Saccharin

• BPSaccharin
• JPSaccharin
• Ph. Eur.Saccharin
• USP–NFSaccharin

1,2-benzisothiazol-3(2H)-one 1,1-dioxide; benzoic sulfimide; o-benzosulfimide; gluside; insoluble saccharin; saccharinum; E954

1,2-Benzisothiazol-3(2H)-one 1,1-dioxide · [81-07-2]

UNII FST467XS7D · PubChem CID 5143

C7H5NO3S · 183.18

Sweetening agent

Typical concentrations: — · Dosage forms: Liquid, Solid

An intense sweetener, about 300–600 times as sweet as sucrose, used in beverages, foods, table-top sweeteners and oral products such as tablets, powders, mouthwashes and dentifrices. Its bitter, metallic aftertaste at higher concentrations is often masked by combining it with other sweeteners. Typical concentrations are about 0.02–0.5% w/w; because of its poor water solubility, the more soluble saccharin salts are usually preferred in liquids.

White crystals or a white crystalline powder, odourless or with a faint aromatic odour. It has an intensely sweet taste, with a metallic or bitter aftertaste noticeable at higher concentrations.

Melting point

226–230 °C

pKa

≈ 1.6 (a fairly strong acid)

Solubility

slightly soluble in water (about 1 in 290); sparingly soluble in ethanol; dissolves in dilute solutions of alkali hydroxides and carbonates, forming salts

Relative sweetness

about 300–600 times that of sucrose

Stable under the normal conditions used in formulation. Significant decomposition occurs only at high temperatures in strongly acidic solution, when it slowly hydrolyses to 2-sulfamoylbenzoic acid and related compounds. Store in a well-closed container in a dry place.

No major incompatibilities are reported. As an acid it reacts with bases to form salts, and it should be kept away from strong oxidising agents.

Made either from toluene, via o-toluenesulfonyl chloride and o-toluenesulfonamide, which is oxidised and cyclised (Remsen–Fahlberg process), or from methyl anthranilate by diazotisation followed by reaction with sulfur dioxide, chlorine and ammonia (Maumee process).

Saccharin is not metabolised and is excreted unchanged in the urine. Bladder tumours seen in male rats fed very high doses arise by a mechanism not considered relevant to humans, and it was removed from the US list of potential carcinogens in 2000. JECFA has set an acceptable daily intake of 0–5 mg/kg body weight for saccharin and its salts. Hypersensitivity and photosensitivity reactions have been reported rarely.

Observe normal precautions for the quantity handled. Eye protection and gloves are recommended.

Permitted as a sweetener in foods in the USA under interim food-additive regulations. Accepted in Europe as a food additive (E954). Included in the FDA Inactive Ingredient Database (oral preparations) and in non-parenteral medicines licensed in Europe.

Acesulfame potassium; aspartame; saccharin calcium; saccharin sodium; sucralose.

Saccharin is often blended with cyclamate, aspartame or acesulfame potassium, which gives a more sugar-like taste profile than any one sweetener alone. In solid dosage forms the free acid is acceptable, but for liquids the sodium salt is easier to formulate.