The paste/gel characteristics of the starch were determined
using a dynamic rheological test, as described by Tran et al. (2013).
The starch paste samples (5% starch content) heated in a boiling
water bath for 30 min with stirring were loaded into a rheometer
between parallel 40-mm diameter plates at a gap distance of 1 mm.
After trimming off the overloaded portion of sample around the
plates, a thin layer of silicon oil was applied to the open side of the
sample to prevent moisture loss. A solvent trap was also used to
minimize water loss during the measurements. All the measurements
were conducted at 1% strain, which was within the linear
viscoelastic region (data not shown). A time sweep test was conducted
at a fixed frequency of 1 Hz by recording the storage (G
) and
loss (G
00
) moduli continuously at 4
C as a function of time over 2 h.
At the end of the gelation period, frequency sweep tests were
performed over the range of 0.1e10 Hz.
The pasting properties of the native and partially gelatinized
JFSS were investigated using a Rapid Visco Analyzer (RVA 3D,
Newport Scientific, Warriewood NSW, Australia). Samples of starch
(3 g, 11.2% moisture content) were dispersed in 25 g distilled water
in an aluminum canister. The starch slurry was initially mixed and
then held at 50 C for 2 min, heated to 95 C at 12 C/min, held at
95 C for 2 min 30 s, cooled to 50 C, and finally held at 50 C for
2 min at 160 rpm. The parameters analyzed were pasting temperature,
peak viscosity, final viscosity, breakdown viscosity, and setback viscosity.
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