E342 - Ammonium phosphate

At a glance

• What it is: The ammonium salts of phosphoric acid (mono- and diammonium phosphate)
• What it does: Helps fermentation (yeast nutrient) and supports product stability and texture
• Where it’s found: Most commonly in fermented beverages; may appear in other processed foods
• Label names: Ammonium phosphate, monoammonium phosphate (MAP), diammonium phosphate (DAP), E342
• Dietary note: Contributes to total phosphorus intake

Why is Ammonium phosphate added to food?

Ammonium phosphate supplies ammonium and phosphate ions that yeast can use, so it’s often added as a nutrient during fermentation. This helps yeast start quickly and complete fermentation more reliably in beverages like wine and similar products.¹

It can also help maintain stable conditions in recipes alongside other phosphate salts, which is why you might see it used in small amounts in certain processed foods.²

What foods contain Ammonium phosphate?

You are most likely to encounter diammonium phosphate in fermented beverages, where it is used as a yeast nutrient (for example, in winemaking).¹ In the European Union (EU), E342 may also be authorized in selected food categories under additive rules, so it can appear at low levels in some processed foods; always check the ingredient list for “ammonium phosphate” or “E342.”³

What can replace Ammonium phosphate?

Possible substitutes depend on the job it is doing:

• For yeast nutrition in fermentation: ammonium sulphate or nutrient blends based on yeast extract
• For similar phosphate functions: phosphoric acid, sodium phosphates, potassium phosphates, calcium phosphates, or magnesium phosphates
• For more complex stabilization needs: selected polyphosphates

The best choice depends on local regulations and the specific food process.

How is Ammonium phosphate made?

Food-grade ammonium phosphate is produced by neutralizing purified phosphoric acid with ammonia. By adjusting the neutralization, manufacturers obtain either monoammonium phosphate or diammonium phosphate. The resulting salts are white, crystalline, and readily soluble in water.²⁴

Is Ammonium phosphate safe to eat?

In the EU, ammonium phosphates (E342) are regulated food additives with defined purity specifications and must be used only where permitted and at levels set by law.³² In the United States, diammonium phosphate is specifically allowed as a yeast nutrient in wine production under federal rules for materials used in winemaking.¹

As with all phosphate additives, E342 contributes to total phosphorus intake. Phosphorus is essential for bones and cells, but people who need to limit phosphorus (for medical reasons) should be mindful of phosphate additives in processed foods.⁵

Does Ammonium phosphate have any benefits?

For food makers, E342 supports reliable, complete fermentation by providing nutrients that yeast readily uses.¹ For consumers, it doesn’t offer a special health benefit on its own, though phosphorus itself is an essential mineral found widely in foods.⁶

Who should avoid Ammonium phosphate?

• People with chronic kidney disease (CKD) or those asked by their clinician to limit phosphorus should watch for phosphate additives, including E342, because these can add to phosphorus intake.⁵
• Anyone following a low-phosphorus diet for medical reasons should review labels for “ammonium phosphate,” “monoammonium phosphate,” “diammonium phosphate,” or “E342,” and discuss suitable alternatives with a healthcare professional.⁵

Myths & facts

• “Ammonium phosphate is the same as ammonium phosphatides.” False. E342 (ammonium phosphates) and ammonium phosphatides (E442) are different additives used for different purposes.
• “It will make foods smell like ammonia.” Not at the tiny amounts used under food rules. In proper use, you should not detect an ammonia smell in the finished product.
• “It always acts as a leavening agent.” Not necessarily. In practice, E342 is used most often as a yeast nutrient in fermentation rather than as a leavening acid.

Ammonium phosphate in branded foods

Manufacturers list this additive as “ammonium phosphate,” “monoammonium phosphate,” “diammonium phosphate,” or “E342” (in regions that use E-numbers). You can spot it most often in fermented beverages and occasionally in specialty processed foods where phosphates are permitted. If you are limiting phosphorus, scan ingredient lists and contact the brand’s customer service for the exact amount used.

References

Footnotes

1. 27 CFR §24.246 — Materials authorized for the treatment of wine and juice (includes diammonium phosphate as a yeast nutrient). https://www.ecfr.gov/current/title-27/part-24/section-24.246 ↩ ↩² ↩³ ↩⁴

2. Commission Regulation (EU) No 231/2012 — Specifications for food additives. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩² ↩³

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

4. Diammonium hydrogen phosphate — PubChem (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/24457 ↩

5. Phosphorus in diet — MedlinePlus (NIH/NLM). https://medlineplus.gov/ency/article/002424.htm ↩ ↩² ↩³

6. Phosphorus — NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Phosphorus-Consumer/ ↩