University of Nigeria Virtual Library

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Author 1 OBANU, Zak A

Author 2

Author 3

Title Food and Production in Nigeria in the 21st Century: Issues on Food

Processing and Storage

Keywords Food, loss, preservation,

processing, industry, storage packaging, policy.

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Agricultural Science Publisher

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FOOD AND FIBRE PRODUCTION I N NIGERIA I N THE 2 Is' CENTURY:

ISSUES O N FOOD PROCESSING AND STORAGE.

PROF. ZAK A . OBANU, mni. I)€ PARTMENT O F F O O D SCIENCE A N D TECHNOLOGY

U N I V E R S I T Y O F N I G E R I A , NSUKKA. '

ABSTRACT

With the current stress on rural development emphasising provisions of infrastructural and municipal utilities, proliferation is envisaged of small- and medium- scale industries including food processing industries close to raw material sources. This is expected to lead to strong organisational links between raw material production and processing that is expected in many instances to integrate food processing industries and agriculture into agro-industrial complexes in 21" century Nigeria for obvious benefits. This paper has discussed the inherent perishability of the foods that form the raw materials of food processing industries as well as the quantitative and qualitative losscs before, during and after processing and/or storage with the attendant farin-gate or post-harvest technologies to reduce food losses. Food preservation and processing methods have also been discussed with their varied applications1combinations and diversity of products resulting from diverse food processing industries of varied complexity and scales of operation.

The performance of the food industry in 20Ih century Nigeria was examined with a forecast of greater proliferation of small- and medium- scale industries employing appropriate processing technologies and machines suited to local resources and skills. The practices and merits of food storage and packaging were reviewed and the need was highlighted for research and development of local storage and packaging materials and practices. The paper ended with ten policy implications and strategies to enhance food processing and food industries if Nigeria is to achieve national food security and generate adequate foreign exchange from food processing in the 2 Is' century to become self-sufficient and a world power as expected.

KEY WORDS

Food, loss, preservation, processing, industry, storage, packaging, policy.

lryT Introduction National food-anb-fibre production is~;ia&o-national survival and buoyancy. It is the vital tripod

stand of national-food security, agro-processil~g and agro-exports; and hence-national-self-reliance, employme& and foreign exchange generation. In all aspects and considerations the essential target of nationgfood-and-tibre security is the assurance of readily availabIe food and fibre suppIies in adequate

- levels of loss at all stages of the post-harvest system. d with plans for post-liarvest conservation techniques n to stabilise (i.e. render less perishable) the produce 1 - --?-:-..:.-- A!-:- A - - : A - - - L . - - ---A ------- :-- ---- *..-

quantities and quality within the purchasing power of even the poorest consumers all the year round - a target that hinges heavily on enhanced production, proce:;sing, storage and distribution.

The target of cheaply available food all the year round has till date been pursued emphatically and rsrgtably,through_breeding and better agrononic or husbandry practices and very recently through molecular engineering and-biotechnology with wry little or no concern for post-harvest loss$s,-handling, processing_and_storagel It is now recognised that massive production techniques and practices cannot, and- ~iill not, achieve all-year availability of food and 'ibre and that it is essential to conserve what is produced. Improved production practices with new crops, new varieties or breeds. etc. will strain the existine: food* handling capacity, creating possibilities for increased Thus food production increases should go hand-in-han A d incentives. This is where ago-processing conies i and facilitate its handling, availability and utility. While acrllevnlg ~ I I I S U W U G I ~ L U I I I ~ ~ , I O - ~ I U L C M I I ~ , C I C ~ L C ~

cniployment and raises the purchasing power of th? citizens to ensure their ability to obtain conveniently the food and fibre thus made cheaply available. For an integrated food production and food-processing, it is nccessary.!o strengthen-the-interdependence ard complementarity of agriculture and agro-processing industries. In particular agro-industries should gi /e increasing support to the development of agriculture, which in turn will provide it with raw materials. Indeed, desirable food-processing attributes need to be inculcated into all farm produce during breedin):, husbandry and harvest. Fluctuations in the supply of adequate agricultural raw materials to food-processing industries may be rectified by establishing closer organisational links between industry and agricu1:ure as is the case with 'Vegfru' tomato production and processing in Dandikowa, Gombe state. Such agrc-industrial'~omplexes with integration of food processing industries and agriculture would also provide industrial support f o ~ jment as in Vegfru where the industly provides farmers with improved tomato seeds a With greater rural industrialisation and location of industries close to sources of raw mi ntegrated symbiotic development of food production and food process ng is envisaged II I L I couru jy i u~ac t~a . Food processing issues of such desirable integrated food production and food processing form the focus of this discourse.

- r agricultural develor nd agronomic inputs. aterials more of this il ;.. I l S I -.-."* ....., XI;--..:

Food Perishabilitv and Losses Far3produce of both plant and animal origin are perishable -- to varying degrees. Cereal grains and

grain legumes with relatively low moisture contents at harvest are less perishable than roots and tubers, fruits and vegetables. meat, fish, milk and egg all of which are naturally highly perishable. The varvinz intrinsic level of perishability af our farm produce are increised in N sunshine and temperature, too high or tool low relative h~ - aggravated by prevalent pop_handling and-storage practices

- - . . r - igcria by our tropical climate with high ambient umidity, etc.. This high perishability is further ;, -. filthy -. environment, insanitary habits, illiteracy +A -A~L-..:--l ;-:..-, L*--..-- -C +LA:- ,.ha-- --A

- and general-poverty, Perishables are much more suxeptible LU I l l c ; u l a l l l L a l Illjury vcLaux "1 I I IGI I X I ~ ~ E : ~ I I U - --- s&cture, soft texture and high moisture content, md the need for more careful handling. Injuries lead to

- .

increased physiological contaminant activities enhaicing perishability. Physiological losses consist of natural losses due to endogenous respiration, moisture loss from wilting or transpiration, and abnormal losses arising from exposure to heat, cold or otherwise unsuitab e environmental conditions. Possibly the greatest single cause of post-harvest loss in perishable produce . s decay or rot caused by microbial contaminants. This usually occurs from initial infection by one or more specific pathogens, which may then be followed by secondary infection by a broad spectrum of biodeteriogens saprophytic on the dead or moribund tissue remaining from the primary attack (Coursey, 1974). Attacks-by rodents-and stored-product insects also lead to large losses especially in durables like grains. ~ F ~ a b l e 1-shows p o s t - h a r d 10-sses claim significant proportions, sometimes more than half, of out total produce. Table 1 Estimnterl post-f~awesi losses {percciil) in Nigeria Roots/Tubers Cassava 1 10-25 Yams 1 10-60 Potatoes 1 5-40 Carrot 1 44

I I

Adapted from "Post-Harvest Food Losses in Develo ling Countries", National Academy of Sciences, Washington, D. C., 1978 with moclifications by present author.

Vegetables Peppers 1 20-50 Tomatoes 1 20-50 Onion 1 16-25 Leafy Vcg. 1 50-70 Lettuce 1 62

Fruits Plantaii 1 35-70 Banana 1 20-80 Paw-paw 40-80 Citrus 1 20-70 Apples 1 14

Grains Rice 1, 6-24 Maize 1 5-70 Sorghum ] 0-37 Millet ] 0.1-0.2 Legumes 1 1-6

Animal Products Meat ! 10-40 Fish ! 15-40 Egg ! 10-25 Milk 20-50

I I

FsherJosses.occur during food processing for diverse reasons at each of the five operational stages as shown in Table 2 (Chou and Harmon, 1979):Bsides physical losses during post-harvest handling and processing, compositional interactions and changes x c u r that affect quality and shelf-life. These qualitative changes may alter the processing characteristics 2nd nutritive value of the farm produce. Poor storage conditions with high temperature and relative humidity favour mould growth that produces toxic compounds e.g. aflatoxin and other mycotoxins, and predispose the produce to infestation especially by stored-product pests. Such staple foods with high moisture level; suffer a decrease in quality because nf the Maillard reaction.

C. ;!rial r s s i n g a a

Excessive trimminu, eeling, cuttino, washino Inefficient use of b - roducr:, and waste Excessive water use -

( 4. 1 Excessive heat inputs

( 5 . 1 Inefficient separation, mixing, etc.

1 6 . : Excessive delays in processil~g 1 7. ! Over-nackaning

: (i.e. staling)

-

lent

E. I Final use I 1. ! Imoro~er storage

1 5 . 1 Handling losses and bruising, Source: Chou, M. & Harmon, D. R. (eds.) (1979). Critical Food Issues of the Eighties, pp. 183-1 84,

Pergamon Press, New York. i I

Poor storage~of~common~beans(cowpea), for example, will increase the hard-to-cook problem which _.---

- also decreases the nutritional quality (digertibility) of legume foods as Table 3 shows (Bressani. 1983). --- - -

60 * " Recentlv harvested beans

Table 3 E ect o stora e and rocming on the digestibiliiy of hard-to-cook beans

Adapred.fiorn Ricardo Bressani (1983). Food and Nurition Bull. Vol. 5 No. 1

Cookin Time (Min.)

P~st~harves t losses are .significantly redua:dby timely adequate agronomichusbandry practices . - including harvest. proper location of processing pla~~s-efficient co-ordinationof fardprocessing activities, adequate warehouse/silo capacity, management, qua ity control a n d distributionlmarketing netwoik. Where industrial infiastructural facilities like roads, water and electricity are adequate, agro-industries should best be located close to the raw-material source to minin~ise losses, storage and transportation and to maximise co-ordination between producers (farmers) and processors. Rural agro-industrial development is therefore advocated pari pasu with overall rural development, as part and parcel of the 'poverty alleviation programme' of the present and future governments.

Apparent Digestibility (%)

Farm-gatepost-harvest Technolopies to Reduce Food Losses The time of harvesting is important for the slorage quality. If maize, for example, is harvested when

just ripe, it contains too much moisture for safe stora:e. The crop is usually left standing in the field to dry. Depending on the variety and climatic conditions, th s may result in losses due to mould growth and insect attack. Losses due to rodents and birds can also iwrease in this way. Traditional threshing and shelling operations may not separate all of the grain from the plant. Some methods do not remove impurities effectively and others may damage or crack the kernel:. Damaged grains are more susceptible to insect attack during storage. If grain is processed in the householc these problems can be reduced by additional manual cleaning. With rncchanised threshing and shelling th: losses can only be reduced if suitable equipment is used in the correct way.

Drvinggroblems-often occur when crops h w e to be harvested during the wet season. Artificial . -- drying is necessary in such cases. It is however, a very sensitive operation which requires experience. Too rapid drying and over-drying may cause cracks in .he kernel surface which can cause breakage during transport or dehulling. Under-drying may cause microbial spoilage. Selection of the right procedure is therefore vely important. There are b&c_hemical - and b ologica! causes for losses during storage. Biochemml changes are for instance:

Production of water, heat and CO? by respiration;

L.4 1 Oxidation, causing rancidity. The biological causes may be:

i Micro-organisms, especially hngi which can p rod~ce mycotoxins; Insects and mites that not only eat considerable amounts of food but also cause spoilage because of water migration (heat 60111 the insects causes water to evaporate and condense somewhere else in the storage); Rodents and birds.

On the fary~radi t ional practices are not a h a y s adequate for storing new varieties. High yielding maize varieties for instance, are more susceptible to inject, rodent and bird attack because the husk does not completely enclose the grain as it does with traditional varieties.

From the moment f w d is harvested. until it is eaten, rhe best handling techniques that c@e possibly applied ought to be used to ensure that all produced reach the consumer unimpaired in both organoleptic and nutritional quality. To preserve as much as possible the original quantity and quality for as long as possible is the objective of sto ms. This requires a thorough understanding of the food-path as in Fig. I from harve is, storage. and pre-processing to processing and product storage up to consumption. L w r u l i l u r r s w nt,rlvluca at one starre of the food-path can have important influences on the losses that appear in consumption in Nigeria is substantially increasing the ~ o v u supply aval ic lu lc IIUII CXISL I I I~ I ~ ; W U I L ~ ; ~ LU d ~ r ~ ~ t ; v t . IIIUUSLIMI I ~ W - I I I ~ ~ L C I I ~ I

supply and national food security. Such post-harvest technologies waste in packaging and transportation and reduce lcsses that r security control. Waste resulting from mechanical harvesting I

% 48.2 55.7

ring and processing syste :st through farm operatior P,,a:&:,,, ,, ,,+:..:*:~r . ,

other stages. Atgresent, 3t least one-third of all food produced for human lost annually.~~~cknologies that reduce the extent of these losses can help in r - - A -. --I- :l-Ll- c-- --.:-.:-- ----.--- "- *- : - A ..-.- :..I --.-. .--*-..:-I

technologies or by gleaning the produce left by mechanical harvesting. Waste resulting from mechanical/physical injuries can be mlnimised by using the correct tool correctly and carefully. Bruising and spoilage during transportation can be reduced by t d k packing at the field for short distance delivery to nearby stores or processors. Siting of processing p l a ~ t s in rural areas at local production points is a plausible strategy for reducing storage and transit food losses.

__.-- .-

I~ Well-conceived programmes, on the other hand. may not only_save_food but also help to provide jobs and distribute income more widely (thus increaing food purchasing well as-saving - - - + - foreign - e ~ c h a n g & ~ reducing food imports. 1n-such cases, tI e~qcial-benefits-can often be of greater weight than the investment in loss reduction activities. Food losses are related to social phenomena, and ways should be found to incorporate government concern for a coun:ry's food supply with the socio-cultural implications of food loss and food loss prevention. Because food conservation bears similarities to other types of intervention into rural practices, the problems and swcesses of rural health delivery, agricultural extension, and other community development interventions at the village Tevel should be studied by those *who plan for food loss reduction. The need to integrate new practices and revised technologies into village economies call for a better understanding of tradi ional practices and, generally, of the conditions that faciiitate or hinder corrective measures. Thus, t h e ~ e is a need for more research into the links among economic and cultural practices and food losses. Mole understanding is needed of the effects of government financial policies (subsidies, price controls) on post- larvest losses and incentives to reduce losses. Specific case studies are also needed to illuminate village-level problems, such as the impact of subsidies on the motivation to adopt new or changed technology. There is a particular need for data on the costs of increasing the availability of food commodities through loss reduction. Such economic evaluation is essential for comparing food loss reduction strategies wit11 other types of interventions as an aid to more effective decision making and planning of development programmes.

Food Preservation and Processing In the food industry processing may be defir ed as any alteration in properties intentionally induced

by physical, chemical or biological means. Thus % m y vary from a very mild heatTr&ttment which'has only a slight effect on the nature of the food, as in the pasteurisation of milk, to such major types of the conversion of wheat into bread, cassava into gari or fruits into fer nented beverages. Preservation is often used as a more restrictive term than processing to describe conservz tion operations that leave the nature of the foodstuff intact such as drying of cereal grains and legume grains. Modem food preservation and processing not only permit the sale of most foods all year round (i.e. in as well as out of season) but also enable adequate supply of foods to be made available in densely populatel regions (cities and towns) at an economical price regardless of ecological and climatic controls over production.

Just as there are fivepathways for-food det:rioration/spoilage (i.e. microbes, enzymes, chemical, animaliinsect, and mechanical) so also the re arc five-methods- for-food preservation, namely - heavrefiigeration, drying, chemical, mechanical and biological - which are usually classified as physical, chemical or biological as in Table 4. These methods are reducible to three scientific principles. First is killing by heat or ionising radiation as in canning, pasteurisation and irradiation and the elimination of renewed contamination by enclosing the food in hermetically seded packages. The second principle is the suppression of microbial growth through low temperatures as in rtfrigeration and freezing or chemical compounds as in salting, smoking, acidulation and use of preservatives and antioxidants. Closely related are various fermentation methods, inducing acidity changes (by acetic or lactic acid) and formation of preservative metabolites. The third principle is the removal of vater by dehydration, evaporation and concentration. Combinations of these methods are commonly used in Food industries. Deteriorative biochemical chan, ves are by all methods suppressed or so effectively subdued t lat no substatitial deterioration takes place within the time limit set for regular marketing.

Thus foodstuffs are preserved for transit from producer to consumer smoothing out irregularities in production to ensure that local or seasonal surpluses a-e not wasted and that both producers and consumers enjoy satiating economic returns. Besides, edible portims of an agricultural produce are separated from the inedible portions so also are nutritious portions sepsrated from poisonous portions. In addition to these extraction measures are transformation and compositing measures, all of which help diversification of products to meet individual consumer tastes and choices. To achieve the goals of food processing, food industries go beyond preservation to processing activiti~s as shown in Table5 to: (a) extract_fiom-agricultural commodities food and nutrients such as flour, starch and sugar that are not readily &ailable in the naturally harvested products; (b) transform.or-conven agrict~ltural products into other products more suitable for human consumption (e.g. bread from wheat, gari from cassava, etc.) or relished by the consumer (e.g. ready- made foods, wine and bread); and (c ) ernsure-detoxification and~wholesorneness~of all foods and food products.

Table 4 ~MerImds of Food Preservatioi~ n i~d Processing PrincipIe ( Method 1 Typical products - - - .

Sterilising

Physical

Smoking Refrigeration

Heat adding

Drying

I Freeze-drying Chilline

Pastelirisation Boiling

Irradiation

Pasteurised milk Cooked ham

Chemical

Salting

Smokin 7

Sterilised mllk, most canned meats, fruits, vegetables, ready-made foods Meat. fish cheese Perishable fruits and vegetables, milk, meat, seafood, perishable manufactured foods All foods

- - -

Sweetened condensed milk, evaporated milk, Milk solids, soups, vegetables, ready-made dishes -

Slvimps, vegetables All foods

Freezing I Most foods and evaporated dishes Millino I Cereals Pressing Vegetable oils

- 1 I

Solvents ( Fish and meat flour Ultraviolet I Water Electronic bombitrdment 1 Not established (including gamma rays) 1 1 Prickling (vinegar) ( Many pickled vegetables 1 Dry-salting ( Vegetables, fish, meat Brining I Smoke infiltration 1 Meat, fish, cheese Smoke concentrates

Preservatives Bleaching

Adap!ed,~om: Georg Borgstrom (1968). Principles of Food Science Vol. I., p. 104. The Macmillan Co., New York

Alcoholic fermentation Flavour-producing

Fermentation

Depending on the degree of twhnical processing, final food products may be distinguished as follows: ,%,~cv (i) P~eservedjioods: items that are little changed in t ie manufacture, the main operation being preservation

e.g. canned, frozen and dehydrated foods. (ii) Mri~zifjiicturcrl foods: Products in which the raw material usua!ly loses its original individuality as for

jams and mammalades from fruits or sausage fron meal. Preservation in these cases is commonly the result of combining two or more of the methods s! mvn in Tables 4 and 5.

(iii) Primnry derivatives or pare produc&: Components obtained from the raw food through far-reaching purification e.g. flour from cereals, starch from maize and cassava. sugar from sugar-cane, oil from nuts/oilseeds and fats fiom fish and animals.

(iv) Secoirrlnry derivtrtives: e.g. fats hardened by hydrogenation involving more elaborate chemical engineering.

(v) syiitlreticjooils: Made through microbial or chemisal synthesis e.g. vitamins.

Benzoic acid, sulphur dioxide Sulphur dioxide Chlorine dioxide

Beers, wines, spirits, indigenous beverages Ripened cream, butter, sausages, cheese

Fruit juices, sugar syrups, sausages Fruits Flour

Biological Acid fermentation Lactic acid

Acetic acid Citric acid

Cheese, cultured milks, cream Vinegar

Fig I Flow sheer offoorlprrrl~ for cererrls cmdprrlses

harvesting

i 1

.eshi& (dry corn) 1

,- slora::e (farm storage) I

p;lmi~ry processing 1 [ ( c l e a n i n z . grad ng, tempering, soaking,

I perboiling,deha~ ling, pounding, grinding, winnowing, d ying,sieving. milling.)

U s e ~ n d a $ ~ r o c e s s i n ~ (blending, formi~g, cutting, extruding, cooking, baking frying, also quality control and pack aging r-

(recipe de~elopmcnt, prcduct testing, consumer acccptancc)

Source: Bruinsrna, D.H, Witsenburg.W.W & Wurdmmn, \;1.(1983). Selection ofTechnology For F w d Processing in Developing Countries. Page 78. Pudoc. Wagcningen

7 r

,kq!

These fweign excess-capacity plants and pwesses, produced in developed countrm where labour costs are high and capital costs low, have caused great-drain of-foreignexchange, tnani~eune_mplo~,yment,

-- de-stabilised - - - our ~ ~ c ~ ~ ~ c u l t u r a l affections and dra ned-our-economy-through exploitation-and untenable developmenfpla&. It has led to-aJagging behind i f large numbers of the populace (especially in rural areas) c a u s & & ~ o ~ e t a ~ m ~ ~ l ~ a n d - i n r f a b i l i ~ . I s spite of many fi-ustrating problems, the madern large scale t Z n o ~ o g i e s and plants have remained tre popuLs choice in Nigeria unrii today. Several reasons are responsible for the persisting choice of relatively ca~i ta l intensive food industries; most important of which derive fi-on1 the macro-economic measures proposed by governments to stimulate industrial actions:

J + Offering finance and interest rates below thos: in the open market stimulates inveshnent in capital

mtensive rndushy at the expense of labour in t enhe industry. Equally favourable credit facilities are not usually available for small labour-intensive inr ustries in a form adapted to their specific needs and repayment capacity.

+ Foreign companies are invited to settle and may I E offered incentives and tax concessions. + I'oreigners bring in and install for economic gains their large scale plants and technologies that are

fading out or obsolete. + Contracting agencies making feasibility studies znd managing projects do not have an open mind to the

small-scale labour-intensive alternative options. + There are only few low-cost labour intensive tecknologies that are presently competitive. + Research and development efforts are directed principally toward capital ~ntensive technologies rather %m

the more socially suitable low-cost labour - inte~isive technologies. It 1s certain that to realise a change from capital intensive food industries to low-cost i~~dr~stries

changes in government policies and development strategies are required. No doubt, any decentralisation of food-processing industries to make them viable and to serve social objectives wdl call for stmctural changes emphasising rural development and industrialisatio~i. This will necessitate policy changes and people- oriented programmes that stress the economic upliftment of the masses of Nigerians that dominate our villages and sub-urban locations, Small and Medium Scale Food Industries: The serious lagging behind of the low-income groups in Nigeria is partly the result of the large-scale capital-intensive industrial approach which created inequalities in development and partly of the rapid increase in populi tion which is not matched by an equally rapid increase in food production and supply. In the family latour situation prevalent in Nigeria, the large scale technologies are usually not suited to improving local 'ood supply and making more efficient use of the local raw materials and labour. Conversely, accelerated devdopment and industrialisat~on of labour-saving devices for agriculture, food storage and food processing at village or home level, which is the basis of small and medium scale industries employing small-scale mechanised processes, would contribute greatly to poveity alleviation, upliftment of the socio-economic status an j quality of life of the masses of Nigerians domicile in our rural areas. At the village level, good opportunities exist for using local raw material, labour and artisan skill In food loss-reduction activities; all of whicl- are cheap and acknowledged with relatively low opportunity cost. Use of these rural resources, moreover, provide direct social benefits by generating elnployrnent and distr~buting incame, in addition to re~lucing f w d losses for the benefit of poor families and consumers. Increased food availability in the sector c tn also provide the poorest farmers and farm women with access to, and perhaps integration into the urbar and export markets. Thus, a persuasive case can be made h a t careful social cost-benefit analysis will sup~or t an increased emphasis on diversified proliferation of small and medium scale food industries as the focal thrust of our poverty alleviation nnd rural transformation programmes.

The small and medium scale food-processint; sector in Nigeria has been regrettably neglected in terms of encouragement, infrastructural and financial s13pport as well as in terms of research and development of processes and ~nachines vital for its operations. This sector is generally made up of family or one-man run

i businesses, which have evolved over the years, with little access to capital and technical services. It is, Ijowever, the main source of low-cost traditional food products, often based on local raw materials, which are importc~nt components of the meal of local consumers and is an important source of employment and mcome.

The small-scale industries sub-sector of the Nrgerian economy provides a veritable platform for the socio-economic development of the country. It is, th:refore, vital that efforts be made to strengthen this

, sector to promote self-reliance through development o f local industry with local skills to meel unique Eocal

needs and market conditions so as to ensure ready wailability of the indigenous processed foods. he resulting solid base of indigenous small and med~um icale industry could also lead to the development of home-grown indigenous larger scale industries that will be more appropriate and more suitable than imported large scale technologies and plants. This should be the progressive trend of food processing and food - -. . 6 I

: I ; i ; ; !I . I ) I I I - .. , t e f ' l v F C l h r r l r 5 LtHLI i U U U

industry in 21 century Nigeria.

Table 5 Main Cutcgories of Food Processi~rg Tech~tology

a. Slightly perishable crops adequate storage (stable for more than 7 days) egg processed e.g.: some root crops (powdered albumin)

egg cereals pulses

Extraction single component

nuts b. Moderately perishable crops

(stable up to 7 days) e.g.: fruits

vegetables some root crops

c. Highly perishable crops (Stable Car less than 1 day) e g.: miik

PU I t r ~ sea foods

Sugar milling (beet sugar) oil seeds dates (for sugar)

~ickling salting smoking fermentation drying canning cooling

(freezing) cured meet salting ‘%'I% canning cooling (freezing)

butter fish oil

Extraction edible portion

Cashew nuts milling of grains and pulses treatment starchy tubers, roots tea processing coffee processing

Transformation

bakery fermented soy products breweriesldistillerim extruded cereals gari

"m"I;-,. ,,""" .- : . . 1 . b W U I ~ I I I ~ ~ I L I ~

trimming jams cutting jellies de-stoning fruit juices vegetable juice

slaughtering chcese cutting yoghurt fish meal ghee

butter sausages

products composite flours :x~ruded products :e.g. pastas)

infant milk foods

malted milk

Source: Bruinsma, D. H, Witsenburg, W. W. & Wardemann, W., (1483). Selection of Technology for Fwd Processing in Developing Countries. Page 32 A publication of the International Course in Food Science and Nutrition (ICFSN), Pudoc, Wageningen.

Other compelling reasons'for emphasising the development of the sub-sector include: a. better utilisation of simpler production techniques, adapted to local resources and conditions; b, greater use of local raw materials; c. suitability for satisfying more quickly the demand for consumer goods and flexibility of production; d. the use of less costly infrastructures and technologies

1 e. greater participation, in the economy by nationals I f. relatively simple to manage; I g. small-scale industries lend themselves in particular to industrialisation efforts that favour

decentralisation and rural development;

J h accelerating overall industrial self-sufficiency especially in the rural areas, to arrest the rural migration by the young and able-bodied to urban centres looking for greener pastures.

Food Storage And Packaging Food Storage: The logistics of farm produce supply to food processing industries and the marketing of the industrial products necessitate food storage before and after processing as shown in the food path (Fig. 1). The objectives of providing suitable storage facilities are: (a) Conservation of food by minimising qualitative and quantitative post-harvest losses; (b) attainment of self-sufficiency in food requirements; (c) regulation and possibly replacement of private intermediaries in procurements, handling, storage and

distribution; (d) by the establishment of public-sector storage facilities to achieve -

i. stabilisation of consumer prices and the protection of the interest of low-income groups; ii. assurance of reasonable prices to producers as an incentive for increased production (price support); iii. maintenance of stocks as a buffer against periodic and unforeseen shortages and consequent high

prices; (e) by research and development to achieve -

i , an increased use of local materials in building storage facilities of different scales and designs suited for different purposes, especially at the farm and village levels;

ii. development or adaptation of technologies that farmers can afford to install and use; (f) generation of increased employment opportunities in the building of low-cost structures at the farm and

village levels. In Nigeria, as in most developing countries, most raw and processed foods, like grains and dried

products are handled, transported and stored in bags. Accordingly, the entire marketing and storage system inhibits the adoption of the advanced technologies of bulk storage such as grain storage in silos and bins in which grains can be stored up to four or five years. Nevertheless, low-cost improvements to traditional storage systems may be appropriate at the farm and village levels. An effective extension service to assist farmers in improving their traditional storage techniques and also in building community storage facilities is necessary. Such an extension service should include: (a) financial support to farmers and communities; (b) dissemination of information on alternative storage techniques; (c ) provision of designs and guidance in construction; and (d) subsidies to meet the requirements of the less affluent sections of the community. Nevertheless, in general terms, the choice and appropriateness of any storage technique depend upon how much is to be stored and for how long. The nature of the marketing and distribution systems, including the availability and mode of transport have a bearing on the choice of storage in terms of quantity and duration of storage.

Packaging: Present-day food packages protect their contents during storage, before sale and in the home, from contamination by dirt and other foreign material; infestation by insects, rodents, and micro- organisms; and loss or gain of moisture. They are fi-equently designed to shield the food from deterioration resulting from contact with air, light, heat and contamination gases. They may serve as containers in which the food is processed and as containers in which the food is heated for serving. These attributes of food packages have contributed to the development and marketing of a whole new array of food products. Highly processed foods - the convenience foods such as ready-to-serve products, prepared dinners, mixes, and the like - may have peculiar and specific requirements that only special package formulations can meet. Only through the advent of new types of packaging materials was it feasible to meet these many new far-reaching demands of a complex technically dominated society.

The packaging of a food product consequently is much more than the mere enclosing of a food in a container. It is a many-faceted problem comprising such factors as (1) specific product protection, (2) package durability, (3) appearance, (4) suitability to retail display, and ( 5 ) consumer appeal. In the retailing of food, packaging not only facilitates handling but has introduced accurate routine weighing and portion control. Retail packaging of food has therefore been instrumental in making feasible one of the most

profound revolutions in food selling by allowing the weighing operations to be transferred from the stores to the manufacturing industry. This relieved the eitire food trade of an otherwise cumbersome operation. Weighing thereby became more accurate and more reliable, chiefly through the introduction of mechanical aids. Standard measures and sizes became rout ne, facilitating all phases of selling besides making the products far more hygienic, with less risk of handling contamination.

Furthermore, packaging paved the wa} for self-serving and provided facilities for on-the-spot advertising. Packaging has become indispensable to almost all handling in transportation and distribution. Rice packaged on an assembly line where cleanliness is scrupulously maintained is surely preferable to the rice in the old-fashioned paper or jute bag weighei out by the trader. Cheese packaged at the factory has not been breathed on. sneezed on, or bent over by other customers. Packaged spices are fresher and more aromatic than when sold exposed in the market. Packaging also enters into the preparation and serving of food. Several packages carry measurement indications to ailow the removal of defined quantities. Many foods, such as sugar, milk, jam and mustard, are served on the table both in homes and institutions in their packages, thereby reducing the need of serving tat leware and eliminating dish-washing.

lnnovations in food packaging show no tendency to taper off - almost the reverse. This is basically explained by the wealth of new materials and :ompetitive job of packaging. New types are constantly reaching the marketing stage. Some novelties particularly worth watching are ( I ) transparent, non-sticking, vacuum-formed meat trays of polystyrene; (2) tnc rrnostable cook-in pouches that withstand heat processing in conventional retorts; (3) new protective coating for glass, not removable by water and withstanding boiling and autoclaving; (4) lighter and thinner tin plate; and (5) steel foils.

Policv implications and Strategies for Enhancgi Food Pmcessine The discourse so far calls for the following vital policy needs and strategies by governments,

entrepreneurs and researchers to enhance food processing in 2 1" century Nigeria for the assurance of national food security and self-sufficiency, import-substitution and exports, rural transformation and poverty alleviation or even elimination, economic self-rcliance and true political independence with international respect. + For an integrated development of agricultural raw materials production and food-processing activities, it

is necessary to strengthen the interdepende'lce and complementarity of industry and agriculture. In particular, industry should give increasing $upport to the development of agriculture, which in turn would provide it with raw materials.

+ The priority areas that need attention include maintenance or even reduction of the cost of the products by increasing the efficiency of production ;o as to bring the products within reach of the masses; investigation of the nutritional qualities of focd products so as to promote their consumption and thereby correct protein and caloric deficiencies of tie poorest sections of the population; and generation of employment.

+ Basic infrastructural requirements such as transport, credit, marketing, warehousing and institutional arrangements are needed to facilitate the deielopinent of the food-processing industries. Nigeria, like other developing countries lack adequate technical skiils, equipment and management abilities. [n the export of processed products, inadequate information on the export markets, lack of quality control, and tariff barriers have proved to be serious conshaints on the industry.

+ Energy needs of the food-processing Industr~es should receive specific attention. Some industries like bakeries, sugar production and preservation c f fruits and vegetables are large consumers of energy even in small-scale operations. Considerable rese;irch work is needed to improve the design of equipment with a view of reducing the energy consumptiw of these industries. Some methods of conserving energy which need immediate attention include the lagging of pipes and vessels to prevent heat loss from radiation and conduction: better methods of heat transfer; and more efficient plant layout to reduce the distances travelled by hot liquids and gascs. In addition to the energy directly consumed in the production process, attention would also need to be given to improve the energy eMiciency of packaging, most notably in canning.

+ With regard to the criteria for identifying priority products for the food-processing industries, the products selected should in general, be suita )le for consumption by a large majority of the population and should be related to its needs and incomcs. Suitable policy measures should be taken to discourage use of scarce resources for the production of items that are non-essential or that meet thc requirements of only small or affluent sections of the population. However, the production of high-cost products even for domestic consumption should not altogether be ruled out, because in specific circumstances it might benefit the poorer section of the populatior~ indirectly through creation of employment and income opportunities.

In Nigeria as in most developing countries, the traditional skill and !ow levels of technology small-scale sector exist side by side with sophisticated technologies, and the development of the

12

of the small-

scale sector to produce low-cost products for mass consumption should be an important policy objective. In contrast to the organised large-scale inliustries, the small-scale units do not have the required expertise for the utilisation of by-product; and the conservation of energy. Therefore, it is the responsibility of the government to provide the necessary technical assistance to these units through national research and development, extension services and adequate financial assistance. The major problem of research and developn~ent consists in the upgrading of traditional and indigenous products. Modifications of such products anti processes would be particularly valuable if they were to lead to the adoption of locally acceptable vz riants of low-cost traditional products. Scientific research and development has a great part to play in such niodifications of products and processes. Upgrading and adaptation of the traditional technobgie; would be more relevant if it did not result in increase of cost or displacement of labour and if it increajed the marketability and demand for the end-products. The need for comprehensive institutional iir.angements for the development, application, transfer and adoption of technologies suited to local co~ditions is an imperative necessity. The strengthening of indigenous technological capabilities for technological self-reliance should be the ultimate goal. Appropriate institutional arrangements shmld also be made for the collection, analysis and dissemination of technological information ar.d for the introduction of training programmes. For the prevention of losses of processed ?ads, preservation of quality, protection of consumers' interests, and the facility to export processed products and appropriate packing methods also need to be identified and propagated. Promotion of thc use of indigenous raw materials for the packaging industry calk for intensive research and developmer t and suitable institutional support. Due care should be exercised in the choice of packaging techno ogies, so as not to add excessively to the cost of the end- product. In the tropics, traditional packaging techniques have been used for ages and are still in vogue for a variety of food products such as ::rains, fiuits, vegetables and fish. lmproved packaging technofogies are essential, particularly for export. In the connection, the possibility of establishing national {d regional packaging centres shou d be considered. Some developing countries have already established national packaging institutes to great advantage.

Conclusion A dependent economy that depends cn other nations to feed its citizens can never be truly

independent and viable. Nigerian mono-econonj. has been overly dependent on crude oil that is fast being exhausted with a projection into exploitation of ;olid minerals all of which are exhaustible. The only solid bedrock of an economy that will not only be buoyant but will also guarantee food security and self - sufficiency is agaiculare with vibrant agro-~rocessing nation-wide. In this regard f w d processing technologies as well as the development of sma.1- and medium- scale industries should be ernphasised as loss reduction measures and for abundance of cheap15 available preserved food and food products. This has been the premise of this paper. +& w t . 4 - b,+fd fic{,j # &* . h w d $<~d+.pd-~ld - a 4 ~ { & , &,, - References

- Borgstrom, G.(1968). Principles of Food Science Volume I , chapters 5 & 6. The Macrnillan Co., New York. Bressani, R.(1983). Effects of chemical change di~ring storage and processing on the nutritional quality of

common beans. Food and Nutrition Bulletin VoI. 5 w o . l),pp.23 - 34. Bruinsma, D.H, Witsenburg, W.W & Wurdemarm, W(1983). Selection of Technology for F o d Processing

in Developing Countries, Chapter 2 pp.4 - 19. A publication of the International Course in Food Science and N~trition (ICFSN), Pudoc, Wageningen.

Chou. M & Harmon, Jr., D.R.(I979). Critical Focd Issues of the Eighties. Chapter 10. pp. 149 - 150. Pergamon Press, New York.

Coursey, D,G.(1971). Biodeterioration of Materit Is ed. by Welters & Elphick, pp 464 - 471. Applied Science Publishers Ltd. Barkinj;, England.

National Academy of Sciences (1978). Postharve ;t Food Losses in Developing Countries, chapter 2, pp 15 - 25. National Academy of Sciencs, Washington D.C..