This study has been part of a co-operation between the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH, the Federal Ministry for Economic Co-operation (BMZ) and the Ministry of Agriculture, Ghana. The research has been carried out at the Division of Plant Protection - Phytomedicin, Institute of Horticultural Sciences, Faculty of Agriculture and Horticulture, Humboldt University of Berlin and the Institute for Stored Product Protection of the Federal Biological Research Centre for Agriculture and Forestry (BBA) in Berlin. I am thankful to all these institutions for their financial support and kind assistance.
I express my gratitude to GTZ GmbH and mainly Department 423 - Plant-and Post-Harvest Protection - for their assistance and encouragement, especially Dr. Ulrich Röttger, Dr. Adolf Laborius, Dr. Rolf Link, Rüdiger Harnisch and Albert Bell.
A special thank you to Prof. Dir. Dr. Christoph Reichmuth of BBA for his continuous support and constructive suggestions throughout my research and I want to extend that thanks to the BBA team, including Cornel Adler, Werner Rassmann, Gerhard Schmidt and colleagues such as Ana-C. Sà-Fischer, Abdul Gabar, Matthias Schöller, Sebastian Okello, Sabine Prozell and Alexander Wudtke for their professional assistance. I thank Dr. George Mbati, who contributed valuable comments to the thesis. I thank the BBA library staff, especially Alain Leprétre. Also, special thanks to Dr. Moll of BBA Kleinmachnow Berlin, who assisted me in analysing the immense amount of experimental data.
Prof. Franz-Adalbert Schulz, my former supervisor who died tragically in 1995, I thank for his academic support, and the Institute for Horticultural Sciences and the team for their excellent assistance.
A big thanks to Prof. Bochow, who took over the supervision from Prof. Schulz and supported and encouraged me throughout the final stages of my thesis.
I also thank the National Resource Institute (NRI) in Chatham and in Ghana, namely Marc Wright, Robin Boxall, Julia Compton and Stephanie Gallat for their co-operation.
A special thanks is reserved for the GTZ post-harvest project in Tamala, Ghana, and namely Christian and Petra Henckes for their help, academically and privately. I wish to extend that thanks to the project team and the Ministry of Food and Agriculture (MOFA) of the Northern Region - Mr. Fuseini, Mrs. Aku, Mr. Tikumah - as well as the national co-ordinator for post-harvest issues, Mr. Kwaku Nicol. I am also much obliged to the Regional Director, Mr. Salifu, and the Deputy Regional Minister of Food and Agriculture, Mr. Iddi, for their co-operation and support during my stay at the Ministry of Agriculture, Tamale.
As usual such a research programme would not have been possible without the co-operation of the farmers in the Northern Region of Ghana. They supported me in every respect, and it was very pleasant to work with them and also to learn a great deal about their life.
For the drawings of the vacuum equipment, the visual damage scales and the various storage and drying structures I thank Goddie from Tamale, Ghana.
Special debt is owed to Mrs. Jennifer Mulligan for her careful editing and proofreading.
I'm especially grateful to Harriett Balzer for her excellent contribution to the lay-out of the thesis, compiling and typesetting.
Life was easier in Berlin and Tamale because of support received from a number of friends and family. A big thanks to Isolde Lutz, Ana-Christina and Eric Sà-Fischer, Stephanie Gallat and Jon-K, Wolfram Stolz, Birgit Seeber, Valerie Remidios, Anna Masacorale, Harriett Balzer, Sebastian Okello, Gudrun Peckenschneider, Manfred Matz, Helga Becker and, of course, my family.
Acronyms and definitions
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BBA |
= Biologische Bundesanstalt (Federal Biological Research Centre for Agriculture and Forestry), Königin-Luise Str. 19,14195 Berlin, Germany |
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Bentert |
= (company) Hochbaumstr. 22,14167 Berlin, Germany |
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Cassava Chips |
= Anglophone expression for dried pieces of the cassava root |
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Cedis |
= Ghanaian currency (1 DM = 674 Cedis, January 1995) |
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Cossettes |
= Francophone expression for dried pieces of the cassava root |
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ECO SYS |
= (company) Chemische Analysen GmbH, Nicolaus Singeisenweg 4, 79560 Schopflheim, Germany |
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FAO |
= Food and Agriculture Organisation of the United Nations |
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GDP |
= Gross Domestic Product |
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GM |
= Gravimetric method |
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GNP |
= Gross National Product |
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GTZ |
= Gesellschaft für technische Zusammenarbeit GmbH |
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HCN |
= Hydrogen cyanide |
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Kokonte |
= Ghanaian name for dried chips but also used for flour products made out of chips. |
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MOFA |
= Ministry of Food and Agriculture, Ghana |
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MM |
= Manometric method |
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Post-harvest |
= a set of operations and functions including harvest, processing, transport, system |
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system |
storage and consumption of agricultural commodities that are fulfilled by different agents to achieve effective and efficient food supply, and the interaction between them |
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PPMED |
= Policy Planning, Monitoring and Evaluation Department, Ghana |
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r.h. |
= Relative humidity |
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sd |
= Standard deviation |
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SORAD |
= Cassava variety from Togo |
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T.Z. |
= tuo-zaafi, local dish in the Northern Region of Ghana |
|
VDSM |
= Visual damage scales method |
|
VGM |
= Volumetric/gravimetric method |
