Rice Noodles: Materials, Processing and Quality Evaluation
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was found that the texture of the gel depends on
rice variety, hydrocolloids and its concentration.
Addition of 0.2% (w/w) carraggnan to the Indica
rice starch improved the texture of rice gel. While,
addition of 0.3% (w/w) gellan to the Indica rice
starch enhanced the adhesiveness/ hardness ratio.
Likewise, pasting is an important functional
property, which occurs after gelatinization in starch
dissolution. It is an important index for evaluating
the starch properties of rice [39]. It consists of
swelling of starch granules, leaching of molecular
components from granules and finally total rupture
of granules. Several parameters can be acquired
from the pasting curve, which manifest the extent
of disintegration and beginning of retrogradation
[41]. However, starches obtained from tubers and
roots showed weak intra-granular bonding, lower
gelatinization temperature, rapid and uniform
granular swelling, paste clarity and high viscosity
compared to cereal starches [41]. The peak viscosity
(PV), trough (T), break down (BD), final viscosity
(FV), set back (SB) and pasting temperature of rice
flour were 253.17, 191.29, 61.88, 351.38, 160.08
RVU and 76.38 °C, respectively [9].The pasting
properties of rice flour from aged (paddy and milled)
rice and fresh rice from two rice varieties stored
at different temperature conditions for a storage
period of 10 months is shown in table 1. The SB
and FV values were increased with the increase of
storage temperature and time. Moreover, the rise in
SB values showed a higher degree of retrogradation
due to the increase in rice firmness [42]. The rice
flour obtained from milled rice and stored paddy
was firmer compared to flour procured from fresh
rice; hence stored rice gave less sticky texture
[39]. Ageing of rice and amylose concentration
significantly influenced the pasting properties of
rice [43]. Kanlayakritand Maweang [44] studied
the pasting properties of rice flour obtained from
stored paddy and freshly milled rice under different
Table 1. Comparison of pasting properties of rice flour from fresh rice and aged (paddy and milled) rice
from two rice varieties stored at cold room, room temperature and warehouse for 10 months [44].
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