Ammonium Sulfate

What is Ammonium Sulfate?

Ammonium sulfate, or [(NH₄)₂SO₄], is an inorganic crystalline salt used in wine, baking, sausage casing and other foods. Its addition to baked goods provides many benefits, including:

• Dough strengthening and conditioning
• Dough stabilizing
• Buffering
• Bread quality enhancing
• Yeast survival and growth

Origin and Commercial Production

Ammonium sulfate has been produced for over 150 years from ammonia released from coal coke. Today, it is produced from the heated reaction of ammonia and sulfuric acid:

2NH₃+H₂SO₄→(NH₄)₂SO₄

It can also be produced commercially as:¹

• By-product of caprolactam production
• Neutralization of ammonium hydroxide with sulfuric acid
• Precipitation from gypsum in ammonium carbonate solution

Properties²

This ingredient is a rich source of nitrogen (21%) and sulfur (24%). It is:

• Very soluble in water but insoluble in ethanol
• pH of 0.1 M solution is 5.5
• Imparts a slight salty taste

Function

In baked goods, this additive is widely used as a:

• Dough conditioner
• Surfactant
• Dough strengthener

Ammonium sulfate can also form ammonium metal sulfates or double salts when reacted with metal sulfates and slowly evaporates to yield the remaining salt particulates.

Application

Various baked goods such as pita, steamed bread, bagels, english muffins and buns all contain this ingredient.

In addition to its role in pH control in flour and baked goods, volume build up, consistency, crumb and shelf life improvement, this ingredient provides nitrogen for the yeast growth and survival.

FDA Regulation

Ammonium sulfate is a ‘GRAS’ additive. The FDA recommends a maximum level of 0.15% to comply with current Good Manufacturing Practices (21CFR184.1143).³
 

References

1. Speight, J. G. Industrial Inorganic Chemistry. In: Environmental Inorganic Chemistry for Engineers. Elsevier. 2017: 111–169.
2. Ammonium sulfate. https://pubchem.ncbi.nlm.nih.gov/compound/Ammonium-sulfate#section=2D-Structure. Accessed by Dec 19.2019.
3. CFR – Code of Federal Regulations 21CFR184.1143. Accessdata. Fda. gov. April 01. 2019. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=184.1143. Accessed by Dec 19. 2019.