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

How are grasslands classified, How are grasslands classified? Grasslan...

How are grasslands classified? Grasslands might be classified into steppes and savannahs. In the steppes the prevailing vegetation is grass, as in the pampas of South America

Name some drugs to prvent tuberculosis, Name some Drugs to prvent tuberculo...

Name some Drugs to prvent tuberculosis Pyrazinamide can cause morbilliform rash, arthralgias and asymptomatic hyperuricemia, and blocks the hypouricemic action of allopurinol (

Principles of darwinism, PRINCIPLES OF DARWINISM - 1 .       OVERPROD...

PRINCIPLES OF DARWINISM - 1 .       OVERPRODUCTION (PRODIGALITY) - All organisms have enormous fertility and they multiply in geometric ratio. Examples of over product

Determine the enzymatic analysis in foods, Enzymatic analysis in foods: app...

Enzymatic analysis in foods: applications in food industry Did you know that the degree of bacterial contamination of foods or freshness of food, particularly, meat etc. can be

Major metabolic gases transported by the blood, Q. Which are the two major ...

Q. Which are the two major metabolic gases transported by the blood? The major metabolic gases transported by the blood are molecular carbon dioxide (CO 2 ) and oxygen (O 2 ).

How sugar is used in bakery application, How Sugar is used in Bakery Applic...

How Sugar is used in Bakery Application? In bakery applications, sugars are used to impart flavor, aroma and color. During the mixing process, excess gluten development can mak

Explain some characteristic features of mucor, Explain some Characteristic ...

Explain some Characteristic Features of Mucor? 1. Stolons characteristics of Rhizopus are absent in Mucor. The aerial mycelium in Mucor consists of branched hyphae, which grow

Why rna was the first genetic material, Why does scientist think that RNA w...

Why does scientist think that RNA was the first genetic material?

Describe in brief about the boron - micronutrients, Describe in brief abou...

Describe in brief about the Boron  - Micronutrients  Boron is required in extremely small amounts in the range of 0.01 to 1.0 ppm. The actual amount may vary from crop to crop

., what is the skeleton in the different classes of coelentrata known

what is the skeleton in the different classes of coelentrata known

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