Sodium propanoate or sodium propionate is the sodium salt of propionic acid which has the chemical formula Na(C2H5COO). This white crystalline solid is deliquescent in moist air.
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, USA and Australia and New Zealand (where it is listed by its INS number 281).