Acetaldehyde generation in preforms with the use of recycled PET

Dissertação de mestrado integrado em Engenharia de PolímerosThe production and recycling process for polyethylene terephthalate (PET) bottles for packaging soft drinks and mineral waters is still growing worldwide and improving constantly. Although, during the melting and processing of PET, especially recycled PET (rPET), degradation of the material occurs. The result of the degradation reactions is a severe drop in the molecular weight, which leads to the failing of intrinsic viscosity, melt strength and melt processability and finally, to poor usage properties and a low quality of the bottles obtained. One of the most common degradation products is acetaldehyde (AA). Due to its low boiling point, 21°C, AA is able to diffuse out of PET into the beverage content of the PET bottle. The diffusion of AA into packaged contents is of concern due to its limited threshold for the taste and odour that can be detected by consumers. The purpose of this study is to examine the AA generation, the failing of the intrinsic viscosity and the colour degradation from reprocessed rPET when exposed to different drying and injection conditions. An initial model was developed to analyse the interaction, magnitude and influence of each processing condition in a twin-tower desiccant dryer and a mono-cavity PET preform injection moulding system. It was found an optimal condition capable of reducing AA concentration in the preform, without compromising a significant failing of the intrinsic viscosity, with minimal impact in colour degradation. The modification of an existing drying and injection moulding program was applied under the optimal result given by the model and additional studies regarding moisture content and intrinsic viscosity were conducted. AA was reduced by 61% after drying, while the drop in the intrinsic viscosity was significantly reduced by heat preservation of the settled drying temperature. There was no significant impact in colour observed. An agreement between the modelling results and observed trends from mono-cavity injection moulding was achieved. The groundwork was placed and made further improvements in the industrial production of preforms containing 100% content of recycled PET.O processo de produção e reciclagem de garrafas em polietileno tereftalato (PET) em vários continua a crescer exponencialmente, fruto de um processo de aperfeiçoamento constante. No entanto, aquando do seu processamento e transição para o estado fundido, ocorre degradação do material, particularmente quando se utiliza PET reciclado (rPET). O resultado das reações de degradação traduz-se numa queda acentuada no peso molecular, levando a uma falha na viscosidade intrínseca, resistência do fundido e processabilidade do mesmo. Por consequência, a degradação do material nestas condições resulta em pobres qualidades do material em serviço e uma baixa qualidade das garrafas obtidas. Um dos produtos de degradação mais comuns é o acetaldeído (AA). Devido ao seu baixo ponto de ebulição, 21 ° C, o AA é capaz de se difundir do PET para o conteúdo da garrafa. Este processo de difusão de AA é preocupante porque altera o sabor e odor do conteúdo embalado e pode ser facilmente detetados pelos consumidores. O objetivo deste estudo é examinar a geração de AA, a falha na viscosidade intrínseca e a degradação de cor do rPET quando exposto a diferentes condições de secagem e moldação por injeção. Um modelo estatístico inicial foi desenvolvido para analisar a interação, magnitude e influência de cada condição de processamento de um sistema de moldagem por injeção e de secagem de dois tipos de rPET na produção de pré-formas. Foi encontrada uma condição ótima capaz de reduzir a concentração de AA na pré-forma, sem comprometer uma falha significativa da viscosidade intrínseca, com impacto mínimo na degradação da cor. A modificação das condições existentes de secagem e moldagem por injeção foi aplicada sob o resultado ótimo obtido pelo modelo, onde estudos adicionais sobre o teor de humidade e viscosidade intrínseca foram posteriormente realizados. O AA foi reduzido em 61% após a secagem e a queda na viscosidade intrínseca foi significativamente reduzida pela preservação da temperatura de secagem estabelecida. Não houve impacto significativo na cor observada. Atingiu-se um compromisso entre os resultados do programa estatístico e as tendências observadas na moldagem por injeção. A base foi lançada e foram feitas novas melhorias na produção industrial de pré-formas com 100% de teor de PET reciclado

Fashion Made in China, the leverage to succeed or the doom to fail in the globalized world

Context of study: The rise of China’s labor costs, and the fact that lower-wage countries have now manufacturing capacity, has pushed domestic apparel manufacturers to emphasize on two more profitable sectors: product development, and retail. This reflects a shift from Original Equipment Manufacturer (OEM) to Original Brand Manufacturer (OBM), which brings challenges for the Chinese apparel companies, since domestic apparel manufacturers didn’t invest much in product development and design ability. Chinese fashion retailers do not play a leading role in the global industry, having only a few influential international brands. However, efforts have been made in order to innovate their merchandise distribution channels and improve promotion policies, to frame the domestic retail networks, appealing to consumers’ attention, and attain market share (Li 2002). Statement of Purpose: The aim of this paper is to firstly identify the difficulties that these private labels can face due to the typical Chinese consumer profile that is characterised by high spenders in haute couture in foreign markets rather than in the domestic market. Secondly, this phenomena might influence these private label brands to expand to international markets, which creates new difficulties due to the world’s perception of the low quality of products manufactured in China. Finally, how these Chinese private-label companies will create a brand equity, in domestic and foreign markets, in order to positioning themselves in the fashion market. Methodology: A multiple case study involving three Chinese apparel companies was employed. The information collected had as final aim, to apply each company to a Porter’s framework, and realize if they gathered the sustained competitive advantage factors necessary to succeed according to its strategy adopted. Contribution: This study has attempted to contribute to the research field of types of strategy and firm performance within an industry recent trend. Hence, the findings in this study should provide a criticism to Porter’s theory of sustained competitive advantage factors and firm’s type of strategy, in the sense that companies can perform well, even when they pursue more than one type of strategy, or when they don’t accomplish all necessary factors, stated by Porter, to achieve competitive advantage

Modulation of aroma volatiles and phytochemical quality of fresh-cut melon (Cucumis melo L.) by oxygen levels, 1-methylcyclopropene and lysophosphatidylethanolameine

Current fresh-cut technologies are effective in the effort of maintaining visual quality during the fresh-cut fruit supply chain. However, studies on extended shelf life based on appearance attributes or microbial stability have neglected the understanding of the effect of processing technologies and conservation techniques in the aromatic, nutritional, and functional properties of processed fruit. Three technologies were evaluated for their effects on quality of fresh-cut melon, with emphasis on aroma volatiles: oxygen levels, the ethylene action inhibitor 1-methylcyclopropene (1-MCP), and lysophosphatidylethanolamine (LPE), an inhibitor of phospholipase D (PLD). Modified atmosphere packaging (MAP) is widely used in fresh-cut fruit, with the objective of extending shelf-life. Nevertheless, MAP requirements and recommendations for fresh-cut fruit target mostly color and texture maintenance, neglecting the effects on aroma production. In this thesis, the quality attributes and aroma production of fresh-cut melon were monitored during MAP storage. Cantaloupe and honeydew melon cultivars were processed into cubes and stored at 5 ºC under high passive MAP or reduced controlled atmosphere (CA; 5 kPa O2 + 10 kPa CO2, balance N2). Oxygen levels during storage had a greater impact on aroma than on other quality attributes during storage of fresh-cut climacteric and non-climacteric melon. Cantaloupe and honeydew melon flavor-important volatiles were differently affected by oxygen levels inside the packages. Also, storage time had a significant effect on volatile production of fresh-cut cantaloupe and honeydew melons. 1-MCP application to whole fruit, its effects on quality, ethylene production and perception have been the subject of many studies. In contrast, fewer studies have focused on 1-MCP application to fresh-cut fruit. For its known inhibitory effect on ethylene production, we anticipated 1-MCP to have beneficial effects on some quality attributes of fresh-cut melon, while altering aroma profile. The effect of 1-MCP application in quality and synthesis of flavor-important volatile compounds in melon was evaluated during storage of fresh-cut cantaloupe. Cantaloupe melons were processed and treated with 1.0 μL L-1 of 1-MCP, for 24 h at 5 ºC, packaged in vented plastic clamshells and stored under normal atmosphere at 5 ºC for 9 days. Treatment with 1-MCP did not affect the main quality attributes of fresh-cut melon, but affected nine of the flavor-important volatiles, particularly those with isoleucine and phenylalanine as precursors. 1-MCP affected fresh-cut cantaloupe production of propyl acetate, 2-methylbutyl acetate, methyl butanoate, methyl 2-methyl butanoate, methyl hexanoate, 2-methylbutyl alcohol, phenethyl alcohol, benzyl alcohol and heptanal. LPE is reported to inhibit PLD activity, reduce ethylene production, and extend shelf-life of many horticultural commodities. Therefore, LPE could provide a novel treatment to improve the quality of fresh-cut fruit, via maintenance of membrane integrity and reduction of the wound response. The effect of LPE on PLD activity, quality and volatile production of fresh-cut melon was investigated during storage. Charentais-type melons were processed into cubes and vacuum-infiltrated with 200 mg L-1 of LPE, packaged in plastic clamshells and stored at 5 ºC for 9 days. LPE was not effective in maintaining overall quality of fresh-cut melon but induced a reduction of aldehydes production in the first three days of storage. LPE inhibited PLD activity in the first day after processing, which may have induced the reduction of aldehydes observed at day three of storage of fresh-cut melon. In conclusion, oxygen levels significantly affect the volatile profile of fresh-cut melon, and there may be opportunity to optimize oxygen recommendation for aroma preservation. 1-MCP and LPE altered the volatile profile of fresh-cut melon but had minimal or no effect on other quality attributes

Availability and information needs in the chemical contaminants domain – PortFIR assessment

Chemical contaminants (Chc) can be naturally present and/or be introduced in food and feed as result of the various stages of its production, processing and transport and/or due to environmental contamination. The analysis of Chc laboratory data allows to generate information for continuous improvement of food safety and protection of public health. In order to define priorities for development of the Contaminants Database of the Portuguese Food Information Resource (PortFIR), it was decided to identify and assess the availability and information needs on food and feed Chc of the main Portuguese stakeholders in the area.N/

PortFIR – An integrated data provider as support for the food policy-makers

Introduction: Portuguese Food Composition Table (TCA) is managed by the National Institute of Health Doutor Ricardo Jorge (INSA) and is publicly available on the Portuguese Food Information Resource (PortFIR) platform. PortFIR, besides food composition data, was designed to include data on food contamination and food consumption, in order to provide national data easily available in one platform. Objective:To compile and make widely available food-related data (food composition, food safety and food consumption), while providing science-based information, to support food policy-makers.info:eu-repo/semantics/publishedVersio

Food Composition Table user’s utilization and needs PortFIR assessment

Food composition tables (FCT) and databases (FCDB) are very important data resources that can contribute to the achievement of health gains through the improvement of knowledge and nutritional status of the population and the promotion of healthy eating, however they are far from complete. Therefore, a continuous development and update of these resources, with great focus in their user’s needs, should be considered a priority. Objectives: To identify and assess the type of utilization and needs of the Portuguese FCT/FCDB (TCA) user’s, in order to define priorities for its development and update.info:eu-repo/semantics/publishedVersio

Inclusão profissional, participação comunitária e qualidade de vida

Na realização deste texto está a ideia de que a obtenção de um emprego para as pessoas com Deficiência Intelectual (DI) deve contribuir para melhorar a qualidade de vida, i.e., aumentar o bem-estar geral (físico, material e emocional). Neste caso analisou-se, a partir de uma amostra de 36 trabalhadores com DI, para determinar, compreender e explicar o mais aprofundadamente possível como é que, no tempo pós-inclusão no mercado de trabalho, se encontrava estruturada a participação comunitária, tendo especialmente em atenção atividades que decorrem das relações sociais e interpessoais. A abordagem teórica seguiu um registro microssociológico, e os dados usados foram recolhidos por meio de uma metodologia de vertente predominantemente qualitativa, com recurso a entrevistas e à observação direta. Os níveis de participação encontrados no estudo seguem um padrão que se pode ligar ao rendimento e ao capital cultural das famílias. As modalidades de participação mais praticadas são as que não exigem especiais competências e em que o custo pode ser reduzido e como tal suportável financeiramente. Existem, porém, diferenças muito sensíveis segundo o gênero. O nível global de participação das mulheres é mais reduzido que o dos homens, sobretudo nas atividades que implicam sair do espaço residencial ou exigem maior dispêndio monetário

Gene expression regulation by upstream open reading frames in rare diseases

Upstream open reading frames (uORFs) constitute a class of cis-acting elements that regulate translation initiation. Mutations or polymorphisms that alter, create or disrupt a uORF have been widely associated with several human disorders, including rare diseases. In this mini-review, we intend to highlight the mechanisms associated with the uORF-mediated translational regulation and describe recent examples of their deregulation in the etiology of human rare diseases. Additionally, we discuss new insights arising from ribosome profiling studies and reporter assays regarding uORF features and their intrinsic role in translational regulation. This type of knowledge is of most importance to design and implement new or improved diagnostic and/or treatment strategies for uORF-related human disorders.This work was partially supported by Fundação para a Ciência e a Tecnologia (UID/MULTI/04046/2013 to BioISI from FCT/MCTES/PIDDAC). JS and RF are supported by fellowships from Fundação para a Ciência e a Tecnologia (SFRH/BD/106081/2015 and SFRH/BD/114392/2016, respectively).info:eu-repo/semantics/publishedVersio