processing and value addition of cereals

8/13/2019 Processing and value addition of cereals

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PROCESSING AND

VALUE ADDITION OFCEREALS



•Cereals are foods consumed in large quantity and at

greater frequency by a vast majority of population in the

world.

•Comprise the major segment of agricultural production of

any country.

•Cheapest source food energy and constitute high

percentage of calorie and protein intake of man particularly

in developing courtiers.

•They not only form staple food but also serve as an

important cash crops for commercial farmers.•Relatively easy to cultivate, store and convert into palatable

foods.

•Common cereals millet consumed in India are rice, wheat,

maize, pearl millet, sorghum, finger millet etc.

Cereals



Grain

Moistur

e

Carbohydra

te

Protein Fat Indigestibl

e fibre

Calories

(per 100 g)

Corn 11 72 10 4 2 352

Wheat 11 69 13 2 3 340

Oats 13 58 10 5 10 317

Sorghum 11 70 12 4 2 248

Barley 14 63 12 2 6 320

Rye 11 71 12 2 2 321

Rice 11 65 8 2 9 310

Typical Percentage composition of cereals



Cereal

Lysine Methionin

e and

Cystine

Threoni

ne

Tryptophan Limiting

Amino

Acid

Chemcial

score (egg)

Chemical Score

/FAO/WHO

Barley 216 246 207 96 Lysine 50 64

Cornmeal 167 217 225 38 Lysine 38 49

Millet 214 302 241 106 Lysine 49 63

Oats 232 272 207 73 Lysine 53 68

Polished Rice 226 229 207 84 Lysine 52 66

Rye 212 210 209 46 Lysine 49 62

Wheat flour 130 250 168 67 Lysine 30 38

Standard

Hen’s e 436 362 320 93 NIL 0 0

The nutritional quality of cereal proteins is not as high as that of most animal

proteins. Cereals grain proteins are deficient in certain essential amino acids,

especially lysine.Amino acid patterns of cereals compared with whole egg and FAO pattern:-

Amino acid patterns of cereals



Processing of cereals

for

value addition



Supplementation of wheat flour with 10-15per cent defatted germ flour brings aboutstriking improvement in nutritive value.

Addition of lysine, minerals and vitaminsincreases the nutritional value of wheat flour.

The additives like maturing agents, bleachingagents, self rising ingredients etc can also be

blended into flour to improve bakingcharacteristic.

Malting can also be used to improve thenutritional composition of the wheat.

Wheat can be used for development ofvarious products



Different milled products of wheat

•White flour-

used for the manufacture of bakery products and in the preparation of variousfried products and sweets.

It has 70% extraction from whole wheat milling.

•Semolina –

It is coarsely ground endosperm.

Used in the manufacture of macroni products and in the preparation of largenumber of savoury and sweet preparations.

•Resultant wheat flour –

Its yield is about 10% of whole wheat.

It consists of mixture of fine bran, shorts, clears and tail fines.

Can be used for the preparation of chapatti.

•Mill feed –

It consists of a mixture of bran, germ and shorts.

•Germ –

In roller flour milling process, germ is eliminated along with fill feeds. It can beseparated and used for the production of wheat germ oil.

The residual solvent extracted wheat germ is rich in proteins and B-vitaminsand can be used in the preparation of weaning foods.

•Wheat shorts –

An another fraction obtained in roller milling . It is found mixed with bran andgerm in mill feed.

•Bran – Wheat bran is used mainly as poultry and cattle feed



Hard –Soft wheat product

Chapati It is commonest product.

These days chapatti with long shelf

life, frozen chapatti are also available.

Flours for chapatti can be

supplemented with legumes like

chickpea, soyabean, barley to improvein nutritive especially protein and fibre

content.

Crackers, cookies, cakes, etc



Durumwheat



Rice is the staple diet for more than half of

the world’s population.

Carbohydrate constitutes bulk of the rice and

provide energy. Its protein content is lower

than wheat but quality of protein is superior.

However, when rice is eaten with pulses, its

protein quality improves due to mutual

supplementation of amino acids.

Parboiling is done to improve nutritive valueof rice.

Parboiled rice contains more B-complex

vitamin than raw

Rice



1. Cleaned for foreign matter.

2. Shelling or Hulling.

Shellers do not crush the grain but rub the outer layer ofhull from the underlying kernels.

3. Separation of hulls from the kernels by jets of air

4 Brown rice thus obtained are transferred to Milling (Polishing )machine.

In polishing machines, remaining inner layers of bran and germare dislodged by the rubbing action of the ribben rotor.

The endosperm with bran and germ removed is further polishedto a white high glossy finish.

The higher the degrees of milling or polishing the lower are the

remaining vitamin and mineral contents.Enrichment should be done to enhance the nutritional

quality.

4. Glazing can be done in the end. It is a coating of talcum powderand glucose done after polishing to give a transparent look torice.

Milling of rice



The by products of milling of rice are :-

1. Husk

• 20% of paddy by weight

• Contains cellulose, hemi cellulose and

pentosans.• Used for production of furfural and also in

manufacture of insulation boards.

2. Rice bran or polishing

• They constitutes about 8% by weight of rice

• Good source of protein (12-15%) and fat (15-

20%).3. Rice bran oil

• Prepared by solvent extraction of fresh or heat

treated rice bran with food grade solvents.

• Used as edible oil in some countries

• The solvent extracted bran can be used in

poultry or cattle feed.

By products of milling



•Two major ways to enrich rice.

Coating polished rice with enrichmentmixture, vitamins and minerals in powder formand then further coating the grains with waterproof edible film material.

Upon hardening, the film material prevents the

enrichment ingredients from dissolving away whenthe marketed rice is washed, as in commonpractice.

Parboiling or steeping the whole rice grains inhot water before removal of hulls, bran and germin milling.

Parboiled rice contains more B complex vitaminthan raw.

•The principal nutrients with which we need to enrich riceare thiamin, niacin, and iron. Thiamin is particularlyeffective in reducing incidence of beri beri where

polished rice is major item of diet.

Rice enrichment



Major processed rice

products

Rough rice Brown rice Milled rice Cooked rice

Popped rice Enriched rice

Precooked & quick

cooking rice puffed

rice

Canned rice, Congee,

Vinegar, Wines

Parboiled rice Broken Dry milled flour Puffed and

extrusion

Beaten/flaked & rice

Fermented (idli dosa)

Beer adjunct Breads, cakes

Crackers Muffins

Cooked rice

Puffed rice Puddings Antidiarrhoeal

preparation

Baby foods, Breakfast

cereals, Snack foods

Wet milled rice Rice starch

Cakes, various

noodles, (Flat andextruded)

Food stabilizer

Noodles



Fuel.

Food

sweeteners.

Alcoholic

beverages,.

Protein

Oil

Starch

Basicraw

material



Corn milling



The need for high-protein maize

•In Central and South America, Africa, and Asia, several hundred million people relyon maize as their principal daily food, and feed

•It lacks the full range of amino acids, :- lysine

tryptophan,

•Diets high in corn produce - wet-malnutrition

a person is receiving sufficient calories, but her or his body malfunctions due to alack of protein.

•Conventional maize is a poor-quality food staple; unless consumed as part of avaried diet – which is beyond the means of most people in the developing world – ittypically causes malnutrition.

•QPM produces 70-100% more of lysine and tryptophan than the most modern

varieties of tropical maize. These two amino acids allow the body to manufacturecomplete proteins, thereby eliminating wet-malnutrition.



People consuming QPM are

healthier and at lower risk

for

malnutrition disorders such as

Marasmus and Kwashiorkor



Use of dry milled corn products

Form of maize Use

Flaking grits Breakfast cereals

Coarse grits Breakfast cereals, Snacks

Medium grits Breakfast cereals, Snacks

Fine grits Brewing, Maize porridge

Meal Brewing, Snacks, Pancake waffle, muffins

Flour Traditional (laddu, foods, sattu, instant mix

(dhokla idli mix) pasta. Baby foods, Frozenfoods, Biscuits ,Cake, Wafers, Pancake

mixes, Meat extender, batters , Baked

products.Speciality products Confectionery toppings jam & jelly

extenders, Fig paste extenders, Coconut

extenders, Thickening agents, Dough

conditioners, Brewers flakes, Meat extenders



Value Added

Products From

Maize

CCSHAU, Hisar

Quality Protein

Maize (QPM)

Normal Maize

With

Soya bean /

Green gram

QPM with

Soya bean /

Green gram

(70:30)

(40/60/80/100%)

Normal Maize



Pulses are second to cereals as animportant source of human food.

They are considered as meat of thevegetable world and are close to animalflesh in protein food value.

Pulses are also termed as legumes.

The nutrient composition of ediblelegumes depends on the species.

In general their protein content is highand is commonly more than twice thanthat of cereal grain usually constitutingabout 20% of dry weight of seeds.

Pulses



• Nutrient composition of edible legumes depend onspecies.

• Important source of protein especially in avegetarian diet.

• Provide about 20-25 per cent protein that is doublethe amount of protein compared to cereals.

• Chiefly contain globulins.

• Albumins can also be seen in pulses.

• Deficient in methionine

• Rich in lysine hence, can supplement cereal protein.A mixture of cereals and pulses is superior to that ofthe either one

Nutritional composition of pulses



•.

•Contain 55-60 % starch. Soluble sugars, fibre and unavailable

carbohydrates are also present.• The unavailable sugar in pulses include substantial levels of

oligosaccharides of the raffinose family which produces flatulence in

man.

•Contain 1.5 % lipids on moisture free basis.

•Contain Ca, Mg, Zn, Fe, K and P .80% of phosphorus is present as

phytate phosphorus.

•Excellent source of B complex vitamins particularly thaimin, folic

acid and pantothenic acid.

•Contain some antinutrients which are toxic and interfere in the

absorption of other nutrients. The antinutrients present include:

trypsin inhibitors, lathyrogens , haemagglutinins cyanogenicglycoside

,saponins goitrogens tannins .

Some of the legumes which are commonly available



Some of the legumes which are commonly available

Common name Botanical name Other name

Bengal gram Cicer arientinum Chickpea, chola

Red gram Cajanus cajan Pigeon pea, Arhar

Black gram Phaseolus mungo Urad

Green gram Phaseolus aureus Mung

Lentils Lens esculenta Masoor

Cowpea Vignacatjang Lobia, Karamani, Black eyed

pea

Horse gram Dolichos biflorus Kulthi

Khesari dal Lathyrus Sativus -

Broad bean Vicia faba Bakla Avardi

Field bean Dolichos lablab Sem, Hyacinth Bean Machai

Haricot bean

Shell beanHorticultural bean

Phaseolus vulgaris Kidney bean

RajamahCommon bean, French bean

Lima bean Phaseolus lunatus Butter bean

Moth bean Phaseolus aconitifolius Mathi Dew gram Aconite bean

Peas Pisium sativum Matar



Processing of Pulses for value addition

There are two groups of pulses.

one is high protein and high oil group like soyabean, groundnut,

these are generally used for processing, their protein content as

high as 30-40% and oil content varies from 15-40% .

The second group comprises the moderate protein, pulses. These

pulses are important as human food like green gram, pea, lentil,

blackgram, mothbean, horsegram, field bran and prench bean etc.

Processing of pulses is of primary importance in improving

their nutritive value ad reducing the level of antinutrients.



Dh l illi



Dhal milling process

The process consists of the following steps:-

• Loosening of husk by conditioning with water in a specialconditioning equipment. Dehusking by means of specially

designed dehulling equipment.

• The yield of dehusked split legume is 80-85% by theimproved process as against 60-70 % by the conventionalprocess.

• Pulses mill: Pulse mill is an important machine forprocessing pulses like pea, gram lentil after they areharvested. Pulse mill dehusk an split these grains andmake them suitable for consumption. Pulses, before theyare milled are soaked in water and dried in sun and thenare fed into the unit for milling



•Legumes are generally milled to removethe outer husk and the resulting split

dehusked legume (dhal) is consumed aftercooking and is used in various food

preparation.•The methods used for the dehusking of thelegumes are :-

•Wet process

•Dry process involving conditioning the skinwith water or oil before dehulling.

•Improved dhal milling process.

Dehulling



•

The wet process has been commonly used withpigeon pea or red gram as the skin in this grain isdifficult to be removed. The process consists ofthe following steps.

•Soaking the grain in water overnight.

•Smearing the soaked grain with red earth mixedwith water and keeping the grain moist as a heapby sprinkling water for 6-24 hours.

•Drying the grain in sun.

• Dehusking the grain using granite or woodenhullers

Wet process



• i) Dry process after conditioning

the skin with water

•

This process is applicable to legumes such aschickpea, lentils, lathyrus, pea and dried peas.

• The grain are cleaned and after an initial sourcingor pitting operation in roller mills, they are sprayedwith water 5-10 % by weight of the grain and keptin a closed vessel for the water to be fullyabsorbed by the skin.

• The material is then dried in sun .

• The dried legume is passed through a roller mill.

• About 70-80 % of the grains are dehusked and

split simultaneously.

Dry process



ii)Dry process involvingconditioning

of skin with oil. This method is applicable to pigeon pea or redgram,

blackgram and green gram as the skin in theselegumes is tightly fitting on the endosperm.

The grains are passed through the roller mill forpitting the skin.

Vegetable oil (about 1-2%) is applied to the skin. Inthe case of green gram, the grains are coated with oilstraight away without preliminary pitting.

The grains are dried in the sun and then conditionedby spraying water (about 4-5%)

.The conditioned grains are again dried in the sunand dehusked using roller mill or Engelberg type ofrice huller



Pulse mill (dal mill) is animportant machine forprocessing pulses like pea,gram, lentil after they are

harvested. Pulse mill dehusk and split

these grains and make themsuitable for consumption.Pulses, before they are milledare soaked in water and driedin sun and then are fed into theunit for milling.



Traditional method of dry

milling of pulses



Dry milling of pulses – protein

isolate



Wet milling of pulses



Milling for highly

adherent pulses



ss

Secondary processing

Secondary processing of pulses is of primaryimportance in improving their nutritive valueand reducing the level of antinutrients.

Secondary processes also improveappearance, texture and cooking quality.

Such processes are directly involved in makingfood products or value added snack items

depending on the type of food and region ofconsumption.



S ki



Soaking

The grain legumes are often soaked

in water as a pre treatment to reducetheir cooking time.

Soaking has the additional

beneficial effects of either completely

or partly reducing the content of

undesirable substances such as

phytate,

trypsin inhibitors, tannin and

flatulence forming carbohydrates.



Germination

Germination helps to improvenutritive value of food pulses.

It has a specific role in terms ofreducing anti nutritional factorssuch as protease inhibitors, andoligosacchardes in legumes.

Protein digestibility is improved

with germination. In addition, it helps to develop

desirable flavours for certain foodproducts.



Fermentation

The processing of food pulses by

fermentation increases their digestibility,

palatability and nutritive value.

Fermented products that can be made using

legume include idli, dhokla, vedi nut etc.

Fermented products, could be prepared and

popularized, particularly in the country.



Roasting

Roasting is also useful in improving nutritivevalue of pulses.

These days roasted snacks are being

prepared from number of pulses.

Very specific snack items can be prepared by

the roasting process alone.

Although India is the largest producer of

chickpea in the world, there are only a limited

number of genotypes that are suitable for

making roasted products such as roasted

channa which is very commonly consumed as

snack item in the India subcontinent.The market demands for roasted chickpea is

very high and developed of genotypes for this

purpose will pay a rich dividend.



Flaking

Flakes can be prepared from pulses

like Soyabean using flaking machineand can be easily incorporated in

Indian dietaries.



Protein concentrates and protein

isolates

Protein concentrates and protein isolates

can be prepared from legume, contain and

approximately 50-60% and 80-90 %

protein, respectively.

The concentrate and isolate can be used

with and without blending with cereals in

preparation of convenience foods andsnacks to improve protein intake of



Quick cooking of pulses

The most serious draw back in theutilization of food legumes is their long

cooking time. Even through dehulling and splitting into

dhal reduces the cooking time.Considerably, the cooking process is time

and energy consuming.



Special soaking solutions containing

inorganic salts have been employed

for quick cooking of legumes

. Pectinase enzyme treatment

significantly decreases the cooking

time and also improves the general

acceptability of the products.



Greater emphasis is to be given for marketing the

new products of legumes.

For example, quick cooking dhal, also calledinstant dhal has good market potential.



Conclusion

Processing of cereal and pulses using suitable technique

and development of value added products will be beneficialin increasing nutritional potential of these crops.

Increased utilization of these crops using suitable

processing methods and their value added products may

not only be helpful in improving nutritional status of

population but will also help to raise economic standard offarmers.

processing and value addition of cereals

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