Innovations for Agricultural Value Chains in Africa: Applying Science and Technology to Enhance Cassava, Cassava Value Chain

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1 Innovations for Agricultural Value Chains in Africa: Applying Science and Technology to Enhance Cassava, Dairy, and Maize Value Chains Cassava Value Chain June 3, 2009

2 What is a Value Chain? A value chain is a series of sequential activities, where at each step in the process the product passing through this chain of activities gains value. Generally, the chain of activities gives the products more added value than the sum of the added values of all activities. 1

3 What is Cassava? Overview and Importance as a Crop An edible, tuberous root grown underground Drought and disease resistant; primary food security crop Reliable and inexpensive source of carbohydrates in SSA Used as substitute for wheat as glue extender for plywood, animal feed, and food products for human consumption. Highly commercialized in parts of West Africa, but less so in East Africa Potential to significantly increase smallholder farmers incomes; fresh cassava has a low value/bulk ratio and is perishable, thus marketability is strictly local If efficiently processed, cassava likely to gain in domestic demand and as a potential export 2

4 Consumption Habits Nine categories of traditional cassava uses 1. Cooked fresh roots (includes pounded fresh cassava, locally known as fufu in Ghana) 2. Cassava flours: fermented and unfermented 3. Granulated roasted cassava (gari) 4. Granulated cooked cassava (attieke, kwosai) 5. Fermented pastes (agbelima, fufu in Nigeria) 6. Sedimented starches 7. Drinks (with cassava components) 8. Leaves (cooked as vegetables) 9. Medicines 3

5 Primary Constraints Two major constraints to development of cassava post-harvest systems Perishability of fresh roots within 48 hours Processing is important because of low marketability of fresh cassava Presence of cyanogenic compounds If inadequately processed then the cyanogenic glucosides will pose a serious health risk to consumers 4

6 Other Issues that Threaten Transitions of Processed Cassava Lack of appropriate and affordable technologies Competitiveness of cassava (related to costs of production) Weak private sector (including intermediary processors and bulking agents that link small-scale producers and processors with end-use industries) Trade policies Consumer preferences Price volatility Market dynamics Gender inequities 5

7 Value Chain Elements Associated Steps Harvest Storage and aggregation Processing (some, and at times all, of the associated steps) Root preparation (peeling and slicing) Size reduction (grating) Fermentation Drying and/or dewatering Sieving Overarching issues to be aware Quality indicators Cyanogenic compounds 6

8 Harvest Constraints and Technology Considerations Labor intensive Non-mechanized Technology Consideration: Mechanization of harvest through tools and equipment 7

9 Raw Cassava Storage Constraints and Technology Considerations Perishability within 2 days of harvest High land consumption and inefficiency when cassava remains unearthed v advantage of year round availability Some innovations in storage with damp, dark crates and bags/sacks for low-cost storage lasting a few weeks Technology Consideration: Storage and packaging technologies will contribute to increasing cassava root availability and maintaining quality 8

10 Root Preparation (peeling/slicing) Constraints and Technology Considerations Labor intensive Non-mechanized Traditionally done by women Critical stage in food safety since process removes outer periderm with highest concentration of cyanogenic compounds Aim to maintain the highest volume of usable cassava (abrasion technologies) 9

11 Root Preparation (continued) Constraints and Technology Considerations Technology Consideration: Mechanization of peel removal Technology Consideration: Mechanization of slicing where needed for specific products Examples of rotary abrasive cassava peelers (right) 10

12 Size Reduction (grating) Constraints and Technology Considerations Often mechanized in West Africa, but can be very labor intensive if non-mechanized Purpose is to increase surface area for drying Technology Consideration: Improve efficiency of existing grating technologies Graters, including a portable example (left) 11

13 Drying and Dewatering Constraints and Technology Considerations Cassava is 70% water by volume; drying and dewatering are essential step for flours Reliance on sun dryers, which take more time but are cheaper Time and seasonality and impact on price volatility Compared to the sun, bin dryers save time, ensure a consistently high quality product, but pose a significant increase in cost Flash dryers are used in Nigeria, but need further development and price reduction Dewatering through pressing results in polluting waste products with no proper disposal methods 12

14 Drying and Dewatering (cont.) Constraints and Technology Considerations Technology Consideration: Improved mechanized (flash and bin) dryers Technology Consideration: New energy sources for flash, bin, or other dryers Technology Consideration: Improvements to sun drying Technology Consideration: New approaches to drying (or alternatives such as slurry) Technology Consideration: Waste reduction and water treatment/recycling for dewatering Examples of dryers: sun (1), batch (2), flash (3) (right)

15 Fermentation Constraints and Technology Considerations Three types of fermentation employed Root fermentation Underwater/soaking fermentation Mold fermentation Present research has focused on understanding the microbiology of these fermentation techniques and the mechanisms by which cyanogenic compounds are reduced Technology Consideration: Improvements to fermented products Technology Consideration: Identification of pure cultures, optimal temperatures, ph, and enzymes 14

16 Cyanogens Additional Factor and Technology Considerations If ingested in significant quantity, cyanogenic compounds can lead to acute intoxication, causing nausea, dizziness, vomiting, and sometimes death Wetting method prior to consumption has proven helpful Cyanogens more prevalent in some varieties than others Measurement of cyanogens available only for laboratories Technology Consideration: Low-cost cyanogens detection tools Technology Consideration: Ensuring that innovations in processing deliver a safe product Technology Consideration: Rapid processing technique for bitter varieties that deliver a safe product 15

17 Quality Additional Factor and Technology Considerations Quality can be variable in traditional products Variations in drying, processing, storage can have major impacts Demand for higher quality, consistent products Technology Consideration: Techniques to ensure quality in value chain 16