THESIS

1.2.3 Degree of syneresis
Degree of syneresis in the samples, debranched for specific times,
was determined according to Karim et al. (2000) with modification. Portions of each
debranched starch paste were transferred into each disposable dish and covered with
adhesive tape to prevent moisture loss. The samples were frozen at -10°C for 16-hr
and thawed at 30°C for 2-hr. The samples were then subjected to a vacuum filtration
after freeze-thaw cycles. Water of syneresis from triplicate gel samples was collected
and weighed. The weight of retrograded gel and water syneresis was used to
calculated degree of syneresis as follows:
Degree of syneresis (%) = Weight of water syneresis × 100
Weight of retrogradation gel
1.2.4 Color value and water activity
The Hunter L*, a*, b* values of RS III samples were measured
using a Colorimeter (JS 555, Japan). Water activity (aw) was determined by Aqualab
Water Activity Meter (Series 3) at 25 o C (Pullman, USA).
1.2.5 Production yield
The weight of native rice starch and RS III samples were used to
calculated production yield of resistant starch type III formation. Production yield (%)
of the RS III was determined by using the formula:
Production yield (%) = Wt. of resistant starch × 100
Wt. of rice starch
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