2009_Book_FoodChemistry

4.4 Polysaccharides 317
Table 4.24. Shape, composition, and properties of different starch granules
Source Shape a Diameter Crystallinity Gelatinization Swelling Amylose Amylopectin
(µm) (%) temperature at 95 ◦ C b Percentage Polymeri- Iodine Polymeri-
( ◦ C)
(%) c sation binding sation
degree constant d degree e
Cereal
Wheat l,p 2–38 36 53–65 21 22–28 2100 0.21 19–20
Rye l 12–40 57–70 28 0.74 26
Barley l 2–5 56–62 22–29 1850 26
Corn p 5–25 62–70 24 28 940 0.91 25–26
Amylomaize 20–25 67–87 52–80 1300 0.11 23
Waxy corn p 39 63–72 64 0–1 20–22
Oats 5–15 56–62 27 1300 20
Rice p 3–8 38 61–78 19 14–32 0.59
Waxy rice 55–65 56 1
Millet p,s 4–12 }
69–75
g g
}22 g g
Sorghum p,s 4–24 21–34
Waxy sorghum 68–74 49
Legumes
Horsebean s,o 17–31 64–67 32–34 1800 1.03 23
Smooth pea n(si) 5–10 }
57–70 h
33–35 1300 1.66 26
Wrinkled pea n(c) 30–40 63–75 1100 0.91 27
Roots and tubers
Potato e 15–100 25 58–66 23 3200 0.58 24
Cassava semi-s,s 5–35 38 f 52–64 17 1.06
a l = lenticular, p = polyhedral, s = spherical, o = oval, n = kidney-shaped, el = elliptical, si = simple, c = compound.
b Weight of swollen starch, based on its dry weight; loss of soluble polysaccharides is considered.
c Based on the cum of amylose and amylopectin.
d mg iodine/100 mg starch.
e Cleavage degree of polymerization, determined by degradation of branches with pullulanase or isoamylase.
f
Tapioca.
g Millet.
h Pea.