2
CASSAVA FLOUR

Global Perspectives

Import substitution opportunities for cassava exist in three broad areas - (i) cassava flour, (ii) cassava starch and (iii) animal feed. Cassava flour can be used as a partial replacement for many bakery and pasta products. The process of making cassava flour entails peeling and washing, grating, dewatering, pulverizing, drying and milling.

Cassava flour can be used as a partial replacement for imported wheat flour. As can be seen in Table 11 all regions experienced substantial increases of wheat imports in the 'sixties. Since 1970 growth in wheat imports has been relatively stable except for the sharp increase for Oceania. Per capita wheat imports in 1995 for Latin America and Oceania exceeded cassava consumption. The form of wheat imports varies from country to country. Some countries import wheat flour while other countries import wheat and mill the flour domestically.

As an initial estimate of the wheat and wheat flour import substitution opportunity for cassava flour, it is assumed that 10 percent of current wheat and wheat flour imports could be replaced. (Note that 10 percent is lower than most cassava flour substitution rates used, or recommended in the case studies that follow). It is further assumed that one tonne of cassava flour requires four tonnes of roots. Applying these assumptions to current wheat and wheat flour imports produces Table 12.

The results suggest that replacing wheat imports with cassava flour could regionally increase the demand for cassava by more than 10 percent in all regions, except Africa. The last column is the average price of wheat imports. By way of a simple comparison the import price sets a target for the price of cassava flour. Given the assumptions stated above, the implicit price for a tonne of cassava roots plus transportation and processing range from US$36 to US$63.

When the analysis is applied at the country level, one can see that as many as 23 countries could realise at least a 20 percent increase in the demand of cassava, as a 10 percent substitute for imported wheat and wheat flour (Table 13). A majority of these countries are in Latin America. In Africa Senegal, Somalia and Zimbabwe would appear to be the main benefactors. In Asia China, Sri Lanka, Malaysia, Myanmar and Philippines would appear to be the main benefactors. For many of these 23 countries the "target" price for cassava is greater than US$50 per tonne. Based on some of the case study information reported in subsequent case studies, this target price would appear to be sufficient to promote the use of cassava as a partial substitute for wheat.

Cassava as a wheat flour substitute in Ghana

Status of the wheat market

Increasing urbanization has led to a rapid increase in the market for convenience foods such as bread, biscuits, pies and cakes in Ghana. All of these products contain a significant amount of imported wheat in the form of flour. Since 1980 there has been an upward trend in the amount of imports of wheat equivalents (Table 14).

In the 'nineties Ghanaian wheat imports were as high as 300 000 tonnes (Graffham et al 1997). The vast majority of this is milled locally by one of Ghana's four main wheat millers (Table 14). Formerly the wheat market in Ghana was closely controlled by the Government but following liberalisation, the millers have been able to source wheat independently on the world market.

The continued depreciation of the Ghanaian Cedi against the US Dollar coupled with increases in US Dollar prices for wheat on the world market has led to sharp increases in the price of wheat flour in Ghana. In March 1995 the wholesale price for 50 kg of wheat flour was 21 000 Cedis; by mid-March 1996 this had increased to 38,725 Cedis per bag. A further increase to 42 000 Cedis for white bread flour was reported in April 1996.

In October 1997 the wholesale price for 50 kg of wheat flour was 58 000 Cedis. These increases reflect unavoidable economic problems as it is recognised that the wheat flour market is not truly competitive and is likely to be influenced by the political wish to keep prices of food staples low.

Local alternatives to wheat flour

Increasing prices and currency devaluation have encouraged food manufacturers in both the formal and informal sectors to look for local alternatives to wheat flour.

Given the ready availability of cassava in Ghana, and the existence of suitable processing technologies, cassava flour would appear to be an obvious choice as a partial substitute for wheat flour. However, manufacturers of food items expressed concern over the quality of cassava flour and consumer acceptability. From past experience, manufacturers associated the name "cassava flour" with poor quality fermented products having a low pH, unpleasant taste, odour and colour. Some manufacturers were concerned that cassava flour would lead to toxicity problems due to the presence of cyanogenic glucosides (Day et al. 1996).

Since 1996 the Natural Resources Institute in collaboration with the Food Research Institute (Ghana) and University of Ghana have been working with biscuits manufactures and several small bakeries in Accra. Together they are working to demonstrate that high quality cassava flour can be produced at an economic price, and incorporated in common snack food items such as biscuits and cakes. The project is to demonstrate also that products containing cassava flour will be acceptable to consumers in a wide range of socio-economic groups. Market acceptability studies in Greater Accra showed that consumers would accept substitution levels of 35% cassava flour in sweet dough biscuits and 60% cassava flour in hard dough biscuits. However, bakers would never go above 50% in hard dough biscuits because of problems of brittleness with products containing high levels of cassava flour (Ababio 1998).

The project has looked at a range of processing methods for peeled roots of locally available low cyanide varieties, including chipping and grating and sun and artificial drying. All methods gave flours of similar quality but grating resulted in a much higher microbial loading than chipping. Sun-drying greatly reduced the cost of production but increased drying times and risk of spoilage due to changes in weather conditions (Grantham and Dziedzoave 1998) and (Ababio 1998).

Although no formal specification exists for unfermented high quality cassava flour in Ghana, biscuit manufacturers and small bakers involved with the project have defined their requirements (Table 15).

This renewed interest in cassava flour as demonstrated by the above-mentioned project, is owing to economic factors, although it would be true to say that improved road infrastructure has increased the potential for development of a processing industry, to supply locally produced cassava flour to potential users in urban areas.

Constraints to wheat flour substitution

The likely physical bottlenecks include access to consistent supplies of high quality cassava, transport and lack of power for processing equipment. However, the results of the analysis presented in the beginning of this Chapter suggest that only a small percent of current cassava production needs to be devoted to the wheat replacement market. Thus the physical bottlenecks relate primarily to the quality of cassava, transportation and processing.

The major economic determinant influencing this opportunity is the rising cost of wheat flour set against the potential to produce cassava flour at a lower price. In production trials cassava flour was produced for between US$0.13/kg and US$0.22/kg depending on whether sun or oven drying was used. This compared favourably with the wheat flour price of US$1.30/kg. Small bakers are producing sweet dough biscuits that use 0.5 kg of wheat flour per kilo of biscuits, thus giving a wheat flour cost of US$0.65. When cassava flour was used to substitute for 35% of the wheat flour, a cost saving of 32% was achieved.

The level of investment required to develop this opportunity will vary between US$2 000 and US$20 000 depending on what type of drying method is employed and whether chips are produced in the field or at a centralized processing site.

This opportunity is likely to be affected by economic factors such as macroeconomic and infrastructure problems affecting end users, raw material price and access to credit to support farmers and primary processors wishing to exploit this opportunity.

To be successful this opportunity requires active support from the potential users of cassava flour who need to demonstrate that a market exists for the product, and to set standards for production. Currently many prospective processors of cassava flour are reticent about taking up production because it is believed with some justification that the food sector will be unwilling to use cassava flour in its products.

High quality cassava flour has been shown to have both the technical and economic potential to succeed in Ghana as a partial substitute for wheat flour in food products. However, it is unlikely to succeed in practice without considerable promotion and an enabling environment.

Cassava as a wheat flour substitute in Nigeria

Preparation of flour is one of the traditional ways of preserving and adding value to cassava roots that is practised widely in Africa (Natural Resources Institute 1992). However, cassava flour prepared using traditional methods is often fermented and frequently of poor quality, thus making it unsuitable as a substitute for wheat flour in bakery products.

Current status of wheat and wheat flour imports

A combination of increased urbanization, rising incomes, market promotions and specific policy decisions favoured the importation of large amounts of wheat into Nigeria between 1960 and 1987 (Bokanga and Djoussou 1998). In 1985 Nigeria was the largest importer of wheat in Africa with imports totalling US$37 million that accounted for 2.2% of the nation's foreign exchange earnings (Djoussou and Bokanga 1997). By 1995 the value of wheat and wheat flour imports exceeded US$293 million (FAOSTAT).

Between 1987 and 1990 the Federal Government of Nigeria banned importation of grain thus drastically reducing consumption of wheat products. According to Djoussou and Bokanga wheat imports recovered when the ban was lifted but overall the trend for wheat imports into Nigeria is one of decline. They attribute the decline in wheat imports to a combination of high prices for imported foods including wheat and wheat products, currency devaluation and a continual fall in real per capita incomes. These circumstances have created a favourable environment for the development and adoption of cheaper locally produced alternatives to wheat flour.

Local alternatives to wheat flour: The IITA contribution

The International Institute for Tropical Agriculture (IITA), Ibadan (Nigeria) minimised the capital investment requirements for flour production by developing a method that makes use of equipment used for gari preparation (Onabalu and Bokanga 1998). The IITA process is summarized in Figure 4. This technique was shown to be suitable for preparing cassava flour from both sweet and bitter varieties of cassava.

Mini chippers were also tried in place of the mechanical grater but were found to be unsuitable for bitter varieties because of insufficient reduction in the concentration of cyanogenic glucosides during processing (Abass, Onabalu, and Bokanga 1997) and (Onabalu and Bokanga 1998). Under optimal conditions (dry sunny weather for sun drying), the IITA technique enables small-scale primary processors to produce high quality unfermented cassava flour that meets industrial users' specifications (Table 16) within one day.

The practical standard for edible flour established by several biscuit manufacturers in Oyo State, Nigeria shown in Table 17 is less sophisticated than the international standard for edible cassava flour defined by (FAO 1995). However, the Nigerian specification gives a better indication of the practical requirements of users. The Table evidences that manufacturers of bakery products in Nigeria are mainly concerned with acidity, gross contamination and cyanide rather than microbiology or specific pasting characteristics.

The dissemination phase of the IITA project commenced in December 1994 with the training of 77 women and 3 men who were involved in processing of cassava or preparation of bakery products in Oyo town. In February 1995 a commercial biscuit manufacturer commissioned the trainees to produce an initial batch of high-grade cassava flour for use in product development. By 1997 three biscuit manufacturers, two bread bakeries and several small producers of snack foods had placed regular monthly orders for cassava flour to use as a substitute for wheat flour. A fourth biscuit manufacturer was in the process of product development in 1997. During the same period, IITA provided training to 900 primary processors wishing to manufacture cassava flour. Initially cassava flour sold for 10 Naira/kg but the biscuit manufacturers rapidly established a quality standard with pH as the key factor. To encourage quality the biscuit manufacturers established a system of price premiums based on pH (Table 17).

By late 1997 the price for premium quality cassava flour was 30 Naira/kg for a production cost of 20-30 Naira/kg (US$0.91-US$1.37) depending on fluctuations in price of cassava roots. Cassava flour can reduce a food manufacturer's bill for flour by as much as 48-50% depending on the degree of substitution. Primary processors normally operate in groups of 14 who share processing equipment. In Oyo State these groups contract directly with the users of cassava flour. According to (Abass, Onabalu, and Bokanga 1997) eleven groups of processors were active in 1997. Seven of these used graters for flour production, one group used a mini chipper and the remaining three groups had access to both graters and chippers. During the dry season a processing group can produce 1 000-2 000 kg of cassava flour. In the wet season this falls to 100-1 000kg per week (ibid). Using these figures an individual group member could expect to make a maximum of 714 Naira per tonne of cassava flour (US$32.62) and a maximum income of 1,428 Naira per week (US$65.24) depending on level of production and cost of raw material.

Although cassava flour can theoretically be used to substitute for 100% of wheat flour, Nigerian food manufacturers have determined practical limits for a range of food products (Table 18).

The major physical bottlenecks for the IITA process are access to processing equipment, power to provide mechanization and reliance on good weather for drying the product. In the Nigerian case, weather appears to be the major bottleneck. It can reduce production rates by 90% and interfere with delivery and reductions in product quality and sale price. Prolonged drying leads to fermentation of the wet mash and a reduction in pH value.

Factors underlying the Nigerian growth opportunities

The success of high quality cassava flour as a partial substitute for wheat flour in Nigeria has been mainly due to economic factors and changes in government policy. As long as wheat was readily available at low cost it remained the favoured raw material for bakery products in Nigeria. The ban on importation of cereals between 1987 and 1990, created an environment where manufacturers were forced to look at alternatives to wheat, to remain in business regardless of quality and other technical difficulties. Experience gained during this period has led food manufacturers to more readily accept cassava flour as a cheaper alternative to wheat flour if processors can provide the necessary quality. In the post-ban period Nigeria's economic difficulties, currency devaluation and falling per capita incomes have all helped to maintain interest in cassava flour as a means of continuing to produce competitively priced products. It has been estimated that a reduction in wheat flour imports of 15% through substitution with cassava flour could save Nigeria US$14.8 million per annum in foreign exchange (Djoussou and Bokanga 1997). The net return to processors from this saving would be in the region of US$12.7 million and cassava farmers could expect to receive a gross benefit of US$4.2 million. Thus cassava flour market opportunity has been mainly influenced by changes in national policy and economic factors but has also been influenced by other factors. These factors include the existence of food processing industries, the ready availability of cassava, the ready access to suitable processing equipment and the acceptance of cassava as a convenience food (as gari) by urban and rural consumers.

Production of cassava flour is a relatively simple procedure requiring access to small amounts of clean water for root washing, and a number of items of processing equipment (Table 19). A group of 14 processors would require between US$1,780 and US$2,750 depending on the type of equipment used to produce high quality unfermented cassava flour for human consumption independently. These costs could be reduced if the group could gain access to a central mill facility equipped with hammer mills and possibly mechanical graters as well, or by using a belt drive to power the grater and mill from a single engine.

Product substitution constraints

The primary economic constraint affecting this market opportunity is high raw material costs, which can make production of cassava flour uneconomical. Another constraint is the lack of capital available to primary processors for investment in additional items of machinery for production of cassava flour.

The stakeholders in this system are cassava farmers, primary processors and end users of cassava flour. The end users have an important role to play in this system as they provide demand for the product, set quality standards and offer incentives for production of consistent quality. In some cases biscuit manufacturers have collaborated with local NGOs to provide training and support for the primary processors in aspects of quality control and business management. As in the other case studies, the processor provides a means for cassava farmers to obtain access to a wider market for their products.

Continued support is required from both government and NGOs to promote the use of cassava flour as a substitute for wheat flour. Their support is also necessary to provide training and financial assistance for primary processors wishing to exploit the market opportunity. In the present case IITA have found that soft loans of US$2 000 shared between three groups of processors were sufficient. Processors were normally able to pay back the loans over a 12-18 month period. In the Nigerian case, processors normally had access to most of the equipments required. In countries lacking an established processing industry with the relevant equipments, higher levels of loans would be required.

Lessons from the Nigerian experience

Cassava has advantages as a raw material for flour production because of the ease of processing and low capital investment required in establishing a processing unit. In addition cassava flour has a bland flavour and is thus unlikely to alter the flavour of any product in which it is used. The example from Nigeria appears to have potential for replication elsewhere. The following factors are likely to be important for the success of this opportunity:

Positive environment: There must be a positive economic and policy environment for adoption of cassava flour as a substitute for wheat flour.

Consumer acceptance: Users and consumers must be willing to accept cassava flour in food products.

Reliable supply: Primary processors must be able to provide a reliable supply of cassava flour of a consistently high quality at a competitive price.

Competitive price: Cassava roots must be available at a sufficiently low price to undercut imported wheat.

External support: Government and NGO support needs to be available to promote the acceptability of cassava flour and provide training, financial and technical support to primary users.

Access to machinery: The success of the Nigerian example was assisted by the fact that it utilised machinery available for processing another product (gari). The same situation may or may not exist in other countries.

Future directions

The import substitution potential of cassava flour for wheat has long been recognized. However the past availability of wheat and wheat flour as food aid and national policies, such as overvalued currency, has worked against the development of a domestic cassava flour industry. The global analysis at the beginning of this chapter makes a case for the growth opportunity that could result from using cassava flour as an import substitute for wheat and wheat flour. In the case of Asia and Latin America the wheat flour substitution market could be equivalent to an additional 13 and 11 percent of current production respectively. The collective potential impact on the African countries studied is only one percent. When the analysis was carried out at the country level 23 countries were identified as having the possibility of developing a new market that would be equivalent to at least 20 percent of 1995 production. The analysis suggested that the price for cassava roots, processing and transportation could probably be greater than US$50/mt.

Even though the country level analysis did not indicate great potential for the cassava flour market in Ghana and Nigeria, a closer examination of the situation indicated that this market is very promising. Both Ghana and Nigeria, owing to changes in national policies and international prices, are finding cassava flour to be an attractive replacement for wheat and wheat flour imports. The use of cassava flour is more advanced in Nigeria than in Ghana. In both countries further expansion of the markets will require a reliable supply of cassava flour of a consistently high quality at a competitive price. Fortunately the technology to produce cassava flour is simple and easily applied in the two countries. The major bottleneck would appear to be the rapid drying of cassava, throughout the year. This is an area that could benefit by further research and development.

One should not underestimate the benefits of using cassava flour as a wheat flour replacement. As noted in the Chapter, a 15 percent replacement of wheat flour imports could equate to an annual foreign exchange savings of US$14.8 million. Within the country net returns to processors could be US$12.7 million and cassava farmers could expect to receive a gross benefit of US$4.2 million. Clearly more countries need to examine the potential benefits of replacing wheat and wheat flour imports with cassava flour. As international trade agreements are reached which will probably reduce the availability of wheat as a food aid item and increase the world price of wheat and wheat flour, the benefits of using cassava flour should increase.