Comparative assessment of amylolytic and cellulolytic enzyme activity of malts prepared from tropical cereals

The activity levels of amylolytic enzymes and β-glucanase in malts prepared from four tropical cereal grains were assessed to establish the relative usefulness of these malts for production of glucose syrups. Rice malt showed the highest activity for the amylolytic enzymes, whilst millet and sorghum malts were richest in β-glucanase activity. Optimum amylolytic enzyme development in rice malts occurred between 9–13 days; and 11 days for optimum β-glucanase development in millet malt. β-Amylase was the predominant enzyme in all the cereal malts except maize, for which the predominant enzyme was α-amylase. Options for optimising the production of enzymes from the three cereals, and their potential for use in the production of glucose syrups are discussed

Influence of variety and growth environment on β-amylase activity of flour from sweet potato (Ipomea batatas)

In order to select a suitable Ghanaian variety of sweet potato as enzyme source for the production of glucose syrups, four varieties of sweet potatoes - Sauti, Santom pona, Faara and Okumkom - cultivated in two different agro-ecological zones of Ghana were evaluated for [beta]-amylase activity. Faara and Okumkom varieties harvested at 5 months maturity from the forest zone showed the highest [beta]-amylase activity and consequently the most suitable potential enzyme source for the hydrolysis of starchy materials in glucose syrup production. Enhancing [beta]-amylase levels in sweet potatoes has potential cost efficiency advantages in glucose syrup production

Adding value to Africa's cassava in a global environment

Based on experiences in the Cassava: Adding Value for Africa (C:AVA) project, this paper examines emerging issues and lessons for adding value to cassava, one of Africa's widely cultivated staples in ways that contribute to the global market environment as well as bring benefits to small holders on the continent. The main issues discussed include: competiveness in the supply of raw material, assisting smallholders to produce value-added products sustainably and competitively, ensuring and maintaining quality of products, selecting appropriate technologies for different circumstances and anticipating negative effects of the market environment on smallholders. One of the main challenges for value addition to a staple crop in Africa is finding 'champions' who are willing to make new investments with knowledge, skill and expertise requirements derived from other nations. The other is increasing the drying capacities for a tropical root crop through appropriate technologies that ensure production of high quality products in required volumes. One focus of the C:AVA project in the near future is to promote transfer of energy efficient Nigerian-made flash drier in collaboration with partners and fabricators from other C:AVA countries (Ghana, Uganda, Malawi and Tanzania). Improved energy efficiency will reduce fuel consumption, reduce operating cost and improve throughput of the dryers. An additional benefit will be reduction in emission of harmful greenhouse gases and their impact on global warming. It is anticipated that the knowledge and skills for further developing the value addition potential for cassava in all five countries will be enhanced. Benchmarking of key variables was used as an approach to understand differences between countries in terms of their abilities to develop high quality cassava flour value chains. It is clear that one strategy does not work in all countries and while positive government support for cassava development is helpful, the real driver is targeting markets according to realisable capacities of the smallholder actors in the value chain

Sustainable inclusion of smallholders in the emerging high quality cassava flour value chains in Africa: challenges for agricultural extension services

Article purchasedBased on the premise that smallholders often get excludedas markets become more commercial, this paper draws lessons from the Cassava: Adding Value for Africa (C:AVA) Project by exploring the main issues and challenges facing extension service partners in five African countries (Nigeria, Ghana, Tanzania, Ugandaand Malawi). These lessons include issues around competiveness in the supply of raw material, assisting smallholders to produce value-added products competitively, working with a range of partners at different stages in the value chain to take pilot studies to scale, ensuring and maintaining quality, selecting appropriate technologies for different circumstances, anticipating negative effects of the market environment on smallholders and ensuring that strategies for ensuring benefits for women and other disadvantaged groups are incorporated into extension service operations. It concluded that one strategy does not work in all countries and, while positive government support for cassava development is helpful, the real challenge is in the need to target markets according to realisable capacities of the smallholder actors in the value chain

Sustainable inclusion of smallholders in the emerging high quality cassava flour value chains in Africa: challenges for agricultural extension services

Based on the premise that smallholders often get excluded as markets become more commercial, this paper draws lessons from the Cassava: Adding Value for Africa (C:AVA) Project by exploring the main issues and challenges facing extension service partners in five African countries (Nigeria, Ghana, Tanzania, Uganda and Malawi). These lessons includes issues around competiveness in the supply of raw material, assisting smallholders to produce value-added products competitively, working with a range of partners at different stages in the value chain to take pilot studies to scale, ensuring and maintaining quality, selecting appropriate technologies for different circumstances, anticipating negative effects of the market environment on smallholders and ensuring that strategies for ensuring benefits for women and other disadvantaged groups are incorporated into extension service operations. It concluded that one strategy does not work in all countries and, while positive government support for cassava development is helpful, the real challenge is in the need to target markets according to realisable capacities of the smallholder actors in the value chain