RMRDC: Building Nigeria’s GDP via  confectioner’s glucose

The Raw Materials Research and Development Council (RMRDC) is improving on the production of bioethanol, glucose syrup and animal feeds from sweet sorghum to save Nigeria the much needed foreign exchange and boost the nation’s Gross Domestic Products (GDP). BINTA SHAMA reports.

Bioethanol

Bioethanol according to study, is said to refer to pure ethanol which is produced from a variety of feed stocks including grains most especially maize, agricultural wastes, and other biomass resources. The production of bioethanol is said to have increased in the 19th century due to economic improvements in the distillation process. More recently, sweet sorghum has become a very important raw material for bioethanol production in view of its special attributes, most especially, the syrup present in its stalk. Bioethanol is used in industrial circles for production of perfumes, cosmetics and glucose syrup which is employed in the production of soft drinks, fruit juices and confectioneries, etc. Bioethanol is also extensively used as fuel in various combustion engines, especially in automobiles. It is the only direct substitute for fossil fuels that is available on a significant scale. About 93.6 billion litres of bioethanol were produced in 2016, compared to about 27 billion gallons produced globally in 2021, most of which is obtained  from corn starch and sugarcane. The united States is the world’s leading producer with about 15 billion gallons. While Nigeria for instance, produces 134 million liters of ethanol per annum from five major commercial-scale ethanol distilleries.

Interest in biofuels

The development of bioethanol is important as the global fossil fuel resource is thinning in availability regardless of the use of new technologies or the discovery of new oil deposits. The instability in the price of oil and the negative impact on the environment, human and biochemical cycles are propelling systematic shift towards biogeochemical cycles. As a result, the interest in biofuels is growing rapidly due to concerns about climate change from greenhouse gas emission and desire to promote domestic rural economy.

Raw materials for bioethanol

Bioethanol is produced from biomass mostly through fermentation process using glucose derived from sugars (sugar cane, sugar beet and molasses), starch (corn, wheat, grains) or cellulose (forest products) as raw materials. In this form, it is renewable. Thus, first generation raw materials used at commercial scale are corn (maize), wheat, potato, cassava, sugar cane and beet. Nevertheless, the fact that optimal bioethanol feed stocks should be controlled by the chemical composition of the biomass, cultivation practices, availability of land and land use practices, energy balance, emission of greenhouse gases, acidifying gases and ozone depletion gases, absorption of minerals to water and soil, pesticides requirement, soil erosion, contribution to biodiversity and landscape value losses, farm-gate price of the biomass, cost of transportation and storage of the biomass, the direct economic value of the feed stocks taking into account the co-products, creation or maintenance of employment and the water requirements and water availability has made bioethanol production from these sources unsustainable. For instance, corn is a major raw material for global ethanol production. In 2016, the world ethanol production was 93.6 billion liters and rose to 96 billion litres in 2017. The global share of corn accounts for more than 80%. However, corn is widely cultivated for its edible seed especially in tropical and warm temperate zones of the world. The present annual production exceeds over 1 billion MT. The USA and China are the major producers. The major challenge in corn production is its high requirement of fertilizers and pesticides. This makes its production cost high and its cultivation expensive for peasant farmers in most developing countries, most especially, where there are no subsidy regimes.

Cassava 

Another major raw material is cassava. It is one of the most important food crops in the humid tropics. It is highly adaptable to conditions of low nutrient availability and it Is able to survive drought conditions. However, with over 200 million MT of world cassava root production, ethanol produced from cassava starch contributes less than 8% of total global ethanol production. The use of cassava for ethanol production faces stiff competition in many African countries where it is used to produce many staple products that yield more income for farmers. Nigeria for example, is the highest producer of cassava with over 40 million MT/annum, yet it contributes less than 0.05% of the global glucose syrup and ethanol production. The implication of this is that if Nigeria must compete as a major player in global ethanol production, newer sources of raw materials must be exploited among the crops that are not fully utilized as staple food crops. Likewise, the use of other first generation biofuels such as sugarcane and sugar beet follow the same pattern as they are important raw materials for food and sugar production globally and the need for conservation of biodiversity make their uses unsustainable.

Importance of sweet Sorghum in bioethanol production

The term “Sorghum” involves a considerable group of annual herbaceous C. species. They are members of the Poaceae family used for centuries in many countries in Africa. Sorghum originates from Ethiopia and spread to parts of Africa, Asia, especially, India and Southeast Asia, Australia and the Americas. There is presently, a growing interest in the species in China and Brazil.

Sorghum has been cultivated in Africa from time immemorial. In Nigeria, sorghum is cultivated extensively in most parts of the northern region for its seed which has various industrial and food applications. However, sweet sorghum is a more recent group of plants, derived from the existing species/subspecies and its varieties or from their hybridization. It is also classified as a member of the Sorghum genus. The cultivated sweet sorghums in general belong to S. bicolor subsp. Bicolor. Sweet sorghum produces stalks that have high concentration of fermented sugars which have become very Important in ethanol production. The sweet sorghum cultivars are of great interest because they produce important amounts of sugar which accumulates in their stems in a very short period of time. This is due to an enhanced glucose production capacity per leaf area surface. In sweet sorghum, biomass synthesis occurs with relatively low energy, chemicals and water inputs, which are typical of C4 plants but that are more significant in this particular case.

RMRDC Initiatives

The primary objective of the Council is to develop sweet sorghum value chain in Nigeria and also to promote the venture as small/medium enterprises in rural areas using the village model system. Emphasis are being placed on the production of glucose syrup and bioethanol for industrial and energy uses. Presently, the primary source of glucose syrup and bioethanol in Nigeria is from starch which is obtained mostly from cassava tuber. Though, the country is the highest producer of cassava in the world, its consumption as a staple food and its high cost make it too expensive and mostly unavailable for the few industries producing starch for syrup production. This makes Nigeria as a nation to depend extensively on the importation of syrup. For instance, between 2011 and 2017, over 300,000 tonnes of syrup valued at $130m was imported. Ekha Agro Farms Limited located at Km 25, Lagos-Ibadan Expressway, is one of the few companies producing glucose syrup from cassava starch. It produces about 26% of national demand, while more than 70% of national requirement is still being imported. Apart from this, Nigeria imported over 71,900MT of ethanol between 2011 and 2017 valued at 200 billion naira for various industrial applications. The need to stem this tide and make the nation self- reliant in the production of bioethanol and syrup made the Council to initiate this project.

Implementation Strategy

The first priority of the Council was to introduce improved sweet sorghum varieties into the relevant ecological zones in Nigeria. This was done in collaboration with the Niger State Government. Eleven sweet sorghum lines from Beijing Sangliang Technology Development Centre (STDC) were obtained and evaluated on a 50 ha farm at Tegina in Niger State in collaboration with institute of Agricultural Research, Zaria. This was to establish the adaptability of the Chinese lines in Nigeria. It was also carried out to see how the plant will react to local pests and diseases. The parameters determined during the trial were the plant height, days of maturity, yield of grains/ hectare, yield of stem cuttings/ha, brix content/plant and stem diameter. The multi-locational and on farm trials on 9 lines were evaluated in 2017 in Samaru, Kaduna State, Tegina, Niger State, Saminaka in Kaduna State, Gabasawa in Kano State and Bakori in Katsina State. 

An abstract from RMRDC projects (concept, implementation strategy and future outlook).