Explain changes in gluten proteins during dough formation, Biology

Assignment Help:

Changes  In Gluten Proteins During Dough Formation

Initially, gluten is formed when flour and water are mixed together. The proteins in the flour, glutenin and gliadin cross  link, using water as a vehicle to form gluten. Enhancing this gluten structure  is important relative to developing a gas retaining structure in the chapati/bread.   When the hydrated bread flour is mixed and kneaded, the gluten proteins orient themselves aligns and partially unfolded. This enhances hydrophobic interaction and formation of disulphide bridges through -S-S- interchange reactions.  A  3-dimensional viscoelastic protein network is established, as the initial gluten particles transform into this membrane (film), thus serving to entrap starch  granules and other flour components.  Cleavage  of disulphide bridges by reducing agents such as cysteine,  destroys the cohesive structure of hydrated gluten and  bread dough ;  the addition of  agents  such  as  bromates,  increase  toughness    and elasticity. "Strong" flours from certain wheat varieties require long mixing time and give very cohesive dough. "Weak flours"  are less effective and  gluten network breaks down when the energy  or duration of mixing exceeds a certain level, probably because of -S-S-  bonds  are ruptured (especially in absence of  air). 

Dough strength  appears  to  be  related to a  large   content  of  high molecular   weight glutenins including totally insoluble  "residue proteins". From experiments with "reconstituted" wheat flours  of varying  gliadin and glutenin  ratios, it can be  postulated  that the  glutenins are responsible for the  elasticity,  cohesiveness and  mixing  tolerance  of  dough  whereas  gliadins   facilitate fluidity,   extensibility  and  expansion  of  the  dough, thus contributing  to a larger bread loaf volume. A proper balance of the proteins is essential for bread making.  Excessive  cohesion (glutenins)  inhibit \the expansion of trapped CO2 bubbles  during fermentation,  the rise of the dough and the subsequent  presence of  open  air cells in the bread  crumb.  Excessive extensibility (gliadins) results in gluten films that are weak and permeable; thus retention of CO2 is poor and dough collapse may occur.

 


Related Discussions:- Explain changes in gluten proteins during dough formation

Explain tetralogy of fallot repair and transposition, Explain Tetralogy of ...

Explain Tetralogy of fallot repair and Transposition of arteries? Tetralogy of Fallot Repair: This involves RV outflow resection, closure of the VSD and enlargement of the RV

Name the endocytosis, Name the endocytosis?   A.  During endocytosis of...

Name the endocytosis?   A.  During endocytosis of GLUT4 transporters in fat cells, there is removal of GLUT4 transporters from plasma membranes.   B.  During endocytosis of

Determine the foos sources of cyanocobalamin, Determine the Foos Sources of...

Determine the Foos Sources of cyanocobalamin? Vitamin B I2 is unique among vitamins in the sense that it is mostly found in foods of animal origin but is not generally present

Biological functions in which chlorine ions participate, What are the main ...

What are the main biological functions in which chlorine ions participate? Like sodium cations, chlorine anions actively participate in the regulation of the osmolarity of tiss

Define clinical assessment for vitamin a, Define Clinical Assessment For Vi...

Define Clinical Assessment For Vitamin A? Clinical features of deficiency occur as ocular and extra ocular lesions. Ocular lesions affect the posterior segment of the eye init

What is the difference between anabolism and catabolism, What is the differ...

What is the difference between anabolism and catabolism? Metabolism comprises two opposing processes: anabolism and catabolism. Anabolism is a set of synthesis reactions that t

Under which form is nitrogen fixed by living beings, Under which form is ni...

Under which form is nitrogen fixed by living beings? Most living beings cannot use molecular nitrogen to get nitrogen atoms. Producers fix nitrogen mostly from nitrate (NO3-).

Why it is important to study about soil, Why does one need to study about s...

Why does one need to study about soil and what is  its importance? You would be aware that, from the dawn of agriculture, cultivators were attracted to fertile soils of river

Diet-peri operative problems, Diet :  Pre-operatively, patients are on low...

Diet :  Pre-operatively, patients are on low calorie, low fat diet. However in the immediate post-operative period, strict dieting is not advisable. They need good nutrition for p

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd