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Why chlorate occurs in potable water and processed foods: a critical assessment and challenges faced by the food industry Полный текст
2016
Kettlitz, Beate | Kemendi, Gabriella | Thorgrimsson, Nigel | Cattoor, Nele | Verzegnassi, Ludovica | Le Bail-Collet, Yves | Maphosa, Farai | Perrichet, Aurélie | Christall, Birgit | Stadler, Richard H.
Recently, reports have been published on the occurrence of chlorate mainly in fruits and vegetables. Chlorate is a by-product of chlorinating agents used to disinfect water, and can be expected to be found in varying concentrations in drinking water. Data on potable water taken at 39 sampling points across Europe showed chlorate to range from < 0.003 to 0.803 mg l –¹ with a mean of 0.145 mg l –¹. Chlorate, however, can also be used as a pesticide, but authorisation was withdrawn in the European Union (EU), resulting in a default maximum residue limit (MRL) for foods of 0.01 mg kg –¹. This default MRL has now led to significant problems in the EU, where routinely disinfected water, used in the preparation of food products such as vegetables or fruits, leaves chlorate residues in excess of the default MRL, and in strict legal terms renders the food unmarketable. Due to the paucity of data on the chlorate content of prepared foods in general, we collated chlorate data on more than 3400 samples of mainly prepared foods, including dairy products, meats, fruits, vegetables and different food ingredients/additives. In total, 50.5% of the food samples contained chlorate above 0.01 mg kg –¹, albeit not due to the use of chlorate as a pesticide but mainly due to the occurrence of chlorate as an unavoidable disinfectant by-product. A further entry point of chlorate into foods may be via additives/ingredients that may contain chlorate as a by-product of the manufacturing process (e.g. electrolysis). Of the positive samples in this study, 22.4% revealed chlorate above 0.1 mg kg –¹. In the absence of EU levels for chlorate in water, any future EU regulations must consider the already available WHO guideline value of 0.7 mg l –¹ in potable water, and the continued importance of the usage of oxyhalides for disinfection purposes.
Показать больше [+] Меньше [-]Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste Полный текст
2016
Paini, Marco | Casazza, Alessandro A. | Aliakbarian, Bahar | Perego, Patrizia | Binello, Arianna | Cravotto, Giancarlo
The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.
Показать больше [+] Меньше [-]The effect of copper from water and food: changes of serum nonceruloplasmin copper and brain's amyloid-beta in mice Полный текст
2016
Wu, Min | Han, Feifei | Gong, Weisha | Feng, Lifang | Han, Jianzhong
Copper is an essential element and also produces adverse health consequences when overloaded. Food and water are the main sources of copper intake, however few studies have been conducted to investigate the difference between the ways of its intake in water and food in animals. In this study, copper was fed to mice with food as well as water (two groups: water and diet) for three months at concentrations of 6, 15 and 30 ppm. The copper concentration in water was adjusted for keeping the same amount during its intake in food. The experimental studies show a slow growth rate, lower hepatic reduced glutathione (GSH)/superoxide dismutase (SOD) activity and higher serum ‘free’ copper in the water group. The brain's soluble amyloid-beta 1-42 (Aβ₄₂) of the water group was significantly higher than that of the diet group at the levels of 6 and 15 ppm. In conclusion, copper in the water group significantly increased the soluble Aβ₄₂ in the brain and the ‘free’ copper in the serum, decreased the growth rate and hepatic GSH/SOD activity. The research studies carried out suggest that the copper in water is more ‘toxic’ than copper in diet and may increase the risk of Alzheimer's disease (AD).
Показать больше [+] Меньше [-]Sub- and supercritical water hydrolysis of agricultural and food industry residues for the production of fermentable sugars: A review Полный текст
2016
Prado, Juliana M. | Lachos-Perez, Daniel | Forster-Carneiro, Tânia | Rostagno, Mauricio A.
Bioethanol has been researched as a potential alternative to substitute liquid fossil fuels due to its eco-friendly characteristics and relatively low production cost when compared to other bio-based fuels. First generation bioethanol is produced from raw materials rich in simple sugars or starch, such as sugarcane and corn, which are food sources. To avoid the fuel versus food dilemma, second generation bioethanol aims at using non-edible raw materials, as lignocellulosic agricultural residues, as source of fermentable sugars. Hydrolysis with sub/supercritical water has demonstrated great potential to decompose the lignocellulosic complex into simple sugars with several advantages over conventional processes. This review provides an overview of the state of the art on hydrolysis with sub- and supercritical water in the context of the reuse of agricultural residues to produce suitable fermentation substrates for the production of second generation bioethanol. Recent applications and advances are put into context together, providing an insight into future research trends.
Показать больше [+] Меньше [-]A methodology to assess the impact of climate variability and change on water resources, food security and economic welfare Полный текст
2016
Gohar, Abdelaziz A. | Cashman, Adrian
The potential impacts of climate variability and change on water resources and food security are receiving growing attention especially in regions that face growing challenges meeting water demands for agricultural, domestic and environmental uses. Rainfed agriculture regions exhibit higher vulnerability to climate variability and change, where aquifer storage and food security are under stress. Little research has attempted to investigate the consequences of climate variability and change on water availability and social livelihoods jointly. Employing available data on precipitation, farm budget data, and aquifer characteristics, a dynamic nonlinear optimization framework that maximizes the economic likelihoods of irrigation activities and food security under several climatic assumptions is developed and applied for Barbados as a numerical example. Our framework accounts for technological adaptation measure, drip irrigation, with the context of variable yield and cost of water demand under governmental subsidy schemes. Results indicate significant negative impacts of climate variability, change, and double exposure on future water resources and food security. However, some climate assumptions provide opportunity for some food producers who respond positively to technological adaptation programs, while consumers could face the major negative consequences by experiencing higher food prices. Our findings provide policymakers and stakeholders a comprehensive tool for economically efficient and sustainably reliant policy design, implementation, and evaluation facing the potential climate variability and change impacts.
Показать больше [+] Меньше [-]Food grade water-in-oil microemulsions as replacement of oil phase to help process and stabilization of whipped cream Полный текст
2016
Mitsou, Evgenia | Tavantzis, George | Sotiroudis, George | Ladikos, Dimitris | Xenakis, Aristotelis | Papadimitriou, Vassiliki
Food grade W/O microemulsions were developed and characterized to be used in blends with sunflower oil as replacers of palm kernel oil in whipped cream alternatives. Creams for whipping are oil-in-water (O/W) emulsions containing significant proportions of partially hydrogenated solid fat. With the addition of sunflower oil and W/O microemulsions up to 6.8% w/w in the final confectionary product we achieved the decrease of saturated fats and also the decrease of the energy required for the formulation. More specifically, by replacing 20% w/w of the oil phase by the proposed edible W/O microemulsions, the homogenization time was reduced from 7 to 5min under the same experimental conditions. In addition solid fat partial replacement permitted the modification of structural and textural characteristics. Droplet size and size distribution measurements were performed using dynamic light scattering (DLS). The existence of rather polydisperse oil droplets with diameters of approximately 1μm upon palm kernel oil partial replacement was detected. Structural characterization of the proposed alternative systems with confocal laser scanning microscopy (CLSM) showed the existence of air bubbles of diameter 6–94μm stabilized by globular oil droplets having diameters ranging from 4.2 to 5.9μm adhered to their surface. Firmness and consistency of the proposed alternative formulations were evaluated using a Stevens-texture analyzer. As a result emulsions after whipping gave products with lower density (362±9g/mL) but higher consistency (208±7g) as compared to the standard whipped cream preparation (150±5g).
Показать больше [+] Меньше [-]Produção de hortaliças com água de chuva armazenada em cisternas melhora a dieta alimentar das famílias rurais. Полный текст
2016
BRITO, L. T. de L. | CAVALCANTI, N. de B. | COSTA, N. D.
Toxicity and transfer of polyvinylpyrrolidone-coated silver nanowires in an aquatic food chain consisting of algae, water fleas, and zebrafish Полный текст
2016
Chae, Yooeun | An, Youn-Joo
Nanomaterials of various shapes and dimensions are widely used in the medical, chemical, and electronic industries. Multiple studies have reported the ecotoxicological effects of nanaoparticles when released in aquatic and terrestrial ecosystems; however, information on the toxicity of silver nanowires (AgNWs) to freshwater organisms and their transfer through the food webs is limited. In the present study, we aimed to evaluate the toxicity of 10- and 20-μm-long AgNWs to the alga Chlamydomonas reinhardtii, the water flea Daphnia magna, and the zebrafish and study their movement through this three-species food chain using a variety of qualitative and quantitative methods as well as optical techniques. We found that AgNWs directly inhibited the growth of algae and destroyed the digestive organs of water fleas. The results showed that longer AgNWs (20μm) were more toxic than shorter ones (10μm) to both algae and water fleas, but shorter AgNWs were accumulated more than longer ones in the body of the fish. Overall, this study suggests that AgNWs are transferred through food chains, and that they affect organisms at higher trophic levels, potentially including humans. Therefore, further studies that take into account environmental factors, food web complexity, and differences between nanomaterials are required to gain better understanding of the impact of nanomaterials on natural communities and human health.
Показать больше [+] Меньше [-]Anaylsing the economic development impact of semi-arid lands, and mitigation through food-trade water recource decoupling Small grants programme Полный текст
2016
Gilmont, Michael
This work was carried out under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA), with financial support from the UK Government’s Department for International Development (DfID) and the International Development Research Centre (IDRC), Canada. | This research examines the relationship between semi-arid lands and national economic development, and the potential of food/agricultural trade to buffer semi-arid land vulnerability and mitigate water scarcity. It investigates a key assumption in development thinking – that water limits in semi-arid areas constrain economic growth. The research findings question whether future investment should be targeted at semi-arid lands directly, or whether wider national institutional and capacity considerations, including food trade, should be given more attention as a means of mitigating the vulnerability of people, land and economies to climate change.
Показать больше [+] Меньше [-]Sustaining food self-sufficiency of a nation: The case of Sri Lankan rice production and related water and fertilizer demands Полный текст
2016
Davis, Kyle F. (Kyle Frankel) | Gephart, Jessica A. | Gunda, Thushara
Rising human demand and climatic variability have created greater uncertainty regarding global food trade and its effects on the food security of nations. To reduce reliance on imported food, many countries have focused on increasing their domestic food production in recent years. With clear goals for the complete self-sufficiency of rice production, Sri Lanka provides an ideal case study for examining the projected growth in domestic rice supply, how this compares to future national demand, and what the associated impacts from water and fertilizer demands may be. Using national rice statistics and estimates of intensification, this study finds that improvements in rice production can feed 25.3 million Sri Lankans (compared to a projected population of 23.8 million people) by 2050. However, to achieve this growth, consumptive water use and nitrogen fertilizer application may need to increase by as much as 69 and 23 %, respectively. This assessment demonstrates that targets for maintaining self-sufficiency should better incorporate avenues for improving resource use efficiency.
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