Calcium stearate: Chemical properties, Applications and Side Effects

Chemical properties

Calcium stearate is a compound consisting of calcium oxide with solid fatty acids such as stearic acid and palmitic acid (see Figure 1), which is widely used in food, pharmaceutical, chemical and cosmetic industries. Its chemical properties are as follows:

Chemical formula: C36H70Ca04

Molecular weight: 607.02

Appearance: white powder

Melting point: 155 °C

Density: 1.08g/cm3

Odour: Slight, distinctive fat odour

Solubility: insoluble in most solvents, only slightly soluble when heated in aromatic compounds, chlorinated hydrocarbons or vegetable oils, mineral oils and waxes.

Applications

Calcium stearate is mainly used in following ways:

(1) Food additives

Calcium stearate is an FDA-approved safe and edible ingredient that is primarily used as a dough conditioner, often in conjunction with other dough softeners such as mono- and diglycerides. It is also used as an emulsifier, flavouring agent, dusting agent, stabilizer, release agent and thickener.

(2) Pharmaceuticals

In the pharmaceutical industry, calcium stearate is used as a pharmaceutical excipient for lubricants in tablets and capsules

(3) Chemical industry

Calcium stearate is a versatile inorganic compound that is mainly used as a release agent, lubricant and acid scavenger in the rubber and tyre industries. It is also used as a stabiliser for PVC resins, as a water repellent for fabrics/cement/mortar/explosives, and as a levelling agent in paints.

(4) Cosmetic field

Calcium stearate is mainly used as a colouring agent and anti-caking agent in cosmetics. It is also used as a thickener and stabiliser. In the cosmetic industry, calcium stearate is used as a thickener to improve product appearance and reduce friction. When combined with certain types of fatty acids, it can also produce soap.

Side Effects

Calcium stearate is well tolerated in most cases in food applications with no serious adverse reactions. Overdosage may cause gastroenteritis with abdominal pain, nausea, vomiting and diarrhoea. Systemic reactions may follow, including symptoms such as tinnitus, dizziness, increased blood pressure, blurred vision and tremor.