Sodium propionate

Sodium propionate^[1]
Names
	Preferred IUPAC name Sodium propanoate
	Other names Sodium propionate; Napropion; E281
Identifiers
CAS Number	137-40-6 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:132106 ;
ChEMBL	ChEMBL500826 ;
ChemSpider	8399 ;
ECHA InfoCard	100.004.810
EC Number	205-290-4;
E number	E281 (preservatives)
PubChem CID	2723816;
UNII	DK6Y9P42IN ;
CompTox Dashboard (EPA)	DTXSID7021996 ;
	InChI InChI=1S/C3H6O2.Na/c1-2-3(4)5;/h2H2,1H3,(H,4,5);/q;+1/p-1 Key: JXKPEJDQGNYQSM-UHFFFAOYSA-M ; InChI=1/C3H6O2.Na/c1-2-3(4)5;/h2H2,1H3,(H,4,5);/q;+1/p-1 Key: JXKPEJDQGNYQSM-REWHXWOFAH;
	SMILES [Na+].[O-]C(=O)CC;
Properties
Chemical formula	C3H5NaO2
Molar mass	96.060 g/mol
Appearance	Transparent crystals
Odor	faint acetic-butyric odor
Melting point	289 °C (552 °F; 562 K)
Solubility in water	1 g/mL
Solubility in ethanol	41.7 g/L
Pharmacology
ATC code	S01AX10 (WHO) QA16QA02 (WHO)
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H317, H318, H411
Precautionary statements	P261, P264, P264+P265, P270, P272, P273, P280, P301+P317, P302+P352, P305+P354+P338, P317, P321, P330, P333+P317, P362+P364, P391, P501
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	6332 mg/kg (mouse, oral)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Sodium propanoate or sodium propionate is the sodium salt of propionic acid which has the chemical formula Na(C₂H₅C O O). This white crystalline solid is deliquescent in moist air.^[2]

Structure

Anhydrous sodium propionate is a polymeric structure, featuring trigonal prismatic Na⁺ centers bonded to six oxygen ligands provided by the carboxylates. A layered structure is observed, with the hydrophobic ethyl groups projecting into the layered galleries. With hydrated sodium propionate, some of these Na-carboxylate linkages are displaced by water.

Preparation

It is produced by the reaction of propionic acid and sodium carbonate or sodium hydroxide.^[4]

Uses

It is used as a food preservative and is represented by the food labeling E number E281 in Europe; it is used primarily as a mold inhibitor in bakery products. It is approved for use as a food additive in the EU,^[5] USA^[6] and Australia and New Zealand^[7] (where it is listed by its INS number 281).

Reactions

Decomposition takes place via ketonization, yielding the symmetric ketone (3-pentanone) and sodium carbonate:^[4]

2Na(O₂CEt) → Na₂CO₃ + Et(CO)Et

Some side reactions resulting in the release of carbon dioxide are observed.^[4]

References

↑ Merck Index, 11th Edition, 8623.
1 2 3 PubChem. "Sodium Propionate". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-02-01.
↑ Fábry, Jan; Samolová, Erika (2020). "Layered alkali propanoates M+(C₂H₅COO)⁻; M⁺= Na⁺, K⁺, Rb⁺, Cs⁺". Acta Crystallographica Section E. 76 (9): 1508–1513. Bibcode:2020AcCrE..76.1508F. doi:10.1107/S2056989020011469. PMC 7472758. PMID 32939309.
1 2 3 Grivel, J. -C. (2018-11-01). "New insights into the thermal behavior and decomposition of sodium propionate". Journal of Analytical and Applied Pyrolysis. 136: 62–68. doi:10.1016/j.jaap.2018.10.023. ISSN 0165-2370.
↑ UK Food Standards Agency: "Current EU approved additives and their E Numbers". Retrieved 2011-10-27.
↑ US Food and Drug Administration: "Listing of Food Additives Status Part II". Food and Drug Administration. Archived from the original on January 8, 2010. Retrieved 2011-10-27.
↑ Australia New Zealand Food Standards Code"Standard 1.2.4 - Labelling of ingredients". 8 September 2011. Retrieved 2011-10-27.

External links

Sodium propanoate at Sci-toys.com

[1] Merck Index, 11th Edition, 8623.

[PubChem-2] 1 2 3 PubChem. "Sodium Propionate". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-02-01.

[3] Fábry, Jan; Samolová, Erika (2020). "Layered alkali propanoates M+(C₂H₅COO)⁻; M⁺= Na⁺, K⁺, Rb⁺, Cs⁺". Acta Crystallographica Section E. 76 (9): 1508–1513. Bibcode:2020AcCrE..76.1508F. doi:10.1107/S2056989020011469. PMC 7472758. PMID 32939309.

[Grivel-4] 1 2 3 Grivel, J. -C. (2018-11-01). "New insights into the thermal behavior and decomposition of sodium propionate". Journal of Analytical and Applied Pyrolysis. 136: 62–68. doi:10.1016/j.jaap.2018.10.023. ISSN 0165-2370.

[5] UK Food Standards Agency: "Current EU approved additives and their E Numbers". Retrieved 2011-10-27.

[6] US Food and Drug Administration: "Listing of Food Additives Status Part II". Food and Drug Administration. Archived from the original on January 8, 2010. Retrieved 2011-10-27.

[7] Australia New Zealand Food Standards Code"Standard 1.2.4 - Labelling of ingredients". 8 September 2011. Retrieved 2011-10-27.

[2]