Cooking Breakfast Cereals
All cereals contain a large proportion of starch. In its natural form, the
starch is insoluble, tasteless, and unsuited for human consumption. To
make it digestible and acceptable it must be cooked.
Breakfast cereals are products that are consumed after cooking, and they
fall into two categories: those made by a process that does not include
cooking and which therefore have to be cooked domestically (hot
cereals) and those which are cooked during processing and which
require no domestic cooking.
The first class of products is exemplified by various types of porridge,
the second by products which are described as 'ready to-eat' cereals.
Besides the distinction regarding the need for domestic cooking as
against readiness for consumption, breakfast cereals can also be
classified according to the form of the product, and according to the
particular cereal used as the raw material.
Flaked products from maize
Corn flake process flow chart
Maize
Cleaning
Cooking
In the traditional batch process for making
cornflakes, a blend of maize grits - chunks of
about 0.5-0.33 of a kernel in size - plus
flavoring materials, e.g. 6% (on grits wt) of sugar,
2% of malt syrup, 2% of salt, possibly plus heat-
stable vitamins and minerals, is pressure-cooked
for about 2 h in rotatable batch cookers at a steam
pressure of about 18 psi to a moisture content of
about 28% after cooking.
Drying
The cooking is complete when the color of the grits has
changed from chalky-white to light golden brown; the grits
have become soft and translucent, and no raw starch remains.
The cooked grits are dried by falling against a counter-
current of air at about 65°C under controlled humidity
conditions, to ensure uniform drying, Moisture content of
about 20%, a process taking 2.5-3 h., and are then cooled
rested to allow equilibration of moisture.
Resting/ cooling
The resting period was formerly about 24 h, but is
considerably less under controlled humidity drying
conditions.
Flaking
The dried grits are then flaked on counter-rotating rollers,
which have a surface temperature of 43°-46°C, at a pressure
of 40 t at the point of contact.
Rolling and Toasting
The flakes thus formed are toasted in tunnel or travelling
ovens at 300°C for about 50 sec.
The desirable blistering of the surface of the flakes is related
to the roller surface temperature and to the moisture content
of the grits, which should be 10-14% m. c. when rolled.
Cooling
Sprayed with solutions of vitamins and minerals
After cooling, the flakes may be sprayed with solutions
of vitamins and minerals before packaging.
Packaging
CHIURA (BEATEN RICE FLAKES)
Chiura or beaten rice flakes is a very common food item in Nepal. It is
pre-cooked, has a crispy texture, and is in a ready-to-serve form. It is
eaten as a snack or as full meal with achar (pickle), chutney, meat, eggs,
vegetables, beans, etc. It is also found in other Southeast Asian countries
such as India, Bangladesh, Bhutan and Pakistan. It is popular in all
communities especially in Newar, Brahmin, Chettri, Rajbanshi,
Choudhari, etc. Special, coarse varieties of rice are suitable for chiura
production. Chiura is considered an essential item in occasions like
marriage ceremony, festivals, picnic and party. Researches show that
chiura making incurs loss of minerals like calcium and iron. To this end,
there have been some studies on the fortification of chiura with these
minerals for compensating the loss.
Processing
The traditional method of chiura preparation does not have much
variation. The preparation utilizes simple tools like okhli1 and dhiki2.
However, the use of power- operated mills is gaining popularity,
especially for large scale production. As a result, people prefer buying
chiura from the stores rather than preparing themselves using traditional
okhli and dhiki. But chiura from traditional method tastes better than
that from mill. The traditional procedure for chiura preparation in Nepal
is presented in Fig. 1.1.
Recently in the Terai, chiura is prepared using power mill in large-scale.
Cleaned paddy is packed in jute bags and soaked in water-filled
cemented tanks for 1 to 2 days. The paddy is taken out and roasted in
karahi3 (Fig. 3.7) using large spoons for uniform stirring. It is then
passed via magnetic sieves to remove metal particles that may damage
machinery. While still hot the roasted paddy is passed between iron rolls
for flattening. The pulverized dust in chiura is removed mechanically by
an aspirator (fans). Chiura is packed in polythene-lined bags and sent to
market or store. Generally, chiura is consumed within 1 to 2 months of
production (depending on temperature, humidity, and packaging
factors).
Process Notes
Paddy ° Select a suitable variety and clean
Clean ° Remove dust and stone particles
1
A large-size wooden mortar and pestle
2
Foot-operated pounding tool
3
Caldron made of cast iron. It is generally used for preparing curry
Steep ° Soak paddy for 12-24 hrs depending upon
(soak) temperature; hot water soaking is faster
Cook ° Continue cooking until few grains burst
(steam)
Drain
Roast ° Roast paddy in small lots in a karahi or
earthenware pot until few grains begin to pop
Flake° Flatten immediately after roasting in an okhli
or in a dhiki (Fig. 1.2 and 1.3.)
° Continue beating until the paddy is dehusked
and flattened
Winnow ° Take out and remove pulverized husks and
dusts using nanglo4 (Fig. 1.4)
Chiura ° Ready to eat crispy rice flakes
Fig. 1.1 Preparation of chiura by traditional method
P e s tle
W o o d e n m o rta r
Fig. 1.2 Beating chiura in okhli
4
A circular winnowing tray made from bamboo strips
G r a in
B ro o m
Fig. Beating chiura in dhiki
BHUJA OR MURAI
Bhuja is a puffed rice product. It is mainly consumed as snack in the
Terai belt of Nepal. The word murai is derived from the term murra,
which means ‘puffed’. The nutritional value is similar to that of rice. It is
mainly used by the Tharu and Chaudhari ethnic groups of Nepal. For
them it is a very important food item in marriage ceremony, festivals and
other occasions. Murai is also used for the preparation of chatpate, a
peppery snack sold by the vendors in the local markets. The food goes
well with all types of dishes. It is generally produced from long variety
rice Oryzae indica.
Processing
Bhuja preparation requires different tools/equipment, such as metal pot,
drying mat, winnowing device, plastic bags, sand, wooden stirrer, plastic
bags, stove or fire wood, strainer, etc. A detailed method of bhuja
production by traditional method is given in Fig. 1.6.
The commercial method of bhuja production is different from the
traditional method. An outline of the commercial method is given.
Preparation of bhuja/murai by traditional method
Process
Paddy
Cleaning
Soaking ° 24 hrs in clay pot
Boiling ° In metallic pot over firewood or stove
Straining ° Draining of excess water
Cooling ° 12 hrs
Steaming ° Until a few grains begin to split
Drying ° Uniform drying on mat or floor
Hulling ° In a huller to remove hulls
Winnowi ° Separation of hulls in a winnowing device
ng
Seasoning ° Mix water and salt (~1%). Cook under uniform and
mild heating with continuous stirring
Puffing ° Baking in hot sand placed in sieve
Separatio ° Separation of puffed rice from the sand
n
Bhuja/Mu
rai
Packing ° In plastic bags and sealed with a sealer
Process
Preparation of
bhuja/murai by
modern method
Paddy
Cleaning ° Separation of foreign materials (impurities,
stones, etc.)
Grading ° Generally not done in traditional method
Soaking ° Done in soaking vats. Low temperature
soaking takes longer time. Longer soaking
produces better quality of murai. This
transfers the color of husk to bran and murai
becomes more attractive (reddish). Soaking
period depends on temperature. The
moisture content reaches 35-40%.
Drying ° Sun drying takes a long time and is labor-
intensive. Mechanical drying is faster
Tempering ° To equilibrate moisture to 12-13%
Dehusking ° A pair of rubber roller is used
Stone separation ° Not necessary if de stoning of paddy has
been done
Soaking in salt ° 1% salt (in the form of saturated brine)
solution ° For every 100kg rice, 4 lit of saturated brine
and 8 lit of plain water is used and mixed
thoroughly. The moisture reaches ~ 24%.
The rice is heaped to temper for 12-16 hrs.
During tempering, lumps are formed, which
are broken and mixed at least once. The
brown rice is heaped again
Drying ° Generally sun drying. Agitation done to
break the cakes. The moisture is reduced to
~ 10%
Puffing ° Roasting in hot sand (200-300°C). A
cylindrical roaster is used
Screening ° Perforated cylinder is used to separate murai
from sand
Grading ° Done by size screening process in a rotary
reel grader
Packaging ° Hygroscopic in nature because of large
surface area
° Packed in container with low water vapor
permeability
