Cereals processing technology

Asian noodle processing 149
with the necessary ingredients dissolved in the water. Salt has the effect of
decreasing farinograph absorption; however, in the presence of alkali, its impact
is masked by the alkali’s dominant strengthening effects.
A two-stage mixing regime involving a short initial high speed mix followed
by a longer slow mix is used. The amount of mixing time is a function of the
quality of the noodle being prepared. Common noodles have a much shorter
mixing time due to a reduction in the slow mix phase. The use of vacuum mixing
in Japan, in conjunction with correct mixing moisture, 36–40 percent, can
produce a higher quality noodle as it allows for greater water addition. The
addition of extra water in this manner allows the flour starch to gelatinize and
swell more than a reduced water content noodle during the steam processing
stage. This will reduce the consumer’s subsequent cooking time, a highly
desirable trait, as well as limiting the loss of cooking solids to the broth. The
additional water added during mixing also allows for better development of a
gluten matrix ensuring improved noodle texture during steeping and a better
overall appearance. 23 A uniform gluten matrix is essential for a high-quality
product. 42
Instant noodles get their unique waved shape due to either the use of diverter
flaps just behind the cutting blades or by a reciprocating conveyor belt. The
wave structure allows for more efficient steaming and subsequent frying as the
noodle strands are separated. It is important for the developed gluten, which
becomes a permanent structure at a lower temperature than starch, to be set
before the subsequent starch swelling.
The cut noodles can be steamed for varying lengths of time, 100–240 sec
based on the noodles’ quality. 41 The steamed noodles are then passed on a
conveyor belt under a series of cooling fans to rapidly reduce their temperature.
The noodles are then placed in single serving molds on a weight basis before
being conveyed to a frying chamber.
Palm oil, or a mix with beef tallow is common throughout most South East
Asian countries although Korea uses mainly palm oil. The average Korean
instant fried noodle has 16.7 percent lipid comprised of C16:0, C18:1 and C18:2.
The ratio of saturated to mono-unsaturated to polyunsaturated is 1.0:0.77:0.19. 43
Frying conditions and length of time are a function of the quality of the noodle
being made. It is normal in Korea to maintain the temperature at the end of the
chamber at a slightly higher temperature than the inlet. 44 Antioxidants such as
tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA) and -
tocopherol can be added to the frying oil to retard rancidity although in many
countries the oil is used well past its best condition. Addition of either TBHQ or
BHA to the oil at 200 ppm increases the noodle shelf-life twofold. A
combination of TBHQ (200 ppm) and disodium ethylene diamine tetraacetate
(EDTA) extends the noodle shelf-life fivefold over antioxidant free frying. Even
coating the inner packaging surface with TBHQ (200 ppm) doubles the
product’s shelf-life. 45
The frying (1–2 min) in high temperature oil, 140–150ºC, causes the
immediate conversion of the noodle’s water to steam resulting in a spongy