Explain starch gelatinization, Biology

Assignment Help:

Starch gelatinization

Undamaged starch granules are insoluble in cold water but can imbibe water  reversibly i.e. they can swell slightly and then return to their original size on drying, when starch is heated with excess of water, the molecular order of the granule is gradually and irreversibly destroyed at the gelatinisation temperature, which is approximately in the  range of 60-70°C for most of the starches. Amylose is preferentially leached out of the network and gets solubilized, however, some leaching of amylose can also occur prior to gelatinization. When further heated, starch granules are disrupted and partial solubilization is achieved. Total gelatinization usually occurs over a temperature range with larger granules generally gelatinizing first. At temperatures below 100° C, true molecular solution is not achieved and the swollen hydrated granules consisting of mainly amylopectin remain.  Continued heating of starch granules in excess water results in further granule swelling, additional leaching of soluble components (primarily amylose) and eventually, total disruption of granules especially with the application of shear forces,. This phenomenon results in the formation of a starch paste. The melting temperature of the crystallites is 190°C. Gelatinization is an endothermic process (10 mJ/mg), i.e. a chemical reaction accompanied by the absorption of heat.   

 


Related Discussions:- Explain starch gelatinization

Whta are radial loops , When the chromosomes  are depleted  of histo...

When the chromosomes  are depleted  of histones  they  are seem  to have  a central fibrous 'protein  scaffold'  or nuclear  matrix  to which the DNA is attached  in loops. Therefo

Heterospermy, What is heterospermy?also give its significance?

What is heterospermy?also give its significance?

Primary production - ecosystem, Primary Production - Ecosystem Energy ...

Primary Production - Ecosystem Energy accumulated by plants during photosynthesis is called production or more specifically primary production. It is the first and the basic f

What is the Evolution of migration, Evolution of migration Eg Be...

Evolution of migration Eg Benefits associated with migratory flights must be greater than those associated with staying in Alaska and having to tolerate seasonal changes

Earthquake energy, Large Quantity of energy is released during an earthquak...

Large Quantity of energy is released during an earthquake with a combination of radiated elastic strain seismic waves frictional, heating of the fault surface and cracking of the r

How to repair the defects in post myocardial , How to repair the defects in...

How to repair the defects in post myocardial ? Repair of Defect :  The approach to the defect is through ventriculotomy over the infarcted area. The defect is repaired

What is nerve impulses in human biology, What is Nerve Impulses in human bi...

What is Nerve Impulses in human biology? A nerve impulse is an electrical signal carried by a nerve cell. Unlike electrical transmission in wires, this impulse is non-decremen

Coa to succinate in the citric acid cycle, Name the high-energy complex gen...

Name the high-energy complex generated during the conversion of succinyl CoA to succinate in the citric acid cycle GTP  or  ATP is  the high-energy  complex generated during th

What are fibroids, Fibroids, also called as leiomyomas, are benign smooth m...

Fibroids, also called as leiomyomas, are benign smooth muscle tumors that happen in the uterus. They grow under the influence of estrogen and progesterone, and are therefore seen i

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