Cereals processing technology

Asian noodle processing 139
White salted noodle flour requirements
Recently in China new specifications were established for the quality of flour
used in making noodles. First and second grade flour ash content should not
exceed 0.55 percent and 0.70 percent, wet gluten should not be less than 28 and
26 percent and farinograph stability not less than 4.0 and 3.0 min respectively. 30
They also indicated that the wheat used to prepare this flour must have a falling
number greater than 200 sec. The SDS sedimentation test which measures
protein quality has been found to be correlated significantly with the sensory
noodle textural attributes of firmness and chewiness. 15 Standards for Japanese
noodle flours are listed in Table 7.2.
7.3.3 White salted noodle processing
Production of Japanese WSN requires mixing for 10–15 min in horizontal
mixers, preferably vacuum mixers, Figs 7.3 and 7.4, although vertical mixers are
used occasionally. The salt concentration varies (2–3 percent) according to the
product and the time of year with less salt being preferred during the winter
months. 5 The mixing time required is a function of the quality of the flour,
concentration of water (28–45 percent) and salt, as well as the room temperature
and humidity.
The crumbs produced by mixing are divided and each portion passed through
separate sheeting rolls (180 mm diameter). The two sheets are then laminated/
combined by passing the two sheets through a larger diameter sheeting roll
(240 mm) at the initial noodle thickness to impart a large amount of work and
develop the gluten matrix, 5 see Fig. 7.5. It is not uncommon for the sheet coming
off these rolls to be collected on a spool and set aside for resting. The normal
resting period varies but is usually 30–60 min which results in improved
sheeting characteristics. The lamination process is often repeated just before the
start of the final sheeting process. 5 Gluten filaments align parallel to the sheeting
direction. Differences due to this alignment can be detected in noodle texture.
It has been announced recently that Nisshin Flour Milling has developed a
rolling system capable of producing three noodle layers, each from a different
dough, and then wafering them together in rollers to produce a triple layer effect.
This will allow production of a wide variety of noodle textures depending on the
nature of the doughs layered together. 31
Subsequent sheeting takes place on a series of rolls, with each reduction in
noodle thickness being limited to only 15–33 percent as dramatic changes in
noodle thickness can disrupt the established gluten network. 5 This increases the
number of sheetings and allows further development of the gluten. The size of
the reduction rolls declines from a diameter of 240 mm to 120 mm just before
cutting. The cutting rolls form two types of edges: a rounded versus the more
popular square cut noodle with the thickness being 75 percent of the noodle’s
width. Special cutting blades causing depression in the noodle can significantly
reduce the subsequent cooking time while retaining the desired textural
attributes (see Table 7.3). 5