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Agricultural Support Systems Division

Food and Agriculture Organization of the United Nations

Rome 2004

Diversification booklet 4

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Brian Clarke

All rights reserved. Reproduction and dissemination of material inthis information product for educational or other non-commercialpurposes are authorized without any prior written permission fromthe copyright holders provided the source is fully acknowledged.Reproduction of material in this information product for resale orother commercial purposes is prohibited without written permissionof the copyright holders. Applications for such permission should beaddressed to the Chief, Publishing Management Service, InformationDivision, FAO, Viale delle Terme di Caracalla, 00100 Rome, Italy or bye-mail to copyright@fao.org

The designations employed and the presentation of material in thisinformation product do not imply the expression of any opinionwhatsoever on the part of the Food and Agriculture Organization ofthe United Nations concerning the legal or development status ofany country, territory, city or area or of its authorities, or concerningthe delimitation of its frontiers or boundaries.

© FAO 2004

ISBN 92-5-105071-6

iii

■ Acknowledgements v■ Preface vii■ Foreword ix

■ Some basic facts about village processing 1■ Benefits of using appropriate processing

technologies for creating sustainable livelihoods 5■ Choices and the factors that influence them 7

■ Business choices 7

■ Machinery choices 9

■ Crop choices 9

■ Some factors that affect choices 13■ How to do it: equipment and methods for

village operation 15■ Grain storage 15

■ Oil extraction 15

■ Rice milling 18

■ Maize milling 20

■ Crop cleaners 21

■ Cassava processing equipment 21

■ Cashew shellers 23

■ Supporting technologies required for village processing 25■ Machinery sales office or dealership 25

■ Rural machine-repair shops 26

■ Training and skills acquisition 26

■ Structures 26

■ Water 27

■ Packaging materials 28

■ Marketing 29

■ Transport 31

■ Disposal of waste 32

■ Further reading 35

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The author would like to acknowledge the sponsorship of FAO in writing thisbooklet and in particular to thank Peter Steele, Senior Agro-Industries Officer,Agricultural & Food Engineering Technologies Service (AGST), whose helpand encouragement made it possible, and Silsoe College, Cranfield University,UK, through whose support most of my experience in developing countrieswas gained.

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v

Acknowledgments

FAO Diversification booklets aim to raise awareness and provide informa-

tion about opportunities at the farm and local community level to increase

small-scale farmer income. Each booklet will focus on a specific farm or non-

farm enterprise or technology that experience has shown can be integrated suc-

cessfully into small farms or at a local community level. We explore the poten-

tial benefits associated with new activities and technologies, as well as appro-

priateness and viability in differing circumstances.

The main target audience for FAO Diversification booklets are people and

organizations that provide advisory, business and technical support services to

resource-poor small-scale farmers and local communities in low- and middle-

income countries. We hope to provide enough information to help these sup-

port service providers consider new income-generating opportunities, and how

they might enable small-scale farmers to take action. What are farmer require-

ments and constraints? What are critical “success factors”?

FAO Diversification booklets are also targeted to policy level people in gov-

ernment and non-governmental organizations. What actions might policy-

makers take to create enabling environments for small-scale farmers to diver-

sify into new income-generating activities?

It is important to point out that the Diversification booklets are not intended

to be technical “how to do it” guidelines. In order to provide farmer advisory

and support activities relating to introduction of new income-generating activ-

ities, most organizations will find it necessary to seek more information or

technical support. For these organizations, each booklet identifies complemen-

tary sources of information and technical support.

If you find this booklet of value we would like to hear from you. Tell your

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vii

Preface

colleagues and friends about it. If you have any suggestions where we can

make changes for the better in our next edition, or topics for other booklets –

this is equally important. By sharing your views and ideas with us we can

eventually provide better services to you.

Director, Agricultural Support Systems DivisionFood and Agriculture Organization of the United NationsRome, Italy

Most of humankind’s earliest tools –jars for storing grain or wine, grind-ing stones for making flour from ce-reals, threshing tools, winnowers andshellers – were designed to assist inprocessing and storing food. Thenineteenth century saw great progressin the development of machines forprocessing and storage, which led tobetter hygiene and nutrition. In thetwentieth century, vast improvementsin materials and production skills andincreased knowledge of crops shouldhave meant there was little that couldnot be achieved in the effort to plant,harvest, process and store all thecrops necessary for healthy, varied di-ets for most of the world’s population.Unfortunately, the reality of the situa-tion is very different: many people inthe world live well below an accept-able level of nutrition, and manymore face starvation.

This booklet presents an approachto improving the efficiency and pro-ductivity of crop processing at villagelevel in developing countries. Villageprocessing can lead to improved foodsecurity, greater prosperity and en-hanced quality of life for the vil-lagers. It requires improved tools andmachines on a scale larger than that

required for the immediate family. Similar undertakings in the past

were often too large or too optimistic.That is why this booklet highlightssome of the requirements and dangersof developing a village enterprise andincludes steps to secure funding andcreate simple business plans that offera good chance of early repayment ofloans. Village processing should notmake abrupt changes to lifestyles orcultures; it should gradually eliminatesome of the more inefficient practicesand so improve the overall standardof living for all those affected bychange. This may be sufficient togenerate household incomes that willenable children to go to school andprovide local people with more food.Simple machines can make it possibleto grow a wider range of crops, in-cluding those that would be difficultto process manually.

These proposed village operationsare best suited for products that needto be processed in large volume. Theyoften need cooperation or input byseveral farmers or perhaps an entirevillage. Individual family operations,on the other hand, are often limited totraditional techniques that rely onmanual operation. Finished food

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Foreword

ixix

FIGURE 1 Gari production at a village in Benin.

xx

products for retail are often success-fully produced using traditional tech-niques.

To be able to help, communities,planners and policy-makers need toknow the potential for any crops thatmay be grown in identified areas. Inthe long term, infrastructures may

need to be developed to take advan-tage of world market demand for suit-able crops. Account has to be taken ofprevailing socio-economic factorsand local customs and culture. An ad-equate support system will reduce therisk of failure for a farmer who mustoften rely on guidance from a local

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FIGURE 2 A simple covered building for gari production in Benin, adequate for keeping therain off.

xixi

shopkeeper who is only looking for aquick sale. By identifying the criteriafor successful village processing, itbecomes possible to extend thosegood practices and their benefits tovillages anywhere in the world.

Processing at village level, even indeveloping countries, has been prac-tised for many years and certainly forthe past 150 years, as settlers from in-dustrialized societies took their skills,tools and machines with them as theymoved into agrarian societies. Localmanufacturing has developed incountries of Africa, Asia and LatinAmerica only in the last 50 years. Lit-tle progress had been made in thosecountries to utilize wind, water orsteam power, despite widespread usein industrial countries. In moderntimes, with the introduction of thediesel engine and the electric motor, awide range of processing machinescan be found in most countries, butfor various reasons they still are not

available to a vast number of peoplewho could benefit enormously. Manypeople are trapped in poverty becausethey lack the knowledge, opportunity,capital or outlets to process and selltheir produce.

Community members must de-cide together whether they want totake on the added responsibilitiesnecessary to develop into a moreprosperous, secure society. A vil-lage’s primary resource is its crops;adding value to the crops makes itpossible to generate funds. This firststep could lead to changes in cen-turies-old techniques and traditions,setting up systems for better foodproduction, income generation andvastly improved quality of life. Vil-lagers must take a hard look ahead.They must decide how they wanttheir communities to develop andlook at the possibilities for produc-ing viable goods that will help themto achieve their aims.

xiixii

As much as 50 percent of food is lostbetween harvest and consumption,often because of poor storage facili-ties that allow moisture, fungus, ro-dents and insects to take their toll. Im-proved storage and early processingsuch as drying can greatly reducethese losses. The increased food sup-plies can then be sold, or the land canbe used for an alternative cash or foodcrop. Much of the labour involved infood production and processing isdone by women and children, labourthat brings few rewards when lossesare high. Finding ways to improveproduction decreases labour de-mands, saves food and time and canhelp to improve family living condi-tions and cultural development. Chil-dren can focus more on education andplay, instead of having to take onfamily responsibilities at an early age.

All crops differ physically and bi-ologically, and so require specializedprocessing. Cassava, for example, de-teriorates within a few days after har-vest unless it is dried or made intogari. Yams are a similar crop, but canlast much longer in a fresh state. Achipper, which is a simple processingmachine, can help to expose cassavafor rapid, easy drying in the sun.

Oil is highly valued throughoutthe world for cooking and as a sourceof energy and flavour. Manual or mo-tor-driven machines are well suited toextract it: manually operated bridgepresses for groundnuts and ram press-es for sunflower and copra extracthigher-quality oils with less effort anda higher percentage of oil extraction.Where they are used, these machinesare very popular because they saveeffort and increase production and be-cause the availability of oil improvesdiets and leads to improved health.There are many villages, however,with no knowledge of these machinesor no opportunity to use them.

It is often wealthier farmers withthe ability to raise purchase capitalwho can own and manage these ma-chines. They become even wealthierif other farmers pay to use their ma-chines. They can then buy other ma-chines and process other crops, whichputs them in very powerful positions.But if a group such as a farmers’ or-ganization or cooperative invests in amachine, the standard of living of theentire group can be improved; lendersmay be more willing to make a loan ifa group of farmers is sharing respon-sibility for repayment. For those

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1

Some basic facts about village processing

without land or other resources, ma-chinery can mean new opportunitiesfor employment. This will in turn dis-courage people from migrating tolarger towns or cities in search of em-ployment and provide greater securityto the entire rural community.

Training can often be made avail-able through local extension services.As the community is strengthened,management skills, machinery work-shops, dealerships and communica-tion networks can be introduced asappropriate. As the village becomesmore secure, schools, medical facili-ties and other services can follow. Inorder to begin the process, however, awide range of factors needs to bechecked, because shortfalls in anyone of these could lead to failure.

This booklet shows that if certainmethods are followed, it is not toodifficult to establish a viable businessthat operates efficiently and enjoysreasonable stability. National institu-tions favour small- and medium-scaleenterprises for good reason: they havethe potential to improve the overallprosperity of the country, eventuallyimproving the balance of payments,increasing export potential and im-proving food security for the growingurban populations.

Loan and aid schemes can supportthe introduction of small-scale tech-nology into poor areas, which oftenoperate under traditional barter

economies and where cash crops havenot been available. The schemes existin the tropics and in temperate cli-mates in countries where agriculturalpatterns are changing, partly as a re-sult of political changes. In suchcountries, there is often a growingneed to become self-sufficient in foodand to attain a higher level of internalsecurity and economic prosperity.

The water pump and the grain millare the two machines that usually of-fer the greatest benefit to a village. Inmany villages, women spend up totwo hours every day grinding food,usually grain, using a traditionalmethod such as a quern consisting oftwo circular stones. In Africa, an esti-mated 50 percent of all villages stillpound grain in hollowed out logs ortree stumps. Imagine the time and ef-fort that could be saved with a mecha-nized operation.

Before seeking funding and adviceto initiate a mechanized operation,however, a wide range of factors mustbe considered. The first is the marketfor the produce. This might simply bethe local community, or there may becommercial markets to consider if thevillage is within reasonable travellingdistance of a town by bus or collec-tion truck. If a farmer needs to grind 2kg of grain each day for home use,and the smallest machine is capableof grinding 80 kg per day, the farmerwould be able to process enough

2

grain for 39 other families. In order totake advantage of this spare capacity,many machines are operated as abusiness with a manager or entrepre-neur employed on a full or part-timebasis. Because a machine may cost upto US$3 000 and the means must befound to pay for it, the business mustbe linked to a cash economy at somestage. Machines can be paid for withgrain or flour, but a system has to beput in place to organize this. When amachine is simply given as a form ofaid, it does not foster independence asit would when there is some form oforganized payback system.

Socio-economic factors must beconsidered too. When women use ma-chines, they save as much as two hoursof work each day. They might miss thesocial aspects of being together topound their grain, although the timecould be spent in further processing. Inthe case of cassava, for example, thereis the incentive of adding value to theproduct by making the fermented androasted product known as gari or fari-na, rather than the raw roots. Mostcrops lend themselves to further treat-ment or processing, leading to a higherand more consistent quality and fewerlosses.

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3

There are three common scales orlevels of processing: domestic, vil-lage and factory. Before looking atvillage-scale processing, it is worthconsidering some of the limitations ofdomestic and factory-scale process-ing.

Domestic processing is limited tosmall-scale production and can be ofvariable quality. It is suitable for theimmediate family with a little extracapacity for local market or roadsidesales. Because domestic processingcannot take advantage of poweredmachinery, except where an electricalsupply is available, it cannot havemuch influence on the community.

Factory processing and productionhas the potential to transform a socie-ty from mainly subsistence farmers tofactory labourers. The community asa whole often does not share the prof-its, however, and the traditionallifestyle is lost. The labourers mustspend the money they earn on foodand clothing and housing is oftenpoor. The attractions of the factoryapproach are that large amounts offood can be produced and processedand the national economy can be im-proved by sales on the world market

of such products as coffee and cocoa.If factories are too big or not wellplanned, massive investments may belost and local lifestyles, cultures andtraditions can be badly and often irre-trievably affected.

Village processing is the alterna-tive approach. At village level, the ad-dition of machines for production of-fers many advantages: • reduced post-harvest losses;• food supplies throughout the year;• opportunities to produce a cash

crop;• possibilities of growing and pro-

cessing alternative crops;• added value to crops before sale;• less tedious processing tasks; • increased leisure or opportunity

time;• reduced danger in some processes. With production at village level, localcommunities can be made more pros-perous without substantially changingtheir cultures.

Machines reduce the danger as wellas the tedium of processing tasks, oftenproviding much higher quality products.Rice is easily husked by machine, whilea hand-operated tool requires very hardwork and often results in high losses be-

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5

Benefits of using appropriate processingtechnologies for creating sustainable livelihoods

cause of the number of broken grains.Without powered machines or tools, itprobably would not be worth growingrice in many areas. The same is true forsuch crops as coffee, cashew and tea.Cleaning crops with a sieve is anotherdifficult process to carry out by hand,whereas a cheap mass-produced sievethat is either shaken by hand or drivengives a precisely sized product everytime.

There are many situations wherepost-harvest losses can be reduced. Aproperly dried and stored productsuch as grain in a steel silo can last foryears with little deterioration, where-as a damp, exposed heap of grain willusually deteriorate within a few days.Machines that save time and produceextra food for those who use them canalso provide the opportunity to growcash crops.

6

There are many areas in the worldwhere there are no machines but veryreal needs. This booklet addressesthose situations where there is stillample scope for village development.

■ Business choicesIn setting up any business, it is firstnecessary to establish the potentialfor the sale or use of the product. Al-though a major advantage of a pro-cessing business is avoiding thedrudgery of daily tasks such asshelling, grinding or cleaning, there isno way to pay for machinery if theproduce is only for personal con-sumption. That is why it is importantto be aware of following alternativeownership scenarios and outlets.

OwnerThe owner or owners may be:• a single farmer in a village;• a group of farmers in the same vil-

lage;• a manager or entrepreneur;• an outside investor.

Sales/outlets for productsThese may be:• the inhabitants of a village;• the inhabitants of other villages;

• the inhabitants of nearby townsand cities;

• transport entrepreneurs;• national merchants.

A simple business plan must bemade, even if it is not on paper. Thesecurity of the business for severalyears is essential. If a machine has tobe paid for within a certain period,then the markets for the produce plusthe likely profits must be clearly iden-tified. Market research sounds compli-cated, but it is essential to determinepotential sales of the products and tobe aware of any factors that may influ-ence these projections. Discussionswith other farmers, neighbours or trib-al elders can raise awareness of theplans and objectives of other farmersor groups in the area. This is a way toavoid being in competition rather thancooperation with others, so that profitmargins do not suffer as each tries toremain profitable.

If only one person in the communi-ty owns a machine, it places others ata disadvantage. Their unprocessedproduce may not be able to competewith processed goods and may remainunsold. Other villages may suffer inthe same way, and suddenly a wholearea may actually be destabilized

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7

Choices and the factors that influence them

rather than secured. It is better to sharethe risks and benefits rather than focuson a single farmer. One way ofachieving success is to include asmany people as possible in the deci-sion to invest in machinery and sharethe risks. This leads to a wider senseof ownership and responsibility and,with luck, to a larger customer base.Investigation may show that the mar-kets are wider than anticipated andthat local townships may be in need ofparticular kinds of food, especiallywith the growth of urbanization.Knowing this in advance means that abigger machine could be bought, lead-ing to more efficient operation andmore opportunities for employment inthe business. This may often need out-side help from non-governmental or-ganizations (NGOs), donor agenciesor local government officers. Oncesufficient development has takenplace, roads, telephones, electricalpower supplies, improved water sup-plies, drains and agricultural supplyfacilities can become part of the over-all plan for the area.

Funding for new technology maycome from a variety of sources. Aidagencies have funded numerous ven-tures in the past. Banks have alwaysbeen ready to make safe loans, but of-ten at high interest rates that increasethe risk to the farmer. Governmentloan schemes may be safer, but theyare not always easy to obtain. Dealers

will often be prepared to set up ascheme, but their interests are purelycommercial, so the buyer’s best inter-est is not always served. Inappropriatemachines are often sold in this way.Farmers without education or trainingwho live in an unstable environmentare not good risks for loans. Evenwhen they can pay in cash from theirsavings, they must identify a reliabledealer who will give them the best ad-vice. Local extension services can bevery useful in making farmers awareof issues such as competition, avail-ability of loans, recommended dealersin the area and technical advice.

Commercial development canstimulate the local economy. Largecompanies may select an area as suit-able for growing a particular cropsuch as coconut or groundnut andmake advances to the local communi-ty with a view to buying the primaryprocessed product. They may even beprepared to provide the initial invest-ment for village processing machin-ery. Commercial crops are oftengrown on a larger scale, but certaincrops lend themselves to local pro-duction. The presence of a large in-vestor can help significantly in theprovision of machinery, high qualityseeds, fertilizer, growing informationand market opportunities. The suc-cess of such developments dependson the degree of the community’s de-pendence on the investor. Each party

8

has to protect its own interests, whichcan create difficulties. It is usuallybetter for the community to retain itsindependence without being restrict-ed to a single crop. Quality standardshave to be maintained: for example,farmers who process their maize ontheir farms may spoil it with low-quality processing, while processingby a central store or trader may resultin a higher-quality product. Tradition-al crops should still be grown andprocessed, so that lives are changedas little as possible. Introducing newcrops and processing facilities, how-ever, increases the chances of greateremployment, greater security andsustainable futures.

■ Machinery choicesEven if the choice of machine seemsstraightforward, it is still necessary togather as much information as possi-ble. It is preferable to see machines inoperation elsewhere and discuss themwith the owners. Dealers may have arange of types and sizes to offer andshould be able to give guidance, butextension officers and current ownerswill probably be able to give the bestadvice. The money available and thepotential of the machine will obvious-ly be major influences.

Machines should ideally last at leastten years; some might give good serv-ice for more than 20 years, while oth-ers will have shorter lives for a variety

of reasons. Regular maintenance is akey factor, requiring the availability ofspare parts and repair skills. Many pro-cessing machines are like the prover-bial axe: it will last forever as long asnew heads and handles are availableand the cost is not prohibitive. A reli-able supply of raw materials and fuelis needed to keep the machines work-ing and retain people’s trust in the sys-tem. As soon as confidence wanes, thebusiness will be under threat, especial-ly if there are alternatives.

■ Crop choicesResearch and consultation into all al-ternatives should be conducted beforedeciding on a new cash crop. Process-ing staple foods does not require asmuch information, except in thechoice of machine. Crop choiceshould be decided right from the start,based on full discussions to determinelocal needs and preferences. It cantake time to introduce new crops andfoods. Maize and cassava, for exam-ple, were not grown in Africa untilrelatively recently, yet now they arewell established staples.

Hybrid varieties of sunflower havehigh oil yields and will grow in mostparts of the tropics. New varieties ofcassava and maize are being devel-oped for improved disease resistance,flavour and yield. Although oil fromgroundnuts, seeds or fruitlets can bereadily extracted by machine and usu-

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9

ally finds a ready market, it is tradi-tionally a slow, tedious process, whichmakes the oil relatively expensive.

Communities are often undernour-ished. As part of their development,new crops may be suggested that willdiversify their diets, along with themachinery to process them.

Many enterprises fail because thesupply of raw crops fails. Failure mayresult from a bad harvest caused bydiseases or adverse weather condi-tions, or because alternative marketsfor produce are opened. Studying theexperience and history of a localitycan help to give a reasonable guaran-tee of material supply. Confidence insupply is greater if farmers buy ma-chines to process their own crops andif their crops are sufficient. If not,other sources of crops for their ma-chines to process should be investi-gated before launching into new en-terprises. The prior agreement of thevillage as a whole to support or usethe new technology adds greatly tothe security of any business.

Energy and power choicesIf a farmer or group does not want toinvest in motor power, or there is noinfrastructure to support it, energycan be supplied by water, wind, ani-mals, the sun or hands and feet.

Water power, once widely used indeveloped countries, is only an optionwhere there is a suitable water supply;

mountainous countries are often wellsupplied with water. Designs areavailable for a range of high- andlow-speed machines powered by tur-bines or waterwheels. If there is a re-liable supply of water, it should be thefirst option considered, because watercan provide high power at high speedif it is available at sufficient heightand quantity. Minimum water re-quirements for small slow-movingwaterwheels are about 0.5m3 perminute at a height of 3 m. A medium-sized pair of grinding stones 0.6 m indiameter will use about 0.5 kW.

Wind power has been used suc-cessfully in many countries. Thewindmill is a typical example of agrain-grinding machine. Winds areoften unreliable and light in the trop-ics, however. Unless a region – per-haps an island – is known to have areliable source of wind power, it israrely a viable option for driving pro-cessing machinery.

Animal power is a choice in com-munities where animals are tradition-ally used for work. Donkeys, buf-faloes, camels and oxen can all beused for processing crops; the ma-chines have to be designed to suit theanimal. The power is clearly providedat very slow speeds of about1 rev/min, but at relatively hightorque. Threshing, oil extraction andgrinding are suited to animal power,provided the machine is designed to

10

run in this way. In contrast, a machinedriven by a motor has an input speedof at least 500 rev/min.

Solar power is abundant in thetropics and should be utilized wherepossible for drying operations. Rainprotection, simple solar collectorsand aids to air flow can transform arisky, inefficient process into a reli-able and efficient operation with lit-t le investment. Cassava, yams,spices, fruits and vegetables can allbe preserved with solar dryers andstored for seasons of food shortage.Ventilated polythene covers on anA-frame can make a simple, inex-pensive drier. More sophisticatedtypes are available.

Biomass is a by-product of suchcrops as oil palm, rice, maize andsugar cane and can be used as a fuel

for drying if it is available in suffi-cient quantities. Careful planning isrequired, however, to make sure thatthe system is sustainable and reliable.There is, for example, sufficient ener-gy available in rice husk to drive acomplete rice process plant if themeans is provided to convert the en-ergy into rotary power. Biomass hasbeen used in the past to drive steamengines, but this is an unusual optionthese days.

Methane is a product of wet wasteorganic material. It is the natural gasthat is produced in enclosed contain-ers and makes an excellent fuel fordiesel and petrol engines. By-prod-ucts from fruit and vegetable process-ing plants and any other green trim-mings can be used for methane pro-duction, as discussed later.

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FIGURE 3 Solar drying rice in Sri Lanka.

Hand or foot power can be usedfor a wide range of machines and toolsthat are available for small-scale pro-cessing. In the earliest stages of devel-opment, especially in remote regions,it is often wisest to start with manualor animal-driven machines; in peri-ur-ban areas, electric or motor-drivenmachines are often more appropriate.

Diesel and petrol engines canrange from 3 kW up to about 25 kWfor village-scale operations. Dieselengines are more reliable than petrolengines. They cost more initially butare cheaper to run. Many diesel en-gines in developing countries haverun for decades. Diesel engines areoften used to drive generators, which,supply power to electric motors,lights and office equipment. A manualworker can sustain an output of about75 W for some time, but a diesel en-gine can produce its power rating, say

3 kW, continuously. This gives up to40 times the output and saves the ex-pense of the worker’s wages. Enginesdo not require breaks or holidays, butthey do require a substantial cash in-vestment and a reliable supply of fuel.

Training in the care and mainte-nance of engines is essential. The firstchoice of motor and fuel would usual-ly be diesel, provided diesel fuel isreadily available. This fuel is alsosuited to tractors and many transportvehicles. If the enterprise has accessto electricity, however, this would bethe immediate choice because it ischeaper and simpler and more reli-able in every way to operate. Electricmotors are quiet, easy to start andcleaner; they produce no fumes andare available in a wide range of sizes.The main object of this booklet, how-ever, is to address the needs of re-gions where there is no electricity.

12

FIGURE 4 Hammer mill in the Congo driven by a diesel engine.

It is impossible in this small bookletto cover in depth all the issues thatcan influence the choice of crops, ma-chinery and power. The following arethe more important issues:• potential local and regional mar-

kets for products; • prospects for growth in the mar-

ket;• availability of a reliable and ap-

propriate energy or fuel supply;• crops that grow reliably in the

area;

• availability of machines and main-tenance;

• availability of cash from savingsor loans;

• awareness of who will be affectedby the introduction of a new ma-chine;

• opportunities for cooperation withother potential buyers;

• understanding of the currentlabour situation;

• appraisal of personal preferencesand wishes.

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Some factors that affect choices

■ Grain storageIt is important to choose a watertight,rat-proof, insect-free container inwhich crops can be stored for at leastnine months. Galvanized steel makesvery good silos, but it usually needsto be imported, which requires signif-icant investment. The resulting sav-ings may permit rapid repayment,however, if surplus grain can be sold.Surpluses thereafter are for profit.Most societies have devised somemethod of storage, but rats and otherpests often cause significant losses. InIndia, losses are estimated at up to50 percent. Such figures are hard tosubstantiate, but the author has seencomplete stores with every grain lost.The benefits of good storage are over-whelming. Even the use of improved,locally made stores with rat guardsmade from chicken wire plasteredwith mud or, preferably, cementwould be a major improvement inpreserving crops.

Small stores can be made fromused 200-litre oil drums. They can beespecially useful for storing sufficientseed grain for sowing the followingyear. A tight-fitting lid keeps out wa-ter and insects. Other stores can be

made entirely from local materials.Sun-baked mud over pliable stickswoven to make a grain store can bevery effective and can be made to awide variety of local designs. Someare better than others, however, andsharing knowledge of the best tech-niques pays good dividends.

■ Oil extractionIn recent years, major advances have

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How to do it: equipment and methods for village operation

FIGURE 5 An improved grain-storage silomade from local materials in Malawi.

been made in extracting oil from thefruitlets of groundnuts, sunflowersand palms. The traditional ways ofprocessing these crops – pounding,roasting or kneading – are tedious andinefficient. The Bielenberg leverpress, designed to operate manuallyand replace many of these operations,offers an alternative. With it, one op-erator can produce 2-3 litres of oil perhour from sunflower, copra, sesameand several other types of oilseed.Significantly, this machine is manu-factured in developing countries andhas proved successful in East Africaand other regions. On a slightly largervillage scale, a group of farmersmight be able to afford, supply and

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FIGURE 6 A Bielenberg lever press extracting oil from hybrid sunflower seeds in Zimbabwe.

FIGURE 7 Traditional kneading of oil-palmfruitlets after steaming to make oil to be usedin a village in Benin.

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FIGURE 8 Traditional washing out of the oil after kneading.

FIGURE 9 Larger-scale palm oil extraction in Benin at fruitlet selection stage.

operate a motorized screw press withthe same crops, yielding 15 litres perhour with very little manual labour.With careful filtration, there is eventhe possibility of using the oil that hasbeen pressed to run the diesel engine. Palm oil is traditionally produced byboiling, kneading and washing.Steaming and pressing in a manualscrew press is a simpler alternative.Many such machines are availableand made in rural workshops in manyparts of the wet tropics. Ground nutsare probably processed best with abridge press after the nuts have beencoarsely ground, wetted and roasted.It is a simple machine that produces

up to 3 litres of oil per hour.

■ Rice millingRice, the staple of Asia, can be storedunmilled until it is required for eating.At that point, a rice mill can removethe hard husk and polish the kernel.This system makes it possible to keepthe mill working throughout the year,as long as stocks of unmilled rice re-main. Traditional rice processingdoes not really compete with machinemilling, so mill owners will not dis-turb the local labour balance, al-though eating habits may be affected.Different types of rice mills are avail-able. National preferences may dic-

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FIGURE 10 Larger-scale palm oil extraction in Benin using a screw press.

tate whether an under-runner disc, arubber-roll or an Engelberg millwould be the best. This often dependson the ability to share existing knowl-edge and experience, and the knowl-edge that support can be obtainedquickly if trouble arises. The under-runner disc mill is very popular on theIndian subcontinent, for example, butvirtually unheard of in Africa; thereis, however, some pressure to adoptthe rubber-roll mill, which producesfewer broken grains. If there were nosuch preferences or constraints, theauthor would suggest the Engelbergas the best village-scale mill. It is rel-atively inexpensive, robust and readi-

ly repaired. It has few moving parts towear out and provides an acceptablequality of rice. The skills to operateand maintain this machine can belearned quickly. On the other hand,only the small domestic machines aremanually operated; others are drivenby diesel motor, which may be toomuch for some villages. Because anew engine and mill cost aboutUS$3 000, a large sum of money to asubsistence farmer, careful planningis needed.

Farmers have in general been themost likely people to buy rice mills.They have the raw, unmilled rice, cansee the added value that comes from

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FIGURE 11 Parboiling rice in concrete tanks in Sri Lanka.

milling the grain and can easily installthe equipment on their farms. Theycan set up a small building and mayhave access to labour or a familymember to operate the mill. Theymay transfer some of their existingtasks in order to concentrate on themilling, which requires skill in opera-tion and management. Most farmerswould wish to keep an item represent-ing such considerable investment un-der their personal control.

Eventually, facilities for parboil-ing, drying, cleaning or polishing themilled rice can be linked to the enter-prise and will add value to the fin-ished product. At this level, the rice

can be sold directly into the retailmarket; unmilled rice is mainlybought by traders.

■ Maize millingThe maize mill for producing fineflour has been probably the mostwidely accepted processing machinein Africa because of its obvious ad-vantages over pounding or scrubbingstones. Grain mills can be hand-oper-ated, but can easily be readily motor-ized, saving a good deal of physicaleffort. The most efficient manual sys-tems are the plate mill or stone quern,but these are still laborious methodsyielding about 5 kg of coarse flour

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FIGURE 12 Rubber–roll rice mill in Liberia.

per hour or 1 kg of fine flour. Thesmallest hammer mill with a 3 kWdiesel engine will produce about150 kg of similar coarse flour perhour or 50 kg of fine flour. The sav-ings in labour are dramatic. The mealis ground through a sieve of fixedsize, so the quality is always thesame; manually prepared flour can bequite variable. The main choice ofmachine is between the plate mill andthe hammer mill. The hammer mill isthe more popular of the two and canbe supplied in larger sizes if required;an inexpensive, locally made versionis often available with easily fitted

spare parts, although certain partshave to be imported. The plate mill isusually only available up to about7 kW. The whole machine is usuallyimported, and even the spare parts aredifficult to make. The choice of milloften comes down to availability andlocal preferences. The plate mill cangrind both wet and dry products; thehammer mill is confined to dry prod-ucts. Both machines are capable ofgrinding a wide range of materials,which may be a means of wideningthe scope of a business.

■ Crop cleanersCrops can be cleaned more easily bymachine than by hand. Perforated-plate or wire-mesh sieves cannot beconstructed locally, but they are im-ported fairly inexpensively and aredesigned to give a guaranteed productsize. Nuts, seeds, grains, coffee,spices and various types of chipped orextruded foods are suited to cleaningby mechanical sieving machines.Many models incorporate a winnow-ing fan that cleans light material suchas chaff or dust from the product byair blast during the sieving process.The output of even the smallest 3 kWmotorized cleaner is about 5 tonnesper hour.

■ Cassava processing equipmentCassava processing lends itself tomechanization for several products,

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FIGURE 13 Locally made plate mill inNigeria, used for wet and dry products.

such as dried chips, starch and gari.Gari is a popular food in West Africaand in South America, where it isknown as farinha de mandioca. Chipsare made by a chipping machine,which usually consists of a large, ver-tical wheel with coarse serrations orblades on the surface against whichthe cassava root is held in order to cutoff suitably sized pieces ready fordrying. This is a simple machine, of-ten locally made, which can be oper-ated by hand, pedal or motor.

Machines are also made for gariproduction. The crop is washed,peeled, grated, fermented, pressed toremove water, roasted, sieved andpackaged. A range of simple tools andequipment can multiply output con-siderably. Soil particles are washedoff in concrete tanks with runningwater. The roots are still cleaned byhand, even at quite large factoryscale. Attention should always bepaid to good seating, correct work-table heights and ensuring regularsupply and removal of the peeledroots.

The knife used to peel the rootsshould be sharp and of mediumlength with a good handle, sturdyenough to withstand the constanttwisting necessary to lever off thethick peel. The peeled roots can bewashed again, in order to remove anysoiling from peeling, although this isnot always done. The peeled roots can

be grated, using one of a range oftechniques that yield a good-qualitymash. These include the common mo-tor-driven hammer mill, locally madedrum graters or even manual graters.The resulting mash is left to fermentfor three to five days in non-corrod-ing containers such as polypropylenesacks, fibreglass drums, wooden box-es or stainless steel tanks; the choiceaffects the investment cost signifi-cantly, although the final product isnot so different.

The mash is then pressed to re-move the water. At village level, thiscan be done inexpensively with a

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FIGURE 14 Locally made cassava graterin Nigeria.

simple lever system of ropes andwooden beams, or with a more ele-gant screw or hydraulic press. Thelatter are usually based on lorry jacksand are therefore readily availableand cheap to buy. The cassava mashthat comes from the pressing stage isin the form of a cake, which has about50 percent moisture content andneeds to be broken up. Screens, sticksor simple scrapers can be used to dothis before it is placed in a roastingpan for preparing and drying the gari.In this process, the starch gelatinizesinto a hard, dry powder, which can bestored for up to a year.

Roasting can be done in a smallbowl or pan for domestic use, butlarger bowls are easily managed. Atvillage scale, large flat pans 2-3 mlong can be mounted on concreteblocks over a fire, which creates alarge, easily managed gari processor.The drying can be done in the samelarge pan by raking the powder to acooler part of the pan. These large flatpans can be used to produce up to500 kg of gari per day.

■ Cashew shellersA cashew nut crop is high in valueand lends itself to village-scale oper-ation, although there are some con-straints in processing rates. In India,most of the manual processing mar-ket is controlled. The skill and speedof the Indian processors and the lowcost of labour make it a difficult mar-ket to break into; some nuts grown inAfrica are exported raw to India forshelling. Cashew nuts are thick-shelled and contain a rather nasty,sticky liquid that is itself of some val-ue. There are small manual tools fordecorticating the nuts. After roastingin the shell liquid, the nuts can becracked open. Small mallets are com-monly used and can be operated atthe rate of about 10 nuts per minute.About 75 percent of the nuts will re-main whole, which makes them morevaluable than the broken nuts. In ad-dition to the mallet method, tools

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FIGURE 15 Large, flatbed gari-makingmachine in village production in Nigeria.

have been developed that feed thenuts into a chain system, where theyare clamped and a specially designedknife cuts and twists the shell off thekernel; other options exist but are notyet commercially available. Cashewnuts offer the opportunity to intro-duce a valuable cash crop at village

level with very little investment. Thesupply of raw cashew nuts can besomewhat unreliable, which wouldnot affect a village greatly, but a badcrop could spell the end of a factorythat depends on sophisticated auto-matic equipment and must pay a reg-ular labour force.

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Some supporting features should bein place before a new technology isadopted. Adequate supply of raw ma-terial, for example, is essential andprobably represents the most frequentsource of failure of village enterpris-es. These features and technologiesare listed below and then discussedindividually:• machinery sales office or dealership; • rural machine-repair shops; • training and skills acquisition;• structures;

• water;• packaging materials;• marketing;• transport;• disposal of waste.

■ Machinery sales office or dealershipMany machinery companies have on-ly one office in a country, and it maybe difficult for a potential buyer tomake a trip there or even to find it.Buyers are often not clear about whatthey require in the way of a machine.

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Supporting technologies requiredfor village processing

FIGURE 16 Rural workshop in Nigeria making cassava graters.

It is up to the company to market itsmachines properly, to set up publicdemonstrations and field days andpublish posters. A buyer who has a lo-cal sales office is fortunate indeed,because advice, training and mainte-nance support can be given.

■ Rural machine-repair shopsMost machines need maintenance atregular intervals, which can be pro-vided most easily by local machineshops. If the dealer who sold the ma-chine is nearby, maintenance can beprovided from that source. Spareparts will inevitably be needed. Main-tenance needs can range from a sim-ple weld to a new screen for a ham-mer mill or a rotor for a rice mill.Many components have to be import-ed, such as belts, bearings, chains andengine parts. Owners can make sim-ple replacements, but ordering ofparts and machining activities are theresponsibility of the shop. Easy ac-cess to this facility is very usefulthough not essential and may only beneeded once a year. These shops tendto grow up where they are needed.

■ Training and skills acquisitionTraining is vital for the success of vil-lage enterprises. An owner or manag-er has to have a basic understandingof the business aspects as well as thetechnical implications. These are notnatural skills, and they can be diffi-

cult to learn. Advice on such aspectsas bookkeeping, future planning andpayback periods is necessary to builda secure business with a good chanceof success. The extension service inmost countries is well positioned toprovide these services.

Practical techniques and skills aremore easily learned. Sales officesshould be able to offer all the advicethat is needed. Maintenance sched-ules, likely running costs and all otherimplications should be made veryclear. Advice can also come from aidagencies, missionaries and govern-ments.

■ StructuresMany small enterprises need at least aroof, if not a fully enclosed building.Most engines, for example, are de-signed to operate under cover. Tropi-cal storms can cause damage, so en-gines should be mounted firmly andlevel on a concrete base. The roof canbe made from local materials andshould protect both operator and ma-chine. Hand-operated equipment canof course be used wherever it is con-venient; a special place for storage isall that is required. Dryers, threshers,cookers and roasters are often set upwith a roof but without walls, allow-ing fumes and smoke to escape andletting the process continue even ifthere is rain. Rice mills, hammermills and oil extractors are usually

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kept in locked buildings because ofthe need to protect valuable itemssuch as bowls, sacks, tools, spareparts, raw material and finished prod-ucts. Materials used for the buildingdepend on the locality. Concreteblocks are the best choice if they areavailable, but in some villages awooden or mud structure with a roofof banana leaves or palm branchesmay be the best option. If no concreteis available, the machine should beprovided with a steel-bed frame andlevelled as accurately as possible.

■ WaterMany processes depend on potablewater, especially those that entail

washing root crops and fruit withfield dirt on them. If a well is nearby,then this problem is solved and the lo-cation of the process may be deter-mined by the location of the well.River water is not usually as clean aswell water, and if either well or riverwater is dirty, some form of filtrationis required. Normally, 1 m depth ofsand with a grain size of 0.3-0.8 mmwould provide an adequate filtrationbed, but further calculations and testswould have to be made to ensure thatsufficient water could be filtered. Asmall cassava washing plant, for ex-ample, may need up to 4m3 of waterper day, which calls for 4m2 of sandbed with 4m3 of sand and a suitable

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FIGURE 17 Galvanized-steel building for village hammer mill in Kenya.

holding tank. The rate of filtration de-pends on the physical properties ofthe sand and its natural filtration rate.Tanks and elevated support structureswould then need to be constructed,usually of galvanized steel or con-crete. In some villages, this type offacility might need an engine-pow-ered pump to provide the necessarywater, as hand operation might be toolaborious.

■ Packaging materialsPackaging materials depend on themarket. Local markets use traditionalpackaging materials such as woven

bags, baskets and wrapping leaves.For selling to larger markets, howev-er, or to markets in towns and cities,there may be a need for factory-madecartons, bags or plastic trays. Wrap-ping material can be of help, whethernatural leaves and twine or factory-made paper. Factory-made cartons al-so help in determining the packagesize. Consistency of price per unit ofweight helps give a buyer confidence.A well marketed product should bepackaged for protection and preserva-tion, and well presented, so that it willcommand a higher price. Some peo-ple will always prefer the local mar-ket type of presentation, even in thelargest cities, but with the growth ofshops and supermarkets, standardshave risen all over the world andgood marketing usually pays off.

Produce can be sold through entre-preneurs who own vehicles to takegoods to market and provide the appro-priate sacks and boxes. They are in agood position to reclaim containersfrom nearby towns and re-use them.When a farmer sells a product in a con-tainer, it is difficult to reclaim it or itmay be non-returnable. This reducesthe quality of container that the farmercan afford to lose, and so prices have tobe increased to cover the cost of pack-aging. Used containers such as bottlesfor oil, juice and other liquids, sacks forrice and flour and baskets and boxesfor dried spices are quite acceptable.

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FIGURE 18 Locally made basket for takingproduce to market in Thailand.

The main problems of returnable con-tainers are as follows.• Who should own them? • Is a deposit system workable? • How can theft be prevented? • How can a large number of bags or

boxes be identified?In the case of retail, the solution is

often clear: buyers can either bringtheir own containers or set up a de-posit system. A ready supply of sec-ond-hand or new containers can be aserious problem and needs to be ad-dressed at an early stage.

■ MarketingAny business depends on its markets.Unless there is an existing demand,

the market has to be created by per-suasion. If no market exists forpineapple juice, for example, cus-tomers have to be persuaded of itsvirtues. The easiest approach is tobuild from a small business with eachinvestment in new machinery fullyjustified by demand. In this case, oneshould simply make sure that themarket is not oversupplied, or theproducer will have to find new mar-kets, requiring expansion and travelto other towns or villages.

Most produce is traditionally soldat the nearest market. Larger urbanareas also attract street vendors andprovide an opportunity for sales toshops. Sales of processed goods are

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FIGURE 19 Returnable crates used for packaging produce to take to market in Thailand.

most successful, however, if a regularoutlet can be found. Informationspreads quickly by word of mouth inmost developing countries; if goodsare satisfactory, there is less of aproblem with marketing. A barter sys-tem may be necessary if a cash econ-omy has not developed; goods maybe exchanged in return for othergoods or services. In some cases, cus-tomers bring their raw produce to aservice machine and it is processed inreturn for a proportion of the goods.Maize or rice, for example, may bemilled in return for 10 percent of theinitial weight of the crop, and themilled product is returned in its origi-nal package. In some instances, cus-tomers receive their own crop backagain; in others, they simply receivethe appropriate weight of milled crop.

Marketing on a wider basis usuallyincludes a packaging strategy. Car-tons and bags may show the origin,weight and type of the contents. As ageneral principle, good packagingpromotes the goods and provides en-hanced protection and preservation.For sales in towns and cities this is agood approach, because the originalprocessor is likely to lose contactwith the final customer. If processorswish to build up a regular customerbase, they must identify their produceclearly.

The first rule for a successful busi-ness is to know the market. The best

product in the world will not sell if no-body knows about it. It is always easi-er to start a business with a productthat is in demand. Once that part of thebusiness is successful, other productscan be launched on the back of a goodreputation. A minimum level of busi-ness expertise is necessary for suc-cess, even at village level. At somestage, knowledge of office proce-dures, records, accounts and salesforecasting must be applied if thebusiness is to grow. Other implica-tions of a successful enterprise mustbe considered. If the introduction of alarge new hammer mill, for example,puts all the other smaller millers out ofbusiness, it not a success for the vil-lage. It is important to know the po-tential for immediate sales in the vil-lage as well as for wider sales outside.This situation can often be helped byentrepreneurs who buy local producewith no intention of further process-ing: they will simply transport it to abigger market for sale.

As a business grows, there is al-ways the opportunity for widespreadadvertising through outlets such as ra-dio, TV, roadside posters, portable ex-hibitions and field days. Extensionservices offer courses and help inthese matters in most countries.

The start-up and growth of any busi-ness requires investment and risk. Suc-cess is not guaranteed, and worst-casescenarios must be considered before

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taking the plunge. Thousands of smallprocessing plants and businesses thrivein developing countries, however, andmake significant contributions to thequality of village life. There is room formany thousands more.

■ TransportAs markets grow, products tend totravel farther and farther. Many farm-ers transport their produce to marketby bus. They will either stay at themarket until the produce is sold or gohome and return the next day. Thisapproach has severe limitations forperishable items but not for processedgoods, which do not suffer the same

losses that fresh fruits and vegetableswith poor packaging suffer on poorroads. Taxis, transporters and middle-men of various sorts can all play vitalroles. Local markets can act as gath-ering points where transporters willgather goods and take them by truckto main markets. In this case, thetransporter may be prepared to travelmore than 100 km, which would beout of the question for a small pro-ducer.

When farmers can justify buyingtheir own vehicles, however hum-ble and whether as sole owners orin a cooperative, it heralds an inde-pendence that is a new stage in

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FIGURE 20 Horse used for transporting produce to market in the Philippines.

their development. This assumesthe existence of roads that are pass-able for most of the year, althougheveryone will be aware of the dan-ger periods. The need for transporthas to come first, and the road willfollow. Businesses tend to grow upalong roads, so the presence of aroad encourages further develop-ment; the initial stimulus, however,is often the availability of agricul-tural items from a productive area.

Bicycles are popular in manycountries. Bags of produce can bestrapped to a bicycle or loaded into itstrailer, and distances about threetimes longer than with hand-carriedloads can be covered. This extendsthe market considerably. Most coun-tries have workshops that can servicebicycles, so this is an attractive op-tion, especially for low-volumeprocessed goods such as spices.

For fully preserved items such asspices, dried fruit and possibly jamsor high-valued items, animal trans-port may be satisfactory. Donkeys,oxen, camels and horses are all usedto pull trailers or carry saddlebags,depending on the size of the load.Trailers can have spoked wheels forlighter loads or old motor-vehiclewheels for heavier loads up to1 000 kg. Animals can cover dis-tances up to 25 km, and in some caseswill travel many days with a high-val-ue commodity.

■ Disposal of wasteIn developing countries, disposal ofwaste is not usually a high prioritycompared to obtaining sufficient foodand earning sufficient income. Wasteshould, however, be turned into a by-product whenever possible. Almostall agricultural waste material can beused in some way: peel, cores and anygreen waste from a plant used formaking juice, puree or pulp can usu-ally be fed to animals or composted tobe put back on the land; similarly,waste from cereal plants such as husk,bran or germ can be fed to animals.Rice husk is probably the most inedi-ble grain residue, although chickensand goats do pick over it. There areoccasionally special uses that can bemade of waste, such as selling the liq-uid that exudes from the shells ofcashew nuts. Even dirty washing wa-ter can often be re-used after filtrationto wash down floors and then as irri-gation water.

For drying processes, burningwaste as fuel is a practical way of en-hancing the value of materials thatmay require disposal. Excess com-bustible biomass can be used for fuel,as has been widely practised by large-scale sugar producers, who burn thecane residue known as bagasse to drysugar after it has been washed fromthe cane. In the same way, small-scalesugar expellers amass piles of man-gled cane that can be burnt to dry the

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sugar. Rice husk can be used to dryparboiled rice and even to fuel the ini-tial steaming. Residues from palm-oilpresses can be used to sterilize the in-coming bunches; sometimes the left-over nuts are burnt for sterilizing aswell. Prunings, trimmings and oldtrees from plantations can all be usedas a fuel for drying. In the earlysteam-powered oil mills, all theseresidues were used to heat the boilerof a steam engine that providedenough energy to drive the wholeplant.

Residues can be used in otherways. Through the process of anaero-bic digestion, most green organicmatter will form methane gas if thereis sufficient water available and thetemperature is more than about 22 oC.This is a very useful means of dispos-al and re-use of any inedible greenmatter, which yields up to 0.4m3 ofgas for 1 kg of dry solids. The greenwaste is dumped into a tank filledwith water to digest for up to three

weeks. The resulting methane gas canbe used for domestic cooking or evento power a diesel engine. The quantityneeded to drive an engine may be toomuch for a small enterprise, but itshoud be possible to produce enoughfor domestic cooking. A smallamount of equipment is needed, suchas a tank with a sealing lid and somepipe work. Domestic waste is also di-gestible in this manner. In Indiaalone, many thousands of small-scaledigesters are used.

If methane production is impossi-ble, any waste organic material cansimply be kept in a special area andturned over with a rake or fork everyfew days. It will turn into compostthat is useful as a soil additive andconditioner, returning nutrients to thefields. The heap should be kept in aloose but moist condition. Careshould be taken to avoid creating per-manent dumps for crop residues, be-cause they can attract flies, createodours and breed disease.

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Assiedu, J.J. 1989. Processing tropical crops: a technological approach. Lon-don, Macmillan.

CIAT. 1978. Cassava harvesting and processing. (Proceedings of workshopheld in Cali, Colombia, 24-28 April.)

Clarke, B. 1992. Tools for agriculture. In Crop Processing and storage: a buy-ers’ guide to appropriate equipment for small scale food production, Ch.6. London, ITDG.

FAO. 1977. Cassava processing, by M.R. Grace. FAO Plant and ProductionSeries No.3. Rome.

FAO. 1981. Rice milling equipment, by F. Garibaldi. Agricultural ServicesBulletin No. 22. Rome.

FAO. 1985. Prevention of post-harvest losses: a training manual. Rome.FAO. 1994a. Agricultural engineering in development: post-harvest opera-

tions and management of food grains, by M. De Lucia & D. Assenato.FAO Agricultural Bulletin No. 93. Rome.

FAO. 1994b. Grain storage techniques: evolution and trends for developingcountries, ed. D.L. Proctor. Rome.

FAO. 1995. Fruit and vegetable processing, by M. Enachescu Dauthy. FAOAgricultural Services Bulletin No. 119. Rome.

Fellows, P. & Axtell, B. 1993. Appropriate food packaging. Geneva, Interna-tional Labour Office.

Head, S.W., Swetman, A.A., Hammonds, T.W., Gordon, A., Southwell,K.H. & Harris, R.V. 1995. Small scale oil extraction. Chatham, UK,NRI.

Nazare, R. & Nalumansi, S. 1996. Processing vegetable oil. Harare, Agrotec.Potts, K.H. & Machel, K. 1995. The manual screw press. London, ITDG.WFP. 1983. Food storage manual. Rome.

Sources of Further InformationINPhO, an international network in post-harvest operations, available at:

www.fao.orgNatural Resaources Institute (NRI), Chatham, UK, available at: www.nri.org

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Further reading

Intermediate Technology Development group (ITDG), Rugby, UK, availableat: www.itdg.org

Central Food Technology Research Institute (CFTRI), Mysore, India, avail-able at: cftri.com/unu

International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, avail-able at: www.cgiar.org/iita

Australian Centre for International Agricultural Reseach (ACIAR), FernhillPark, Bruce, ACT 2617, Australia, available at: www.aciar.gov.au/

International Centre for Tropical Agriculture (CIAT), AA 6713, Cali, Colom-bia, available at: www.cgiar.org/

International Rice Research Institute (IRRI), DAPO Box 7777, Metro Manila,Philippines, available at: cgiar.org/irri

Centre de coopération internationale en recherche agronomique pour ledéveloppement (CIRAD), 34398 Montpellier, cedex 5, France, available at:www.cirad.fr

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High hopes for post-harvestTable of contentsAcknowledgmentsPrefaceForewordSome basic facts about village processingBenefits of using appropriate processingtechnologies for creating sustainable livelihoodsChoices and the factors that influence themMachinery choicesBusiness choicesCrop choices

Some factors that affect choicesHow to do it:equipment and methods for village operationGrain storageOil extractionRice millingMaize millingCrop cleanersCassava processing equipmentCashew shellers

Supporting technologies requiredfor village processingMachinery sales office or dealershipRural machine-repair shopsTraining and skills acquisitionStructuresWaterPackaging materialsMarketingTransportDisposal of waste

Further reading