975 resultados para Product safety.
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The principal objective of this thesis was to investigate the ability of reversible optical O2 sensors to be incorporated into food/beverage packaging systems to continuously monitor O2 levels in a non-destructive manner immediately postpackaging and over time. Residual levels of O2 present in packs can negatively affect product quality and subsequently, product shelf-life, especially for O2-sensitive foods/beverages. Therefore, the ability of O2 sensors to continuously monitor O2 levels present within food/beverage packages was considered commercially relevant in terms of identifying the consequences of residual O2 on product safety and quality over time. Research commenced with the development of a novel range of O2 sensors based on phosphorescent platinum and palladium octaethylporphyrin-ketones (OEPk) in nano-porous high density polyethylene (HDPE), polypropylene (PP) polytetrafluoroethylene (PTFE) polymer supports. Sensors were calibrated over a temperature range of -10°C to +40°C and deemed suitable for food and beverage packaging applications. This sensor technology was used and demonstrated itself effective in determining failures in packaging containment. This was clearly demonstrated in the packaging of cheese string products. The sensor technology was also assessed across a wide range of packaged products; beer, ready-to-eat salad products, bread and convenience-style, muscle-based processed food products. The O2 sensor technology performed extremely well within all packaging systems. The sensor technology adequately detected O2 levels in; beer bottles prior to and following pasteurisation, modified atmosphere (MA) packs of ready-to-eat salad packs as respiration progressed during product storage and MA packs of bread and convenience-style muscle-based products as mycological growth occurred in food packs over time in the presence and absence of ethanol emitters. The use of the technology, in conjunction with standard food quality assessment techniques, showed remarkable usefulness in determining the impact of actual levels of O2 on specific quality attributes. The O2 sensing probe was modified, miniaturised and automated to screen for the determination of total aerobic viable counts (TVC) in several fish species samples. The test showed good correlation with conventional TVC test (ISO:4833:2003), analytical performance and ruggedness with respect to variation of key assay parameters (probe concentration and pipetting volume). Overall, the respirometric fish TVC test was simple to use, possessed a dynamic microbial range (104-107 cfu/g sample), had an accuracy of +/- one log(cfu/g sample) and was rapid. Its ability to assess highly perishable products such as fish for total microbial growth in <12 hr demonstrates commercial potential.
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Agri-food supply chains extend beyond national boundaries, partially facilitated by a policy environment that encourages more liberal international trade. Rising concentration within the downstream sector has driven a shift towards “buyer-driven” global value chains (GVCs) extending internationally with global sourcing and the emergence of multinational key economic players that compete with increase emphasis on product quality attributes. Agri-food systems are thus increasingly governed by a range of inter-related public and private standards, both of which are becoming a priori mandatory, especially in supply chains for high-value and quality-differentiated agri-food products and tend to strongly affect upstream agricultural practices, firms’ internal organization and strategic behaviour and to shape the food chain organization. Notably, increasing attention has been given to the impact of SPS measures on agri-food trade and notably on developing countries’ export performance. Food and agricultural trade is the vital link in the mutual dependency of the global trade system and developing countries. Hence, developing countries derive a substantial portion of their income from food and agricultural trade. In Morocco, fruit and vegetable (especially fresh) are the primary agricultural export. Because of the labor intensity, this sector (especially citrus and tomato) is particularly important in terms of income and employment generation, especially for the female laborers hired in the farms and packing houses. Hence, the emergence of agricultural and agrifood product safety issues and the subsequent tightening of market requirements have challenged mutual gains due to the lack of technical and financial capacities of most developing countries.
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"March 1976"--P. [i].
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Mode of access: Internet.
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Shipping list no.: 94-0351-P.
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An estimated 200 Queensland children under 5 years of age are injured every year in incidents involving prams or strollers. The majority of injuries are due to falls from or falls with the pram or stroller Nineteen children were identified as having been caught in the pram or stroller mechanism (13 sustained finger injuries). Stairs and escalators were a factor in nearly 10 percent of pram or stroller fall injuries, with children being tipped out of the pram or stroller, or rolling down the stairs in the device. Roll away injuries accounted for eight percent of all pram or stroller fall injuries (some also involving stairs) Roll away injuries could be prevented by a default brake system similar to airport trolleys. Pram or stroller failure was identified in 2% of injuries
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In the past few years, plant biotechnology has gone beyond traditional agricultural production of food, feed and fibre, and moved to address more complex contemporary health, social and industrial challenges. The new era involves production of novel pharmaceutical products, speciality and fine chemicals, phytoremediation and production of renewable energy resources to replace non-renewable fossil fuels. Plants have been shown to provide a genuine and low-cost alternative production system for high-value products. Currently, the principal plant-made products include antibodies, feed additives, vaccine antigens and hormones for human and animal health, and industrial proteins. Despite the unique advantages of scalability, cost and product safety, issues of politics, environmental impact, regulation and socioeconomics still limit the adoption of biopharmaceuticals, especially in the developing world. Plant-based production systems have further complicated biosafety, gene flow and environmental impact assessments with generally genetically modified plants, topics that are already partially understood. This article provides a background to biopharming, highlighting basic considerations for risk assessment and regulation in developing countries, with an emphasis on plant-based vaccine production in South Africa.
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农药对产地环境,特别是对土壤的广泛污染严重威胁农产品安全和人类健康。因此,本文采用建立的除草剂和有机氯农药(OCPs)残留分析方法,开展了辽北地区土壤农药残留特征、阿特拉津和乙草胺田间消解动力学、土壤农药残留对农产品安全影响等方面研究。主要研究结果如下: 1. 分别建立了土壤、大米、蔬菜、玉米中3种除草剂和8种OCPs多残留分析方法。方法检出限介于0.04~1.30 ng•g-1之间;11种农药在0.01 (0.02)~1.0 (2.0) mg•L-1范围内线性良好,相关系数介于0.9963-0.9998之间;平均回收率介于71%-117%之间、相对标准偏差小于14.4%。 2. 阿特拉津和乙草胺在辽北农田土壤普遍残留;丁草胺、六氯苯、狄氏剂和艾氏剂在部分土壤有残留;乙草胺和丁草胺相对其它农药残留较高;阿特拉津、六氯苯、狄氏剂和艾氏剂残留量与相关报道和标准相比较低。除艾氏剂外,检出农药残留量经Box-Cox变换后,均服从正态分布。阿特拉津、乙草胺、丁草胺、六氯苯在不同土壤利用类型之间存在显著差异(P<0.05)。 3. 玉米地土壤中阿特拉津和乙草胺消解动态符合一级反应动力学模式,阿特拉津消解半衰期在12.2~59.8d之间,乙草胺在18.5~54.6d之间。喷施地阿特拉津和乙草胺消解速率约为对照地的2~5倍,且喷施量越大,消解越快。 4. 11种农药在辽北蔬菜、大米、玉米中残留较低,仅阿特拉津、六氯苯、乙草胺和丁草胺在部分农产品中有残留,其在土壤中残留通过蔬菜、大米和玉米给消费者带来的总膳食风险较低。大田试验进一步说明在试验区域喷施4倍最大推荐剂量阿特拉津或乙草胺也不会对玉米安全产生影响。
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Food product safety is one of the most promising areas for the application of electronic noses. The performance of a portable electronic nose has been evaluated in monitoring the spoilage of beef fillet stored aerobically at different storage temperatures (0, 4, 8, 12, 16 and 20°C). This paper proposes a fuzzy-wavelet neural network model which incorporates a clustering pre-processing stage for the definition of fuzzy rules. The dual purpose of the proposed modeling approach is not only to classify beef samples in the respective quality class (i.e. fresh, semi-fresh and spoiled), but also to predict their associated microbiological population directly from volatile compounds fingerprints. Comparison results indicated that the proposed modeling scheme could be considered as a valuable detection methodology in food microbiology
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In recent years, several studies have linked sodium intake to hypertension, and the consequent mortality risk due to vascular diseases. Several UE member states and the WHO recommend reducing the salt intake level to a maximum of 5 g per day. Salt is a useful ingredient for meat product processing. A reduction of added salt provokes a decrease in the quality of meat products. As a technological strategy, the reduction of the amount of added salt and the addition of potassium lactate, until a 30% molar substitution (taking into account the salt standard amount (30 g/kg)), have been proposed. This substitution could modify the product evolution during its processing. The knowledge of these effects could make the optimization of the process easier. In dry-cured meat products with a reduced salt content, it could be concluded that the proposed strategy reduces the processing period, as well as the anomalous texture risk; it increases the product safety and it does not modify the visual attributes.
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Despite efforts to the contrary, some cosmetic products can cause undesirable side effects in the users. These may often be due to individual factors or inappropriate use of the product. Thus, biological assays to assess the safety of a new cosmetic must precede its being placed on the market. Historically, these tests have always been carried out in vivo, in animals, since such tests can be used to evaluate many of the potential risks, such as irritation, allergy or systemic effects; but, recently, some research centers have been adopting in vitro alternatives, in order to replace the animal tests. This review emphasizes the need to employ biological assays to test the safety of cosmetic products, and reviews the main in vivo and in vitro tests used, focusing on the need to develop and use alternatives to the in vivo assays of product safety, so as to offer the consumers the maximum safety with the least possible risk, while ensuring the best conditions of use of the product.
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Pós-graduação em Bases Gerais da Cirurgia - FMB