Organisation: Food and Agriculture Organization of the United Nations (FAO), Rome, Italy
Author: Carlos Gómez
Edited by AGST/FAO: Danilo Mejía, PhD, FAO (Technical), Emanuela Parrucci (HTML transfer)

CHAPTER XXXII - COWPEA: Post-Harvest Operations

Preface

1 Introduction

1.1 Economic and Social impact of cowpea

1.2 World Trade

1.3 Primary Products

1.4 Secondary Products

1.5 Requirements for export and quality assurance

1.6 Consumer Preference

1.7 Others

Preface

The present work provides information related to cowpea crops and mostly on cowpea post-harvest operation in developing countries. It is intended to be a reference for rural zones of West and Central Africa and East Asia where cowpea is widely grown. In South America, Brazil is the only country growing cowpea; in dry zones of Central America cowpea represents a high potential for cowpea culture.

Particularly in Nicaragua, with 73 percent of rural poverty and 53 percent of rural indigence cowpea crops (known as "alazín") are promoted by certain NGOs to improve soil and to prevent soil erosion. That is why cowpea crops could be an interesting alternative for grain and forage in dry zones of this country and Central America regions. (FAO/PESA NICARAGUA, 1999).

Cowpea is a legume that is extensively grown throughout sub-Saharan Africa. It is a subsistence crop, often intercropped with sorghum, maize and pearl millet. The grain provides valuable protein and the leaves are used as a nutritious vegetable. (IPM CRSP, 2000).

Millions of african farmers grow cowpea, some two hundred million africans consume cowpea, many, maybe a majority of these farmers are women. Cowpea grain, nutritious and inexpensive, serves as a source of cheap protein for both rural and urban consumers. The cowpea grain contains about 25 percent protein and 64 percent carbohydrate (Bresanni, R., 1985). Even the goats and the cattle benefit from cowpea, this genuinely african crop, for the hay left over after the grain is harvested as a high-value nutritious forage.(A BIOTECH, 2002).

Cowpea is an indigenous crop that has evolved from the native wild types and its genetic diversity is greater than that of any other crop in the dry african savannah. (IFAD, 2000). In semiarid zones of West and Central Africa, farmers traditionally cultivate two main types of cowpea: early maturing varieties grown for grain and late maturing varieties that are grown for fodder production. (Inaizumi, H. et al., 1999)

There are three recognized specific groups of cultivated cowpeas. Two of these are grown in Australia with most varieties grown for grain, forage and green manure. The other type, the yardlong bean, is a minor vegetable. (Imrie, B., 2000)

In industrialized countries as the United States and Australia, varieties of cowpea types are cooked, canned or frozen to make them ready to serve. (Quinn, J. 1999). Currently, cowpea forms part of "good-luck meal southern" traditionally prepared for New Year Day celebration. (Bean/Cowpea CRSP West Africa, Social Science Report April-Sept., 1998).

As with many other grain crops grown in the semi-arid tropics, the cowpea post-production system in developing countries is an important constraint. In particular, weevils - post-harvest pests - can destroy a granary full of cowpea in two or three months. (A BIOTECH, 2002)

1. Introduction

Cowpea is one of the most ancient crops known to man. Its origin and domestication occurred in Africa near Ethiopia and subsequently was developed mainly in the farms of the African Savannah. (Duke, cited by UC SAREP). Nowadays it is a legume widely adapted and grown throughout the world (Summerfield et al., cited by Aveling, T., 1999), however, Africa predominates in production as is shown in Fig. 1.

Fig. 1. Cowpea production throughout the world (dry grains).
Source: Compiled by the author from FAO (1990-2000) and other sources.

Cowpea is one of common names in English: cowpea, bachapin bean, black-eyed pea, southern, crowder pea, china pea and cowgram; in Afrikaans: akkerboon, swartbekboon, koertjie; in Zulu: isihlumaya; in Venda: munawa (plant), nawa (fruits) imbumba, indumba; in Shangaan: dinaba, munaoa, tinyawa. (Tindall, cited by Aveling, T. 1999). It is also known internationally as lubia, niebe coupe or frijol. However, they are all species Vigna unguiculata (L) Walp., which in older reference may be identified as Vigna sinensis (L) (Quinn, J., 1999)

It is an annual herb with a strong principal root and many spreading lateral roots in surface soil. The root system having larges nodules is more extensive than those of soybean. (McLeod, cited by UC SAREP).

Bradyrhizobiuim spp are the specific symbiotic nodular bacteria. Growth forms vary and may be erect, trailing, climbing or bushy, usually indeterminate under favourable conditions. Leaves are alternate and trifoliate usually dark green. The first pair of them is simple and opposite. Stems are striate, smooth or slightly hairy, sometimes tinged with purple. (Aveling, T., 1999).

Flowers are self-pollinating and may be white, dirty yellow, pink, pale blue or purple in colour. They are arranged in raceme or intermediate inflorescences in alternate pairs. Flowers open in the early day and close at approximately midday, after blooming they wilt and collapse. Pollinating insect activities are beneficial in increasing the number of pod set, the number of seeds per pod or both; however, there are no recommendations for the use of pollinating insects on cowpeas. (McGregor, S. E., 1976). Fig. 2 illustrates a graphic design of a cowpea plant.

Fig. 2. Graphic design of a cowpea plant

Fruits are pods that vary in size, shape, colour and texture. They may be erect, crescent-shaped or coiled. Usually yellow when ripe, but may also be brown or purple in colour.

There are usually 8-20 seeds per pod. Seeds vary considerably in size, shape and colour. They are relatively large, 2-12 mm long and weigh 5-30 g/100 seeds. Seed shape could be reniform or globular. The testa - the coat covering the grain - may be smooth or wrinkled; white, green, red, brown, black, speckled, blotched, eyed (the hilum - central line - is white surrounded by a dark ring) or mottled in colour. (Aveling, T., 1999). Fig. 3 shows a handful of cowpea grains.

Fig. 3. Cowpea grains

Its geographical range is wide, from Warm Temperature Thorn to Moist through Tropical Thorn to Wet Forest Life Zones. Cowpea cannot be grown for grain as far north as soybean because it is more sensitive to frost. (Duke, cited by UC SAREP). It grows best in hot areas and can produce a yield of one ton seed and five tons hay per hectare with as little as 300 mm of rainfall. Long taproot and mechanisms such as turning the leaves upwards to prevent them to become too hot and closing the stomata, give to cowpea an excellent drought tolerance. (Van Rij, N., 1999)

Cowpea is considered more tolerant to drought than soybean or mung bean because of its tendency to form a deep taproot. It has a competitive niche in sandy soils, does not tolerate excessively wet conditions, and should not be grown on poorly drained soils.

One of the most remarkable things about cowpea is that it thrives in dry environments; available cultivars produce a crop with as little as 300 mm of rainfall. This makes it the crop of choice for the Sahelian zone and the dry savannahs, though cultivars that flourish in the moist savannahs are available as well. (Bean/Cowpea CRSP West Africa Mission).

Varieties of cowpea are said to be tolerant of Aluminium and to be adapted of poor soil if Ph is between 5.5 and 6.5. On the whole, it is less tolerant of alkaline and salinity condition, but intolerant of excess amount of Boron. (Duke cited by UC SAREP). Cowpea crop often responds favourably to added Phosphorus, although there was non-significant increase in cowpea grain yield up to Nitrogen application rate of 30 kg/ha (Agbenin et al, cited by UC SAREP).

Length of growing season varies with type: 100 days in determinate type, 110 days in semi- determinate, 120 days in ranking type. The climate will also have an effect on the length of the growing season: the hotter the weather, the shorter the maturity period. (Van Rij, N., 1999) Fig. 4 shows a determinate type cowpea cultivated under irrigation.

Fig. 4. A fine stand of an irrigated cowpea crop

1.1 Economic and Social impact

Cowpea is the most economically important indigenous african legume crop. (Langyntuo, A.S., et al., 2003). Cowpeas are of vital importance to the livelihood of several millions of people in West and Central Africa. Rural families that make up the larger part of the population of these regions derive from its production, food, animal feed, alongside cash income. (**)

Food habits in West and Central Africa are mainly based on tuber crops (cassava, yam) and cereal (maize, rice, millet). Although they have a high nutritional value, grain legumes are a minor component of food diet. That is the reason why tentative efforts have been made to introduce soybean in african food habits and farmer activities, but with little success because of its undesirable taste and cooking difficulty. Unlike soybean, cowpea is appreciated and different traditional African meals and seasonings are prepared from cowpea, among them homemade weaning foods. (Lambeth, C., 2002)

Fig. 5a. Farmers stack dry cowpea fodder in traditional structures for storage

Cowpea is a most versatile African crop: it feeds people, their livestock and the next crop. In the Americas, also known as "black-eyed peas", cowpea is a high protein food, and very popular in West Africa. The plant itself can be dried and stored until needed as fodder for livestock. As a nitrogen-fixing legume, cowpea improves soil fertility, and consequently helps to increase the yields of cereal crops when grown in rotation.

Fig. 5b. Farmers stack dry cowpea fodder in trees out of reach of wild antelopes

Cowpea is referred to as the "hungry-season crop" given that it is the first crop to be harvested before the cereal crops are ready. It is a crop that offers farmers great flexibility. They can choose to apply more inputs and pick more beans, or - if cash and inputs are scarce - they can pick fewer beans and allow the plant to produce more foliage. This means more fodder for livestock, so that lower bean yields are balanced by more livestock feed, which in turn translates into more meat and milk. This flexibility in use that makes cowpea an excellent crop under the challenging climatic conditions faced by African farmers. (Okike, I., 2000). Figs. 5a and 5b show two different ways to stack cowpea forage in difficult conditions of sub-Sahara region.

According to Blade et al cited by Aveling, T., 1999, ninety-eight percent of cowpea grown in Africa has been intercropped for a long time with other crops. It can be also intercropped with large taller plant such as maize particularly in rainfall areas because of the exceptional shade tolerance. (Johnson cited by Aveling, T., 1999).

Traditionally in West and Central Africa, cowpea is grown on small farms, often intercropped with cereals such as millet and sorghum. The cowpea and cereal are usually planted in alternating rows, although recent research at IITA has shown that planting four rows of cowpea to two rows of cereal is more productive. The cereal is planted first, followed by the cowpea.

The fast growth and spreading habit of traditional cowpea varieties suppress weeds, and soil nitrogen is increased which improves cereal growth. The two crops are harvested at different times, distributing available labour force.

Fig. 6. Intercropping of sorghum with traditionally cowpea

Figs. 6 and 7 show the differences between traditional and improved cowpea varieties intercropped with sorghum.

Fig. 7. Intercropping of sorghum an IITA-improved cowpea variety.

Cowpea also contributes to the sustainability of cropping systems and soil fertility improvement on marginal lands through nitrogen fixation, provision of ground cover and plant residues, which minimize erosion and subsequent land deterioration. (**). The deep root systems of cowpea help to stabilize soil, and the ground cover it provides preserves moisture; these traits are particularly important in the drier regions where moisture is always needed, soil is fragile and subject to erosion. (Bean/Cowpea CRSP West Africa Mission).

In Coachella Valley, California, in addition to decreasing total weed population, summer cowpea mulch improved the soil temperature regime by acting as buffer temperature. (Ngonagjio, M. et al., 2000)

In Nigeria the major constraints to the adoption of dry season dual-purpose cowpea include insect attack both in the field and in storage, insufficient water, nematodes, lack of land, and lack of seed. The magnitude of these problems also varies with location. (Inaizumi, H., et al, 1999). Fig. 8 shows a dual-purpose cowpea variety.

Fig. 8. IITA improved dual-purpose cowpea: grain and fodder

Cowpea is a crop well suited to Niger's climate and soils and well adapted to Niger's generally extensive agriculture. Strangely, cowpea is hardly consumed at all by Niger's population.

The protein in cowpea seed is rich in amino acids, lysine and tryptophan in comparison with cereal grain; however, it is deficient in methionine and cystine in comparison with animal protein. Table 1 shows chemical composition of different parts of cowpea plant. (Davis, W. et< al.,1991)

Table 1. Chemical composition of cowpea (%)

The comparative cost of protein in selected food items in Nigeria is shown in Table 2. This data reveals that soybean is the cheapest protein source compared with other protein-rich foods such as beef. Compared with other sources of plant protein, cowpea is - after soybean - more nutritious and the crop has a wider ecological adaptation. (Osho, S.M and Dashiell, K., 1997)

Table 2. Comparative cost of protein in selected food sources in Nigeria

Production costs for cowpea vary depending on the technology used in particular varieties, fertilizer, tillage and pest management. Bean/Cowpea CRSP studies and other sources have established that labour often accounts for over 70 percent of the total cost of production. (Langyintuo, A.S., et al., 2003). In Africa, cowpea production appears generally profitable, but return varies widely from place to place as it is shown in Table 3.

Table 3. Cowpea sample budgets in selected countries of West and Central Africa in 1999 (US$ ha-¹) ¹

1.2 World Trade

The Americas

Of the developed countries, only the United States is a substantial producer and exporter. (Imrie, B., 2000). However, cowpea areas and production figures for the United States as a whole are not well known but considering the production during 1990s, it can be classified into three categories:

• about 21 000 hectares of cowpea were grown annually for commercial dry grain mainly in California and Texas with approximately 41 000 tonnes;

•  about 11 000 hectares of cowpea were grown for frozen and canned southern peas, mainly in the south eastern part of the United States;

•  about 30 000 hectares of cowpea were grown in home gardens mainly for fresh southern peas. (Hall and Frate, cited by Langyintou, A.S., et al., 2003)

The United States exports around 2 000 tons per year of very high quality cowpea. "In a shop anywhere in the world, if there is very large cowpea (> 25 grams per 100 grains) with white testa and very black eyes, it is probably a California product". (J. Lowenberg-DeBoer, personal communication, 2003)

The largest commercial application is for types most frequently marketed as black-eyed peas, which are harvested and then sold after cleaning and drying. In the south of the Unite States there is a substantial production of a variety of cowpea types, that after drying are sold to processors which in turn cook and soak the dried product, to make it ready to heat and serve.

These products may be either canned or frozen and are referred to as "southern peas". Price for dried black-eyed purple hull peas fluctuates due to normal production and demand factors, but range from $0.55-0.66 per kilogram for the canned market and $0.55-0.88 per kilogram for the dry seed market (Quinn, J. 1999)

With crops such as dried black-eye or purple-eye peas, it is generally preferable to have a contract for growing the crop before planting. However, this market is fairly well established throughout the south and in California, so it may be possible to sell the crop successfully without having a production contract. Growers are advised to identify their markets as early as possible, rather than waiting until after harvest. It may be possible to direct market dried black-eye, or purple-eye peas to a food broker or retailer in Indiana. (Quinn, J. 1999)

In the United States dry cowpea productions are likely to occur costs similar to the costs of dry edible bean production. Fresh green cowpea requires a specialized pea harvester, therefore, growers may need a contractual relationship with a processor/harvester for those services. Small areas of cowpea may be hand harvested and may find a niche in a specialty/gourmet market. Hand harvesting for a fresh green cowpea market will require considerably greater labour and management inputs.

Prospective growers need to investigate potential markets prior to planting. The distance to market, availability of labour and short-term storage along with vagaries of the market and of the grower's individual situation should be considered. (Davis, W. et al., 1991).

Brazil is the second largest producer of cowpea in the world, but most of that product seems to be consumed within Brazil. Little cowpea is exported from Brazil. Cowpea is also produced in small quantities in several Latin American countries, but import/export data are not available. (J. Lowenberg-DeBoer, personal communication, 2003)

East Asia

In the 1990s Myanmar exported annually around 30 000 tons to India and Middle Eastern Countries and India imported annually some 15 000 to 20 000 tons of cowpea mainly from Myanmar. (J. Lowenberg-DeBoer, personal communication, 2003)

Africa

Since the FAO stopped publishing cowpea statistics in mid of 1980 s, there is no reliable source of international statistics on cowpea production or marketing. Many cowpea scientists need such statistics. Biological scientists need them to explain and justify their programs. Statistics are the basic elements for socio-economic research. (Bean/Cowpea CRSP West Africa, Social Science Report April-Sept., 1998)

In Africa, information on cowpea marketing and trade is lacking and data on cowpea production economics scattered, because marketing research has focused on export crops such as cocoa, coffee, cotton, groundnut and to a lesser extent cereals. (Van der Laan cited by Langyintou, A.S., et al., 2003)

The two main sources of data are: FAO (FAO, 2000) complemented by the statistical service department of various countries, and information collected by the socioeconomics groups of the Bean/Cowpea CRSP. Production date provided by individual governments can be inconsistent because:

•  many consider cowpea as a minor crop and cowpea data are aggregated with that of common bean;

•  in some african countries, a hectare of millet-cowpea intercropped with millet is usually counted as one hectare of each crop in the national statistics;

•  in other african countries, cowpea area statistics are adjusted to a "monocrop equivalent";

•  data from Nigeria, Niger, Mali, Senegal, Mauritania and Burkina Faso are regularly submitted to the FAO but those from Ghana, Benin, Togo, Côte d'Ivoire and Cameroon are not. (Langyintou, A.S., et al., 2003)

However, FAO estimates that 3.3 million tonnes of cowpea dry grain were produced worldwide in 2000. (IITA Research, 2001), but only a small proportion enters international trade.

More than 8 million hectares of cowpea are grown in West and Central Africa. Also it is known that Nigeria is the largest producer with 4 million hectares. Other producers are Niger, Mali, Burkina Faso and Senegal. (**).

The largest production is in Africa with Nigeria and Niger predominating, but Brazil, West India, Myanmar, Sri Lanka, Australia, the United States, Bosnia and Herzegovina all have significant production. (Quinn, J., 1999)

About 87 percent of that area is in Africa, 10 percent in the Americas and the rest in Europe and Asia. Nigeria is the largest producer accounting with 45 percent of the total, followed by Brazil that produces 17 percent on 1,15 million hectares annually. (Pereira et al cited by Langyintou, A.S., et al., 2003). Around 3.7 millions tonnes of cowpea are produced annually on about 8.7 million hectares, throughout the world (Table 4 ).

Table 4. Supply and demand for cowpeas in selected countries of West and Central Africa (1990-1999)¹

A dense population and oil revenue in West Africa create an enormous effective demand of cowpea. Structured cowpea market in West Africa is part of an ancient trade that links the humid coastal zones with the semiarid interior. In the humid coastal areas, it is relatively easy to produce carbohydrate (e.g. cassava, maize, rice), but because of pests and diseases it is difficult to produce animal or vegetable protein.

On the contrary, lack of rainfall limits grain production in the interior, but it creates good condition for livestock, cowpeas and groundnuts. In the sub-Sahelian zone, there is a well-developed network of village buyers who assemble small quantities from individual farmers into 100 kg bags and merchants who transport and store the bags. (Lowemberg-DeBoer, J. et al., 2000)

As a result, in West Africa protein products traditionally move south to the humid area, while carbohydrates move north. Cowpea is actively traded from West to Central Africa because of the comparative advantages that drier areas of West Africa have in protein production. (Langyintuo, A.S, et al., 2003). Fig. 9 illustrates distribution of cowpea production and movement in West and Central Africa.

Fig. 9. Distribution of cowpea production in West and Central Africa.

At least, 285 000 tons of cowpea are shipped among countries in the region each year. This is probably an underestimate because the official sources on which the estimate is based do not collect data on all flows. In 1998 Burkina Faso imported about 8 000 tons from Niger and exported a total of 5 500 tons to Togo, Côte d'Ivoire, Ghana and Benin.

Table 5. Estimated cowpea imports and exports among selected West African Countries, 1998/1999. (metric tonnes)¹

It is estimated that Nigeria's average annual imports of 260 000 tons per year from Niger accounts for about 73 percent of Niger's surplus production. Cowpea trade between Nigeria and Benin is bilateral. Togo and Ghana, and Ghana and Benin trade bilaterally as well. Gabon depends on Cameroon, Togo, Benin and Nigeria for cowpea. Mauritania, Gambia and Guinea Bissau rely on Senegal. (Table 5).

Cowpea trade in West and Central Africa is clustered around Senegal and Nigeria. Senegal exports to its neighbours to the north and south. In contrast, Nigeria imports from its neighbours more than it exports.

Market structure in West and Central Africa

Grain marketing is organized in formal and informal places. Formal market places are designated locations managed by public organizations. Informal markets are not officially recognized and therefore, not subject to most government controls. An informal market may be a group of women who assemble every week in the centre of a village or who buy from farmers on roadsides. Farmers usually accept lower prices because they are not aware of the market prices or because they lack the time, money or means to transport cowpea grains to the market.

Cowpea passes from farmers to consumer through various market channels. Farmers usually sell their surpluses to rural assemblers, who in turn sell to urban wholesalers directly or through commission agents.

Large wholesalers hold large stocks for sale to retailers when prices are high enough to pay for cost of procurement, storage, handling and a margin for profit. They may also be involved in the import and export of maize, groundnut and other grains. Small wholesalers handle smaller volumes and use markets in their homes neighbourhood and acquire the grains from wholesalers and commission agents for sale to consumers in smaller quantities.

In Nigeria, Ghana, Burkina Faso, Togo and Benin grain traders constitute themselves into commodity-based associations to promote better marketing conditions and discuss general guidelines for grain prices. Traders discuss grain pricing during association meetings but prices are fixed by individual traders. Factors influencing price setting are: grain quality, selling time, transport, storage, market tolls, taxes and taxes.

Prices

At harvest, traders tend to heap their measures; it is common to observe 5-10 percent more grains (on a standard bowl of 2.5 kg or on a 100 kg bag) than the average depending on the relationship between seller and buyer. This is often the reverse during those months of the year when prices are high. In Niger, Benin, Nigeria and Ghana, prices tend to rise above the average in February through September when grains are scarce.

The general price trend in Fig. 10 explains that price series tend to move together. However, the series from Niger, a major surplus producer is consistently lower than those of Benin, Nigeria and Ghana. Prices in Gabon are about 100 percent higher than those in Cameroon, which is the main source for the Gabonese market.

Fig. 10. Cowpea prices in selected West African countries

Marketing margins for cowpea

Cowpea trade is only possible if traders earn enough to cover their costs. In Ghana, about 70 percent of consumer expenditure for domestically produced cowpea goes to pay the cost of production and farmers' returns. Six and 4 percent contribute to transport cost and marketing cost respectively, while traders receive 20 percent as remuneration for their services (Table 6). (Langyintuo, A.S. et al., 2003)

Table 6. Marketing margins for cowpea in selected countries in West and Central Africa (US$ t^-1)

Nigeria

The production trend of cowpea in Nigeria shows a significant improvement with about 440 percent increase in area planted and 410 percent increase in yield from 1961 to 1995 (Ortiz, R. 1998). The development within the two decades is attributable to the significant advances made on cowpea seed improvement in the drylands by the IITA. (**).

Although Nigeria is the largest producer of cowpea in the world producing about 56 percent of the world production, it is also the largest consumer of cowpea in the world. (NAQA, 2001). That is the reason why substantial amounts of cowpea come to Nigeria from neighbouring countries especially Cameroon and Chad. A large proportion of cowpea from Burkina Faso and Mali are sold into Côte d'Ivoire. (Lowemberg-DeBoer, J. et al., 2000)

In Nigeria the organization of traders in Kano's Dawanau market - the largest cowpea market in the world - differs from other trading organizations. Traders are organized into a formal market union, "Dawanau Market Development Association" comprised of smaller associations such as Dawanau Farm Produce Merchant Association, Restaurant Owners Association, Transport Operator Associations, etc. The main role of the major association is to negotiate with the government over issues such as taxes and market infrastructure. (Langyintuo, A.S. et al., 2003)

Niger

Development of cowpea production, which concerns 5 regions of Niger (Zinder, Maradi, Tahoua, Tilaberi and Dosso) is principally justified because of its good export market value. Cowpea is exported unfinished. The crop is however difficult to store, and requires insecticides to protect against weevils when stored more than 6 months. State intervention in the cowpea industry mainly concerns the marketing and sale of output, which at present is operated by specialty traders (about 30 principal players), and by many active, informal distribution and sales channels

Production data indicates that cowpea is the third-largest food crop produced by Niger, after millet and sorghum. Cowpea is a crop well suited to Niger's climate and soils and well adapted to Niger's generally extensive agriculture. Strangely, cowpea is hardly consumed at all by Niger's population (less than 15 percent of production is consumed by the country). Cowpea export is mainly to the following countries:

• Nigeria (strong demand, continued growth);

• Ghana;

• Benin and Togo (lower export levels and market growth).

Prices and production vary widely from one year to the next. (European Union, 2002) 

Niger trade's potential and constraints

Development potential for the Niger cowpea industry is essentially dependent on agricultural and ecological factors and on market evolution in the West African region. In particular, the following potential can be noted:

• cowpea crop is well entrenched as a traditional production of Niger's peasant farmers. Varieties cultivated are best adapted to the climate and soils under extensive cultivation and are able to resist drought and vermin. Cowpea production has become a cash crop, as well as a subsistence crop, notably for animal fodder;

• utilization of helm as a source of fodder also explains why cultivation of cowpea is expanding, because cowpea helm is protein-rich and economizes the draw on forage during the dry season;

• Niger's production of cowpea, as an export commodity to regional countries, enjoys strong and sustained demand. Prices in these markets, outside the harvest season are attractive;

• export industry organization for cowpea production is strongly dominated by exporter trading entities, which control most channels for the centralization of supplies and their subsequent sale. The keys for the continued market power of export traders is their control of warehousing and storage facilities and treatment of cowpea stocks, enabling them to gain the best prices on sales in consumer markets, in off season periods.

Constraints impeding on more rapid development of Niger's trade and industry are mainly of financing:

• concerning production, low or no access to credit and loans in rural areas very often forces peasant farmers to sell their production immediately after harvest, that is when prices are at their lowest levels;

• concerning commercial trading, little access to credit and loans, or at least loans at reasonable interest rates, prevents traders from intervening in the market in the sense of stabilizing seasonal fluctuations in final markets and their prices.

Ghana

Ghana is major producer of cowpeas but in addition it imports about 10 000 t annually. About 30 percent of the Ghanaian imports come from Burkina Faso and the rest form Niger. In Accra, the large, rough coated Nigerian cowpeas are sold for a premium, but they need to be marketed quickly because they do not store well in the humid coastal climate. (Faye, M. et al., 1990)

Senegal

In northern Senegal as climate grew drier and the ground parastatal declined, cowpeas have increasingly replaced groundnut as the legume of choice. Some cowpeas are exported to Mauritania and Gambia, but the transportation cost and lack of market links limit access of Senegalese cowpeas to the large market in Ghana, Nigeria and elsewhere along the african coast.

Senegal is the only country in the region with a substantial cowpea processing industry. It has identified five companies producing cowpea-based weaning food, cowpea flour and cowpea-based crackers. All products are made from recipes developed by ISRA's Food Technology Institute (IITA). In addition, there is a cracker manufacturer in Nouachott, Mauritania, that uses primarily cowpeas from Senegal. (Faye, M. et al., 1990)

Cameroon

A preliminary study of the structure of the cowpea market in northern Cameroon was completed. The general objective of this study was to characterize the marketing of cowpea produced in Northern Cameroon, including analysis of marketing costs. Sixty participants were interviewed in the markets where cowpea price and quality data were collected ( Maroua, Salak, Mokolo and Banki), including farmers, local retailers, wholesalers and rural intermediaries. Main results were:

• Nigerian merchants are a major buying presence only in the border market of Banki. In the other markets Nigerian merchants are seen only when cowpea shortages drive prices in Nigeria very high;

• cowpea storage capacity in Maroua is about 25 000 to 30 000 tons. Annual production of cowpea in the far north province of Cameroon in the last decade varied from 15 000 to 45 000 tons. Thus, if the Cameroon government cowpea production figures are accurate, a high proportion of cowpea production in the far north province can be stored by Maroua merchants.

• some 15 000 to 20 000 tons are shipped from Maroua each year to markets in southern Cameroon, principally Douala and Bafoussam. In southern Cameroon markets some cowpea are resold to merchants from Gabon and Congo.

• marketing costs to southern Cameroon include: Trucking from Maroua to Douala or Bafoussam, 40 000 to 50 000 FCFA/ton or 3000 to 4 000 FCFA/sack; storage in Douala or Bafoussam until sale, about 300 FCFA/sack, about 30 FCFA/sack for taxes and other fees and 50 FCFA/sack for each time a sack is loaded or unloaded. Typically, the seller or his representative will accompany a load of cowpea to the south. This adds about 400-500 FCFA/sack. Total marketing cost is estimated at 3 830- 4 930 FCFA/sack.

• typical price differences for the same period between Maroua and southern Cameroon suggest that the cowpea trade can be modestly profitable. Price difference between harvest and latter periods indicate returns to capital invested of about 50 percent. (Bean/Cowpea CRSP West Africa Mission). Table 7 shows the variability of cowpea prices depending on periods and locations in Cameroon.

Table 7. Cowpea price ranges at selected markets within Cameroon by period

Australia

Cowpea are grown as a green manure crop in coastal sugarcane areas, as a forage or dual-purpose grain/forage crop in coastal land sub coastal southern Queensland, and a grain crop from central Queensland to central NSW.

The predominant grain type traded is the "black-eyed pea", - a large white seed with a black patch around the hilum - although markets exist for seed with a range of sizes and colours. Small red-seeds cowpeas are sometimes substituted for adzuki beans in Japan (Imrie, B., 2000). Table 8 shows production of cowpea dry grain in Australia.

Table 8. Production of cowpea dry grain in Australia (1987 to 1992)

Sri Lanka

Cowpea is an important legume crop in Sri Lanka. Cultivated areas and production are shown in Table 9. (***)

Table 9. Area and Production in Sri Lanka (1997 to 2001)

1.3 Primary product

In Southern Africa, cowpea is at present planted primarily for fodder, although it is also used for grain production, green manure, weed control in forestry plantations and as a cover or anti-erosion crop. Summerfield et al cited by Aveling, T., 1999 reported that in Nigeria the cowpea seeds are sometimes used as a coffee substitute and the peduncles of certain cultivars are used for fibre production.

In some areas of Africa, cowpeas are cooked as green pods and the swollen beans are consumed. These fresh cowpea pods, together with fresh green leaves, are the earliest foods available at the end of the "hungry time". Fig. 11 shows an example of succulent leaves that can be harvested as soon as 21 days after planting and cultivars that produces harvestable grain after only 60 days after planting. (Bean/Cowpea CRSP West Africa Mission)

Fig. 11. Green pod and succulent leaves of cowpea

Cowpea can be used at all stages of growth as vegetal crop. The tender green leaves are an important food source in Africa and are prepared as potherb, like spinach. Immature snapped pods are used in the same way as snapbeans often mixed with other food. Green cowpea seeds are boiled as a fresh vegetable. Dry mature seeds are also suitable for boiling and canning.

In June 1996, a survey conducted by ISRA/CRSP reported that improved cowpea varieties, including CB5, are grown mainly for the green pods, which are available two or more weeks before those of the traditional varieties. Green pods are an important source of food for farm families during the period before cereal crops are mature.

In many areas of the world, the cowpea is the only available high quality legume hay for livestock feed. Digestibility and yield of certain cultivars have been shown to be comparable to alfalfa. (Davis, W. et al., 1991). In Niger, the haulm (or halm) of the plant is consumed as dietary habits and traditions, and cowpea plants are widely used for animal fodder.

They are also a source of cash income when they can be marketed along the roadside to passing travellers. Women handle most of the cowpea green pod marketing. However, green pod area is limited because it is labour intensive and green pods must be consumed fresh (there is no canning industry, as in the southern United States). To achieve greater impact, improved varieties would need to be used for dry cowpea production. (Bean/Cowpea CRSP West Africa, Fy 97 Annual report October 1995-April, 1997)

In the United States the major market of cowpea as a dried seed is black-eyed pea and pink eyed/purple hull. They are often cooked with water and canned or frozen to make them ready to heat and serve. (Fig. 12)

Fig. 12. Some seed of available cowpea varieties in the United States

However, some cowpeas are harvested while the seed are high moisture and sold fresh. Both cases are referred to as "southern peas". (Quinn, J. 1999).

1.4 Secondary and derived product

In Africa, particularly in Ghana, the growth in the dietary share of cowpea has been constrained by high preparation time and labor requirement, undesirable product characteristics including beanie flavour, low digestibility and abdominal upset as well as post-harvest grain losses caused by insect pests.

Cowpea is prepared for consumption in grain, split and ground forms. The ground form has traditionally been a favourite of rural households in Northern Ghana because cowpea flour is less susceptible to post-harvest pest damage and can be used in many different dishes thus enhancing food security between harvests. (Bacho cited by Nyankori, J., 2000).

Food and nutrition technologies developed in the last thirty years promise to increase the cowpea share of Ghanaian food consumption through improved grain milling, more efficient nutrient extraction and new cowpea based-food products. Table 10 establishes a comparison between traditional and mechanized processing of cowpea flour.

Table 10. Comparison of traditional and mechanized processing of cowpea flour

The cowpea products is a nascent industry, apparently in stage two of the product life cycle; the introduction stage is characterized by a limited number of competing firms, low profitability, and high prices. (Nyankori, J., 2000)

Cowpea flour is sold whole or mixed, mainly in bulk or packaged in unbranded packets similar to Fig. 13.

Fig. 13. Packed unlabeled flour product.

Alternatively, there are other competitive flours included branded products like Tom Brown, Selasie and Gary (Fig. 14.)

Fig. 14. Branded composite flour product.

1.5 Requirements for export and quality assurance

Skin and eye colour and texture grain

Varieties of cowpeas differ in testa characteristics, grain size as well as in skin and eye colour. Although, the number of varieties exported by any country is usually limited to 1 to 2 up to nine may be on sale in domestic markets of West and Central Africa. Table 11 demonstrates that the predominant grain colour in african market is white.

Table 11. Cowpea characteristics in selected markets in West and Central Africa (%)

On the other hand, the importance of testa texture varies by country. In Ghana, the cowpea grains are mostly smooth textured. On the contrary, cowpea sold in Mali, Senegal and northern Cameroon are rough texture.

Cowpea rough skin is linked to the type of food prepared and to storage conditions. Rough skin is easy to dehull and therefore easier to use for those dishes that traditionally require removal of the testa, for example "moin-moin". Smooth skinned cowpeas tend to be more common in humid areas where storage conditions are poor. (Langyintuo, A.S. et al., 2003)

A pilot study of cowpea price and quality relationships carried out for CRPS in Maroua, Cameroon during September 1996 is an example of socio-research with regional implications. Results through April 1997 indicate that consumers in Maroua are very aware of seed size differences and that they are more sensitive to cowpea insect damage than previously thought. The Maroua data indicates that a statistically significant price discount may start to be observed when one third of the grains have holes (Bean/Cowpea CRSP West Africa, Fy 97 Annual report October 1995-April, 1997)

Grain size

Analysis reported at the PEDUNE/RENACO/IITA/CRSP Cowpea Review and Planning Meeting, Ibadan Nigeria on March, 1998 indicates that cowpea characteristics vary widely and that grain size is the most important single factor influencing price. (Table 12)

Table 12. Average, minimum and maximum for cowpea characteristics in four markets, northern Cameroon and three markets in northern Ghana

Product quality

Storage plays a significant role in product quality and thus grain prices. However, quality-price relationship are less significant during the dry season when poor quality products may be sold at a higher price than good quality grain at harvest time. (Langyintuo, A.S. et al., 2003)

According with Cameroon data, bruchid holes have a negative impact on price, but so far this has not been shown to be statistically significant. The level of bruchid damage in the Cameroon samples has been relatively low. The average is only 13 holes per 100 grains and very few samples go over 30 holes per 100 grains. The hypotheses about why this low level of damage is observed focuses on:

a) increasing use of modern storage techniques, both insecticides and CRSP non-chemical methods;

b) merchants sort out damaged grain to keep the level of damage below some consumer threshold, and

c) the ample supply of cowpea in 1997 and 1998 which allowed low quality grain to be diverted to animal feeding. (Bean/Cowpea CRSP West Africa, Social Science Report April-Sept., 1998).

In Australia, most crops are traded by members of the National Agricultural Commodities Marketing Association, which has established standards for grain quality. Economic return is dependent on seed quality, being around US$ 800/t for grade but dropping to US$ 250/t or less for stockfeed. This dichotomy in pricing makes cowpeas more risky for growers than mung bean, the summer pulse alternative. (Imrie, B. 2000)

1.6 Consumer Preferences

United States

Akara is an ethnic food that is very popular in West Africa. It is made from cowpea paste that is whipped into a batter, seasoned with fresh peppers (green or red, hot or mild), onions and salt, and deep fat fried. This product is relatively unknown in the United States but provides a novel form for the use of cowpeas.

A study to assess the acceptability of Akara by americans who are regular consumers of fried foods was carried out. Varieties used were Blackeye, California Cream (white-eye), and a 2:1 mixture of California Cream: Kunde Giraffe (wild, short-season black-eyed type that is insect and drought resistant). The seed coats were not removed as is done in the traditional West African process. Batter moisture content was adjusted to 64 percent to obtain optimum paste handling properties.

Sensory attributes were not significantly affected by variety. Hedonic ratings (1 = dislike extremely, 9 = like extremely) ranged from 7.2 to 7.6 for appearance, from 7.2 to 7.7 for colour, from 6.6 to 7.1 for texture, from 6.7 to 7.1 for aroma, from 6.4 to 6.8 for flavour, and from 6.5 to 6.9 for overall acceptability. These highly acceptable ratings indicate positive market potential for this product. (Patterson, S. P. et al., 2000).

In the United States, later use included incorporating cowpeas into the traditional "good luck meal southern" traditionally prepared for New Year's Day. Among farmers who save seed, the seed is first dried and then frozen (Bean/Cowpea CRSP West Africa, Social Science Report April-Sept., 1998)

The Bean-Cowpea Collaborative Research Support Program funds UGA's akara project. The goal of this project is to broaden the way americans view and eat beans and cowpeas. UGA food scientists are working to introduce "Akara", to United States consumers through the frozen food and fast-food markets. Similar to cornmeal hush puppies, "Akara" is made from deep-fried cowpea (black-eyed pea) paste.

Fig. 15. An "Akara" low-fat fried food

Credit: Sharon Omahen

Most Southerners are accustomed to eating black-eyed peas typically used as a fresh or frozen vegetable for boiling. So eating black-eyed peas in the form of a fried food would be a new experience.

Akara's major drawback has been its high fat content, therefore UGA's newest formulations have solved that problem because the content fat has been significantly reduced. (Fig. 15)

A consumer tests conducted by UGA food scientists have found that Americans like "Akara" because of its ethnic appeal. These surveys also show Americans would best accept "Akara" as a fast food or as a fully cooked, frozen, reheatable item. (Omahen, Sh., 2002)

West and Central Africa.

Consumers in the West and Central African countries generally prefer large grains and discount prices of grains that are damaged by insect pests. Their preferences for grain and eye colour vary form place to place.

Ghanaian consumers pay a premium for black-eye cowpeas whereas those in Cameroon discount black-eye ones. The most common preference for testa colour is white, but in some areas consumers prefer red, brown or mottled grains. (Langyintou, A.S., et al., 2003)

Nigeria

Cowpeas are frequently consumed in West Africa as fried "Akara balls and steamed moin-moin", both of which are prepared from ground beans. In order to estimate this aspect of consumer acceptance, these dishes were made from local recipes, using flour of IITA cowpea cultivars. This work was done in cooperation with the test kitchen of the University of Ibadan.

Taste panels graded the product on the basis of taste, texture, and appearance. A high-quality cultivar was always included in the test as a standard, so that results were stated as preference or non-preference of the IITA cultivars compared with the standard.

In order to estimate the acceptance of new IITA cowpea cultivars by consumers in West Africa, several factors that determine acceptance were measured. These included cooking time and water uptake for whole beans, as well as taste, texture, and appearance of dishes prepared from ground beans. Cooking time and water uptake (or the ability to "fill the cooking pot") were measured by plotting increase of wet seed weight as a function of the time that beans were submerged in boiling water.

More than 100 cowpea lines were screened for these two factors. Cooking times ranged from 35 to 90 minutes and water uptake from 98 to 170 percent. Only those lines with short cooking time and high swelling capacity were acceptable to consumers. (Luse, R.A. 1980)

It also was determined that grain legumes are an important source of protein in the diets of people living in villages in Southern Nigeria, but that green leafy vegetables and other components of the soups and stews eaten daily also contribute more protein than is usually realized.

Other aspect to be considered is the daily food intake. A good proportion of daily food intake of Nigeria consists of food purchased from vendors in commercial eating-places. The principal food sources are:

• indigenous african food crops such as yam (Dioscorea, sp.), Cowpea (Vigna unguiculata), and locally reared animal;

• non-indigenous introduced crops such as cassava (Mandioca sp. And rice (Oriza sativa) and

• imported crop and animal products such as wheat (Triticum vulgare) and fish e.g. mackerel (Scomberomorus tritor)

Lately, there is a concern about the erosion of african genetic resources because of change in taste and urbanization, which has favoured the importation of food and the neglect of indigenous food crops.

Cowpea (probably the most important source of non-animal protein in the tropics) is under-utilised in commercial eating-houses in Nigeria. This could be due to the required long preparation and cooking time. Even in places where cowpea is found, it is served to accompany boiled or fried plantain. Other food preparation from cowpea such as "Akara" are not served routinely in the hotels but it can be prepared for customers on request. (Abiose, S., 1999)

On the other hand, consumption of cowpea flour has increased in Nigeria. A survey has shown that consumption of cowpea increased more than double in areas where villages mills were installed, despite of a price increase of 500 percent. (CANR, 2001)

Ghana

An exploratory market study of cowpea products in Ghana using data from case studies shows that cowpea flour, the main value added product, is typically sold in bulk or unbranded small packages through retail and wholesale outlets and directly to consumers including individuals, institutions and the catering industry.

Cowpea flour is less prone to insect pest attack and consequently is a major source of food during the dry season ant the period between harvests. However, the growth in the dietary share of cowpeas has been constrained by high preparation time and labour requirements, undesirable product characteristics including beanie flavour, low digestibility and abdominal upset as well as post-harvest grain losses to insect pests.

There are several dishes using cowpea flour produce in the household and these provide a varied nutritious diet and have added desirable attributes, which include easy cooking, availability and favourable taste. Although, a high proportion of processors are aware of the new cowpea utilization technologies, only a low percentage has capacity expansion for the next years.

The full impact of new utilization technologies will be realized over several years following substantial private capital investment in processing, marketing and strategic promotional activities. New formulations for utilization of cowpea flour are shown in Table 13.

Table 13. Some new formulations for utilization of cowpea flour in Ghana

The market study in Ghana also established Consumer Preference for selected product attributes measured in terms of responses to "agree/disagree" to declarative statements about selected product attributes include cooking quality, nutritiveness, availability, taste, keeping quality and comparison with soy flour. (Table 14). (Nyankory, J., 2001)

Table 14. Consumer preferences for cowpea flour attributes

In many areas of Africa fresh leaves are regularly harvested and consumed often as a part of the typical "sauce" (Bean/Cowpea CRSP West Africa Mission).

Cameroon

One recent outcome of CRSP research in Cameroon is the discovery of a sweet-tasting cowpea. One particular line, 24-125B, has been accepted by cameroonian growers because of its taste. Chemical analysis of "sweet" line at Purdue University revealed that it contained al least twice as much as sucrose as ordinary non-sweet lines. (Murdock, L and Nielsen, S.S., 2000)

1.6.1 Some cowpea recipes

Akara (Black-Eyed Pea Fritters)

In Western Africa, a popular way to eat cowpea is to make a batter from which fritters are manufactured. These fritters (known as accra, akara, akla, binch akara, bean balls, kosai, koosé, and kwasi) are commonly prepared at home for breakfast, for snacks, or as an appetizer or side dish. They are also fast food, sold by vendors on the street, in marketplaces, and at bus stations. This same recipe, with a very similar name, is also known in the Caribbean. Akara however, take at least an entire day to prepare, in order to allow the black-eyed peas to soak and the batter to rest.

What it is needed:

• two to three cups dried cowpeas (black-eyed peas) or similar

• one onion, finely chopped;

• one-half teaspoon salt;

• hot chile pepper, and/or sweet green pepper or sweet red pepper, finely chopped (to taste);

• one-half teaspoon fresh ginger root, peeled and minced (or a few pinches of powdered ginger) (optional)

• peanut oil, palm oil, or vegetable oil for frying.

What to do

• clean the black-eyed peas in running water. Soak them in water for at least a few hours or overnight. After soaking them, rub them together between the hands to remove the skins. Rinse to wash away the skins and any other debris. Drain them in a colander;

• crush, grind, or mash the black-eyed peas into a thick paste. Add enough water to form a smooth, thick paste of a batter that will cling to a spoon. Add all other ingredients (except oil). Some people allow the batter to stand for a few hours (overnight in the refrigerator); doing so improves the flavour;

• heat oil in a deep skillet. Beat the batter with a wire whisk or wooden spoon for a few minutes. Make fritters by scooping up a spoon full of batter and using another spoon to quickly push it into the hot oil. Deep fry the fritters until they are golden brown. Turn them frequently while frying;

Serve with an "african hot sauce" or salt, as a snack, an appetizer, or a side dish.

Moyin-Moyin

"Moyin-Moyin" (also called Moin-Moin, Moi-Moi), a sort of savoury bean pudding, is a unique and delicious way to prepare black-eyed peas or other beans. The traditional way to cook "Moyin-Moyin" is to wrap it in leaves (such as banana leaves) and steam it.

In modern Africa it is often cooked in empty tin cans, but it can also be made in muffin pans (muffin tins). There are many variations of "Moyin-Moyin". Skip all the optional ingredients to make a simple version; include one or more of the optional ingredients to make fancy Moyin-Moyin.

What it needed:

• two to three cups dried cowpeas (black-eyed peas) or similar

• one tablespoon dried shrimp powder

• one or two tomatoes, (peeled if desired), chopped -- or -- a similar amount of canned tomatoes -- or -- two tablespoons of canned tomato paste

• one or two onions, chopped

• salt and black pepper to taste

• chile pepper, chopped, to taste

• cayenne pepper or red pepper, to taste

• oil to grease muffin tin

• Optional Ingredients (a cup of one or more of the following):

✓ cooked shrimp, chopped

✓ cooked carrots, finely chopped

✓ sweet green or red pepper (bell pepper)

✓ hard-boiled egg

✓ dried, salted, or smoked fish; washed, cleaned and torn into small pieces

✓ canned sardines

✓ leftover cooked meat, cut into small pieces

✓ dried or smoked meat, torn into small pieces

What to do:

• clean the black-eyed peas in water in a large pot. Soak them in water for at least an hour or overnight. After soaking them, rub them together between the hands to remove the skins. Rinse to wash away the skins and any other debris. Drain them in a colander. If the beans have soaked only a short time, they may be cooked in water over a low heat until they are partially tender;

• crush, grind, or mash the black-eyed peas into a thick paste. Slowly add enough water to form a smooth, thick paste. Beat with a wire whisk or wooden spoon for a few minutes. A tablespoon of oil may be added. In a separate container combine all other ingredients and crush and stir them together until they are thoroughly mixed. Add the other ingredients to the black-eyed pea paste and stir to make a smooth mixture;

• grease the muffin pans (or tin cans). Scoop the "Moyin-Moyin" mixture into your pans (or cans), allowing some room for it to rise while cooking. Place the pans (or cans) in a baking dish partially filled with water. Bake in a medium-hot oven for about a half-hour. "Moyin-Moyin" in tin cans can also be steamed in a large covered pot on a stove. Check for doneness with a toothpick or sharp knife, as one would for a cake;

Un alternate cooking method is the following: Wrap the Moyin-Moyin mixture in banana leaves or aluminium foil to make small packets. Cook the packets by steaming them in a large pot, using a rack to keep them out of the water.

It may be served hot or at room temperature.

Koki

Koki (or Ekoki, Haricots Koki, Koki de Niébé, Gâteau de haricots, or Bean Cake) is popular all over Cameroon. It is made from cowpeas (niébé or black-eyed peas) or other beans (haricots). It is similar to the Moyin-Moyin of western Africa in that the beans are mashed into a paste, which is wrapped in banana leaves and steamed.

What is needed:

• two to four cups (one to two pounds) dry cowpeas (black-eyed peas), kidney beans, white beans, or similar

• one or two sweet peppers (red, green, or in between) and/or chile pepper, cleaned and finely chopped

• one cup palm oil

• salt

• banana leaves (or aluminium foil) and string

What to do:

• soak the beans in cold water overnight. Then clean and rinse them. If using cowpeas (black-eyed peas), it may be necessary to remove the skins, depending on the variety. Do so by rubbing the beans between the hands. Make sure the beans are clean, and then drain.

• crush, grind, or mash the black-eyed peas into a thick paste. Put the crushed beans in a large bowl. Slowly stir in enough water to make the paste smooth. Beat with a wire whisk or wooden spoon for a few minutes or more. It is important to incorporate small air bubbles into the paste.

• heat the oil in a skillet for a few minutes. When warmed, add half the oil to the bean paste.

• fry the chopped pepper in the remaining oil for a few minutes, then add pepper and oil to the bean paste. Add salt to taste and mix well.

• warm the banana leaves for a half-minute in a hot oven, or on a grill, or in a pot of boiling water. This makes them easier to fold. Remove the centre rib of each leaf by cutting across it with a knife and pulling it off. Fold the banana leaves to completely enclose the ingredients in a packet two or three layers thick.

• place sticks or a wire basket on the bottom of a large pot. (A stovetop steamer can be used.) Carefully stack the packets on the sticks, add enough water to steam-cook them. Cover tightly and boil for one to three hours. Cooking time depends on the size of the packet. The finished Koki should be cooked to the centre, like a cake.

Koki can be eaten hot or cold and is often served with boiled yam or sweet potato. To make the most authentic Koki, red palm oil is essential as it gives the beans the right flavour and colour. In rural areas of Africa fresh palm nut sauce (similar to Moambé/Nyembwe sauce) is often used instead of the refined red palm oil, which is available in cities.

Outside of Africa canned palm soup base, also called "sauce graine or noix de palme" can be found in speciality grocery stores and can be used in place of the red palm oil.

Koki can also be made from "cocoyam" (taro) tubers, which are cleaned, peeled and grated and substituted for the beans. Crushed dried fish or shrimp are often added along with the red palm oil.

Red-Red

"Red-Red", a popular dish in Ghana made from cowpeas (black-eyed peas), might be named for the combination of red pepper and red palm oil. The Red-Red cowpeas stew is usually served with fried plantains.

What is needed:

• two to three cups dried cowpeas (black-eyed peas) or similar

• one cup red palm oil (or vegetable oil)

• one or two onions, thinly sliced

• two or three ripe tomatoes, quartered

• one or two bouillon cubes or Maggi cubes (optional) or small piece of smoked or dried fish and/or one spoonful shrimp powder

• salt, cayenne pepper or red pepper

• several ripe or near-ripe plantains (but not overly ripe)

What to do:

• clean the black-eyed peas in water in a large pot. Soak them in water for at least an hour or overnight. After soaking them, rub them together between your hands to remove the skins. Rinse to wash away the skins and any other debris. Drain them in a colander. If using smoked or dried fish, remove bones and skin, rinse and soak in water, then dry. If using dried shrimp, grind the shrimp (or obtain already ground or powdered shrimp).

• place the black-eyed peas in a large pot, fill with water to just cover the peas. Bring to a slow boil, reduce heat, cover, and simmer until the peas are tender, thirty minutes to an hour. When cooked, the peas should be moist, but not standing in water;

• while peas are cooking, heat oil in a skillet. Fry the onions until slightly browned, then add tomatoes, and fish and dried shrimp (if desired). Mash and stir the mixture to form a sauce;

• stir the onion-tomato mixture into the black-eyed peas. Add Maggi cubes (if not using fish or shrimp). Simmer for ten minutes. Add salt, black pepper, and cayenne or red pepper to taste.

• While peas and sauce is simmering, prepare fried plantains.

Serve peas and plantains side by side on a plate.

Adalu

"Adalu" is cowpeas and maize. It is also called "Niébé et Maïs" or, in English, "black-eyed peas and corn". In Africa, it is usually made with dried cowpeas and either fresh or dried maize. It can also be adapted to use canned or frozen black-eyed peas and corn.

What is needed

• two to three cups (one to one-and-one-half pounds) dried cowpeas (black-eyed peas), or kidney beans, or similar

• one to two cups maize (corn), fresh, canned, frozen or dried

• a few small pieces of dried or smoked fish or ground dried shrimp (optional)

• one-half cup palm oil (or any oil)

• cayenne pepper or red pepper

• black pepper

•   small piece of potash, or dash of baking soda, or salt (to taste)

What to do

•   if using dried cowpeas (or beans) or dried corn. Clean and soak in water for a few hours or overnight, as needed. Rinse and drain;

• cook cowpeas in water in a large part until nearly tender (about an hour);

• add corn and other ingredients. Cook until cowpeas and maize begin to disintegrate and form a paste;

• season to taste.

Serve as a main dish or side dish. Without the fish or shrimp, "Adalu" can be served as a side dish with a West African soup such as pepper soup.

1.7 Others

Particularly in Africa continent and in developing countries cowpea post-harvest constraint are part of a broad chain of problems and limitants occurring in three following broad areas:

• abiotic: erratic rainfall, high soil temperatures, low soil fertility and degradated fragile soils;

• biotic: insect pests, parasitic weed, diseases induced by fungi, viruses and nematodes;

• socio-economic: resource-poor farmers are extremely risk-averse, farmer capacity to produce inputs is limited and input delivery systems function poorly.

To meet this situation enormous efforts have been made mainly in research activities. To date, cowpea research has been carried out by the West and Central Africa Cowpea Research Network (RENACO) in coordination with IITA. Funding was provided by the United States Agency for International development (USAID) through the Semi-Arid Foodgrain Research and Development in Africa Project.

There is also a cowpea research project that places priority on the development and dissemination of IPM technologies for cowpea. This project is being implemented by IITA and NARS and is funded by the Swiss Development Cooperation.

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