What is Gliadin, one of the proteins in flour called?

November 12, 2025 •

3 min read

Over 70% of the total protein content in wheat flour is composed of storage proteins, the most significant of which are gliadin and glutenin. Specifically, gliadin is one of the proteins in flour called to interact with water and glutenin to create the stretchy, elastic network known as gluten.

Quick Summary

The protein gliadin is one of the two primary components that form the gluten network in flour when mixed with water. It is known for giving dough its extensibility and is essential for achieving the correct texture in baked goods.

Key Points

Gliadin is a Key Flour Protein: It is one of two primary storage proteins in wheat flour, alongside glutenin, that combine to create the gluten network.
Gliadin Adds Extensibility: This protein is responsible for giving dough its stretchiness and viscous properties, allowing it to expand without breaking.
Gluten Forms with Water: The formation of gluten, which provides structure and elasticity, is triggered when gliadin and glutenin are hydrated and mixed.
Control Over Texture: By manipulating factors like flour type, mixing time, and hydration, bakers can control the gluten development for different baking outcomes.
Health Considerations: Gliadin contains peptides that can trigger immune responses in individuals with celiac disease, necessitating a gluten-free diet for proper management.
Balance is Key: The ratio of gliadin to glutenin determines the balance of elasticity and extensibility, which is critical for the desired texture in baked goods.

Unpacking the Components of Flour Protein

Flour contains a complex mixture of proteins, but for baking purposes, the most crucial are the storage proteins. When we talk about "gluten-forming proteins," we are primarily referring to gliadin and glutenin. These two proteins exist separately within the dry flour but begin to form the viscoelastic gluten network as soon as water is introduced and mixing begins. Gliadin, along with its counterpart glutenin, is what gives dough its unique and versatile properties, allowing it to be stretched, kneaded, and to rise effectively during baking.

The Role of Gliadin and Glutenin

Understanding the individual functions of gliadin and glutenin is key to mastering baking science. While gliadin imparts extensibility and viscosity, glutenin is responsible for strength and elasticity. This means that gliadin allows the dough to stretch and spread out, while glutenin enables it to snap back into shape. The balance between these two components determines the final texture of the baked good, from a chewy loaf of bread to a flaky pastry.

The Gluten Network

When water is mixed with flour, the gliadin and glutenin molecules link together, and as the dough is kneaded, this network strengthens and organizes. This webbed structure is what traps the carbon dioxide gas produced by yeast or other leavening agents, causing the dough to rise. The strength of this network is critical for the finished product's crumb structure, texture, and volume. Different types of flour have varying ratios and quantities of these proteins, which explains why bread flour (higher protein) is suited for chewy loaves, while cake flour (lower protein) results in a more tender product.

Gluten Development and its Culinary Applications

The level of gluten development can be controlled by a baker to achieve different desired outcomes. For example, a rustic bread requires a strong, well-developed gluten network, often achieved with high-protein flour and extensive kneading. Conversely, a tender pie crust or cake requires minimal gluten formation, which is why recipes for these items often call for low-protein flour and a gentle mixing process.

To control gluten development, bakers can:

Choose the right flour: Use high-protein flour for breads and low-protein flour for cakes and pastries.
Control the mixing process: Kneading promotes gluten development, while minimal mixing limits it.
Adjust hydration: More water helps gliadin and glutenin link together, accelerating gluten formation.
Add fats and sugars: These ingredients can interfere with gluten formation, creating a more tender crumb.

Comparison of Gliadin and Glutenin


Feature	Gliadin	Glutenin
Function	Provides extensibility and viscosity	Provides elasticity and strength
Structure	Monomeric and globular	Polymeric and fibrous
Molecular Weight	Lower (e.g., 28,000–55,000 Da)	Higher, with long polymers (e.g., up to 10 million Da)
Interactions	Interacts with the glutenin network via non-covalent bonds	Forms the backbone of the gluten network through interchain disulfide bonds
Solubility	Soluble in aqueous alcohol	Insoluble in aqueous alcohol, can be solubilized after reduction

Potential Health Implications of Gliadin

For most people, gliadin and the gluten it forms are a normal part of a healthy diet. However, for individuals with celiac disease or non-celiac gluten sensitivity, the body can have an adverse reaction to gliadin peptides, leading to an inflammatory response. This can cause damage to the intestinal lining and a range of digestive symptoms. Awareness of the specific protein components like gliadin is crucial for those who must follow a strict gluten-free diet for medical reasons. Ongoing research into gluten and its components, such as that detailed by the National Institutes of Health, continues to advance our understanding of these health conditions.

Conclusion

Gliadin is a fundamental protein component of flour that plays a crucial role in forming the gluten network. Its unique properties of extensibility and viscosity work in concert with the elasticity of glutenin to give dough its structural integrity and texture. By understanding the science behind gliadin, bakers can better control gluten development to produce a wide range of perfectly textured baked goods. For those with gluten-related health conditions, recognizing gliadin as a key component of gluten is essential for navigating dietary needs and maintaining their health.

Frequently Asked Questions

Gliadin is specifically found in flours milled from certain grains like wheat, rye, and barley. It is not present in naturally gluten-free flours such as those made from rice, corn, or buckwheat.

Gliadin is one of the individual proteins found in dry flour. Gluten is the complex, interconnected protein network that forms when gliadin and another protein, glutenin, are combined with water and agitated.

Gliadin contributes extensibility and viscosity to dough, allowing it to be stretched. In combination with glutenin, it forms the elastic gluten network that traps gas, enabling baked goods like bread to rise.

No, true gluten-free products do not contain gliadin. For products to be labeled gluten-free, they must contain less than 20 parts per million of gluten, ensuring they are safe for people with celiac disease.

Gliadin contains peptides that are resistant to digestion and can trigger an immune response in genetically predisposed individuals with celiac disease. This leads to intestinal damage and a variety of associated symptoms.

No, a high gliadin content is desirable for baked goods that require a strong, elastic structure, like bread. For more tender and crumbly items such as cakes or pastries, a lower gliadin content is preferred.

Bakers manipulate gliadin content indirectly by choosing specific flours with higher or lower protein percentages. They also control mixing, hydration, and the addition of fats and sugars, which can inhibit or promote gluten formation.