Nigerian has been chosen as a case study for new uses for cassava because it is the largest cassava producer and because its cassava transformation is the most advanced in Africa. We shall examine what needs to be done to increase the use of cassava in livestock feed and food manufacture: as starch in the textile, petroleum drilling, pharmaceutical, and soft drink industries; and as dried roots in the beer and alcohol/ethanol industries. This page is based on preliminary information collected in an exploratory survey in Nigeria in early 2001.

Expanding the Use of Cassava in the Livestock Industry

In Nigeria, the proportion of cassava used in the livestock industry increased after the government banned the importation of maize in 1985-86 and feed mills forced to use local raw materials such as cassava. After the import restrictions on maize and other crops were removed in 1985, there was no incentive for feed millers to reduce the quantity of cassava they were using, because cassava is cheaper than maize, the feed mills had modified their plants to mill dried cassava roots, and farmers were getting higher yields from TMS varieties. In Nigeria, the 5 percent of total cassava production that is used as feed is significantly lower than in Brazil (50 percent) because in Nigeria cattle, sheep, and goats are free grazed and pigs rummage on household waste. Also, the poultry industry has only 125 million birds in Nigeria, as compared with 867 million in Brazil in 1998 (FAOSTAT). Because of the pessimistic outlook for a major increase in the amount of cassava feed to livestock in Nigeria, the logical next step is to examine the global outlook for Nigerian cassava exports for livestock feed. The key country to examine is Thailand, because it has dominated the export of cassava pellets for livestock feed for more than three decades. In Thailand, only a small percentage of national cassava production is consumed as food. The most important uses for cassava are for livestock feed and starch.

Beginning in the 1960s, the government encouraged private firms to set up pellet factories and produce cassava pellets for export to the European Union (EU). The private sector responded, and pellet exports literally “took off”. In fact, export increased from 100,000 tons in 1966 to a peak of 9million tons in 1989. Yet because of competition with U.S. grain exports to the EU market, the price of cassava pellets has declined, making it unattractive for Thailand to produce cassava for export.  Also the EU has set an annual quota for Thai cassava imports of 5.25 million tons. However, because of low prices, Thailand did not meet its export quota from 1994 to 1998. In fact, pellet exports have declined from 9million tons in 1989 to 3 million tons in 1998 (Ratana waraha, Senanarong, and Suriyapan 1999, 18). There are currently two hundred palletizing factories in Thailand, with a total capacity of 10 millions tons per year. Yet because of depressed prices, they are operating at only 50 percent of capacity.

What is the outlook for Nigerian pellet export? Faced with over-capacity in pellet factories in Thailand and depressed world prices of cassava pellets, the answer is clear. Nigeria should concentrate on expanding the use of cassava in livestock feed at home rather than trying to break into the EU market at this time.  What can be done to increase the use of cassava in livestock feed in Nigeria? A poultry feed trial has shown that if cassava roots and leaves were combined in a ratio of four to one, the mixture could replace maize in poultry feed and reduce feed cost without a loss in weight gain or egg productions (Tewe and Bokanga 2001). If this important research finding is diffused and adopted by farmers and livestock feed producers, the amount of cassava used in livestock feed in Nigeria would increase and cassava leaves could become an additional source of income for cassava producers. At present, cassava leaves have no market value in Nigeria because they are not consumed as a vegetable as they are in the Congo and Tanzania.³

Expanding The Use of Cassava in Food Manufacturing

Technology exist for the use of cassava as a partial substitute for wheat in bread-making, and  biscuit, pastries, and snack foods manufacture (Satin 1988; Eggleston and Omoaka 1994; Defloor 1995; and Onabolu e tal. 1998). But in Nigeria in the late 1990s, an insignificant 3 tons of cassava was used per year for food manufacture compared with maize, 133,000 tons (FAOSTAT) .Use of cassava as a partial substitute for wheat in food manufacture will increase if the practice can result in a reduction in the prices of the manufactured composite cassava and wheat flour food products compared with prices of the same products made with 100 percent wheat flour. But in Nigeria, because of an array of reasons, the composite cassava and wheat flour food products are not cheaper than the 100 percent wheat flour food products. For example, a partial substitution of cassava for wheat in bread flour requires expensive supplementary viscosity enhancers such as eggs, milk, and gums to compensate for the lack of gluten in cassava (Eggleton and Omoaka 1994; Defloor 1995; and Onabolu et al. 1998).

Using cassava flour for bread-making and for the manufacture of biscuits, pastries, and snack foods requires a reliable supply of cassava floor with constant quality (Delfloor 1995). But in Nigeria, cassava flour available in the market varies widely in quality because of the wide range of traditional methods of preparation  used. A cassava flour of standard high quality will be more expensive and will increase the cost of the food products. Other important factors such as cassava variety, age of the cassava root, and the cassava growing environment also influence the quality of the food products in which cassava substitute partially for wheat flour (Eggleston and Omoaka 1994; Defloor 1995). Measures to standardize cassava varieties, age of cassava roots and the cassava growing environments will further increase the costs of the food products in which the cassava flour is used to substitute partially for wheat flour.

In  Nigeria, the technologies for the use of cassava as a partial substitute for wheat flour in food manufacture that were developed IITA and other research centers  were adopted by food industries when wheat flour was made scarce by the wheat import ban in the mid-1980s. But when the wheat import ban was removed in the mid-1990s. The food industries readily reverted to the use of 100 percent wheat flour in food manufacture (Bokanga and Tewe 1998).

In Nigeria, increase in the use of cassava in food manufacturing industries does not depend on technologies for partial substitution of cassava flour for wheat flour in bread, cookies, pastries, etc. But increase in the use of cassava in food manufacturing industries requires the development of technologies for industrial manufacture and packaging of traditional African cassava food products which have a snack value such as gari, attieke , and chickwangue.

We explained earlier that in Africa, past attempts to manufacture gari and chickwangue industrially failed because they were unprofitable. But in Brazil, recent development in the use of cassava in food industries shows that sustained investment in research and development can make industrial manufacture of a 100-percent-cassava-starch traditional food product profitable. For example, the main cassava-based fast food in Brazil is pao de queijo, a type of bread made with sour cassava starch, which has been fermented and dried (Vilpouz and Ospina 1999).

In Brazil, the preparation of pao de queijo by traditional methods has similar problems as the preparation of gari, attieke and chickwangue in Africa. For example, in Minas Gerais, one of the traditional  pao de queijo production states in Brazil, almost every family has its own recipe. Sour starch gives pao de queijo a very acid taste, which is appreciated in Minas Gerais state. In other states however, where consumption is more recent, people prefer pao de queijo with a mild taste. Industrial manufacture of pao de queijo needs standard product with consistent quality. These criteria are difficult to maintain in pao de queijo because of the low and unstable quality of sour starch. Making sour starch is labor-intensive. The sour starch industry is competitive with a large number of small producers. The small capacity limits the possibly to access modern technologies and market information (Vilpoux and Ospina 1999).

But through sustained investment in research and development in Brazil, pao de queijo was transformed from a small-scale homemade product to a large-scale factory-manufactured product by first replacing fermentation and sun-drying with a chemical process in making the sour starch. Later, the sour starch was replaced with other type of cassava starch that are acceptable to consumers. Since the early 1990s, the preparation of pao de queijo by small-scale manufacturers in the traditional production states such as Minas Gerais has been declining while larger more modern companies are expanding in other states. The entrance of large companies changed most  of the industry. The operators of the large companies have better education, better access to new technologies, and market information (Vilpox and Ospina 1999)

In Brazil, the research and development in the improvement of pao de queijo were carried out mostly by the private sector. But the expansion in the consumption of the pao de queijo was facilitated by political support. For example, the consumption was endorsed by the former Brazilian president, Itamar Franco. He required that pao de queijo be present at all official meetings. Since the mid-1990s, Brazilian consumption of pao de queijo has increased greatly, changing from a regional to a nation-wide fast food. It is also possible to find pao de queijo in other South American countries such as Argentina and Peru (Vilpox and Ospina 1999)

To summarize, there are technology for use of cassava as a partial substitute for wheat in food manufacture. Butt in Nigeria, cassava is not used for food manufacture because food products made with 100 percent wheat flour are cheaper and preferred by consumers. Brazilian examples show that sustained investment in research and development on industrial manufacture of African cassava food products such as gari, attieke, and chickwangue, which have snack value, can lead to increased use of cassava in food manufacturing industries.

Expanding the Use Of Cassava Starch As an Industrial Raw Material.

Plant starch such as wheat, rice, corn, potato, and cassava are used as an industrial raw material in direct form or in a number of derivative forms. We shall discuss using cassava starch in direct form, as hydrolysates, and as dextrins.

Starch in direct form.

In Nigeria in the early 1990s, only about 700 tons of cassava starch was produced per year because Nigeria cassava starch is considered to be of low quality by Nigeria industries and none is exported. By contrast, in the early 1990s, more than 1 million tons of cassava starch was produced in Thailand, 40 percent of which was exported because the quality was high (Ratanawaraha, Senanarong, and Suriyapan 1999, 14).

In Nigeria, the bulk off the starch used as industrial raw material during the late 1990s, 17,000 tons, was corn starch, which represented 82 percent of the total. In the late 1990s, cassava starch accounted for only 600 tons, or 3 percent, of the 17,000 tons of starch used each year as industrial raw material in Nigeria. The remaining 15 percent was an unspecified type of starch. The quantity of industrial starch used in Nigeria in the late 1990s was low. Even if most of it were made from cassava, the impact on the total demand for cassava would be small. One of the reasons is that industrial production in Nigeria declined in the 1990s. For example, the amount of starch used in the various industries was significantly higher in the late 1980s (33,tons per year) than in late 1990s (17,000 tons per year) (Raw Materials Research and Development Council 2000b, 5).The distribution of the total starch used in Nigeria was as follows: confectionary industry, 79.2 percent of total; automotive and dry cell battery, 6.1 percent; petroleum drilling, 5.5 percent; paint, 4.0 percent; textiles, 3.8 percent; and the remaining 1.4 percent in the pharmaceutical, iron ore mining, foundry, paper, soap and detergent, packing, and cosmetic industries. Nigeria 198 spinning, weaving, or finishing textile plants produced 300 meters of textile materials in 1992 (African Development Consulting Group 1997 2). The textile mills use mostly imported corn starch. The director of the Nigeria Cotton Mill (NCM) in Onitsha recently reported that the NCM has discontinued the use of Nigeria cassava starch because it was of low quality.

Cassava roots are often dried on the ground along the shoulders of highways, where they gather dust and mold. The starch industry should introduce a differential pricing system based on quality to induce small-holders to adopt better methods of drying cassava roots. There is potential for increased use of cassava starch as a raw material in the textile industry because Nigeria’s large population has a strong demand for African prints. In 1992, Nigeria textile mills exported 30 percent of their total production, and the export was valued at us $130 million (African Development Consulting Group 1997).

The Nigeria Starch Mill (NSM), Ihiala, the largest starch mill in Nigeria, produces cassava starch with dried roots purchased from small holders. In January 2001, the director of the NSM reported that he did not consider improving the quality of his product necessary because he was already able to sell all the starch he produced. Besides, if he invested in research and development to improve starch production technology, he would not have any patent protection.

Petroleum Drilling Industry.

 Starch is used as a clay dispersant in drilling mud in the petroleum industry (Balagopalan et al. 1988).There are two types of drilling mud; water-based and pseudo oil (synthetic fliud)-based drilling muds. The water-based mud is a mixture of water and starch, and it is used for drilling up to a depth of seven thousand feet . Beyond that depth, starch breaks down because of high temperature, and water based mud in replace with pseudo oil-based mud (Onwuta 2001). In Nigeria in early 2001, imported starch was being used in water-based drilling mud but other type of starch could be used if they gelatinize in cold water.The director of the Nigerian Starch Mill (NSM) was unaware that starch was used in oil drilling. He would like to sell starch to the oil industry but he is reluctant to invest in research to make cassava starch gelatinize in cold water because of the lack of  patent protection. There is a large potential for the commercial use of tropical starches such as cassava starch in the petroleum industry, but considerable research and product development are necessary in order to achieve this potential (Satin n.d.). since the oil sector supplies 95 percent of Nigeria’ foreign exchange earnings, investment in research to make cassava starch acceptable to the petroleum drilling industry could lead to a large increase in the demand for cassava.Nigeria has an oil reserve of 22.5 billion barrels and it is currently producing 2 million barrels a day (MBendi 2000, 1 and 2). 

Starch derivatives: Hydrolysates

When starch is subjected to an acid (usually sulphuric acid) or enzyme treatment, sweet substances called starch hydrolysates are produced: glucose, sucrose maltose, frutose, and syrup (Balagopalan et al. 1988,147 and 148). Starch hydrolysates vary in sweetness and viscosity depending on the degree of the acid or enzyme treatment and dehydration. They are use to impart sweetness, texture, body, and cohesiveness to drinks such as soft drinks, and to a variety of foods, such as soup, cake and cookie mixes; canned foods; and confectionaries. Starch hydrolysates are also a basic input in the manufacture of industrial chemicals such as alcohol, gluconic acid and acetic acid (Balagopalan et al. 1988). In Nigeria starch hygrolysates are used mostly in the soft drink and pharmaceutical industries.

The Soft Drink Industry.

 In Nigeria in the late 1990s, 174,000 tons of syrup concentrates were used in the soft drink industry to produce 33 million hectoliters of soft drink industry per year (Raw Materials Research and Development Council 2000c, 23).The soft drink industry is dominated by Coca Cola, which imports the syrup concentrates and keeps them as a trade secret. Nigeria’s soft drink industry imports all of its syrup concentrate because cassava starch is not currently hydrolyzed into syrup in Nigeria. In the early 1990s, however, an IITA post harvest technologist made syrup concentrate from cassava starch by treating it with sorghum enzyme. A pilot project is needed to test the suitability of cassava starch could be converted into syrup concentrate and replace imported syrup, it would open up a market for almost 1 million tons of cassava per year, or about 3 percent of current cassava production.

The Pharmaceutical Industry.

 The current annual use of starch hydrolysates in the pharmaceutical industry is as follows: glucose, 771 tons; sucrose, 750 tons; and syrup, 2 tons. At full capacity production, Nigeria’s seventy-seven pharmaceutical plants could supply  about 75 percent of Nigeria’s current pharmaceutical needs. Yet Nigeria’s  plants are operating at about 35 percent of  their capacity because of a lack  of basic raw materials (Raw Materials Research and Development Council 2000b, 13). Currently, 80  percent  of the material used by the pharmaceutical industry is imported, because the basic chemicals  and petrochemical  industries are not developed in Nigeria  (Raw Materials Research and Development  Council 2000b, 12). The Raw Materials  Research and Development Council  (RMRDC) observed that “any reasons that can be advanced for the slow pace of industrialization in Nigeria can be reduced to one single fact: for now it is easier, less risky, and much less complicated to impact than to manufacture” (RMRDC 1997,41).

Starch Derivatives: Dextrins

Dextrins are produced by heating starch in a dry form with acid or alkali as a catalyst ( Colonna, Buleon, and Mercier 1987, 110). Dextrins are sold as powders, granules, and pastes. Adhesives are made by cooking a dextrin in water. Adhesives are used in making corrugated boxes, sealing cartons, grocery bags, and multiwall bags in the packaging industry; for lamination in the  plywood, paperboard, footwear, and cables industries; in the production of paper tubes, cans, and cones; as printing, publishing, and library paste; and as label adhesive for envelopes, postage stamps, gummed tapes,satety matches, and many other items.

            In the late 1990s,an average of 58,000 tons of adhesives were used per year in the following industries  in Nigeria: wood, 44 percent; cable,26 percent; paper, printing, and publishing ,15 percent; packaging,14 percent; and matches and footwear, 1 percent.¹²   All the adhesives used in Nigeria in the late 1990s were imported either as adhesives or dextrins. If all of the adhesives used in Nigeria  had been derived from cassava, about 60,000tons of cassava representing  0.2  percent of Nigeria’s current production, would have utilized.

Beer Malt: A New Use for Dried Cassava Roots

Beer has been brewed in Nigeria with imported barley malt for many decades. However, in 1985-86 Nigeria banned grain  imports and the brewery industry began to produce beer malt sorghum produced in Northem  Nigeria. The initial concern that sorghum beer would not be acceptable to consumers proved to be without basis, as beer consumption did not decline after sorghum malt  was used  to replace barley malt. In the late 1990s, about 11 million hectoliters of beer were being produced  per year in Nigeria (Raw Materials and Development Council 2000c,23).

            Although cassava is produced in Southerm Nigeria, where all of the beer breweries are located, no attempt has been made to   produce beer malt with dried cassava roots, even though dried roots are cheaper (US$79 per ton)  than sorghum (US$139 per ton) (Ogazi, Hassan, and Ogunwusi 1997, 31and 77).13 A biochemist of the National Root Crops Research Institute (NRCRI)  at Umudike  reported in early 2001 that beer malt could  be made with any starch, provided the right of enzymes are available.14 Research is now needed to determine the type and quantity of enzymes needed for marking beer malt from dried cassava roots. However, the  NRCRI is unable to carry out the needed research because the operational budget for its research unit  is only a few hundred dollars per years.

            The manager of the Golden Guinea Brewery, Umuahia believes that consumers would accept cassava malt beer, judging form their ready acceptance of sorghum  beer in the mid.15 However, the manager reported that Golden Guinea would be reluctant  to invest in research  on making beer malt from cassava roots because patent law is not enforced in Nigeria.

            In early 2001, the manager of the Life Beer Brewery in Onitsha  reported that Life Beer  is made directly from sorghum without malting at the rate of 9 tons of sorghum per 500 hectoliters of beer.16  Using this ratio, the beer industry in Nigeria consumed about 200,000 tons of sorghum per year in the late 1990s. If dried cassava roots had replaced sorghum, the beer industry would have consumed 220,000 tons of dried cassava roots, which is more than 2 percent of annual cassava production  in the 1990s. Research  is needed on how to make beer malt  from  dried cassava roots because even a partial  substitution  of  dried cassava  roots  for sorghum in the beer malt will reduce the cost of  beer production, increase employment in the beer industry, and raise the income of cassava farmers.

Developing a Cassava- Based Alcohol/ Ethanol Industry

In the late 1990s, 78 million liters of alcohol were used each year  in Nigeria by the liquor industry and 10 million liters by the pharmaceutical industry. Virtually the whole of the alcohol used in Nigeria in the late 1990s was imported, because domestic production was insignificant. For example, in 1998, the total production from Nigeria’s sole ethanol plant was only 200,000liters (Bamikole and Bokanga 2000).

            In 1963, the Nigerian government set up a sugar plant,  the Nigerian Sugar Company (NISUCO) to produce sugar from sugar cane. Ten years later, the government set up the Nigerian Yeast and Alcohol Manufacturing Company  (NIYAMCO) as an annex to NISUO with a goal of producing ethanol with molasses. Although NIYAMCO had an installed capacity of 4 million liters of ethanol per year, the supply of molasses began to decline in the early 1990s because of the collapse of the government –owned sugar plantation, which supplied sugar cane to NISUCO. In 1994,NIYAMCO began looking for an alternative source of material. With IITA’s technical support, dried cassava root was selected as a raw material for the manufacture of ethanol by the NIYAMCO because cassava is abundant in Nigeria, has a high starch content, and as a low gelatinization temperature (Bamikole and Bokonga 2000). NIYAMCO required only about 30 tons of dried cassava per day but because of problems of organizing the collection of dried cassava from scattered small holders, NIYAMCO closed its ethanol plant (Bamikole and Bokonga 2000). If the 88 million liters of alcohol currently imported each year for the liquor industry were produced with cassava root in Nigeria, it would open up a market for about 600,000 tons of cassava roots, or about 2 percent of national cassava production during this period.

In the United States, the Clean Air Act Amendment of 1990 mandated the sale of oxygenated fuels in area with unhealthy of carbonmonoxide. Since that time, there as been strong demand for ethanol as an oxygenate blended with gasoline. In the United State, more than 1.5 billion liters of   ethanol is added to gasoline each year. Ethanol is blended with gasoline to form an E 10 blend (10 percent ethanol and 90 percent gasoline) (Alternate Fuels Data Center 2000,1). Major automobile manufacturer also have models that can operate on an E 85 blend (85 percent ethanol and only 15 percent gasoline) (Alternate Fuels Data Center 2000, 3). Fuel ethanol blends are successfully used in all types of engines that require gasoline. However ethanol production is subsidized in the United States.

The dynamic growth of Brazil’s ethanol industry may awaken African policy makers and entrepreneurs to an opportunity for increased cassava production and utilization in cassava-based ethanol or production. The story of the Brazil’s ethanol industry began in 1931, when the government enacted a decree that called for the addition percent ethanol to imported gasoline in other to find a market for Brazil’s ailing sugar cane industry. Almost forty-five years later, in 1975 the government introduced the Brazilian National Alcohol Program to reduce the imported crude oil bill by increasing the percentage of ethanol in gasoline from 5 percent (Lindeman and Rocchiccioli 1979; Pimentel 1980). To realize this goal, the Brazilian government set up two research and development agencies, the Technology Alcohol Program and the Sugar and Alcohol Institute.

The new agencies explored the source of various raw materials and found that of the sources available, “the most important by a wide margin was a cassava root… It was evident that cassava was a very viable alternate source for ethanol”(Lindeman and Rocchiccioli 1979,1108 and 1109). The yield of alcohol per ton is higher from cassava (150 liters per ton of fresh root) than from sugar cane (48 liters per ton) (Balagopalan et.al 1988,182). A much lower quality soil is required to produce cassava than sugar cane, and a distillery using cassava to produce alcohol can operate year-round. By contrast, a distillery based on sugar cane as a raw material must stand idle for several months a year when sugar cane is not available (Lindeman and Rocchiccioli 1979). Brazil’s research and development agencies compared sugar cane and cassava and selected sugar cane to produce ethanol because sugar cane was an old and traditional crop that was cultivated on a large scale throughout the country. Sugar cane varieties in Brazil were nearly all hybrids that had been developed by the national experimental stations, except for a few obtained from India and Argentina (pimental 1980,2002).

Turning from production to processing sugar cane, research in Brazil showed that there was a great potential for small-scale alcohol processing unit for developing countries (Balagoplan et al. 1988). However, Brazil opted for large units, because sugar cane, the chosen raw material source, is produced on large plantations. Another challenge was what to do with the expected large amount of ethanol and sugar industrial wastes such as stillage and bagasse The research agencies recommended recycling stillage as fertilizer for sugar cane production and using bagasse to generate electricity for the ethanol plants (Pimentel 1980 and Green Times 2000)

Brazil’s learning-by-doing approach yielded positives results. Ethanol production grew from a mere 0.6 billion liters in 1974-75 to 14.0 billion liters in 1988-89 (Lindeman and Rocchiccioli 1979,1111; Green Times 2000,1). Brazil was able to achieve this level of success in ethanol production because large-scale sugar cane producers responded positively to the expanding market for ethanol: the area of sugar cane harvested increased from 1.9million hectares per year in the early 1970s; yield to 4.9 million hectares per year in the late 1990s; yield increased from an average of 46.7 tons per hectares in the early 1970s to an average of 68.1 tons per hectares in the 1990s; and total production increased from 89 million tons per year in the early 1970s to 331 million tons per year in the late 1990s (FAOSTAT). In the year 2000, one million people were working in Brazil’s sugar-ethanol sector, including three hundred thousand in 350 private ethanol units and fifty thousand sugar cane growers (Green Times 2000,1).

Based on research in Brazil, Nigeria and other cassava-producing African countries may be able to produce ethanol or alcohol with small-scale cassava-based production units (Balagoplan et al. 1988). Although Nigeria could theoretically benefit by using cassava to produce alcohol and replace alcohol imports for alcoholic beverages, public enterprises such as the NIYAMCO and NISUCO have floundered in Nigeria because of mismanagement of public resources and the inability of the government to provide research and development support to assist new industrial enterprises. However, a cost-benefit study ethanol production should be completed in petroleum-importing Ghana. A cassava-based ethanol industry could reduce the petroleum import bill for major cassava-producing and petroleum-importing African countries such as the Congo, the cote  d’Ivoire, Ghana, Tanzaia, and Uganda.

(CULLED FROM CASSAVA TRANSFORMATION BY NWEKE &OTHERS)