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The Water for Food Paradox 全文
2013
Chartres, C. | Sood, A.
This paper considers whether there will be sufficient water available to grow enough food for a predicted global population of 9 billion in 2050, based on three population and GDP growth modelling scenarios. Under the a low population growth with high GDP growth scenario, global consumptive water demand is forecast to increase significantly to over 6,000 km3, which is approximately 3,000 km3 greater that consumptive use in the year 2000. Also of concern is that rising global temperatures are going to increase potential evaporation, and t us irrigation water demand, by up to 17%. Sustainable intensification of agriculture can provide solutions to this predicament. However, productivity growth i not fast enough and we face considerable risks in the next 20 to 30 years. Concerted action to combat food insecurity and water scarcity is required based on agricultural research and development, policy reform and greater water productivity, if the world is to feed its growing population.
显示更多 [+] 显示较少 [-]Measurement of free water in foods by secondary derivative thermogravimetry | Medición del agua libre en alimentos mediante termogravimetría de segunda derivada 全文
2018
Wang, Yubin | Zheng, Qingyun | Li, Wu | Ma, Yue | Zhao, Xiaoyan | Zhang, Chao
The thermogravimetry (TGA) and derivative thermogravimetry (DTG) methods have been used to measure the free water in low-moisture foods. In this study, the 2nd derivative thermogravimetry (2nd DTG) method distinguished the free and bound water based on the speed of moisture evaporation, which could be used for both low-moisture and high-moisture foods. First, the key factors related to moisture evaporation were optimized. Isothermal temperature of 30 ~ 50°C, dynamic temperature of 0.033 ~ 0.133°C/min, and flow rate of nitrogen of 20 ~ 40 mL/min were the optimal parameters for the 2nd DTG method. Under these conditions, the repeatability and reproducibility of the 2nd DTG method were enhanced, its applicability was expanded to high-moisture foods, and the accuracy was ± 4.0% of the nuclear magnetic resonance results. Hence, the 2nd DTG method is better suited for the measurement of free water in foods.
显示更多 [+] 显示较少 [-]SYNTHESIS OF FOOD GRADE SALT FROM BRINE WATER OF TIRTA SANITA BOGOR 全文
2021
Ermiziar Tarmizi | Kudrat Sunandar | Agam Duma Kalista Wibowo
ABSTRACT Tirta Sanita Bogor brine water contains high concentrations of sodium (Na). It also contains calcium (Ca) and magnesium (Mg). The purpose of this research is to make the food grade salt with relatively low Ca and Mg content. The process was carried out in two methods, the first method was chemical precipitation which was divided into two stages, the removal of the Mg element using a limestone compound (CaCO3) which has been calcined at 900 ̊C for 6 hours, and the removal of Ca element using Li2CO3 compound. The second method was traditional evaporation which was conducted using prism greenhouse technology. The brine filtrate was reacted with Na2CO3 and the results were analyzed using the ICP-OES. The results showed that the NaCl content was 80% by the chemical precipitation and traditional evaporation methods. Keywords: Brine water, Precipitation, Evaporation, Food grade salt
显示更多 [+] 显示较少 [-]Irrigation schedules for selected food crops using water balance book-keeping method
2014
Ezemonye, M.N., University of Benin, Benin City (Nigeria). Dept. of Geography and Regional Planning | Emeribe, C.N., University of Benin, Benin City (Nigeria). Environmental Pollution Remediation Unit
In the tropics, the water potential of a region cannot be adequately assessed from precipitation alone due to the seasonal character of rainfall and even more so owing to the changing climate scenario. It is therefore necessary that in any agro-climatological program, there must be a clear understanding of the actual amount of water that evaporates and transpires (AET), and the amount of water that would evaporate and transpire if water were always readily available (PET). This could be done through the method of the water balance. The present work examines the water budget of parts of the Imo river basin and its implications for improved crop production through supplementary irrigation schedules. It was observed, that the study area is already facing moisture-stress. This is because even during rainy months supplementary irrigation is required to compensate for the occasionally moisture deficit due to increased evapotranspiration. The study showed that cultivation of maize, rice and tomatoes can be carried out on an all-year round basis under a scientific irrigation scheme. Thus the study provided farmers with guideline on the period and quantity of water required for supplementary irrigation, a development which will prevents wilting of plants before the application of needed water.
显示更多 [+] 显示较少 [-]Determination of kinetic and thermodynamic parameters of food hydrocolloids/water interactions by means of thermal analysis and viscometry 全文
2018
Valenta, Tomáš | Lapčíková, Barbora | Lapčík, Lubomír
The aim of this study was to determine thermal properties of pseudoplastic polysaccharides (guar gum, κ-carrageenan and xanthan gum) which find many applications as food hydrocolloids in food industry. There was an obvious relationship between thermal dependency of heats of fusion of hydrocolloids in powder form and activation parameters of hydrodynamic flow in solutions, respectively. Results of thermal analysis confirmed, that powder samples of hydrocolloids as typical foodstuffs of low moisture content less than 15 w% after room conditioning, exhibited varying ability to bind water as depending on their molecular structure. The peak temperature of the endothermic polysaccharide order-disorder phase transition process was found in the temperature range of 50–85 °C. It was influenced simultaneously by the applied heating rate and the samples moisture content. Studied samples moisture content was ranging between 9–40 w.% as was obtained after different conditioning. Observed reaction enthalpy (ΔH) associated with phase transition and water evaporation (proved by appropriate weight loss of the samples Δmw) was ranging from 140 to 670 J/g. Activation energy (Eₐ) of this process in powder samples was calculated from the kinetic parameters using three kinetic models developed by Friedman, Kissinger and model-free kinetics. The latter kinetic models were compared with the Arrhenius model, which was used to determine Eₐ of polysaccharide solutions on reflecting sensitivity of their molecular structure to the temperature and the solvent. According to the Arrhenius model, there were obtained the highest values of Eₐ for κ-carrageenan solutions, indicating the highest resistance of their molecular structure to temperature. This fact can be related to the observed the lowest value of the reaction enthalpy in the case of powder samples, suggesting that energy obtained during the order-disorder transition to change the carrageenan powder structure is limited. On the other hand, xanthan gum was the least temperature dependent sample; activation energy of xanthan solutions was only in the range of 2–6 kJ/mol. Concurrently, ΔH of xanthan powder was determined as the largest of all samples under study. In general, there was found an indirect relationship between activation energy of the solutions determined by viscometry and reaction enthalpy of the powders determined by thermal analysis. Results of the Arrhenius model also indicate that the energy necessary to promote viscous flow of solutions is higher for hydrocolloids in distilled water rather than in 0.07 M KCl aqueous solutions, suggesting the suppression of the polyelectrolyte effect. In both cases, Eₐ was substantially reduced by application of higher shear rate.
显示更多 [+] 显示较少 [-]Life Cycle Assessment of Animal Feeds Prepared from Liquid Food Residues: A Case Study of Rice-Washing Water 全文
2012
Ogino, Akifumi | Ishida, Mitsuyoshi | Ohmori, Hideyuki | Tanaka, Yasuo | Yamashita, Takahiro | Yokoyama, Hiroshi | Tatsugawa, Kenji | Ijiri, Satoru | Kawashima, Tomoyuki
Life cycle assessment (LCA) was used to compare the greenhouse gas (GHG) emissions and energy consumption of three methods used to produce animal feed from concentrated rice-washing water (CRW) and disposing of the rice-washing water through wastewater treatment. Four scenarios were compared using LCA: (i) producing concentrated liquid feed by centrifugation (CC) of CRW with wastewater treatment and discharge of the supernatant, (ii) producing concentrated liquid feed by heating evaporation (HC) of CRW, (iii) producing dehydrated feed by dehydration (DH) of CRW, and (iv) wastewater treatment and discharge of nonconcentrated rice-washing water (WT). The functional unit (FU) was defined as 1 metric ton of rice washed for cooking or processing. Our results suggested that the energy consumptions of CC, HC, DH, and WT were 108, 322, 739, and 242 MJ per FU, respectively, and the amounts of GHG emissions from CC, HC, DH, and WT were 6.4, 15.8, 45.5, and 22.5 kg of CO₂ equivalents per FU, respectively. When the produced feed prepared from CRW was assumed to be transported 200 km to farms, CC and HC still emitted smaller GHGs than the other scenarios, and CC consumed the smallest amount of energy among the scenarios. The present study indicates that liquid feed production from CRW by centrifugation has a remarkably reduced environmental impact compared with the wastewater treatment and discharge of rice-washing water.
显示更多 [+] 显示较少 [-]Influence of the relative humidity on the water drying rate and on the bacterial growth or inactivation in a food processing plant 全文
2017
Lecoq, Logan | Guillier, Laurent | Fritsch, Lena | Hoang, Hong-Minh | Flick, Denis | Laguerre, Onrawee | Ingénierie, Procédés, Aliments (GENIAL) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Université Paris Saclay (COmUE) | Génie des procédés frigorifiques (UR GPAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Food Safety Laboratory | French National Research Agency [EcoSec Project, ANR-12-ALID-0005-04] | Laboratory of Food & Biosystems Engineering (FABE Lab).
International audience | A heat and mass transfer model was developed to predict, during the drying of a food processing plant, the evolution of the water mass, wet surface, air temperature and relative humidity. The model was previously validated by comparing the predictions with the experimental results obtained in a food processing plant. Then, this model was coupled with a microbiological model to predict the fate of Listeria monocytogenes (growth or inactivation) at different locations in the plant (floor, wall and equipment). Simulations were carried out for blown air at 50%, 68% and 85% relative humidity in order to study the influence of air dehumidification in the plant on the drying rate and on the evolution of the microbial load. It was found that bacteria are more likely to develop on equipment when the drying time is longer. A technical solution involving heating of the equipment was proposed and the impact on the wet surface and the evolution of the microbial load was presented.
显示更多 [+] 显示较少 [-]ANALISIS NERACA AIR UNTUK PENGEMBANGAN TANAMAN PANGAN PADA KONDISI IKLIM YANG BERBEDA Water Balance Analysis for the Development of Food Crops in a Different Climate Conditions 全文
2012
Mardawilis | Sudira, Putu | Sunarminto, Bambang Hendro | Shiddiq, Dja’far
In order to develop food crops in upland in the tropics area, the potential water resources, such as the availability of soil moisture and surface water can be used as a source of water supply especially during the deficit. Therefore, to develop a sustainable food crop, the water balance analysis is absolutely necessary. The data used were series of climate data (temperature, precipitation, evaporation) for 37-year period (1971-2007) at Japura station, Rengat, Riau, heat index data and soil data (soil moisture at field capacity and permanent wilting point) and the effective rooting depth. Exceeded rainfall probabilities and water balance were analyzed using statistical methods. The results showed that soil moisture conditions were always above the limit of water availability for crops although the water balance was deficit for normal, wet and dry conditions. This shows that food crops can be planted all for the whole year in the research area. ABSTRAK Dalam rangka pengembangan tanaman pangan di lahan tadah hujan/kering di daerah tropik basah, potensi sumberdaya air, baik berupa ketersediaan lengas tanah maupun air permukaan dapat dijadikan sebagai sumber pasokan air terutama pada saat defisit. Oleh sebab itu untuk pengembangan tanaman pangan yang berkelanjutan, maka analisis neraca air mutlak diperlukan. Data yang digunakan berupa data seri iklim (temperatur udara, curah hujan, evaporasi) periode 37 tahun (19712007) stasiun Japura, Rengat, Riau, data indeks panas serta data tanah (lengas tanah pada saat kapasitas lapang dan titik layu permanen) serta kedalaman perakaran efektif. Peluang curah hujan terlampaui dan neraca air dianalisis meng gunakan metode statistik. Hasil penelitian menunjukkan bahwa keadaan lengas tanah selalu pada batas air tersedia bagi tanaman meskipun neraca air mengalami defisit baik pada kondisi normal, kering maupun basah. Hal ini menunjukkan bahwa di wilayah penelitian dapat dilakukan penanaman tanaman pangan sepanjang tahun.
显示更多 [+] 显示较少 [-]Recommendations concerning agricultural development with improved water control in the Mekong delta. Main report. - Working paper 1: Impact of rainfall and food on paddy production.- Working paper 2: Climate: an analysis of evaporation and rainfall for agricultural purposes.- ... 4: Hydrology.- ... 5A: Agriculture, land resources.- ... 5B: Agriculture, social and economic aspects.- ... 6: Irrigation and Drainage.- Appendix A: Evaluation of possible development,.- ... B: Identification of further surveys and investigations
1974
Committee for Coordination of Investigations of the Lower Mekong Basin, Bangkok (Thailand) eng | Ministerie van Buitenlands Zaken, The Hague (Netherlands). Directie Internationale Technische Hulp oth