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Cynara cardunculus L. (Asteraceae) is a multipurpose crop native to the Mediterranean area, commonly called cardoon. It comprises three botanical varieties: the globe artichoke (var. scolymus (L.) Fiori), the cultivated cardoon (var. altilis DC.), and the wild cardoon (var. sylvestris (Lamk) Fiori). Cardoon can develop in adverse climate conditions, low inputs, high temperature, severe drought, and infertile soils as a resistant species. Yet, it can persist for several years, re-sprouting annually. Cardoon can be used for different purposes due to its composition. For instance, the fleshy stems and the immature heads are used in Mediterranean cuisine. The flowers are used in the production of some cheeses as vegetal rennet. In traditional medicine cardoon is used due to its high content in cynarin and silymarin. Kidneys and liver malfunction, high blood cholesterol levels, diabetes, and cancer are some of the medicinal applications. On the other hand, cardoon’s by-products, leaves, stems and seeds, can be used to produce biomass for energy, biodiesel, seed oil, animal feed and paper pulp. Cardoon’s leaves bioactive properties (e.g.: antioxidant and antimicrobial activities) are due to its excellent polyphenol profile, rich in chlorogenic acid and flavonoids. As leaves represent, on average, about 60% of total cardoon waste, in the context of a circular economy it is essential to take advantage of its composition in bioactive compounds. Concerning the food industry, leaves, and leaves extracts bioactivity may represent an added value as a food additive, as an ingredient in developing a novel food, or in active food packaging to control lipid oxidation and microbial deterioration. Hence, this study aims to address the current food applications of cardoon’s leaves and their functional properties and explore new potential ones adding value to its properties. Acknowledgements: Cássia H. Barbosa thanks the Fundação para a Ciência e Tecnologia (FCT), Portugal for the Ph.D. Grant 2021.08154.BD. N/A

Tese de doutoramento em Engenharia dos Materiais, apresentada ao Instituto Superior técnico da Universidade de Lisboa, 2020. Tese orientada por: Doutora Ana Teresa Sanches Silva (Orientador), Profª Doutora Maria de Fátima Reis Vaz (Co-orientador) The work presented in this thesis was mainly developed at the National Institute of Health Dr. Ricardo Jorge. Some of the chapters of this thesis were carried out in collaboration among the Institute of Polymer and Composites/13N of the University of Minho, Faculty of Pharmacy of the University of Coimbra, Faculty of Pharmacy of the University of Santiago de Compostela (Spain) and the Institute for Polymers, Composites and Biomaterials (IPCB-CNR), Portici, Naples (Italy). Atualmente, a indústria das embalagens alimentares, devido a várias solicitações resultantes da consciencialização dos consumidores sobre questões ambientais, procura soluções "verdes", mais amigas do ambiente no contexto de uma economia sustentável. Infelizmente, o uso de biopolímeros apresenta limitações, uma vez que apresentam propriedades mecânicas e barreira limitativas. Este fato pode ser mitigado adicionando componentes de tamanho nano para formar nanocompósitos. Além destes novos desenvolvimentos, a incorporação de substâncias de extratos naturais nos nanocompósitos pode substituir os aditivos sintéticos utilizados na indústria das embalagens. A dissertação de doutoramento apresentada divide-se em duas partes distintas, em que a primeira aborda a Inovação das Embalagens Alimentares e a segunda a Segurança das mesmas. Este trabalho resulta da compilação de uma série de estudos que dão resposta aos objetivos traçados. Na primeira parte do trabalho, procedeu-se a uma extensa revisão bibliográfica acerca de nanoreforços, nomeadamente acerca da Nanocelulose (CNC) e da argila Montmorillonita (MMT), no âmbito das suas aplicações em embalagens alimentares. Os restantes artigos, traduzem o desenvolvimento e o estudo de filmes bionanocompósitos, suas propriedades estruturais, mecânicas e de barreira e na sua atividade antioxidante. No decorrer destes estudos foram produzidos diferentes filmes com diferentes composições, quer no que se refere à percentagem de nanoreforço utilizado, quer no que se refere à quantidade de extrato de chá verde incorporado. Os diferentes filmes formulados resultaram num filme biopolimérico ativo de ácido polilático/extracto de chá verde (PLA/GTE) e em filmes bionanocompósitos ativos de PLA/CNC, PLA/MMT e PLA/CNC/GTE. É ainda de destacar, que nesta parte do trabalho foi elaborado um filme biodegradável ativo à base de proteína de soro de leite concentrada (WPC) incorporado com extrato de chá verde. Os diferentes filmes produzidos foram caracterizados recorrendo a uma série de técnicas/métodos laboratoriais. Face aos resultados obtidos, no caso dos compósitos PLA/CNC, as imagens de microscopia eletrónica de varrimento (SEM) indicam que as nanopartículas são dispersas homogeneamente na matriz PLA sendo que, a adição de CNC aumenta ligeiramente a percentagem cristalina da matriz polimérica, apesar da sua sinergia com o GTE desencadear uma estrutura aberta que restringe o processo de cristalização. Nos filmes PLA/CNC/GTE, observa-se que com uma maior percentagem de CNC (ou seja, 5%) ocorre a formação de aglomerados de nanocristais, dificultando o nível de dispersão. Todos os nanocompósitos de CNC e CNC/GTE baseados em PLA, quando comparados com o filme de PLA, indicam um efeito positivo nas propriedades de barreira, sendo esse efeito mais evidente para o filme de PLA/2%CNC/1%GTE. O filme de PLA/2%CNC apresenta os melhores resultados de eficácia no que se refere à inibição da oxidação lipídica do alimento modelo testado, salame fatiado. O filme ativo de proteína de soro de leite revelou-se eficaz no atraso da oxidação lipídica até ao 14º dia de armazenamento de amostras de salmão fresco embalado. A segunda parte desta dissertação, centra-se no domínio da Segurança das Embalagens alimentares. É um fato que existe migração de componentes plásticos da embalagem para o alimento, assim sendo, se a migração destes componentes não for controlada adequadamente e se os seus níveis excederem os valores toxicológicos ou legislativos, eles podem produzir efeitos nocivos para a Saúde e afetar as propriedades organoléticas do alimento. O bisfenol A (BPA) é um composto orgânico, com atividade estrogénica, usado para fabricar plásticos de policarbonato e revestimentos de resinas epóxi. Neste trabalho, foi desenvolvido e validado, com sucesso, um método analítico baseado em cromatografia líquida de alta eficiência com deteção de fluorescência (HPLC-FLD) para a determinação de BPA em vegetais enlatados. Estes resultados foram confirmados por cromatografia líquida acoplada a espectrometria de massa (LC-MS/MS). Currently, the food packaging industry, due to several requests resulting from consumer awareness of environmental issues, is looking for "green" solutions, more environmentally friendly in the context of a sustainable economy. Unfortunately, the use of biopolymers has limitations, since they have to limit mechanical and barrier properties. This fact can be mitigated by adding nano-sized components to form nanocomposites. In addition to these new developments, the incorporation of substances from natural extracts into nanocomposites may replace the synthetic additives used in the packaging industry. The doctoral dissertation presented is divided into two distinct parts, in which the first address the Innovation of Food Packaging and the second the Safety thereof. This work results from the compilation of a series of studies that respond to the objectives set. In the first part of the work, an extensive bibliographic review was carried out on nanoreinforces, namely on Nanocellulose (CNC) and Montmorillonite clay (MMT), within the scope of their applications in food packaging. The remaining articles reflect the development and study of bionanocomposite films, their structural, mechanical and barrier properties, and their antioxidant activity. In the course of these studies, different films were produced with different compositions, both in terms of the percentage of nanofiller used and in terms of the amount of green tea extract incorporated. The different formulated films resulted in an active biopolymeric film of polylactic acid / green tea extract (PLA/GTE) and active bionanocomposite films of PLA/CNC, PLA/MMT, and PLA/CNC/GTE. It should also be noted that in this part of the work, an active biodegradable film based on whey protein concentrate (WPC) incorporated with green tea extract was elaborated. The different films produced were characterized using a serie of laboratory techniques/methods. Given the results obtained, in the case of PLA/CNC composites, the scanning electron microscopy (SEM) images indicate that the nanoparticles are dispersed homogeneously in the PLA matrix, with the addition of CNC slightly increasing the crystalline percentage of the polymer matrix, despite synergy with the GTE trigger an open structure that restricts the crystallization process. In the PLA/CNC/GTE films, it is observed that with a higher percentage of CNC (that is, 5%), the formation of clusters of nanocrystals occurs, hindering the level of dispersion. All PLA-based CNC and CNC/GTE nanocomposites, when compared to PLA film, indicate a positive effect on barrier properties, this effect being more evident for PLA/2%CNC/1%GTE film. The PLA/2%CNC film shows the best results in terms of inhibiting the lipid oxidation of the tested model food, sliced salami. The active film of whey protein proved to be effective in delaying lipid oxidation until the 14th day of the storage of fresh packaged salmon samples. The second part of this dissertation focuses on the safety of food packaging. It is a fact that there is a migration of plastic components from the packaging to the food, so if the migration of these components is not adequately controlled and if their levels exceed toxicological or legislative values, they can produce harmful effects on health and affect health. organoleptic properties of the food. Bisphenol A (BPA) is an organic compound, with estrogenic activity, used to manufacture polycarbonate plastics and epoxy resin coatings. In this work, an analytical method based on high-performance liquid chromatography with fluorescence detection (HPLC-FLD) for the determination of BPA in canned vegetables was successfully developed and validated. These results were confirmed by liquid chromatography coupled to mass spectrometry (LC-MS/MS). 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Food Packaging: Main functions (Protection; Increase shelf-life; Maintain organoleptic properties); Non-biodegradable materials. N/A

The development of new packaging materials offering new functionalities and lower environmental impact, is now an urgent need. On one hand, the shelf life extension of packaged products can be an answer to the exponential increase of worldwide demand for food. On the other hand, the increase in the price of crude oil, together with the uncertainty related to its durability, has imposed the necessity to manufacture new structures to replace oil-derived polymers in the future. Finally, consumers' awareness towards environmental issues increasingly pushes industries to look with renewed interest to “green” solutions. Thus, in the last years’ numerous polymers have been exploited to develop biodegradable food packaging materials. The usage of biopolymers has been limited due to the poor mechanical and barrier properties. These properties can be enhanced by adding reinforcing nano-sized compounds to form nanocomposites. Cellulose is probably the most used and well-known renewable and sustainable raw material. The mechanical properties, reinforcing capabilities, abundance, low density and biodegradability of the cellulose nanoparticles make them ideal candidates for the processing of polymer nanocomposites. The present review focuses on the combination of nanocellulose with polymers such as wheat gluten; starch, gelatine; agar; polyvinyl alcohol (PVA); chitosan. The methods of processing, level of incorporation and the enhanced material properties are discussed. Future trends are addressed namely regarding regulations and food industry applications. This work was supported by the research project “Development of methodologies to evaluate polymeric food packaging constituents and determination of their structural and mechanical properties” (2016DAN1289) funded by the National Institute of Health Dr Ricardo Jorge, I.P. (Lisbon, Portugal). N/A

The aim of the conference is to bring together academia and industry to discuss the safety of food packaging as well as the development of new food packaging materials, including active, intelligent and nano concepts. Bio-based materials will be also discussed due to be a growing area of food packaging. Topics: Food Safety & Quality (Physical and chemical hazards: measurement and assessment; Biological hazards: risk and prevention; Mathematical modelling of risk assessment; Evaluation of food spoilage, food quality and shelf life; Food packaging laws and regulations; Food package interactions: migration measurement methods, models and food safety risk assessment; Food Packaging innovation (Active and intelligent packaging; Nano-packaging; New packaging materials and material development; Bio based and edible packaging; Food package testing; Sustainable food contact materials; Recycling and Life Cycle Assessment).