Question

Which protein fraction constitutes gluten?

• A. Prolamin and protease
• B. Gliadin and glutenin
• C. Gliadin and zein
• D. Prolamin and Gliadin

Hint:

Remember: Gliadin = Plasticity/Extensibility, while Glutenin = Elasticity/Tecity.
The balance between these two fractions determines the overall bread-making quality of wheat flour.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Gluten is a cohesive, viscoelastic protein network that forms when wheat flour is hydrated and kneaded.
It is responsible for the unique baking qualities of wheat dough, ebling it to retain gas during fermentation.

Step 2: Detailed Explation:
Wheat proteins can be categorized into non-gluten proteins (albumins and globulins) and gluten proteins.
The gluten proteins represent about \(80\%\) of the total protein in wheat.
This fraction is composed of two main storage proteins: gliadin and glutenin.
Gliadin is a monomeric protein (soluble in \(70\%\) aqueous ethanol) that provides extensibility and viscosity to the dough.
Glutenin is a polymeric protein complex linked by disulfide bonds (insoluble in alcohol but soluble in dilute acids or alkalis) that provides elasticity and strength.
The interaction between hydrated gliadin and glutenin forms the characteristic viscoelastic gluten matrix.
Other options, such as zein (found in corn) or protease (an enzyme), do not form wheat gluten.

Step 3: Fil Answer:
The correct option is (B).