E541 - Sodium aluminium phosphate

At a glance

• What it does: Helps batter and dough rise in the oven; helps processed cheese melt smoothly and slice well.
• Forms: An acidic form often labeled as acid sodium aluminium phosphate, and a basic form used mainly in cheese.
• Where it’s found: Baking powders, self-rising flour, pancake and cake mixes, biscuits, muffins, and some processed cheese slices and spreads.
• What it replaces: Other leavening acids or emulsifying salts when a slower, heat-activated rise or specific melt is desired.
• Nutrition note: Adds small amounts of aluminum, sodium, and phosphate; people limiting these should read labels.
• Regulatory note: In the U.S., both forms are “GRAS” (Generally Recognized As Safe) for specified uses. In the EU, E541 is authorized in selected food categories with restrictions.

Why is Sodium aluminium phosphate added to food?

Food makers use sodium aluminium phosphate (often shortened to SALP) to control when and how gas is released in a recipe. The acidic form reacts with baking soda (sodium bicarbonate) to release carbon dioxide, giving cakes, muffins, and biscuits a reliable oven rise without too much activity during mixing or storage.¹ The basic form acts as an emulsifying salt in processed cheese, helping proteins hold water and fat so the cheese melts and spreads evenly without separating.²

What foods contain Sodium aluminium phosphate?

You’ll most often see it in:

• Baking powders and self-rising flour
• Pancake, waffle, biscuit, and cake mixes
• Ready-to-bake refrigerated doughs
• Shelf-stable cakes and snack cakes
• Processed cheese slices, cheese foods, and cheese spreads

On labels, look for “sodium aluminum phosphate,” “SALP,” “E541,” or a specific subtype such as “acid sodium aluminum phosphate.”

What can replace Sodium aluminium phosphate?

Alternatives depend on the job you need it to do:

• As a leavening acid in baking: monocalcium phosphate, disodium diphosphate (often called sodium acid pyrophosphate), glucono-delta-lactone, or citric acid in some quick breads.
• As an emulsifying salt in processed cheese: sodium phosphates or sodium citrates.
• For thickening or stabilization roles: xanthan gum or mono- and diglycerides depending on the formulation.

Each substitute changes flavor release, texture, and timing, so recipes may need testing.

How is Sodium aluminium phosphate made?

Manufacturers produce SALP by reacting sources of sodium, aluminum, and phosphate under controlled conditions, then drying and milling the product to a consistent particle size. The acidic and basic forms are created by adjusting the proportions and processing so they perform differently in food systems. In baking, the acidic form is designed to be mostly heat-activated, while the basic form is optimized for cheese emulsification.

Is Sodium aluminium phosphate safe to eat?

• United States: The Food and Drug Administration (FDA) classifies both acidic and basic sodium aluminum phosphate as GRAS—Generally Recognized As Safe—when used for their intended purposes in food.¹²
• European Union: Aluminum-containing additives, including E541, are permitted only in certain foods and levels, and their contribution to total aluminum intake is considered within a weekly guidance value set by the European Food Safety Authority (EFSA). EFSA established a tolerable weekly intake (TWI) for aluminum of 1 mg per kg of body weight from all dietary sources.³

For most people eating a varied diet, SALP at regulated levels is considered safe. As with any aluminum-containing additive, total intake from all foods matters, not just one ingredient.

Does Sodium aluminium phosphate have any benefits?

• Baking quality: It provides a dependable, oven-timed rise that improves volume and crumb uniformity, especially in mixes that need a longer shelf life.
• Flavor control: Properly balanced SALP systems have a neutral to mild taste and help avoid early gas loss that can make baked goods dense.
• Cheese functionality: In processed cheese, it promotes smooth melt and spread and reduces oiling off during heating.

These are technological benefits; they are not health benefits.

Who should avoid Sodium aluminium phosphate?

• People advised to limit aluminum: Those with reduced kidney function may retain aluminum more readily and should follow medical advice about aluminum sources in diet and medicines.⁴
• Young children with high intake of baked snacks: Because EFSA’s TWI covers aluminum from all foods, frequent consumption of aluminum-raised baked goods can contribute meaningfully to weekly intake; moderation helps stay within guidance.³
• People on sodium- or phosphate-restricted diets: SALP adds both; check labels and consult a clinician or dietitian if you have kidney disease or need strict control.

Myths & facts

• Myth: All aluminum additives act the same. Fact: SALP comes in acidic and basic forms with different roles in baking and cheese.
• Myth: SALP always causes metallic flavors. Fact: At proper levels and with correct partners, SALP is formulated to minimize off-tastes in finished foods.
• Myth: Eating foods with SALP leads to aluminum build-up in everyone. Fact: In healthy people the gut absorbs very little aluminum, and the kidneys remove most of what is absorbed.⁴

Sodium aluminium phosphate in branded foods

• Where to look: Check ingredient lists on baking powders, self-rising flour, pancake and cake mixes, refrigerated doughs, and processed cheese slices or spreads.
• How it’s listed: “Sodium aluminum phosphate,” “acid sodium aluminum phosphate,” “basic sodium aluminum phosphate,” “SALP,” or “E541.”
• Shopping tips: If you prefer aluminum-free baking powders, many products are labeled as such. For cheese, compare labels to find products that use citrate or phosphate-only emulsifying salts.

References

Footnotes

1. Acid sodium aluminum phosphate (GRAS) — U.S. FDA, 21 CFR 182.1781. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-182/subpart-B/section-182.1781 ↩ ↩²

2. Basic sodium aluminum phosphate (GRAS) — U.S. FDA, 21 CFR 182.1783. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-182/subpart-B/section-182.1783 ↩ ↩²

3. Safety of aluminium from dietary intake (TWI 1 mg/kg bw/week) — EFSA Scientific Opinion. https://efsa.europa.eu/en/efsajournal/pub/754 ↩ ↩²

4. Toxicological Profile for Aluminum — ATSDR/CDC. https://www.atsdr.cdc.gov/toxprofiles/tp22.pdf ↩ ↩²