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

Cells, What surrounds a plant cell

What surrounds a plant cell

Explain the nasopalatine nerve and vessels, Nasopalatine nerve and vessels ...

Nasopalatine nerve and vessels Found in the nasopalatine canal, must be taken care off when placing implants in the maxillary incisor region. Subperiosteal implant placement o

Disease occurrence due to climate change in animals, Disease occurrence due...

Disease occurrence due to climate change The movement of animal diseases across physical and political boundaries threatens food security and creates a global public co

Respiration, different type of respiration in animals

different type of respiration in animals

Guess the number of different haploid cells, A diploid cell contains four p...

A diploid cell contains four pairs of homologous chromosomes designated C1 and C2, M1 and M2, S1 and S2, and W1 and W2. Predict the number of different haploid cells that could be

Phylum:Echinodermata , What classifies an animal into the Echinodermata phy...

What classifies an animal into the Echinodermata phylum?

Why male and female gametophytes are independent, Male and female gametophy...

Male and female gametophytes are independent and free-living in: 1. Mustard 2. Castor 3. Pinus 4. Sphagnum Sphagnum

Carbohydrates, Carbohydrates are the next important nutrients as they have ...

Carbohydrates are the next important nutrients as they have to perform a variety of functions such as: 1) Provide major source of energy 2) Breakdown of fatty acids and preve

What is peri-implantitis, Peri-Implantitis (Infective Process- Bacterial Or...

Peri-Implantitis (Infective Process- Bacterial Origin) Bacterial invasion of the peri-implant soft tissue results in its inflammation followed by rapid bone loss. Peri-Implanti

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