Cereals and Legume Technology
Cereals and Legume Technology
Cereals and Legume Technology
Technology
FTNS-2109
Shahriar Ahmed, Student at Dept. of Food Technology & Nutritional
Science, Mawlana Bhasani Science & Technology University, Tangail.
2014
EMAIL: sahmed13041@gmail.com
Cereals:
Cereals are generally of the gramineous family and, in the FAO concept; cereals refer to
crops harvested for dry grain only. Crops harvested as green for forage, silage or grazing
are classified as fodder crops. For international trade classifications, fresh cereals (other
than sweet corn), whether or not suitable for use as fresh vegetables, are classified as
cereals.
Legumes:
Legumes are members of the bean family, Fabaceae, which includes all types of beans and
peas as well as soybeans, peanuts, alfalfa, and clover. This large, widely distributed family
also includes various trees and ornamentals such as black locust, wisteria, lupine, and the
Texas bluebonnet.
CEREALS LEGUMES
5 .Pod Cereals are not found within a Legumes are found within a pod
pod
Cereals:
Legumes:
Adzuki bean
Chick pea: Bengal gram, calvance pea, chestnut bean, chich, chich-pea, dwarf pea,
garavance, garbanza, garbanzo bean, garbanzos, gram, gram pea, homes, hamaz, nohub
Cowpea, asparagus bean, black eyed pea, black eyed bean, crowder pea, field pea, southern
pea, frijole, lobhia, kibal, nieve, paayap (Vigna unguiculata, syn.: Vigna sinensis)
Lentil, black lentil, brown lentil, green lentil, green mungbean, large-seeded lentil, red
mungbean, small-seeded lentil, wild lentil, yellow lentil, adas, mercimek, messer, masser,
heramame (Lens culinaris)
Mung bean, black dahl, black gram, black mung, golden gram, gram bean, green gram,
mungo, red mung bean, urd, chop suey bean (Vigna radiata, syn.: Phaseolus aureus)
Peanut, groundnut, earth nut, goober pea, mani, monkey nut, runner peanut, Spanish
peanut, Valencia peanut, Virginia peanut (Arachis hypogaea)
Cereals are very important part of human diets. The three major species, wheat, maize and
rice, provides a large proportion of the calories and protein in human diets.
Cereal grains contain 60% to 70% starch and are excellent energy rich foods for humans.
Doctors recommend cereals as the first food to be added to infant diets and evidence from
research upholds that healthy diet for adults should have most of its calories in the form of
complex carbohydrate such as cereal starch.
A healthy human diet must also include 20 to 30 g/day of dietary fiber, which can easily
achieved by eating whole grain cereal products such as breads, cookies or porridges.
The cereals can easily supply this quantity of protein, but unfortunately they lack the
essential amino acid lysine and therefore they must not be used as the sole source of
dietary protein. Adult woman requires about 50 g of protein per day, whereas an adult man
needs slightly more (about 63g).
In rural areas of poorer countries people may eat more than 500 g of cereal per day, which
will provide most of their protein needs.
Cereals are an excellent source of fat soluble vitamin E, which is an essential antioxidant.
Whole cereal grains contain 20% to 30% of the daily requirements of the minerals
selenium, calcium, zinc, and copper.
Unfortunately, bran contains substances such as phytic acid, which chelates minerals,
preventing them from being easily digested and absorbed. It is therefore important that
grain is processed correctly so that optimum nutrition benefits can be achieved.
Beans, peas and lentils all belong to the legume family. You may also hear them called
pulses, which is just another word for edible seeds. While their nutrient profiles vary a little
from one legume to the next, most of them provide minerals, such as iron, magnesium and
zinc. They all share two common characteristics: they're excellent sources of protein and
fiber.
OBJECTIVE:
Milling is a crucial step in post-production of rice. The basic objective of a rice milling
system is
-to remove the husk and the bran layers
-to produce edible rice that appeals to the customer- i.e. rice that is sufficiently milled
-to produce rice which is free of impurities.
- maximize the total milled rice recovery out of paddy minimize grain breakage
Most rice varieties are composed of roughly 20% rice hull, 11% bran layers and 69%
starchy endosperm.
1.Parboiling section:
-Cleaning elevator
-Boiler
-Tank
2.Drying section
-Dryer
3.Milling Section
-Husking machine
-Bran separator
-Polisher
-Whitening
-Color sorter
Q.8- Discuss the effect of different factors on milling yield and rice quality.
The rice millings by product are – Bran, husk, broken, germ etc.
a) Bran: the outer brown layer of brown rice & are composed of pericarp, testa &
aleurone layer.
Good source of protein, lipid, mineral etc & used as feed for animal.
Also good source of vegetable oil.
Used as fertilizer & soil conditioner.
Used to fortify bakery product at the level up to 15%
d) Germ: It is a good source of oil, protein, Vitamin-E & B complex & used to fortify
poor diet.
Q.10-Discuss the processes of multi-nutrient enrich rice with the help of a flow
diagram.
Rice Enrichment:
This coating is not soluble in cold water so nutrients cannot loss during washing but
coating are soluble in hot water so nutrient can uniformly dispersed during cooking.
To cut the processing cost, a small amount of rice is heavily fortified. This is called
premix.
Preparation of premix:
Rice can be enriched with thiamin, nicotinic acid & iron by this method but
riboflavin can not. Because it imparts a strong yellow color to the grain of the
premix which is un-desirable for consumer.
Require 100mg Ca/100gm rice. So it is difficult to make a premix with heavy
content of Ca.
# Enriched rice with nutrient which presents less or no amount in rice. E.g. - some
essential amino acid such as lysine do not present in rice. In this case the objective
is to add lysine with rice.
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Q.12-What do you mean by parboiling of rice?
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Q.13-What are the advantages of parboiling?
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Q.14-Discuss the principle of parboiling process
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Q.15-Draw, label and discuss the operations of a modern wheat flour milling process
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Wheat is one of the world’s most important grains, with annual world production of
540-580 million tons. Wheat is the most valuable of all food grains and widely used
in all its stages, from whole to finely milled.
In the bakery, wheat flour is the most important ingredients; it provides bulk &
structure to most of the bakery products, including breads, cakes, cookies and
pastries. Wheat is unique among the cereals in that--
its flour possesses the ability to form dough when mixed with water
the gluten in wheat dough has the ability to retain the gas produce during
fermentation
Or,
Elasticity, brittleness, toughness etc of bread depend on gluten.
- It raises loaf volume by retention of gas.
- Determine strength of flour & suitability for bread or biscuit making.
- Determine the texture of bread whether it is sufficiently firm or not.
Barley grain is rich in starch and sugars relatively poor in protein, and every low in
fate. The husk (lemma and palea) is mostly composed of lignin, pentosans, mannan, uronic
acids, hemicelluloses and cellulose fibres. Silica is present in the outer walls of the husk and
the awns contain large amounts of silica. The paricarp lacks lignin. The testa contains crude
cellulose and pigment strands of alpha waxes, which are a barrier for chemical substances
and microbes polyphenols which may complex with proteins are abundantly in the
pericarp, testa and aleurone layer. The aleurone has thick cell walls composed of
arabinoxylans and has aleurone grains of protein and phytic acid, pherosomes rich in fat
and abundant minerals. The subaleurone layer of the endosperm is composed of about 8.5-
8.9% starch enclosed in cell walls. b-glucans make up 75% of the cell wall and the rest is
arabinonxylons. The embryo consists of about 7% cellulose, 14-17% lipids, 14-15 %
sucrose, 5-10 % raffinose, 5-10% ash and 34% protein. The cell wall of the embryo
contains uronic acids, pectin and hemicellulose.
Milling of Barley
Barley is millet to make blocked barley, pearl barley, barley grots, barley flakes and
barley flour for human consumption. Removal of the hull or husk of barley, which is largely
indigestible is and important part of the milling process.
Intrinsic qualities : The milling is done in barley to achieve :
1. Absence of sprouting.
2. Absence of discolouration due to weathering.
3. Freedom from fungal attack and insect infestation or damage.
4. Soundness of appearance.
5. Absence of undesirable aroma or flavour.
The harder types of barley is best for milling purposes because the hull and bran can easily
be removed from endosperm by superficial abrasion and yielding particle will retain the
shape of the whole grain. The softer grains are not better because they would tend to
fragments, leading to a reduction in the yield of first quality products.
Barley for milling should have as low as hull intent as possible. The presence of
damaged grains lowers the quality of milling barley. Such grains frequently reveal areas of
exposed endosperm where fungal attack may occur leading to discolouration and intrigues
discoloured particles to the finished products. Thin grains also lower the milling quality
with a higher hull content than normal they make a small contribution to the yield of milled
products.
Operations : the sequence of operations in barley milling may be summarized as follows.
1. Preliminary Cleaning : Barley is cleaned on machines similar to those used for wheat
cleaning, viz. milling separators, drier cylinders or indented dishes, and aspirators. The
sizes of sieve aspirators and indents are modified for the comparatively larger size of
barley grains.
2. Conditioning : Conditioning consists in adjustment of moisture content to about 15%
by drying or damping and resting for 24 hour.
3. Bleaching : Barley is used to bleach with moisture and sulphur dioxide. Blocked barley
is fed into a vertical earthenware cylinder. Into which steam and sulphur dioxide are
injected. The quantities used are 1-2% of moisture and about 0.04% of sulphur dioxide and
solution of sulphurous acid (H2SO3) or of sodium disulphide (NaHSO3) can be. The
treatment take about 20-30 min time, after that the barley is binned for 12-24 hour for the
bleaching to take effect. Excessive quantities of sulphur residues in the final product should
be avoided.
4. Blocking and Pealing : Both blocking and pearling of barley are abrasive scouring
processes differing from each other merely in degree of removal of the superficial layers of
the grain batch machines or the rate of throughput in continuous working machine.
5. Aspiration : Aspiration of the pearled grain to removes the abraded portions and
cutting of blocked barley into portions known as grits and it is similar to those methods
done for aspiration of oatmeal. In Germany, the blocked barley is first cut into grits, the
grits graded by size and then sounded in the pearling machine.
All-purpose flour: This flour is the most widely used of all flours. It comes from the finely
ground partof the wheat kernel called the endosperm, which gets separated from the bran
and germ during the milling process. It is made from a combination of hard and soft wheat,
hence the term all-purpose. This type of flour can be used universally for a wide range of
baked products – yeast breads, cakes, cookies and pastries.
All-purpose flour has iron, and four B-vitamins (thiamin,niacin, riboflavin and folic acid)
added in amounts equal to or exceeding what is present in whole wheat flour. Virtually all
white flour sold in the United States is enriched (over 95%). There is no change in taste,
texture, color, baking quality or caloric value of enriched flour.
Bread flour is milled primarily for commercial baking use, but can be found at most grocery
Self-rising flour: This is a type of all-purpose flour that has salt and a leavening agent
added. One cup contains 1 ½ teaspoons of baking powder and ½ teaspoon salt. Self-rising
can be substituted for all-purpose flour in a recipe by reducing salt and baking powder
according to these proportions. It is commonly used in biscuits and quick breads or even
cookies, but is not recommended for yeast breads.
*Cake flour: This is a fine-textured, almost silky flour milled from soft wheat and has a low
protein content. It is used to make all types of baked goods like cakes, cookies, crackers,
quick breads and some types of pastry. Cake flour has a higher percentage of starch and
less protein than bread flour, which keeps cakes and pastries tender and delicate. (One cup
of cake flour can be made by measuring 1 cup all-purpose flour, removing 2 tablespoons of
flour and replacing that with 2 tablespoons of cornstarch.)
*Pastry flour: This typeof flour has properties that fall between all-purpose flour and cake
flour. It is usually made from soft wheat for pastry making, but can be used for cookies,
cakes, crackers and similarly baked products. It has a slightly higher protein content than
cake flour and less starch.
Semolina: This is the coarsely ground endosperm of durum wheat. Durum wheat is the
hardest variety of the six classes of wheat and has the highest protein content of all wheat.
Because of this, it’s ideal for making high-quality pasta and is used by both American and
Italian manufacturers. It’s also used to make couscous in Africa and Latin America, as well
as in the in the U.S.A
**Whole wheat flour: This flour is milled from the entire kernel of wheat. The presence of
bran reduces gluten development, therefore, items baked with whole wheat flour tend to
be heavier and more dense than those made from enriched flour. Bakers often add
additional gluten to counteract this. (one tablespoon/cup of whole wheat flour used)
**Stone ground: This is a type of whole wheat flour that has been milled by coarsely
crushing the kernel between two rotating stones. There is no nutritional difference or
advantage to milling the flour in this manner.
**Graham flour: This also is coarsely ground whole wheat flour. It is named after Dr.
Sylvester Graham, the creator of the graham cracker, who advocated the use of whole
wheat flour in the early 1800s.
Gluten flour: This has a high protein content usually milled from hard spring wheat. It is
used primarily to mix in with other non-wheat or low protein wheat flours to produce a
stronger dough structure. Gluten improves baking quality and produces a high protein
bread.
Q.23-Discuss the process of corn flakes with the help of flow diagram.
Breakfast cereal:
A breakfast cereal (or just cereal) is a food made from processed grains that
is often eaten with the first meal of the day. It is often eaten cold, usually mixed with
milk juice, water, or yogurt, and sometimes fruit, but may be eaten dry. Some
companies promote their products for the health benefits from eating oat-based and
high-fiber cereals. Cereals may be fortified with vitamins. Some cereals are made
with high sugar content
Pearl millet
Pearl millet, Pennisetum glaucum, is also known as spiked millet, bajra (in India) and
bulrush millet (Purseglove, 1972). Pearl millet may be considered as a single species but it
includes a number of cultivated races. It almost certainly originated in tropical western
Africa, where the greatest number of both wild and cultivated forms occurs. About 2 000
years ago the crop was carried to eastern and central Africa and to India, where because of
its excellent tolerance to drought it became established in the drier environments.
The height of the pearl millet plant may range from 0.5 to 4 m and the grain can be nearly
white, pale yellow, brown, grey, slate blue or purple. The ovoid grains are about 3 to 4 mm
Minor millets
Minor millets (also referred to as small millets) (Seetharam, Riley and Harinarayana, 1989)
have received far less attention than sorghum in terms of cultivation and utilization. They
include finger millet (Eleusine coracana), foxtail millet (Setaria italica), kodo millet
(Paspalum scrobiculatum), common or prove millet (Panicum miliaceum), little millet
(Panicum sumatrense) and barnyard or sawa millet (Echinochloa crus-galli and
Echinochloa corona) (Table 1). More information is available on finger millet than on any of
the others. Minor millets account for less than one percent of the foodgrains produced in
the world today. Thus they are not important in terms of world food production, but they
are essential as food crops in their respective agro-ecosystems. They are mostly grown in
marginal areas or under agricultural conditions where major cereals fail to give sustainable
yields. Detailed descriptions of these millets are given by Purseglove ( 1972).
Finger millet
Finger millet, Eleusine coracana L., is also known as African millet, koracan, ragi (India),
wimbi (Swahili), bulo (Uganda) and telebun (the Sudan). It is an important staple food in
parts of eastern and central Africa and India. It is the principal cereal grain in northern and
parts of western Uganda and northeastern Zambia. The grains are malted for making beer.
Finger millet can be stored for long periods without insect damage (Purseglove, 1972) and
thus it can be important during famine. Numerous cultivars have been identified. In India
and Africa, two groups are recognized: African highland types with grains enclosed within
the florets; and Afro-Asiatic types with mature grains exposed outside the florets. It is
believed that Uganda or a neighbouring region is the centre of origin of E. coracana, and it
was introduced to India at a very early date, probably over 3 000 years ago. Though finger
millet is reported to have reached Europe at about the commencement of the Christian era,
its utilization is restricted mostly to eastern Africa and India.
The height of cultivars varies from 40 cm to I m and the spike length ranges from 3 to 13
cm. The colour of grains may vary from white through orange-red deep brown and purple,
to almost black. The grains are smaller than those of pearl millet, and the mean I 000-seed
weight is about 2.6 g.
Foxtail millet
Foxtail millet, Setaria italica L., is also known as Italian, German Hungarian or Siberian
millet. It is generally considered to have been domesticated in eastern Asia, where it has
been cultivated since ancient times. The main production area is China, but S. italic a is the
most important millet in Japan and is widely cultivated in India (Purseglove, 1972). It is
believed to have been one of the five sacred plants of ancient China (from 2700 BC).
The height of the plants varies from 1 to 1.5 m and the colour of the grain varies from pale
yellow, through orange, red and brown to black. The 1 000-seed weight is about 2 g.
Common millet
Common millet, Panicum miliaceum L., is also known as prove millet, hog millet, broom-
corn millet, Russian millet and brown corn. This millet is of ancient cultivation. It is the
milium of the Romans and the true millet of history. It was cultivated by the early Lake
Dwellers in Europe. It is believed to have been domesticated in central and eastern Asia
and because of its ability to mature quickly was often grown by nomads.
The shallow-rooted plant varies in height between 30 and 100 cm. The grain contains a
comparatively high percentage of indigestible fibre because the seeds are enclosed in the
hulls and are difficult to remove by conventional milling processes. The 1 000-seed weight
is about 5 g (varying between 4.7 and 7.2 g). Common millet is particularly suited to dry
continental conditions and grows in more temperate climates than other millets.
Little millet
Little millet, Panicum sumatrense Roth ex Roemer & Schultes, is grown throughout India to
a limited extent up to altitudes of 2 100 m but is of little importance elsewhere. It has
received comparatively little attention from plant breeders. The plant varies in height
between 30 and 90 cm and its oblong panicle varies in length between 14 and 40 cm. The
seeds of little millet are smaller than those of common millet.
Barnyard millet
Barnyard, Japanese barnyard or sawa millet [Echinochloa crus-galli (L.) P.B. and
Echinochloa colona (L.) Link] is the fastest growing of all millets and produces a crop in six
weeks. It is grown in India, Japan and China as a substitute for rice when the paddy fails. It
is grown as a forage crop in the United States and can produce as many as eight harvests
per year. The plant has attracted some attention as a fodder in the United States and Japan.
The height of the plant varies between 50 and 100 cm.
Kodo millet
Kodo millet, Paspalum scrobiculatum L., is a minor grain crop in India but is of great
importance in the Deccan Plateau. Its cultivation in India is generally confined to Gujarat,
Karnataka and parts of Tamil Nadu. It is classified into the groups Haria, Choudharia, Kodra
and Haria-Choudharia depending on panicle characters. Kodo is an annual tufted grass that
grows to 90 cm high. Some forms have been reported to be poisonous to humans and
animals, possibly because of a fungus infecting the grain. The grain is enclosed in hard,
There is an optimum time for harvesting which depends upon the type of crop, its maturity
and local climatic conditions.
The main quality considerations are to harvest the crop after it has been partially dried by
the sun but before there is significant insect infestation.
A common practice that reduces grain quality is to harvest before the grain is sufficiently
mature and dry. Farmers may wish to harvest early to obtain the income, repay debts or to
avoid theft of the crop.
Grains that contain a higher level of moisture deteriorate more quickly because the
enzymes in the grain are still active and the moisture supports mould growth and insect
damage during storage.
Any grain placed in the store should be completely dried to the correct moisture
content (Table 5).
Maize 13.5
Millet 16.0
Wheat 13.5
However some grains, particularly maize and paddy that are left in the field after maturity
may become repeatedly moist from night-time dew or rain and then repeatedly dried by
the sun. This causes the grain to crack and become more likely to be infected with moulds
and infested with insects.
In mills the major hygiene problem arises from flour or bran dust which can collect on
ledges and floors unless a proper cleaning programme is implemented. If dust is allowed to
collect, it attracts insects which may breed to large numbers and contaminate good quality
flour. If dust accumulates above equipment it may become rancid or infested and then fall
as large lumps into the product, causing gross contamination. Accumulations of flour or
bran dust also attract rats and birds which contaminate grain and stored flour with hairs,
feathers and excrete. A cleaning schedule should therefore be implemented each day by
operators who have the responsibility and time to ensure that it is done effectively.
Flour mills and dehullers are potentially dangerous pieces of equipment and safety
procedures should be devised and strictly enforced. For example:
When grain is delivered to the flour or rice mill it should be inspected by taking a sample
from the batch. The sample should be carefully examined for the following quality
characteristics:
Primary processing
Cleaning
Depending on the outcome of the raw material inspection and the level of contamination
that is found, it may be necessary to clean the grain before it is milled. This is necessary for
two reasons: to prevent contamination of the finished product and to protect the mill or
dehuller from excessive wear or damage by sand or stones. It is usually sufficient to sieve
the grain to remove dust, sand, insects, small stones, weed seeds, etc. through a fine mesh
and retain chaff, leaves and larger stones on a coarse mesh.
Conditioning
Conditioning of grain before milling is important to ensure the proper separation of the
component parts of the grain and give a good yield of flour or in the case of rice, a good
separation of the hulls). A quality control check on moisture content should be made. Grain
that is too moist should be redried. If it is too dry a small amount of water is mixed in and
the grain is stored for 1224 hours and tested again for moisture content. Parboiling of rice
and subsequent drying has beneficial effects on both the efficiency of dehulling and the
quality of rice after storage. It helps to prevent rice grains cracking and also increases their
resistance to insect attack. The main quality control points are the time of parboiling and
the rate of drying.
Blending
The grain supplied to rural millers is in most cases, milled to a single flour which is then
sold. However, if millers are supplying bakers or other secondary processors, there may be
a demand for flours that have specific properties or for composite flours. It is then
Milling
The most appropriate types of mill for different cereal products depend on a number of
factors, including the type of cereal being milled, the degree of milling (or fineness) of flour
required, power consumption, required throughput, the capital that is available for
investment, the availability of spare parts and maintenance/repair facilities. Similar
considerations apply when selecting a dehuller. There is a very large range of milling
equipment available but there is insufficient space in a book of this type to describe the
different options in detail. However mills that are commonly used by small scale millers for
all types of cereals include plate mills, stone mills and hammer mills. Roller mills for wheat
are usually too expensive for small scale processors and are confined to large scale
centralized mills. Rubber roller dehullers are commonly used for rice hulling.
Other moving parts require a daily check to ensure that they have not become loose or out
of adjustment. A metal bolt falling into a mill can cause serious damage to the grinding
surfaces and metal filings from worn parts cause contamination of the product. The same
considerations apply to the routine checks on dehullers.
A further quality control check is to measure the range of particle sizes in the flour which
provides information on the degree of milling and the efficiency of the mill. Although the
sieves and shaking machine that are used for this check are relatively expensive, the
equipment provides valuable information to those millers who produce specialist white
flours. The equipment would not normally be recommended for small scale rural millers.
Sieving
In rural areas it is common for whole-meal flours to be sold by millers and in this case
there is no separation of the components of the grain after milling. Typically maize,
sorghum, millet and whole-meal wheat flours are produced by dehulling the grain, milling
to a flour and then using the flour directly to make the finished products. In other cases
there is a demand for a whiter flour in which the majority of the bran and germ is removed
to leave predominantly starchy material (for example maize, wheat and rice flours). This
separation is achieved by sieving the freshly milled flour through mesh screens, often fitted
with brushes to increase the throughput of the screens.
A quality control check at this stage of the process is to examine the sieved flour for bristles
that may have fallen from the brushes. The presence of a bristle acts as an early warning
that the brushes may need replacement. In addition checks should be made to ensure that
the flour does not contain insect eggs, insect parts or other types of contamination.
Jute or hessian sacks are commonly used to package flour or dehulled grain but multi-layer
paper and woven polypropylene sacks are increasingly being used. There are a few visual
quality checks that are done on sacks, mainly to ensure that they are properly cleaned, they
are not contaminated with other materials and they do not have holes or split seams.
Flours should be carefully filled to ensure that dust is minimised and that the amount in the
sack is the same as the net weight described on the label. In most countries it is an offence
in law to sell an under-weight product and over-filling means that the company is giving
away product at a loss
Once the cereal or flour has been sealed into a sack the risks of contamination by insects,
dust and micro-organisms are reduced but not eliminated. Incorrect storage conditions
such as exposure to sunlight, heat and water, can all result in spoilage. This is particularly
important because the expenditure that has already been made during processing makes
losses at this stage very damaging financially.
Sacks of flour or dehulled cereals should be stored on pallets to keep them off the floor of
the store-room The sacks should be carefully stacked as a poorly stacked block could
collapse and injure operators. The store-room should be cool and dark with a good
ventilation to maintain a flow of air. In particular windows should be screened against
insects and the structure of the roof and walls should prevent rats and birds from gaining
entry. The comments above on cleaning schedules should also include storerooms.
Staling is the process which result in a firmer bread crumb (a change from crisp to
leathery) sometimes accompanied by an undesirable flavor.
Staling results not from loss of moisture but decrease in the amount of starch. In the
presence of limited water as is the case with bread as soon as oven heat is removed, the
starch beings to undergo retro gradation.
Bread staling appears to be caused by the branched (amylopectin) fraction of starch.
Staling can be reversed by heating bread in the oven.
In the manufacture of bread softening agents (or, surfactants) are used to retard staling.
These softeners interact with starch & delay retro gradation. Some softening agents used
allowable under Australian food regulation, are sodium stearoyl, lactylates, esters of mono
& diglycerides & Diacetyl tartaric acid esters of mono & Diglycerides
Structure
It used in making foods for cattle, pigs and poultry and humans
It is used in jellies and gum
It is used in medicines and candies
It is used in food thickener and paper
Carefully selected starches help make yogurts and puddings
Other special food starches improve the flavor, texture, shelf-life and processing of a
variety of baked products.
Starch is also used as bakery fillings for cream and fruit pies and doughnuts
It is used as dry mixes for cakes and muffins, brownies and cookies
It is used as ingredients for jellies, cookies, glazes, icings and frostings
There are specialty starches used to help create reduced-fat and no-fat products
It improves baked goods rich in fiber
Dextrose is made from starch
Every time we eat rice or potato, we are actually eating starch. Starch provides us the
energy to work. In the form of carbohydrates, starches give the energy needed by humans.
Foods rich in carbohydrates are usually the most abundant and cheapest when compared
with foods high in protein and fat content.
Q.30-Extruded products.
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