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Raoult's law based food water sorption isotherm
2000
Lewicki, P.P.
A new model of water sorption isotherm is developed on the basis of Raoult's law. It is assumed that water present in food occurs in two states, as free water with properties of the bulk water and as water of hydration. Hydrated molecules are considered as new entities with molecular weights larger than those of non-hydrated molecules. Hydration reduces the free concentration of water and thus affects water activity in solution. Application of the developed equation to food sorption data showed that it gives approximation of sorption isotherms much better than that offered by the GAB model. Moreover, it predicts infinite adsorption at a(w)=1, the property which is not offered by the GAB equation. The new equation makes it possible to interpolate isotherms at high water activities close to one. The probability that the new equation will fit the food isotherm with small RMS is higher than 90% and substantially exceeds that found for the GAB model. As a two-parameter model it makes substantial improvement over the three-parameter GAB equation.
Show more [+] Less [-]Use of food quotients in human doubly labeled water studies: comparable results obtained with 4 widely used food intake methods
1998
Surrao, J. | Sawaya, A.L. | Dallal, G.E. | Tsay, R. | Roberts, S.B.
Information on the macronutrient composition of the diet is needed in doubly labeled water studies to convert measured rates of carbon dioxide production into values for total energy expenditure. There is no general consensus, however, about the best method to determine food intake for this purpose. Four common methods of measuring food intake (7-day weighed food intake, 24-hour recall, and Fred Hutchinson Cancer Research Center/Block and Willett food frequency questionnaires) were tested for their ability to provide comparable food quotient and total energy expenditure data in doubly labeled water studies in 10 young and 10 older women. All methods gave mean values for total energy expenditure that were within 1% of each other. Individual values obtained using the 24-hour recall and food frequency questionnaires were within +/-3% (standard deviation) of values determined using data from the 7-day weighed food record. These results suggest that it is not necessary to use time-consuming and expensive 7-day food records in doubly labeled water studies; instead, food intake data obtained more easily by 24-hour recall or food frequency questionnaire can provide comparable data.
Show more [+] Less [-]Water quality survey and evaluation of "haodifang" brand citrus green food production base area
2001
Zhao Sidong | Li Youji | Yang Guliang(South Central Forestry College, Zhuzhou (China))
Food safety and quality | Limitations of FDA's bottled water survey and options for better oversight
1992
A model to integrate and assess water-energy-food nexus performance: South Africa case study Full text
2020
t. mabhaudhi | luxon nhamo | s. mpandeli
The main limiting factor impeding the operationalisation of the WEF nexus has been lack of metrics and tools to translate the concept into a fully-fledged operational framework to support policy and decision-making. This study developed a WEF nexus model by (i) defining WEF nexus sustainability indicators, and (ii) calculating composite indices for those indicators to establish numerical relationships among WEF nexus resources using South Africa as a case study. The composite indices show WEF nexus performance as well as monitoring and evaluation of WEF resources management. The indicators were integrated through the Analytic Hierarchy Process (AHP) in a multicriteria decision-making (MCDM). The established quantitative relationships indicate resource utilisation, management and performance through a spider graph to illustrate WEF nexus performance, providing a general overview of the level of interactions, interrelationships and inter-connectedness of resources. The shape of the spider graph is determined by the level of the interdependencies and interactions among the WEF nexus sectors, whose management is viewed either as sustainable or unsustainable depending on the classification of the developed integrated index. The spider graph for South Africa showed an over-emphasis on food self-sufficiency and water productivity at the expense of other sectors. The deformed shape of the spider graph is a demonstration of the sectoral or �??silo�?� approach in resource management. The calculated integrated WEF nexus index of 0.203 for South Africa classified the country under the low sustainability category. The developed model is a decision support tool that provides evidence for interventions in priority areas. The model demonstrates the capabilities of the WEF nexus to evaluate synergies and trade-offs in a systematic and integrated way to increases efficiency and productivity in resource management for sustainable development | Luxon Nhamo, T. Mabhaudhi, S. Mpandeli, 'A model to integrate and assess water-energy-food nexus performance: South Africa case study', pp.10p, 2020
Show more [+] Less [-]Bangladesh: Boosting food security for poor farmers: Netrakona integrated agricultural production and water management project Full text
2004
This document presents the key findings of the evaluation of an integrated agricultural production and water management project implemented by IFAD in Netrakona district, in northern Bangladesh. The aim of this eight-year project was to boost the incomes and food security of small farm households and arrest their decline into marginalisation and landlessness.Outcomes of the project include: sustainable changes have been brought about by the projectimpact surveys show that 85% of respondents now use the skills and knowledge they received from training and will continue to do sobetween 1995 and 2000 the amount of land used to grow vegetables increased by 186% from 2,750 to 8,950 hectaresnew training and community centres facilitate communication on marketing issues or availability of social servicesimplementation was not participatory: greater expertise in participatory development and group mobilisation is needed in future projects of this kindthe potential for livestock development should be given higher priority and where NGOs are involved in government projects more effective coordination between the two is vital.Key insights from the evaluation include:lack of credit for small farmers is a constraint to agricultural development and needs strengtheningparticipation is the key to people-centred development yet it was understood differently by various partners. Greater expertise and knowledge of participatory development and social mobilisation during the planning stages would ensure that sound concepts and implementation strategies are adopted from the outsetstronger project design such as the flexibility to modify project activities during implementation, if necessary, would ensure greater impact.[adapted from author]
Show more [+] Less [-]Evaluation of the relative suitability of various groups of algae as food of milkfish in brackish-water ponds. Full text
1967
HWANG TL | TANG YA
Scientific Opinion on the safety assessment of the active substances, sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulphate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water, for use as active system in food contact materials Full text
2014
EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)
This scientific opinion of EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the active substances sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulfate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water, used in mixture which is packed into sachets for absorbing oxygen/carbon dioxide emitting from/into the headspace surrounding packed food. All substances of this formulation have been evaluated and approved for use as additives in plastic food contact materials or as food additives. No migration of calcium, iron and sodium ions was detected. No volatile organic compounds other than carbon dioxide were detected at the limit of detection of 0.5 μg/l. The CEF Panel concluded that the use of the substances sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulfate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water does not raise a safety concern when used in oxygen absorber/carbon dioxide emitter systems, in sachets that prevent the physical release of their contents into the food. The sachets are to be placed in the headspace of the packaging and as such may come into occasional contact with the food, e.g. during handling. The sachet should not come into direct contact with liquid foods or foods that have and external aqueous liquid phase on the surface (liquid or exudates).
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