What Type of Protein is in Wheat?

November 18, 2025 •

2 min read

Over 75% of the total protein found in a wheat grain is comprised of gluten, a complex network of storage proteins. These proteins are responsible for the unique viscoelastic properties of wheat dough and can trigger adverse health effects in certain individuals. Understanding the specific proteins in wheat is essential for bakers, food scientists, and those with gluten sensitivities.

Quick Summary

The main protein in wheat is gluten, composed of two primary protein groups: gliadins and glutenins. These proteins contribute to the unique elasticity and extensibility of dough, affecting baking quality. Gluten can also cause health problems, such as celiac disease and non-celiac gluten sensitivity, in susceptible people.

Key Points

Gluten is the main protein in wheat: It accounts for roughly 85% of total wheat protein content and is a complex mixture of gliadin and glutenin proteins.
Gliadins provide viscosity: These are monomeric, single-chain proteins that contribute to the extensibility and viscous flow of dough.
Glutenins provide elasticity: These are polymeric, multi-chain protein aggregates linked by disulfide bonds, responsible for the strength and elasticity of dough.
Non-gluten proteins also exist: Water-soluble albumins and salt-soluble globulins perform metabolic and protective functions within the grain.
Protein composition affects baking quality: The specific balance of gliadins and glutenins determines dough properties and end-product quality, such as bread or cake texture.
Gluten can cause health issues: Specific protein fractions, particularly gliadins, are known triggers for celiac disease and other gluten-related sensitivities.

The Gluten Complex: Gliadins and Glutenins

The protein content of wheat typically ranges from 7% to 22% of its dry weight, with about 85% being gluten proteins. Gluten is not a single protein but a complex of storage proteins, primarily gliadins and glutenins, which provide distinct properties to dough. When flour and water mix, these proteins interact to form the gluten network.

Gliadins: The Viscous Component

Gliadins are monomeric proteins soluble in aqueous alcohols and contain intramolecular disulfide bonds. They contribute to dough's viscous properties, allowing extension and flow. Different types of gliadins exist, classified by electrophoretic mobility. Some $\alpha/\beta$-gliadins and $\gamma$-gliadins contain epitopes linked to celiac disease, while $\omega$-gliadins are implicated in wheat-dependent exercise-induced anaphylaxis and baker's asthma.

Glutenins: The Elastic Component

Glutenins are polymeric proteins insoluble in aqueous alcohol, providing dough with elasticity and strength. Intermolecular disulfide bonds link these proteins, forming large aggregates. High-Molecular-Weight (HMW) glutenin subunits are crucial for dough strength and elasticity, while Low-Molecular-Weight (LMW) subunits also contribute to the gluten network structure.

The Non-Gluten Protein Fractions

Besides gluten, wheat contains other proteins classified by solubility using the Osborne method. Albumins are water-soluble and act as enzymes. Globulins are salt-soluble and also serve protective roles. Triticins are storage globulins distinct from the main gluten complex.

Comparison of Wheat Protein Fractions


Protein Fraction	Solubility Characteristic	Primary Function in Dough	Molecular Structure	Associated Health Concerns
Gliadins	Soluble in aqueous alcohol	Viscosity and extensibility	Monomeric polypeptide chains with intramolecular disulfide bonds	Celiac disease, wheat allergy
Glutenins	Insoluble in aqueous alcohol	Elasticity and strength	Polymeric aggregates linked by intermolecular disulfide bonds	Celiac disease (lesser extent)
Albumins	Water-soluble	Metabolic and enzymatic roles	Diverse, often globular	Wheat allergy, baker's asthma
Globulins	Salt-soluble	Metabolic and protective roles	Diverse, often globular	Wheat allergy

The Role of Wheat Protein in Food and Health

The balance of gliadins and glutenins makes wheat flour versatile for baking, allowing dough to trap gases and produce airy bread. This protein composition can be adjusted for different textures in various baked goods. However, some individuals face health challenges. Celiac disease is an autoimmune response to gluten, particularly gliadin fragments. Non-celiac gluten sensitivity causes similar symptoms without the same immune damage. Wheat allergy, a separate IgE-mediated response, can be triggered by various wheat proteins, including albumins, globulins, and specific gliadins.

Conclusion: A Complex and Important Protein

The primary protein in wheat is gluten, a complex of gliadin and glutenin proteins. These components provide wheat flour with its unique dough-making properties. Non-gluten proteins like albumins and globulins also serve metabolic roles. While crucial for food products, this complex protein structure can cause adverse reactions in some individuals. Understanding the types of protein in wheat is essential for food production and consumer health. For more detailed information, consult authoritative sources such as those found on the National Institutes of Health website.

Frequently Asked Questions

Gliadin and glutenin are the two main protein groups that form gluten. Gliadin is a monomeric protein that contributes to dough's viscosity and extensibility, while glutenin is a polymeric protein that provides elasticity and strength. They are distinguishable by their solubility in aqueous alcohol.

Wheat protein is not entirely gluten, but gluten is the major component, accounting for approximately 85% of the total protein. The remaining proteins consist of albumins and globulins.

The elasticity of wheat dough is primarily caused by the glutenin proteins. These proteins form large, polymeric networks linked by intermolecular disulfide bonds, which gives the dough its unique elastic properties.

People can be sensitive to wheat protein for several reasons. In celiac disease, the immune system reacts to specific gliadin fragments. In wheat allergy, an IgE-mediated response is triggered by various wheat proteins. Non-celiac gluten sensitivity is another condition where gluten causes symptoms without the autoimmune or allergic reaction.

Gluten-free flour, by definition, does not contain wheat protein (gluten). It is made from alternative grains or starches like rice, maize, or potato, ensuring it is safe for individuals with celiac disease or gluten sensitivity.

Bakers use their knowledge of wheat protein to select the correct type of flour for their desired end product. High-protein flours, rich in gluten-forming proteins, are used for chewy bread, while low-protein flours are preferred for delicate cakes and pastries.

The Osborne classification categorizes wheat proteins based on their solubility. The main groups are albumins (water-soluble), globulins (salt-soluble), gliadins (alcohol-soluble), and glutenins (soluble in dilute acid/alkali after reduction).