Climate Change is real and its implications are going to be borne by the poorest of the poor. If climatic change is accompanied by an increase in climate variability, many agricultural Producers will experience define hardships and increased risk. The Sat regions, which have economies largely based on weather-sensitive agricultural productions systems, are particularly vulnerable to climate change...............................

PR | IFPRI5 | EPTD | xv, 265 p. : col. ill. ; 24 cm.

The impact of water on food thermodynamics and physics, and therefore on its quality, is more important than any other food chemical component. When fundamentals of chemical kinetics apply, the rates of the reactions that are responsible of food quality decay can be described as a function of food composition and of other external elements interacting with foods. Among them, water activity and water content have been widely used to determine the role of water in the kinetic reactions of deterioration. Recently, researchers have found limitations in using the water activity parameter. According to them, the role of water in foods can be better described by evaluating the role in the stability of the quality attributes of the non-equilibrium states of amorphous food products. Following this approach, the dynamics of the changes are described in kinetics terms and can be efficiently better predicted by the glass transition temperature more than by the water activity. The glass transition, which is a second order transition in amorphous materials from the glassy to the rubbery state, is primarily dependent on water which is a plasticizer and is responsible for the physical state of multiphase systems (as foods are) together with the temperature. The subject of the role of water in the decay of food quality will be presented in this paper according to the principles of food material science.

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In recent years, a greater level of integration of the world economy and an opening of national markets to trade has impacted virtually all areas of society. The process of globalization has the potential to generate long-term benefits for developing countries, including enhanced technology and knowledge transfers and new fina- ing options supporting agricultural and economic development. However, risks of political and economic instability, increased inequality, and losses in agricultural income and production for countries that subsidize their agricultural and other e- nomic sectors threaten to offset potential benefits. Globalization can also have a profound impact on the water sector – in terms of allocation and use of water – and thus on food security as well. Other global change processes, particularly climate change, are also likely to have far-reaching impacts on water and food security, and societies around the world. To discuss these issues in-depth, the International Food Policy Research Institute, the Third World Centre for Water Management, Mexico, and the Tropical Agricultural Research and Higher Education Center (CATIE), Costa Rica, held a three-day International Conference on “Globalization and Trade: Implications for Water and Food Security,” at CATIE’s Turrialba, Costa Rica, headquarters under the auspices of the CGIAR Challenge Program on Water and Food in 2005. The workshop set out to identify the major risks and emerging issues facing developing countries related to global economic and environmental change impacts on water and food security.

Este trabajo presenta la viabilidad de los sistemas de refrigeración solar por absorción usando soluciones de monometilamina - agua (MMA-A) para aplicaciones en conservación de alimentos en las regiones rurales de Colombia, sin acceso a la red de energía eléctrica. Para suplirlos requerimientos de energía térmica se propone un sistema de calentamiento de agua con energía solar usando colectores de placa y un sistema de respaldo convencional. En este trabajo se determinó el coeficiente de operación (COP) del sistema de refrigeración solar por absorción de una sola etapa en función de la temperatura en los diferentes componentes del ciclo. Los resultados indican que el sistema podría mejorarse mediante un mejor diseño en el intercambiador de calor de solución, el evaporador y el rectificador. Los resultados teóricos demuestran que el uso de la solución de MMA-A puede ser usada en sistemas de refrigeración por absorción operados con energía térmica de baja calidad, tales como la energía solar.<br>Este trabalho apresenta a viabilidade e aplicabilidade dos sistemas de refrigeração solar por absorção usando como parelha a monometilamina - agua (MMA-W) para fins de conservação de alimentos ñas regiões rurais da Colômbia, onde não há energía disponível. Propõese um sistema de calefação solar mediante coletores solares de placa plana com um sistema convencional de aquecimento auxiliar para suprir as necessidades energéticas do refrigerador por absorção. Determinou-se o coeficiente de desempenho (COP) do sistema de refrigeração solar por absorção só de uma etapa em funçã da temperatura nos diferentes componentes do ciclo. Os resultados indicam que o sistema poderia se melhorar mediante um desenho melhorno intercambiador de calor de solução, o evaporador e o retificador os resultados teóricos demonstram que o uso da solução de MMA-W pode ser usada em sistemas de refrigeração como parelha absortiva operado pela energía térmica de baixa qualidade, como a energía solar.<br>This work reports the applicability of monomethylamine-water solutions in a solar absorption refrigerator for food conservation purposes in the rural regions of Colombia , where no electricity is available. A solar heating system using fíat píate solar collectors with a conventional auxiliary heating system is proposed. We have determined the COP of the solar single-stage absorption refrigerator as a function of the temperature in the different components of the cycle. The results indícate the system might be improved by better design on the solution heat exchanger, the evaporator and the rectifier. The theoretical results prove that the use of MMA-W solution can be driven bylow-grade thermal energy such as solar energy.

Arsenic is a toxic metalloid of global concern. It usually originates geogenically but can be intensified by human activities such as applications of pesticides and wood preservatives, mining and smelting operations, and coal combustion. Arsenic-contaminated food is a widespread problem worldwide. Data derived from population-based studies, clinical case series, and case reports relating to ingestion of inorganic arsenic in drinking water, medications, or contaminated food or beverages show the capacity of arsenate and arsenite to adversely affect multiple organ systems. Chronic arsenic poisoning can cause serious health effects including cancers, melanosis (hyperpigmentation or dark spots, and hypopigmentation or white spots), hyperkeratosis (hardened skin), restrictive lung disease, peripheral vascular disease (blackfoot disease), gangrene, diabetes mellitus, hypertension, and ischemic heart disease.