Name: Sodium Propionate
CAS No: Propionic acid, sodium salt, hydrate [6700-17-0], Propionic acid, sodium salt, anhydrous [137-40-6],
BP: Sodium Propionate PhEur: Sodium Propionate USP-NF: Sodium Propionate
E281; ethylformic acid, sodium salt, hydrate; methylacetic acid, sodium salt, hydrate; natrii propionas; sodium propanoate hydrate; sodium propionate hydrate
Propionic acid, sodium salt, hydrate [6700-17-0], Propionic acid, sodium salt, anhydrous [137-40-6],
C3H5NaO2xH2O 114.06 (for monohydrate) C3H5NaO2 96.06 (for anhydrous)
As an excipient, sodium propionate is used in oral pharmaceutical formulations as an antimicrobial preservative. Like propionic acid, sodium propionate and other propionic acid salts are fungistatic and bacteriostatic against a number of Gram-positive cocci. Propionates are more active against molds than is sodium benzoate, but have essentially no activity against yeasts; see Section 10. Therapeutically, sodium propionate has been used topically in concentrations up to 10% w/w alone or in combination with other propionates, caprylates, or other antifungal agents, in the form of ointments or solutions for the treatment of dermatophyte infections. Eye drops containing 5% w/v sodium propionate have also been used. See Section 18. In food processes, particularly baking, sodium propionate is used as an antifungal agent; it may also be used as a flavoring agent in food products. In veterinary medicine, sodium propionate is used therapeutically as a glucogenic substance in ruminants.(1)
Sodium propionate occurs as colorless transparent crystals or as a granular, free-flowing, crystalline powder. It is odorless, or with a slight characteristic odor, and is deliquescent in moist air. Sodium propionate has a characteristic, slightly cheeselike taste, although by itself it is unpalatable.
See Table I.
Antimicrobial activity Sodium propionate, propionic acid, and other propionates possess mainly antifungal activity and are used as preservatives primarily against molds; they exhibit essentially no activity against yeasts. Although, in general, propionates exhibit little activity against bacteria, sodium propionate is effective against Bacillus mesenterium, the organ-ism that causes ‘rope’ in bread. Antimicrobial activity is largely dependent upon the presence of the free acid and hence propionates exhibit optimum activity at acid pH, notably at less than pH 5. Synergistic effects occur between propionates and carbon dioxide or sorbic acid. See also Propionic acid. NIR spectra see Figure 1. Solubility Soluble 1 in 24 of ethanol (95%), 1 in 1 of water, and 1 in 0.65 of boiling water; practically insoluble in chloroform and ether.
Sodium propionate is deliquescent and should therefore be stored in an airtight container in a cool, dry place.
Incompatibilities for sodium propionate are similar to those of other weak organic acids.
Sodium propionate is prepared by the reaction of propionic acid with sodium carbonate or sodium hydroxide.
Sodium propionate and other propionates are used in oral pharmaceutical formulations, food products, and cosmetics. The free acid, propionic acid, occurs naturally at levels up to 1% w/w in certain cheeses. Following oral consumption, propionate is metabolized in mammals in a manner similar to that of fatty acids. Toxicity studies in animals have shown sodium propionate and other propionates to be relatively nontoxic materials.(2,3) In veterinary medicine, sodium propionate is used as a therapeutic agent for cattle and sheep.(1) In humans, 6 g of sodium propionate has been administered daily without harm.(2) However, allergic reactions to propionates can occur. LD50 (mouse, oral): 6.33 g/kg(4) LD50 (mouse, SC): 2.1 g/kg LD50 (rabbit, skin): 1.64 g/kg
Observe normal precautions appropriate to the circumstances and quantity of material handled. Sodium propionate may be irritant to the eyes and skin. Gloves, eye protection, and a dust-mask are recommended. When heated to decomposition, sodium propionate emits toxic fumes of sodium monoxide, Na2O.In the UK, the workplace exposure limits for propionic acid are 31 mg/m3 (10 ppm) long-term (8-hour TWA) and 46 mg/m3 (15 ppm) short-term.(5)
GRAS listed. Accepted for use as a food additive in Europe. In cheese products, propionates are limited to 0.3% w/w concentration; a limit of 0.32% w/w is applied in flour and white bread rolls, while a limit of 0.38% w/w is applied in whole wheat products. Included in the FDA Inactive Ingredients Database (oral capsules, powder, suspensions, and syrups). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.
Anhydrous sodium propionate; calcium propionate; potassium propionate; propionic acid; zinc propionate. Anhydrous sodium propionate Empirical formula C3H5O2Na Molecular weight 96.06 CAS number [137-40-6] Synonyms E281; propanoic acid, sodium salt, anhydrous. Safety LD50 (mouse, oral): 2.35 g/kg(4) LD50 (rat, oral): 3.92 g/kg Calcium propionate Empirical formula C6H10O4Ca Molecular weight 186.22 CAS number [4075-81-4] Synonyms Calcium dipropionate; E282; propanoic acid, calcium salt; propionic acid, calcium salt. Appearance White crystalline powder. Solubility Soluble in water; slightly soluble in ethanol (95%) and methanol; practically insoluble in acetone and benzene. Method of manufacture Prepared by the reaction of propionic acid and calcium hydroxide. Comments Occurs as the monohydrate or trihydrate. Potassium propionate Empirical formula C3H5O2K Molecular weight 112.17 CAS number [327-62-8] Synonyms E283; propanoic acid, potassium salt; propionic acid, potassium salt. Appearance White crystalline powder. Comments Occurs as the anhydrous form and the monohydrate. Decomposes in moist air to give off propionic acid. Zinc propionate Empirical formula C6H10O4Zn Molecular weight 211.52 CAS number [557-28-8] Synonyms Propanoic acid, zinc salt; propionic acid, zinc salt. Appearance White platelets or needlelike crystals (for the monohydrate). Solubility The anhydrous form is soluble 1 in 36 of ethanol (95%) at 158C, 1 in 6 of boiling ethanol (95%), and 1 in 3 of water at 158C. Method of manufacture Prepared by dissolving zinc oxide in dilute propionic acid solution. Comments Occurs as the anhydrous form and the monohydrate. Decomposes in moist air to give off propionic acid.
Propionates are used as antimicrobial preservatives in preference to propionic acid since they are less corrosive.The therapeutic use of sodium propionate in topical antifungal preparations has largely been superseded by a new generation of antifungal drugs. A specification for sodium propionate is contained in the Food Chemicals Codex (FCC).(6) The EINECS number for sodium propionate is 205-290-4. The PubChem Compound ID (CID) for sodium propionate is 23663426.