E365 - Sodium fumarate

At a glance

• E-number: E365 (sodium fumarate)
• What it does: Helps control acidity (acts as an acidity regulator) and adds a tart note
• Where it appears: Used internationally in a range of processed foods
• What it is: The sodium salt of fumaric acid

Why is Sodium fumarate added to food?

Food makers use sodium fumarate mainly as an acidity regulator. That means it helps set and hold a target pH so flavor, color, and texture stay consistent over time.¹ In international standards, sodium fumarate is listed as an acidity regulator (sometimes called an acidulant or buffer), a role shared with acids like citric acid and malic acid.¹

What foods contain Sodium fumarate?

You may find sodium fumarate in categories such as beverages, flavored waters, confectionery, bakery items, and sauces, depending on local rules and the recipe needs.¹ Codex (the joint Food and Agriculture Organization and World Health Organization system for global food standards) lists sodium fumarate in the General Standard for Food Additives (GSFA) across multiple food categories as an acidity regulator.¹

What can replace Sodium fumarate?

Depending on the product and target taste, formulators might use:

• Fumaric acid for a stronger, more persistent tartness
• Citric acid for a bright, citrus-like acidity
• Malic acid for a smoother, lingering sourness
• Buffering salts such as sodium citrates or sodium malates to stabilize pH
• Potassium fumarate when reducing sodium content is important
• Other acids common in specific foods, such as phosphoric acid in some soft drinks

How is Sodium fumarate made?

Sodium fumarate is the simple sodium salt of fumaric acid. In practice, manufacturers neutralize food-grade fumaric acid with a sodium base (for example, sodium carbonate or sodium hydroxide), then filter, crystallize, and dry the product for food use. Its identity as the sodium salt of fumaric acid is documented by U.S. National Institutes of Health chemical records.²

Is Sodium fumarate safe to eat?

In the European Union (EU), sodium fumarate is an authorized food additive with the number E365 under the framework set by Regulation (EC) No 1333/2008.³ Its identity and purity criteria are set out in Commission Regulation (EU) No 231/2012, which lays down specifications that manufacturers must meet (for example, assay limits and impurity controls).⁴ As with any acidity regulator, actual use must follow applicable category permissions and good manufacturing practice.

Does Sodium fumarate have any benefits?

• Flavor control: Delivers a clean, tart profile without strong off-notes.
• pH stability: Helps keep products within a desired acidity range, supporting consistent taste, color, and texture.
• Formulation flexibility: Can complement or partially replace stronger acids to fine-tune sourness.

Who should avoid Sodium fumarate?

• People on sodium-restricted diets may wish to check labels, since this ingredient contributes a small amount of sodium.
• Anyone advised by a healthcare professional to limit specific additives should follow that guidance.

Myths & facts

• Myth: “All E-numbers are unsafe.” Fact: E-numbers are simply codes the EU uses for approved additives; safety is evaluated before approval and monitored afterward.³
• Myth: “Sodium fumarate is a preservative.” Fact: Its primary role is acidity regulation; any shelf-life benefit comes from pH control, not direct antimicrobial action.¹
• Myth: “It always makes foods taste very sour.” Fact: It provides tartness but is often used in blends to fine-tune flavor balance.

Sodium fumarate in branded foods

On ingredient lists, look for “sodium fumarate” or “E365.” It may appear alongside other acids or buffers, such as citric acid or sodium citrates, used to target a specific pH or taste. Availability and allowed uses can vary by country, so the same product sold in different markets may use different acidulants.

References

Footnotes

1. Sodium fumarate (INS 365) — Codex General Standard for Food Additives (GSFA). https://www.fao.org/gsfaonline/additives/details.html?id=365 ↩ ↩² ↩³ ↩⁴ ↩⁵

2. Sodium fumarate — PubChem, National Center for Biotechnology Information (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/Sodium-fumarate ↩

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

4. Commission Regulation (EU) No 231/2012 laying down specifications for food additives — EUR-Lex. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩