E500 - Sodium carbonates

At a glance

• What it is: A family of sodium salts used to control acidity and create lift in baked goods.
• Also called: Sodium carbonate, sodium bicarbonate (baking soda), sodium sesquicarbonate; E500(i), E500(ii), E500(iii).
• What it does: Works as a leavening agent and acidity regulator; helps texture and browning in baking.
• Common in: Cakes, cookies, crackers, breads, tortillas, and effervescent mixes.
• Dietary note: Adds some sodium to the diet.
• Regulation: Authorized in the EU with defined purity and composition rules.

Why is Sodium carbonates added to food?

Sodium carbonates are added because they regulate pH (acidity/alkalinity) and release carbon dioxide gas that makes baked goods rise. In the EU, E500 covers three forms: sodium carbonate (E500(i)), sodium hydrogen carbonate or baking soda (E500(ii)), and sodium sesquicarbonate (E500(iii)).¹ These forms are widely used as acidity regulators and leavening agents in foods across many categories.²

When mixed with an acid (like cream of tartar or citric acid) and moisture, baking soda starts to release carbon dioxide. Heat accelerates the reaction, creating bubbles that expand the dough or batter for a lighter texture.

What foods contain Sodium carbonates?

You can find sodium carbonates in:

• Baked goods such as cakes, muffins, cookies, biscuits, tortillas, and crackers
• Breadings, batters, and some extruded snacks
• Pancake and waffle mixes, and other “self-rising” flour mixes
• Effervescent beverages and candies that fizz when dissolved
• Some cocoa or chocolate products that have been alkalized for milder taste

On ingredient lists, look for “sodium carbonate,” “sodium bicarbonate,” “sodium sesquicarbonate,” “baking soda,” or “E500.”

What can replace Sodium carbonates?

Alternatives depend on the recipe and the reason you’re using E500:

• For lower sodium leavening, bakers sometimes use potassium carbonates.
• For quick lift in certain cookies or crackers, some formulas use ammonium carbonates.
• In complete leavening systems (“baking powder” style), the alkaline part (often sodium bicarbonate) pairs with acids such as disodium diphosphate, sodium aluminium phosphate, or monocalcium phosphate.

Remember: switching leavening agents may change taste, spread, and texture. You may also need to balance the formula’s acidity.

How is Sodium carbonates made?

Food-grade sodium carbonate is produced either by refining natural soda ash (from trona ore) or by the Solvay (ammonia-soda) process, which converts salt and limestone into sodium carbonate via several steps.³ The food additive must meet identity and purity specifications set in EU law for E500, including which forms are allowed and how they are described.¹

Sodium bicarbonate (E500(ii)) is typically made from carbonating a purified sodium carbonate solution under controlled conditions, then filtering and drying the crystals for food use.³

Is Sodium carbonates safe to eat?

Based on a comprehensive review, the European Food Safety Authority (EFSA) concluded there is no safety concern for sodium carbonates (E500) at the reported uses and use levels in food.² As with many minerals and salts, normal use in foods contributes some sodium to the diet, but the additive itself does not raise unique safety issues at authorized levels.

In the EU, E500 must comply with strict composition and purity specifications, which help ensure consistent quality across products.¹

Does Sodium carbonates have any benefits?

Yes. In baking, sodium carbonates help dough rise, create an open crumb, and improve tenderness. By raising pH, they can also reduce sourness and encourage browning, giving baked goods a pleasing color and flavor. In fizzy mixes, they are part of the reaction that produces the characteristic effervescence.

Who should avoid Sodium carbonates?

Most people can consume foods with E500 as part of a normal diet. However, if you are on a sodium-restricted diet (for example, for high blood pressure or certain kidney conditions), consider the total sodium from all sources, including additives like E500.⁴ Checking labels and serving sizes can help you stay within your recommended sodium intake.

Myths & facts

• Myth: “Baking soda and baking powder are the same.”
  Fact: Baking powder contains baking soda plus one or more acids and a filler; baking soda alone needs an acid in the recipe.
• Myth: “It only works when heated.”
  Fact: Baking soda starts to react with acid once it’s wet; heat speeds the reaction and gas expansion.
• Myth: “All sodium additives are just table salt.”
  Fact: Sodium carbonates are different compounds; they don’t taste salty, though they do add some sodium.
• Myth: “It’s synthetic only.”
  Fact: Sodium carbonate also exists in nature as soda ash from mineral deposits, which can be refined for use.³

Sodium carbonates in branded foods

On packages, E500 can appear as “sodium carbonate,” “sodium bicarbonate,” “sodium sesquicarbonate,” “baking soda,” “E500,” “E500(i),” “E500(ii),” or “E500(iii).” You’ll most often see it in baked goods, mixes, and effervescent products. If you want to limit sodium, compare labels and choose products with less total sodium per serving.

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 — European Commission. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32012R0231 ↩ ↩² ↩³

2. Re-evaluation of sodium carbonates (E 500) as food additives — European Food Safety Authority (EFSA Journal, 2018). https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2018.5209 ↩ ↩²

3. Soda Ash (Sodium Carbonate): Mineral Commodity Summaries — U.S. Geological Survey. https://pubs.usgs.gov/periodicals/mcs2023/mcs2023-soda-ash.pdf ↩ ↩² ↩³

4. Sodium and Food Sources — Centers for Disease Control and Prevention. https://www.cdc.gov/salt/food.htm ↩