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

Water - properties and functions, W A TER Occurence Water is ...

W A TER Occurence Water is the most abundant substance, covering 70% of earth's surface. It constitutes 60-90% of living cells.              5-6% in tooth e

Microorganisms on on basis of nutrient degradation capacity, Q. Microorgani...

Q. Microorganisms on On basis of nutrient degradation capacity? On basis of nutrient degradation capacity: - Proteolytic: Microorganisms, which are capable of protein degra

Cu ions released from copper, Cu ions released from copper - releasing Intr...

Cu ions released from copper - releasing Intra Uterine Devices (IUDs): 1. make uterus unsuitable for implantation 2. increase phagocytosis of sperms 3. suppress sperm moti

Physical concepts of plant water relation - diffusion, Physical Concepts of...

Physical Concepts of Plant Water Relation - Diffusion Diffusion is a spontaneous process that leads to net movement of a substance from a region of higher concentration to a r

Explain about myocardial infarction, Q. Explain about Myocardial Infarction...

Q. Explain about Myocardial Infarction? It is an initial acute phase of cardiovascular disease caused by the blockage of a coronary artery supplying blood to the. Heart shows t

How do birds reproduce, Q. How do birds reproduce? Birds like every ver...

Q. How do birds reproduce? Birds like every vertebrate have sexual reproduction. Their embryos develop within shelled eggs containing extraembryonic membranes and exterior the

Define maxillofacial prosthodontics, Q. Define Maxillofacial Prosthodontics...

Q. Define Maxillofacial Prosthodontics? Dental implants are now been increasingly used for Maxillofacial Prosthodontics. Maxillofacial Prosthodontics involves the prosthetic re

Define about the spectroscopy- colorimetry, Define about the Spectroscopy- ...

Define about the Spectroscopy- colorimetry? Spectroscopy, therefore, is the study of the absorption and emission of radiation by matter. Absorption Spectroscopy is usually used

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