1.2 Rice Noodles
Noodles are safe and nutritious product that
conforms to the set food standards of various
countries. With the increase in Asia pacific
economy, the demand for quality noodle products
among consumer gets higher [1]. Rice noodles are
the most consumed form of rice product next to
cooked rice grain in Asia [6]. Noodles may either
be served by frying and mixing with vegetables
and meats or served as a soup noodle by boiling
in a broth. Rice protein lack gluten; hence lack the
functionality of continuous visco-elastic dough.
Rice flour is therefore pre-gelatinized in order to
act as binder for the remaining flour. The extent of
pre-gelatinization plays a vital role in providing
desirable texture to the noodle strands. The level of
gelatinization is maintained adequately to develop
the desired binding power during the process of
extrusion; though too much gelatinization may
create handling problems [6]. Rice noodles are
commonly prepared by two main methods; sheeting
of dough to develop flat noodles and extruding to
develop vermicelli. The raw materials for rice based
noodles are usually evaluated by determining their
functionalities; processes involved and desired end
product [1].
Generally, rice noodles are made from flour
containing high amylose concentration (> 22%),
which contributes to the gel network. It provides
firm structure and desirable properties to noodle [5-
6]. There is significant association found between
amylose and acceptability of rice noodles [7]. The
wide variation in physical and chemical properties
of rice flour greatly influences the textural quality of
rice noodles. Additionally, rice noodles properties
are also influenced by paste viscosities, swelling
power (SP) and gel texture of rice starch. The high
amylose concentration in rice flour gives noodle
with bright color and low bulk density because of
their educed swelling power [8-10].The chemical
composition i.e. protein, fat, carbohydrate and ash
concentration of rice noodles were found to be
7.20%, 0.84%,91.7% and 0.24%, respectively [11].
The texture of rice noodles is less cohesive and
extensive due to the absence of gluten. The textural,
cooking and sensory properties depend upon the
pasting and physicochemical attributes of rice flour
obtained from different rice varieties [5, 9, 12].
Flour particle size can also influences the properties
of noodles [9, 13]. However, noodles made from
flour having smaller particle size showed better
textural properties [13]. Similarly, the smaller
particle size had highest water absorption index,
hot paste viscosity, peak viscosity, and breakdown,
final or cold paste viscosity and gel hardness, but the
lowest gelatinization temperature [5, 13]. However,
fat concentration did not significantly influence the
properties of noodles [5, 10, 13].
Rice vermicelli is prepared from flour having
high amylose concentration, which is obtained
by steeping followed by wet milling. The flour
is filtered, pulverized and molded into balls that
are pre-cooked in boiling water for 20 minutes or
steamed to facilitate surface gelatinization. The
partially cooked balls are kneaded, which causes
uniform distribution of the gelatinized starch all
over the dough which performs a binding role.
The dough is then passed through the extruder or
noodle making machine to make noodle strands.
The noodle strands are then put in boiling water and
taken out when cooked adequately. Immediately,
the cooked noodles are cooled by transferring
into a cold water container. The noodles are then
allowed to dry by placing them in racks. On the
other hands, the noodles can also be subjected
to steaming process for a time period of 10-15
minutes, by directly placing them in racks, followed
by tap water washing, and drying. Dry milling is
preferred to wet milling for making rice noodles
in Japan. The dry milled flour is mixed with water
and heated for about one minute at 100
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