SODIUM PROPIONATE

Chemical Properties

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.

Uses

Pharmaceutic aid (preservative).

Uses

Sodium Propionate Hydrate is a food preservative used for its antifungal ability towards grain products.

Production Methods

Sodium propionate is prepared by the reaction of propionic acid with sodium carbonate or sodium hydroxide.

Pharmaceutical Applications

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.
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.
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.

Safety

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.
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
LD50 (mouse, SC): 2.1 g/kg
LD50 (rabbit, skin): 1.64 g/kg

storage

Sodium propionate is deliquescent and should therefore be stored in an airtight container in a cool, dry place.

Incompatibilities

Incompatibilities for sodium propionate are similar to those of other weak organic acids.

Regulatory Status

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.

Raw materials

Preparation Products