At least forty different components may be identified in a single wheat variety. Gluten’s other main protein fraction is glutenin.
Glutenin are protein polymers consisting of high and low molecular weight glutenin subunits HMW-GS and LMW-GS linked though disulphide bonds.
The polymeric glutenin protein have molecular sizes ranging up into the tens of millions of Daltons. The great length of these chains is presumed to confer in wheat its unique dough forming properties.
Glutenin is thought to provide most of the strength also called tenacity, to gluten, while gliadin provides its stretchiness or extensibility. Glutenin also provides elasticity to gluten; that is its ability to bounce back one it is stretched or pressed.
The network of glutenin and gliadin is formed when the long glutenin molecules cross link with hooks on the globular gliadin molecules.
This network is very stretchy and liable, and it appears that the combination of gliadin and glutenin responsible for gas retention in wheat four dough.
The stretchiness lets the dough structure hold on the gas of carbon dioxide, which is produced by yeast or baking powder and form the crumb or texture of the bread.
In cases of gluten intolerance, the gliadin fraction is the cause of the symptoms; the glutenin fraction is not.
Glutenin in flour
