E431 - Polyoxyethylene (40) stearate

At a glance

• What it is: A nonionic emulsifier made by attaching a polyethylene glycol (PEG) chain to stearic acid (a fatty acid).
• What it does: Helps mix oil and water, stabilizes foams, and improves texture.
• Where you might see it: Certain desserts, toppings, sauces, and confectionery.
• Label names: “Polyoxyethylene (40) stearate,” “PEG-40 stearate,” or “E431.”
• Regulation: Authorized in the EU as food additive E431 with defined identity and purity criteria.¹²

Why is Polyoxyethylene (40) stearate added to food?

Food makers use E431 to keep oil and water mixed and to stabilize foams. In practice, that means smoother sauces that don’t separate, whipped toppings that hold their shape, and ice creams or desserts with a consistent texture. As a nonionic surfactant, it works across a wide pH range and in salty or sugary systems, which makes it versatile in many recipes.

What foods contain Polyoxyethylene (40) stearate?

You may find E431 in:

• Whipped toppings and dessert foams
• Certain sauces, dressings, and ready-to-eat meals
• Some confectionery, fillings, and glazed or coated treats
• Powdered mixes where quick dispersion and stable emulsions are needed

Its use varies by country and by product style. Always check ingredient lists for “polyoxyethylene (40) stearate,” “PEG-40 stearate,” or “E431.”

What can replace Polyoxyethylene (40) stearate?

Depending on the recipe, formulators may switch to:

• Other emulsifiers: mono- and diglycerides of fatty acids, sucrose esters of fatty acids, polyglycerol polyricinoleate, or sorbitan monostearate
• Polysorbates: for example, polysorbate 20, polysorbate 60, or polysorbate 80
• Stabilizers and thickeners to support texture: lecithins, xanthan gum, or gum arabic

The best choice depends on taste, mouthfeel, processing conditions, and labeling goals.

How is Polyoxyethylene (40) stearate made?

E431 is produced by esterifying stearic acid (a common fatty acid from vegetable or animal fats) with polyethylene glycol (PEG). The “(40)” indicates an average of about 40 ethylene oxide units in the PEG chain, which tunes the emulsifier’s water-loving and oil-loving balance. Food-grade E431 must meet official identity and purity criteria set in EU law.¹ It may also appear on labels and in technical documents under the synonym “PEG-40 stearate” or “polyoxyl (40) stearate.”³

Is Polyoxyethylene (40) stearate safe to eat?

In the European Union, polyoxyethylene (40) stearate is on the Union list of permitted food additives (E431) and must comply with specifications published by the European Commission. These specifications define what the additive is and set limits for impurities and composition to ensure it is suitable for food use.²¹

As with any additive, manufacturers are required to use no more than is necessary to achieve the intended effect, and products must meet all applicable food safety laws.²

Does Polyoxyethylene (40) stearate have any benefits?

Yes—primarily for food quality:

• Helps oil and water stay mixed, reducing separation
• Stabilizes whipped and aerated textures
• Improves dispersion of powders and flavors
• Can make processing more consistent and predictable

These functional gains can reduce waste and maintain a product’s look and feel over shelf life.

Who should avoid Polyoxyethylene (40) stearate?

• People who prefer to avoid emulsifiers in general can choose products with simpler ingredient lists.
• Individuals with a known sensitivity to polyethylene glycols (PEGs) should consult a healthcare professional and check labels.
• Strict vegetarians, vegans, or those with religious dietary rules may want to confirm the stearic acid source (vegetable vs animal) with the manufacturer.

Myths & facts

• “It’s antifreeze.” Fact: Antifreeze typically contains ethylene glycol, a small molecule. E431 is a different substance built from long polyethylene glycol chains reacted with a fatty acid. They are not the same.
• “It’s a plastic.” Fact: E431 is a surfactant-type emulsifier. While it contains polymeric PEG, in foods it serves a functional purpose at low levels and must meet food-grade specifications.¹
• “It’s just cosmetic.” Fact: Emulsifiers like E431 can make real differences in product stability, texture, and consistency that consumers notice.

Polyoxyethylene (40) stearate in branded foods

On ingredient lists, look for “polyoxyethylene (40) stearate,” “PEG-40 stearate,” or its E-number “E431.” If you prefer to avoid it, check labels on whipped toppings, desserts, sauces, confectionery, and certain instant or ready-to-use mixes.

References

Footnotes

1. Commission Regulation (EU) No 231/2012 laying down specifications for food additives listed in Annexes II and III to Regulation (EC) No 1333/2008. EUR-Lex. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩² ↩³ ↩⁴

2. Regulation (EC) No 1333/2008 on food additives. EUR-Lex. https://eur-lex.europa.eu/eli/reg/2008/1333/oj ↩ ↩² ↩³

3. Polyethylene glycol 40 stearate — PubChem (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/23667465 ↩