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Starch: 5 March 2017

This document provides information on starch terminology and the characteristics of different types of starch. It discusses the molecules that make up starch granules - amylose and amylopectin. Amylose is a linear molecule while amylopectin is highly branched. It then covers the amylose and amylopectin content of various food starches like corn, wheat, rice and potato. The document also looks at the size, shape, gelatinization properties, lipid and protein content, and film forming ability of these common food starches.

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syifa latifa zahida
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71 views12 pages

Starch: 5 March 2017

This document provides information on starch terminology and the characteristics of different types of starch. It discusses the molecules that make up starch granules - amylose and amylopectin. Amylose is a linear molecule while amylopectin is highly branched. It then covers the amylose and amylopectin content of various food starches like corn, wheat, rice and potato. The document also looks at the size, shape, gelatinization properties, lipid and protein content, and film forming ability of these common food starches.

Uploaded by

syifa latifa zahida
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
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Download as PDF, TXT or read online on Scribd
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STARCH

5 March 2017
STARCH TERMINOLOGY
Amylose
• Long, chain-like molecule of polymerized dextrose molecule
• Smallest fraction in grain starch granules
• It is helical in form

Amylopectin
• Larger, highly branched molecule of polymerized dextrose chain
• Largest and most prevalent molecule in starch
• Due to its size and branched form, it is the most viscous molecule

Granule
• The more crystalline structure of molecule of amylose and amylopectin
molecules bound together into semi-spherical shapes

DP
• Short of Degree of polymerization, referring to the number of molecules
linked together
MOLECULE STRUCTUR OF STARCH
Amylose

Amylopectin
CHARACTERISTIC OF AMYLOSE &
AMYLOPECTIN

Characteristic Amylose Amylopectin


Shape Essentially linear Branched
Linkage α-1,4 (some α-1,6) α-1,4 and α-1,6
Molecular weight Typically <0.5 million 50-500 million
Films Strong Weak
Gel formation Firm Non-gelling to soft
Color with iodine Blue Reddish brown
APPROXIMATE AMYLOSE & AMYLOPECTIN
CONTENT OF COMMON FOOD STARCHES

Starch type Amylose content (%) Amylopectin content (%)


Dent corn 25 75
Waxy corn <1 >99
Tapioca 17 83
Potato 20 80
High-amylose corn 55-70 (or higher) 45 – 30 (or lower)
Wheat 25 75
Rice 19 81
APPROXIMATE SIZE AND SHAPE OF
COMMON FOOD STARCH GRANULES

Property Dent Waxy High- Wheat Rice Potato Tapioca


corn corn Amylose
corn
Source Cereal Cereal Cereal Cereal Cereal Tuber Root
Diameter 5 - 30 5 - 30 5 - 30 1 - 45 1-3 5 - 100 4 - 35
(µm)
Shape Polygonal, Polygonal, Polygonal, Round, Polygonal, Oval, Oval,
round round round, lenticular spherical spherical truncated,
irregular compound ”kettle
granules drum”
SHAPE OF COMMON SATRCH
APPROXIMATE LIPID AND PROTEIN
CONTENT OF COMMON STARCHES

Composition Dent corn Waxy corn Wheat Potato Tapioca


(% ds)
Protein 0.35 0.35 0.4 0.1 0.1
Lipid 0.80 0.80 0.9 0.1 0.1
Ash 0.1 0.1 0.2 0.08 0.1
Phosphorus 0.02 0.02 0.06 0.08 0.01
GELATINIZATION CHARACTERISTICS
Parameter Dent corn Waxy corn Wheat Potato Tapioca
Average peak 600 800 300 3000 1000
viscosity (BU,
5%)
Paste viscosity Medium High Low High High
Paste 75 - 80 65 - 70 65 - 70 60 - 65 60 -65
temperature oC
Paste texture Short, heavy Long, stringy, Short, heavy Long, stringy, Long,
body fluid body body fluid body stringy, fluid
body
Pate clarity Opaque Translucent Opaque Translucent Translucent
Retrogradation High Very low High Medium Low
STARCH FILM
Parameter Dent corn Waxy corn Wheat Potato Tapioca
Clarity & Gloss Low High Low High High
Film strength Low High Low High High
Flexibility Low High Low High High
Film solubility Low High Low High High
PASTING PROFILE
(BU, 9.21% (W/W))
THANK YOU

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