What is the main protein in gluten? Unpacking gliadin and glutenin

November 15, 2025 •

2 min read

Roughly 85% of wheat's total protein consists of a complex network known as gluten. This network is composed of two primary proteins, gliadin and glutenin, and it is their unique properties and interactions that define the texture of baked goods. This article will delve into what is the main protein in gluten by exploring these two vital components.

Quick Summary

Gluten is formed from two main proteins, gliadin and glutenin, when wheat flour is mixed with water. Gliadin provides the extensibility, while glutenin contributes elasticity and strength to the dough.

Key Points

Dual Protein System: Gluten is a complex formed from two primary proteins, gliadin and glutenin.
Gliadin's Role: Gliadin provides dough with its viscosity and extensibility.
Glutenin's Role: Glutenin is responsible for the dough's elasticity and strength.
Network Formation: When flour and water are mixed, gliadin and glutenin interact to create the three-dimensional gluten network.
Celiac Trigger: Gliadin's resistance to digestion can trigger the autoimmune response in celiac disease.
Baking Quality: The ratio of gliadin to glutenin determines the texture of baked goods.

The Dual Nature of Gluten

Gluten is not a single protein but a complex of two main protein fractions: gliadin and glutenin. These two components work in concert to create the unique viscoelastic properties that make wheat dough ideal for bread, pasta, and other baked goods. Together, they form a cohesive and continuous protein network when flour is hydrated and kneaded, trapping gas and providing structure.

Gliadin: The Viscous, Extensible Component

Gliadin is a component of gluten that contributes to the dough's viscosity and extensibility (ability to stretch). These proteins are generally monomeric and more compact than glutenins, which allows them to move freely within the dough.

Glutenin: The Elastic, Strong Component

Glutenin provides the elasticity and strength of dough. These are polymeric proteins, large aggregates linked by disulfide bonds, giving glutenin a more fibrous structure.

The Formation of the Gluten Network

When water is added to wheat flour, gliadin and glutenin hydrate. Kneading helps these proteins form a three-dimensional gluten network through covalent and non-covalent bonds. Key bonds include disulfide bonds, primarily linking glutenin polymers for stability and elasticity, and non-covalent hydrogen and hydrophobic bonds. For more details on the properties and formation of gluten, see {Link: Natuview https://www.natuview.jp/en/blogs/news/gliadin-vs-glutenin-gluten-effects-on-health}.

Gliadin vs. Glutenin: A Comparative Look


Feature	Gliadin	Glutenin
Function in Dough	Provides viscosity and extensibility (stretch).	Provides elasticity and strength.
Molecular Structure	Monomeric (single polypeptide chain), compact and spherical.	Polymeric (aggregated subunits), large and chain-like.
Disulfide Bonds	Primarily intramolecular (within the same protein).	Primarily intermolecular (linking different subunits together).
Solubility	Soluble in aqueous alcohols.	Insoluble in water, requires bond reduction for solubility.
Impact on Celiac Disease	Contains the highly immunogenic, digestion-resistant peptides that trigger the autoimmune response.	Considered less directly immunogenic but still part of the gluten complex.

The Role of Gluten in Baking and Health

The ratio of gliadin to glutenin influences the type of baked good. Hard wheat, used for bread, has more glutenin for strength, while soft wheat, for cakes, has more gliadin for tenderness. Gluten is generally harmless, but can cause issues for those with celiac disease, non-celiac gluten sensitivity, or wheat allergy. In celiac disease, gliadin triggers intestinal damage, requiring a strict gluten-free diet. To learn more about celiac disease, visit the National Institute of Diabetes and Digestive and Kidney Diseases website.

Conclusion

To answer, "what is the main protein in gluten?", it's a system of gliadin and glutenin. Neither is solely "the main one"; their interaction provides gluten's properties. Gliadin offers stretch and viscosity, glutenin strength and elasticity, crucial for many foods. Understanding these proteins is important for baking and managing gluten-related health.

Frequently Asked Questions

Neither gliadin nor glutenin is the sole main protein; rather, they are both equally essential components that interact to form the complex protein network known as gluten.

The primary function of gliadin is to provide the dough with viscosity and extensibility, giving it the ability to stretch and flow.

Glutenin provides the dough with elasticity and strength, allowing it to resist deformation and expand during fermentation.

When gliadin and glutenin are mixed with water and kneaded, they combine and link up to form a continuous, three-dimensional viscoelastic network called gluten.

While both are part of gluten, gliadin is the component most associated with triggering the autoimmune response in celiac disease due to specific peptide sequences that resist full digestion.

Disulfide bonds are crucial for the structure of the glutenin polymers, acting as strong covalent links between the protein subunits and contributing significantly to the dough's strength and elasticity.

Yes, the ratio of gliadin to glutenin significantly impacts baking quality. A higher glutenin content results in a stronger, chewier dough, while a higher gliadin content produces a softer, more extensible dough.