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Investigation of bound and free water in plant-based food material using NMR T2 relaxometry 全文
2016
Khan, Md Imran H. | Wellard, R Mark | Nagy, Szilvia Anett | Joardder, M.U.H. | Karim, M.A.
Plant-based food materials are porous and hygroscopic in nature; therefore, it contains three water environments, namely, intercellular, intracellular water and cell wall water. The intercellular water is known as capillary water or free water which is less constrained than intracellular water, considered as loosely bound water (LBW), and cell wall water, which is recognised as strongly bound (SBW). During food processing such as drying, frying, heating and cooking, optimisation of heat and mass transfer is crucial. The existing heat and mass transfer models for food processing are developed based on the concept that all of the water inside the food material is bulk water, which can act as free water that can be easily transported. This simplistic assumption has been made due to a lack of sufficient data to enable consideration of the proportion of free and bound water in plant-based food materials. Therefore, the aim of the present study is to investigate the proportion of different types of water such as free, LBW and SBW in 11 different plant-based food materials. The water proportion was investigated using 1H NMR T2 relaxometry. The experimental results uncovers that plant-based food materials contain about 80 to 92% LBW, 6 to 16% free water and only about 1 to 6% SBW. This investigation also confirms that among the five different fruits, kiwi contains the lowest percentage of LBW while Apple contains the highest percentage of LBW. Among the vegetables, eggplant comprises the largest amount of LBW while cucumber contains least amount of SBW. An attempt was made to establish a relationship between physical properties of fruits and vegetables and the proportion of the different types of water. Interestingly, it was found that SBW strongly depends on the proportion of solid in the sample tissue whereas FW depends on the porosity of the material.Food preservation is a major concern in today's world as about one-third of the global food production is lost annually due to lack of proper processing and preservation. Food processing is very energy intensive process and it consumes about 15–20% of energy used in industrial processes. Quality of processed food is also a big concern in the industries. Therefore energy efficiency and food quality are two major concerns in the food processing industry.The current food processing techniques such as drying are unable to ensure best quality and energy efficiency as many microlevel fundamentals of hygroscopic food material are unknown. One of the major unknown is the proportions and characteristics of different types of water inside the food materials and because of this an optimised food processing cannot be designed in order to ensure high quality and energy efficiency. The existing heat and mass transfer models are based on some simplistic assumptions, for instance all of the water inside the food material is considered bulk water; which means that it acts as free water that can be transported easily. This simplistic assumption has long been used due to lack of sufficient data to enable consideration of the proportion of free and bound water. Therefore, the aim of the present study is to determine the proportion of different types of water such as free water, loosely bound water (LBW) and strongly bound water (SBW) and establish relationship between physical properties and water characteristics in hygroscopic food materials.The findings of this study will enhance the understanding of plant-based food tissue that will contribute to a better understanding of potential changes occurring during food processing and will contribute to the development of accurate heat and mass transfer models and prediction of deformation. These findings will ultimately be significant for the equipment design engineers in food processing industry.
显示更多 [+] 显示较少 [-]Application of water-energy-food nexus approach for designating optimal agricultural management pattern at a watershed scale 全文
2020
Sadeghi, Seyed Hamidreza | Sharifi Moghadam, Ehsan | Delavar, Majid | Z̤arghāmī, Mahdī
The increasing demands of the population and the need for development obliged the optimal use and adaptive management of the watershed resources. Accordingly, it is necessary to adopt comprehensive measures to reach sustainable development goals. This objective can be achieved by the application of interdisciplinary and professional approaches through establishing dynamic and optimal balance in supply and demand resources. However, such important optimization approaches have been rarely practiced at the watershed scale. The present study has been therefore formulated to apply a linear water-energy-food nexus optimization for the Shazand watershed, Markazi Province, Iran. This approach was applied for planning 14 crops planted in orchard, irrigated farms, and rain-fed farms, between 2006 and 2014, and targeting water-energy-food nexus index (WEFNI) maximization. The connections among the water, energy, and food were then evaluated through determining the amount of consumption, mass productivity, and economic productivity of water and energy. The results of WEFNIs revealed that almond has the highest WEFNI with values of 0.92, 0.76, 0.76, 0.83, 0.86, 0.86, 0.87, 0.87, and 0.88. Whilst, potato with WEFNI of 0.05, 0.05, 0.05, 0.06, 0.09, 0.10 and 0.11, sugar cane with WEFNI of 0.10 and cucumber with WEFNI of 0.13 had the lowest scores and the corresponding lowest performance among the study crops. The outcomes of optimization study explained that the current situation of land use in the Shazand Watershed is unsuitable to minimize water and energy consumption and maximize benefit. The results can be used as an effective tool for designating proper soil and water resource management strategies in the region.
显示更多 [+] 显示较少 [-]Determination of Cu, Zn and Cd in Soil, Water and Food Products in the Vicinity of RMG Gold and Copper Mine, Kazreti, Georgia 全文
2017
Avkopashvili, Guranda | Avkopashvili, Marika | Gongadze, Alexander | Tsulukidze, Manana | Shengelia, Evgenia
Functioning of polymetallic factories are considerable harming the ecological systems in the environment. Operation of RMG Gold and Copper Mine in the SE part of Georgia causes severe ecological problems in the region. It is vital that conducted monitoring near the areas where industrial activities are underway. The study is aimed at eco-monitoring of the Bolnisi municipality, Georgia. The monitoring was conducted of heavy metals (Cu, Zn, Cd) in system “water-soil-plant” in the area of Kazreti (Madneuli) – villages: Balichi, Ratevani, Naxiduri, Xidiskhuri. According to the results obtained in the soil, content of heavy metals are significantly higher than the allowable concentration limit. In spite of this in crops of the plants which were grown on this soil, content of Cu and Zn does not exceed the allowed concentration limits, Cd content was not found. Study plants were green been, mauhroom, green walnut, green pepper, cucumber, cherry, potato, tomato, walnut, garlic, dry been and corn. Study water were rivers Kazretula and Mashavera's water. Rivers Kazretula and Mashavera water content Zn and Cd concentration.
显示更多 [+] 显示较少 [-]High efficient solid-phase microextraction based on a covalent organic framework for determination of trifluralin and chlorpyrifos in water and food samples by GC-CD-IMS 全文
2022
Tabibi, Alireza | Jafari, Mohammad T.
Novel porous covalent organic framework (COF) based on condensation reaction between cyanuric chloride, 4,4′-ethylendianiline, and 3,4,9,10-perylenetetracarboxylic dianhydride was synthesized via sealed tube condition. The results COF was used as a new adsorbent for solid-phase microextraction (SPME) for extracting trifluralin and chlorpyrifos from vegetables, fruit samples, and wastewater. Gas chromatograph with a corona discharge-ion mobility spectrometer as the detector was also used for analyzing the target analytes. Some parameters that affected the extraction, such as stirring rate, time and temperature of extraction and pH were investigated, exhaustively. The detection limits were 0.13, and 0.15 µg/L and the linear ranges of 0.45–20 and 0.50–25 µg/L with a linearity coefficient of 0.9965 and 0.9987 were also obtained for trifluralin and chlorpyrifos, respectively. The method was applied successfully to analyze some real samples of cucumber, carrot, grape, and agriculture wastewater, and the results showed a relative recovery in the range of 87% to 110%.
显示更多 [+] 显示较少 [-]Alimento consumido por Diaphania hyalinata L. (Lepidoptera: Pyralidae) en pepino (Cucumis sativus L.) y melón de agua (Citrullus lanatus Thunb).Umbral económico en pepino y control en organopónicos
2006
Mora, E., Universidad Central Marta Abreu, Villa Clara (Cuba)
Se realizó un estudio para conocer el consumo de alimento de Diaphania hyalinata (L.) (Lepidoptera; Pyralidae) en los cultivos de pepino (Cucumis sativus L.) y melón de agua (Citrullus lanatus Thunb.) así como el umbral económico y la señalización de esta plaga en organopónicos en el cultivo del pepino. Se establecieron sistemas de control de la misma para saber la efectividad técnica de los nematodos entomopatógenos Heterorhabditis indica cepa P2M y Heterorhabditis sp. cepas Ciap-Dey-6 y Ciap-CIAP-7, la bacteria entomopatógena Bacillus thuringiensis Berliner y el hongo Beauveria bassiana Bálsamo. El consumo de alimento en el estado larval de D. hyalinata resultó ser de 1,27 g en peso y 49,03 cmE2 en área para el melón y 1,14 g en peso y 50,33 cmE2 en área para el pepino. La cantidad de 2,5 larvas/planta es el umbral de daño económico en el cultivo sin cobertor y 5 larvas/planta en el cultivo con cobertor. La emisión de señales para productos químicos en pepino es cuando existen 2 larvas por planta en el cultivo sin cobertor y 4 en el cultivo con cobertor; para productos biológicos 1,5 larvas por planta en el cultivo sin cobertor y 3,5 larvas en el cultivo
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