Cassava: A BioFuel

By Godfrey Eneas

Cassava has become an important biofuel crop. Apart from its traditional role as a food crop, Cassava has increased its value as a fuel commodity. The following article highlights the variety of uses the cassava has. In recent years cassava imports have been increasing as a result of the large Haitian population in The Bahamas. In the Haitian diet, cassava is an important source of starch.

The technology for converting cassava into the biofuel Ethanol is being perfected and, in time that technology could be used here to convert Bahamian grown cassava into Ethanol.

Booming outputs meet flagging markets
The economic potential for cassava — a crop crucial for food security, especially in Africa — remains largely untapped, despite constant growth in output. Nevertheless, a range of markets, including consumer, industrial, local and international, are important as this tuber strives to become competitive.

Which crop grown in Africa produces twice as much as maize and three times as much as millet or sorghum? And which crop has seen Africa emerge as overall leader, accounting for more than half of the world output, with Nigeria as the biggest producer? Which same crop has seen production levels triple on the continent over the past 50 years? And now covers one-third of the dietary needs of its population? The answer is cassava. In the past few decades, this tuber has quietly taken over thousands of hectares and become the staple food of over 200 million Africans, or more than one-quarter of the continent’s population.

According to FAO figures, Africa produced 103 mt of cassava tubers on 18 million ha of land in 2004. This shrub, with its long stems and parasol-shaped leaves is now as common in Sahelian countries as it is in the more humid climes of Central Africa and the Gulf of Guinea, where it has traditionally thrived. Output varies greatly between regions, ranging from 1.8 t/ha in Sudan to an average of 10.6 t in Nigeria (which still falls way behind the yields achieved in the Caribbean: 16.6 t in Barbados alone). Well established in countries such as the Democratic Republic of Congo (DRC), which for a long time was Africa’s leading producer, the crop has now spread to southern Africa (Malawi, Zambia) at the expense of maize. Here, where HIV/AIDs is killing many farmers, families are turning to crops which require less labour.

Insuring against famine
A number of other factors explain this rapid expansion, especially on smallholdings run by poor farmers, where cassava is often grown together with other crops. Cassava has the advantage of being relatively undemanding, and will thrive on poor and even tired soils, where few other crops will grow. In places where land is scarce, it also serves as food security for many villagers vulnerable to malnutrition. With cassava, they can be more confident of having a low-cost, plentiful supply of calories than they would have had they grown cereals. For farmers living close to towns, it is a valuable cash crop, with a flourishing market. In West Africa, its development has been further helped by the rapid expansion of towns and by an initiative launched by the International Institute of Tropical Agriculture (IITA), which has distributed new, more productive varieties that are resistant to a number of diseases as well as to drought.

Cassava, fuel of the future?
At a time when oil prices are soaring and global reserves dwindling, the spotlight is turning to ethanol made from fermented cassava starch, a particularly promising resource. Similar to other types of ethanol obtained from agricultural products, it can be used to substitute between 10% and 25% of petrol in vehicles with standard engines, and up to 100% in vehicles whose engines have been adapted.

Brazil, the world’s leading producer of these substitute fuels or biofuels, makes more than 120 million hl per year from sugarcane and cassava. In Thailand and China, several projects for manufacturing cassava-based biofuel on an industrial scale are under way. In Africa, Nigeria is following suit and in early 2006, a law is expected to approve the use of 10% biofuel in petrol, thereby cutting both the country’s oil bill and pollution levels. In the short term, the fuel will be imported from Brazil, but in the longer term it will be manufactured locally.

The flip side of the coin is that when this crop — vitally important to a number of regions — is hit by disease, the result is famine. That was seen all too clearly when the cassava mosaic virus devastated production in Uganda during the 1990s. Burundi, DRC and Rwanda are currently grappling with the same disease and programmes to distribute resistant varieties are attempting to curtail the epidemic before it takes hold.

This plant has long been neglected by research in favour of cereals, but its recent rapid success and its key role in feeding a number of regions go a long way towards explaining the renewed attention it is enjoying today. In partnership with the IITA, The New Partnership for Africa’s Development (NEPAD) has launched the Pan-African Cassava Initiative to encourage projects based on “the use of cassava as a food security crop and as a weapon against poverty”.

However, the economic importance of cassava is still disproportionately low given the major role it plays in agriculture and food supply. Once the hydrocyanic acid has been removed from the bitter varieties, the edible leaves are rich in protein and the tubers lend themselves to a wide range of preparations: chips, flour, semolina and cassava meal (gari, attiéké, foufou, chikwangue) to name a few.

According to the IITA, close to one-third of all cassava is eaten fresh. The remainder needs to be processed quickly, as the tubers keep for barely 2 days under normal storage conditions. The Collaborative Study of Cassava in Africa (COSCA), conducted in the 1990s, found that only 20% of cassava-producing villages can be reached by motorised transport. Generally, farmers have to travel more than 10 km to take their heavy loads to market. In DRC, Africa’s second largest producer, that is the case for seven out of ten villages.

Long preparations
Before cassava can be conserved and sold, it must first be processed. This task generally falls to women, who soak and grate it, then dry the roots. It is a long and tedious job, especially in rural areas where there are no machines, and the high input in terms of labour is not reflected in the often low price fetched by the finished product. Small businesses equipped with machinery are springing up in some towns, especially in countries around the Gulf of Guinea, and this encourages a steady flow of production from farmers in the outlying areas. COSCA has estimated that a mechanical grater cuts the processing time by half and therefore increases profits. In West Africa, the IITA has developed and distributed a number of machines, but they are still not sufficient, especially in the villages, to increase the commercial viability of a sector which in any case suffers from poor organisation.

Beyond production
Between 1996 and 2003, cassava production doubled to reach a total output of 3.9 mt in Benin, while the per-ha yield increased by 25%. This strong performance was largely the result of the government scheme “a billion for cassava” which offered credits, fertiliser and cuttings of improved varieties to producers in a bid to encourage them to increase production. But nothing was done to improve marketing at the same time.

Poorly organised and lacking in processing equipment, the cassava sector proved unable to absorb the extra tonnes of cassava, and farmers found themselves forced to sell their crops off cheaply — in some cases, they were unable to sell them at all. Exports of cassava chips to Europe for livestock fodder, have also been falling since 2002 as European farmers have turned to less costly cereal-based feed. In 2004, cassava production suddenly fell by half, with the result that the ethanol factory built by a Chinese group was unable to find enough raw material. Farmers say they are now ready to restart production if they can be assured of sales for their crop.

But markets exist in the increasingly populated urban areas, as do technologies offering consumers cassava-based products that are easy to use. Good examples can be found in the Caribbean, the Pacific and South America, above all in Brazil, which has long been the world’s leading cassava producer. Here, cassava is prepared in a host of different ways, often on an industrial scale, and the products — chips, cakes, frozen dishes — are sold in shops. In Brazil, one chain of stores sells cassava cheese bread. Cassava flour is used as a partial substitute for wheat flour to make traditional bread. In 2002, the Brazilian Congress even passed a law making it mandatory for bread to contain at least 20% cassava flour and 40% in the case of pizza. The idea was to reduce costly wheat imports and develop the commercial potential of local crops. Africa still lags way behind in this respect, though Nigerian bakers are now required to use 10% of cassava flour in their bread (see Spore 117).

A number of techniques developed in Latin America could be used in Africa. Colombian researchers have managed to extend the shelf-life of fresh cassava roots to 3 or 4 weeks by dipping them in wax or paraffin.

Livestock fodder also offers interesting potential. In Africa, less than 2% of cassava is used to feed animals, compared with 30% in Latin America. In Cameroon, researchers estimate that poultry farmers could cut production costs by 40% if they used cassava as part of their chickens’ diet. On a global scale, animal feed represents the main outlet for cassava. Thailand exports an annual 4 to 5 mt of it, mostly to the European Union.

Finally, there are the many industrial uses to which this tuber lends itself. Starch, the main product to be made from cassava, is used in the food and textile industries as well as in the pharmaceutical and rubber sectors. In Africa, few companies make starch, and production does not even supply domestic needs. With the rise in oil prices, the manufacture of cassava-based ethanol, already widely used in Brazil to replace additives in petrol or as a biofuel, could constitute another interesting outlet.

source:http://www.jonesbahamas.com/?c=47&a=7415