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Acknowledgment -- Table of content -- List of tables -- List of figures -- 1. General introduction -- 2. Analytical methods -- 3. Processing Properties of New Indonesian Potato Cultivars -- 4. Effect of Potassium Fertilization on Potato Tubers Quality -- 5. Effect of Ultrasonication on Potato Chips Color -- 6. Conclusion -- 7. Summary -- Curiculum Vitae

The CGIAR Research Program (CRP) on Roots, Tubers and Bananas (RTB) includes vegetatively propagated staple crops linked by common breeding, seed, and postharvest issues, and by the frequency with which women are involved in their production and use. RTB crops are the backbone of food security across the humid tropics in sub-Saharan Africa (SSA) and in more localized areas of Asia and Latin America. Around 300 million poor people in developing countries currently depend on RTB value chains for food security, nutrition and income. Climate change poses challenges which could undo progress in poverty reduction and markedly increase food insecurity. This article examines planning and research for climate resilience across RTB crops, with a particular focus on the contrasting potato and sweet potato cases in SSA. A six-step framework for climatesmart breeding is proposed: (1) downscaling climate change models and crop modeling; (2) identifying and understanding key climate change responsive traits; (3) breeding and varietal selection; (4) phenotyping and genomic research to accelerate gains; (5) developing management options for climate-smart varieties; and (6) deployment (seed systems). In summary, climate-smart breeding means we need to do what we already do but faster, better, and smarter.

Acknowledgement -- Table of Contents -- List of Tables -- List of Figures -- 1. Introduction -- 2. Characterization of the geographical origin of potatoes in Germany by the stable isotope ratio of the tubers -- 3. Characterization of the geographical origin of potatoes in Germany by the mineral composition of the tubers -- 4. Evaluation of the after-cooking darkening of table potatoes and the contribution of selected tuber constituents -- 5. General conclusion -- 6. Summary -- 7. Appendices -- CURRICULUM VITAE

Pachyrhizus erosus is a legume plant that produces tubers rich in nutrients (protein, iron, zinc, etc.) that are used in various kinds of food processing. The objective of this study was to analyse producers' and processors' perception regarding processing P. erosus tubers into gari in on-farm conditions and its financial profitability. Kendall's concordance test was used to classify perceptions, and cost analysis was used to analyse the profitability of the product. The results showed that the mixed gari with 50% P. erosus was highly appreciated because of its greater fermentation ability than cassava gari. The price at which processors broke even was FCFA 340 (~ $ 0.57) per kilogram and the sensitivity analysis revealed that when the yield of P. erosus-based gari increased by 30%, processors made a profit of 25% of the investment cost. So, processing of P. erosus is beneficial for the processors and consumers appreciate it more than cassava gari. The Benin Government needs to promote this crop in order to feed its population.© 2015 International Formulae Group. All rights reserved.Keywords: Roots and tubers, technical performance, malnutrition, Benin, population, food quality

The results of experimental studies are presented, determining the internal defects of potato tubers using nuclear magnetic resonance (NMR) method, which provide access to information about the state and distribution of water at the cellular and tissue levels. In order to carry out internal defect detection studies, three groups of potato tubers were prepared, comprising conditioned and unconditioned samples. The total sampling of potato tubers amounted to 38 samples. To create hidden defects in the form of darkening of tuber pulp, the method of controlled impact on a hard surface was used. Methodology for conducting experimental studies and time parameters of NMR are described. The studied potato tubers were placed in a strong magnetic field with intensity of 1.5 Tesla. Analysis of T2 images was chosen as the main method for analyzing the obtained results, since this method allows to trace one of the most important indicators of detecting internal damage of potato tubers – lack of water in the damaged areas of the pulp. The damaged areas in the images of tubers have a dark color, while the healthy tissue is light. A comparative analysis of images obtained using NMR and full-scale images of tubers' section was carried out, allowing to determine with high accuracy the coincidence of location of defects detected by non-invasive method with their actual location in the tuber. The study showed the value of NMR for a detailed non-invasive method for determining hidden defects in potato tubers on automatic grading machines.

This study was driven by the stringent environmental legislation concerning the consumption and utilization of eco-friendly materials. Within this context, this paper aimed to examine the characteristics of starch and fibres from the Dioscorea hispida tuber plant to explore their potential as renewable materials. The extraction of the Dioscorea hispida starch and Dioscorea hispida fibres was carried out and the chemical composition, physical, thermal, morphological properties, and crystallinity were studied. The chemical composition investigations revealed that the Dioscorea hispida starch (DHS) has a low moisture t (9.45%) and starch content (37.62%) compared to cassava, corn, sugar palm, and arrowroot starches. Meanwhile, the Dioscorea hispida fibres (DHF) are significantly low in hemicellulose (4.36%), cellulose (5.63%), and lignin (2.79%) compared to cassava, corn hull and sugar palm. In this investigation the chemical, physical, morphological and thermal properties of the Dioscorea hispida fibre and Dioscorea hispida starch were examined by chemical composition investigation, scanning electron microscopy (SEM), particle size distribution, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and Fourier transform infrared (FTIR), respectively. It was found that Dioscorea hispida waste is promising alternative biomass and sustainable material with excellent potential as a renewable filler material for food packaging applications.