clarity of Solution | Clear and colorless |
Water Solubility | 600 g/l (ref temperature 20 °C ) |
Benzene | ≤0.010% |
Chloroform | ≤0.005% |
1, 4-Dioxane | ≤0.010% |
Methylene Chloride | ≤0.050% |
Trichloroethylene | ≤0.010% |