Dissertations / Theses on the topic '3D food printing'

La stampa 3D degli alimenti rappresenta una tecnologia innovativa ed emergente capace di costruire un oggetto tridimensionale partendo da un modello CAD creato su software di disegno grafico. Durante gli ultimi anni molti studi hanno dimostrato come questa tecnologia sia stata applicata per la produzione di alimenti nuovi. L’obiettivo principale di questa tesi è stato l’approfondimento e il miglioramento della tecnologia di stampa 3D nel settore alimentare contribuendo alla creazione di alimenti dalle proprietà mai esplorate prima. Dopo un’analisi dell’evoluzione temporale della tecnologia di stampa 3D nel settore alimentare, una varietà di altri aspetti sono stati studiati, tra cui la capacità di creare e modificare alimenti dalle nuove texture attraverso la progettazione di nuovi design, inoltre è stata oggetto di studio la stampa 3D ad alta velocità, tema interessante dal punto di vista dell’applicazione in campo industriale. Gli studi si sono focalizzati sull’utilizzo di due diverse matrici di stampa: impasto a base di cereali e gel a base d’amido, stampando strutture geometriche (cubi, parallelepipedi) e design ispirati alla natura (tessuti interni delle mele). La tesi è strutturata in 8 capitoli: una breve introduzione (capitolo 1), obiettivi e linee di ricerca (capitolo 2) e altri cinque capitoli corrispondenti alle 5 pubblicazioni su riviste internazionali; Drawing the scientific landscape of 3D Food Printing. Maps and interpretation of the global information in the first 13 years of detailed experiments, from 2007 to 2020’(capitolo 3) and ‘Rheological properties, dispensing force and printing fidelity of starchy-gels modulated by concentration, temperature and resting time’ (capitolo 4). I capitoli 5 e 6 sono dedicati alla creazione di alimenti stampati in 3D con proprietà meccaniche desiderate e personalizzabili: Programmable texture properties of cereal-based snack mediated by 3D printing technology’ (capitolo 5), ‘Extending 3D food printing application. Apple tissues microstructure as CAD model to create innovative cereal-based snacks’ (capitolo 6). Il capitolo 7 si è focalizzato sulla stampa 3D ad alta velocità: ‘Extending the 3D food printing tests at high speed. Material deposition and effect of non-printing movements on the final quality of printed structures’. E infine il capitolo 8 racchiude le conclusioni e alter discussioni generali riguardanti la tesi.
3D printing (3DP) represents an innovative and emerging technology aiming to build three-dimensional objects starting from the computer-aided model. During last years main studies showed the application of this technology to produce innovative foods. The main aim of this research was the better understanding and the implementation of 3D Printing in the food sector aiming to contribute to the creation of food with unprecedented properties. After an analysis on the temporal evolution of 3D Food Printing (3DFP) in scientific field, a variety of relevant aspects have been studied: the capability of modifying the texture properties of the end products by means of accurate design of the digital models and the printing at high speed that could open for a more practical application at industrial level. Moreover, the studies have focused on two different matrix: cereals based and starchy gels, printing geometric structures (cube, parallelepiped) and design inspired by nature (apple tissue). The thesis is structured in 8 chapters: a brief introduction (chapter 1), objects and outlines of research (chapter 2) and the other sections consists of five published papers in international peer reviewed journals ‘Drawing the scientific landscape of 3D Food Printing. Maps and interpretation of the global information in the first 13 years of detailed experiments, from 2007 to 2020’(chapter 3); ‘Rheological properties, dispensing force and printing fidelity of starchy-gels modulated by concentration, temperature and resting time’ (chapter 4). The chapters 5 and 6 has been dedicated to the creation of 3D-printed food with desired and programmable mechanical properties: ‘Programmable texture properties of cereal-based snack mediated by 3D printing technology’ (chapter 5), ‘Extending 3D food printing application. Apple tissues microstructure as CAD model to create innovative cereal-based snacks’ (chapter 6). Chapter 7 focused on speed up of 3DFP: ‘Extending the 3D food printing tests at high speed. Material deposition and effect of non-printing movements on the final quality of printed structures’. Finally chapter 8 contains the conclusions and some general discussion of the thesis.

Se ha desarrollado un sistema innovador de cocción de alimentos basado en el calentamiento por radiación infrarroja (IR) mediante un láser de CO2 (IR Láser CO2) teniendo en cuenta que el agua posee una elevada capacidad de absorción electromagnética en la longitud de onda del IR Láser CO2. El sistema de cocción se ha adaptado en una impresora 3D de alimentos y se ha diseñado con los siguientes requerimientos: 1) cocción en un área delimitada; 2) capacidad de control de la temperatura de cocción; 3) las dimensiones físicas de la lámpara de CO2 deben adaptarse a la impresora 3D de alimentos; 4) el consumo de energía debe ser compatible con la capacidad de la impresora 3D de alimentos; 5) el sistema debe ser controlado por software; 6) versatilidad para cocinar mientras se imprime el alimento o después de la impresión. En el presente estudio se han usado dos sistemas de cocción por IR Láser CO2. Primero se usó una grabadora y cortadora con IR Láser CO2 en la que se establecieron unas condiciones específicas que permitieron la cocción de hamburguesas de ternera, puré de patatas y masas de pizza. Después se desarrolló un nuevo sistema de cocción integrado en la impresora 3D de alimentos formado por una lámpara láser de CO2, un sistema de galvos para dirigir el haz láser a la zona de cocción y un software que permitía controlar la posición y frecuencia del movimiento de los galvanómetros. Con este nuevo sistema se podía cocinar de manera homogénea un área determinada, debido al rápido movimiento de los espejos de los galvos. Se cocinaron los siguientes alimentos en el interior de la impresora 3D de alimentos: hamburguesas de carne de ternera; preparados vegetales tipo hamburguesas formuladas con legumbres, hortalizas y huevo como ingredientes principales; y bases de pizza. Para demostrar que la cocción fue adecuada y suficiente, la cocción mediante IR Láser CO2 se comparó con diferentes sistemas de cocción tradicionales (plancha, barbacoa y hornos IR, de convección, de suela refractaria y microondas) y se evaluaron las características microbiológicas, físico-químicas y sensoriales de los alimentos cocidos. Se analizó la formación de hidrocarburos aromáticos policíclicos con el fin de evaluar la seguridad toxicológica, y se estudió el efecto térmico en la eliminación de Salmonella Typhimurium, Salmonella Senftenberg y Escherichia coli O157:H7 inoculadas en las hamburguesas de ternera y en los preparados vegetales. Los análisis microbiológicos y toxicológicos demostraron que los alimentos cocinados con el nuevo sistema IR Láser CO2 son tan seguros como los cocinados con los métodos convencionales. Los análisis sensoriales indicaron que la preferencia de los consumidores 12 por los alimentos cocidos con IR Láser CO2 fue igual o superior a la preferencia por los alimentos cocidos con los sistemas convencionales. Además, se desarrolló un modelo numérico basado en la dinámica computacional de fluidos para simular el proceso de cocción de las hamburguesas de ternera y los preparados vegetales y se validó con los resultados experimentales de aumento de temperatura durante el proceso de cocción. Los resultados numéricos de la evolución de la temperatura coincidieron con los datos experimentales, excepto durante los primeros minutos de la cocción. El modelo de simulación numérico se considera una potente herramienta para optimizar el proceso de cocción del sistema IR Láser CO2. A partir de los resultados obtenidos se abren nuevas vías de trabajo, que incluyen estudios de cocción con alimentos de composición sensiblemente diferente a los probados hasta el momento; la simulación del proceso de cocción con diferentes parámetros y estrategias de cocción; y la realización de estudios nutricionales.
An innovative cooking system based on infrared radiation (IR) using a CO2 laser (CO2 IR Laser) has been developed considering that water absorbance of electromagnetic infrared radiation at CO2 laser wavelength is very high. The new cooking system has been adapted into a 3D food printer and has been designed with the following requirements: 1) ability to cook in a delimited area; 2) control of the cooking temperature; 3) physical dimensions that fit inside the 3D Food Printer; 4) energy consumption below the power supply limits; 5) software-controlled system; 6) versatility to cook while printing the food or to cook once the food is printed. In the present study, two CO2 IR Laser cooking systems have been used and tested. The first CO2 IR Laser cooking system studied was a laser engraver and cutter equipment in which specific conditions were applied to cook beef burgers, mashed potatoes bites and pizza dough. After, a new cooking system adapted to the 3D food printer was developed, consisting of a CO2 laser lamp, a system of galvo mirrors that direct the laser beam to the cooking area, and a software that allowed controlling the position and the frequency of movement of galvanometers. With this new system, a chosen area could be homogenously cooked, due to the rapid movement of the galvo mirrors. The food products cooked inside the 3D food printer were: beef burgers; vegetarian patties prepared with legumes, vegetables and egg as main ingredients; and pizza dough. To demonstrate that cooking had been achieved, food products were cooked with the CO2 IR laser systems and different traditional cooking systems (flat and barbeque grills; IR, convection, desk and microwave ovens). Microbiological, physico-chemical and sensory characteristics of the cooked foods were evaluated. The formation of polycyclic aromatic hydrocarbons was analyzed in beef burgers and pizzas to evaluate toxicological safety, and the thermal effect in the count reduction or survival of Salmonella Typhimurium, Salmonella Senftenberg and Escherichia coli O157:H7 inoculated in beef burgers and vegetarian patties was studied. Microbiological and toxicological analyses showed that food products cooked with the new CO2 IR Laser system were as safe as food cooked with traditional methods. Sensory analyses showed that consumers had the same, or even higher, level of preference for foods cooked with CO2 IR laser system in comparison with foods cooked with traditional methods. In addition, a numerical model based on computational fluid dynamics was developed to simulate the cooking process of beef burgers and vegetarian patties, and it was validated with experimental data of temperature evolution during the cooking process. The numerical results for temperature evolution given by the model coincide with the experimental data, except for the first minutes of cooking. The numerical simulation model is a powerful tool to optimize the cooking process of the CO2 IR Laser system. Based on the results obtained, future work will be carried out including cooking experimental studies with foods containing a significantly different composition; the simulation of the cooking process with different parametric conditions; and nutritional studies.

3D food printing is a precise digitalized process that is based on monitoring the characteristics of the printed substrate in accordance with the process parameters. In this thesis mashed potatoes were first mixed with different food additives (agar, alginate, lecithin and glycerol) at different concentrations (0.5, 1 and 1.5%) in order to compare how each additive would affect the yield stress, viscosity, thixotropy, mechanical properties as well as the internal microstructure of potato puree. It was observed that agar and alginate enhanced the rheological and mechanical properties of puree by forming a stronger internetwork structure thus providing better printing with many build up shapes and that are stable post deposition. On the other hand, lecithin and glycerol decreases the rheological and mechanical properties of puree and thus although the extrusion was smooth, end printed products were unstable and collapsed instantly. Additionally, to inspect the reason behind obtaining those rheological and mechanical values a further investigation at the molecular level (applying FTIR and XRD) was done. It was revealed that additives such as glycerol and lecithin can penetrate the starch granules and induce a more intense effect on the structure as their respective concentrations increase by either suppressing (ex, glycerol) or enhancing (ex lecithin) the starch structure. In contrast, long polymeric molecules such as agar and alginate interact partially via the surface of the starch granules modifying partially the conformation of starch structure, which confirms the previous deductions from the rheological properties part. Furthermore, FTIR spectra showed that the skeleton formed by the amylose/amylopectin is somehow hidden in the dehydrated potato flakes, but was covered almost completely upon the addition of water such as to complement that of an original raw potato FTIR spectra, proving that water molecules have a central role in the maintenance of the starch structure conformation. To verify this hypothesis, task 4 was developed in order to make sure after what time of water reduction is the starch conformation altered (using this time potato tubers) and to identify whether the starch structure is modified more by the effect of the water removal or the heat treatment (microwaved and boiling). Findings showed that microwaved (MP) and boiled (BP) potato were more susceptible for water evaporation by freeze drying expressed via the following microstructural changes only after 6 hours of lyophilization; 1- obtaining an IR spectrum with much lower intensities (dried spectrum) compared to the initial spectrum, 2- undergoing a major transformation from gelatinized swollen starch to some recoiling towards a dried starch granule (SEM figures), 3- exhibiting an increase in the intensity of their respective XRD patterns. Moreover, RP took around 24 hours to reach a dried stage that was characterized by some ruptured granules embedded within leached starch matrix, an FTIR spectra that resembles in intensity that of BP and MP, possessing two peaks at 485 cm-1 and 620 cm-1 and that were assigned as a distinctive for a dried potato starch spectrum. Concluding that water removal sublimes the effect of the heat processing treatment, being the major contributor in the modifications of the starch structure. MP and BP were then used as basic samples for 3D printing trials while adding to each different food substrates at 1% concentration with respect to the weight (butter, olive oil, alginate and agar) except for carrots which were added at a ratio of 1/3 of the respective potato weight. All MP samples showed higher rheological and mechanical properties that lead to more stable printed products. Best printability was accounted with butter insertion which elevated the yield stress and thixotropy, thus increasing structural integrity and maintaining higher retaining shape property while preserving smooth extrusion and creamy surface structure.
La impresión 3D de alimentos es un proceso digitalizado preciso que se basa en el monitoreo de las características del sustrato impreso de acuerdo con los parámetros del proceso. En esta tesis, se ha utilizado como substrato el puré de patatas mezclado con diferentes aditivos alimentarios (agar, alginato, lecitina y glicerol) a diferentes concentraciones (0,5, 1 y 1,5%) para poder comparar el efecto de cada aditivo sobre las propiedades reologicas (límite elástico, viscosidad, tixotropía), mecánicas y la microestructura interna del puré de patata. Los resultados han permitido observar que el agar y el alginato mejoraron las propiedades reológicas y mecánicas del puré al formar una estructura de interconexión más fuerte, proporcionando una mejor impresión con diversidad de formas y estables después de la deposición. Por otro lado, el uso de lecitina y glicerol disminuyeron las propiedades reológicas y mecánicas del puré y, por lo tanto, aunque la extrusión fue posible, los productos finales impresos fueron inestables y se colapsaron al instante. Adicionalmente, para validar la obtención de esos valores reológicos y mecánicos, se realizó una investigación adicional a nivel molecular aplicando FTIR y XRD. Los resultados indicaron que los aditivos glicerol y lecitina pueden penetrar en los gránulos de almidón e inducir un efecto más intenso sobre la estructura a medida que aumentan la concentración, suprimiendo (glicerol) o potenciando (lecitina) la estructura del almidón. Por el contrario, moléculas poliméricas largas como agar y alginato interactúan parcialmente a través de la superficie de los gránulos de almidón modificando parcialmente la conformación de su estructura, lo que confirmó los resultados previos de las propiedades reológicas. Además, los espectros FTIR mostraron que el esqueleto formado por la amilosa / amilopectina que esta " oculto" en las escamas de patata deshidratada, con la adición de agua vuelve a tener prácticamente el espectro original de FTIR de la patata cruda, lo que demuestra que las moléculas de agua tienen un papel central en el mantenimiento de la conformación de la estructura del almidón. Para verificar la hipótesis, de que " la reducción del agua puede alterar la conformación y estructura del almidón del tubérculo de patata" se procedió a comprobar el efecto de la eliminación de agua (liofilización) o el efecto del tratamiento térmico (cocción en microondas o hervido). Los resultados mostraron que la evaporación del agua por liofilización presentaba cambios micro-estructurales superiores a las cocinadas en microondas (MP) o hervida (BP) ya que con solo 6 horas de liofilización se obtuvo; un espectro FTIR con intensidades mucho más bajas (espectro seco) en comparación con el espectro inicial; se observó mediante SEM una transformación importante del almidón hinchado (gelatinizado) hacia un gránulo de almidón seco y se incrementó la intensidad de sus respectivos patrones de X-RD. Además, en la patata cruda (RP) se tardó alrededor de 24 horas en alcanzar la deshidratación, que se caracterizó por algunos gránulos rotos incrustados dentro de la matriz del almidón lixiviado, un espectro FTIR que se asemeja en intensidad al de BP y MP, (picos a 485 cm-1 y 620 cm-1) que fueron asignados como un distintivo para un espectro de almidón de patata deshidratada. Concluyendo que la eliminación del agua por sublimación produce efectos micro-estructurales superiores al del procesamiento térmico, siendo el agua el principal contribuyente de las modificaciones de la estructura del almidón. Para finalizar, se usaron estos dos tratamientos: cocción al microondas (MP) y hervido (BP) para las pruebas de impresión 3D. Los resultados obtenidos indicaron que todas las muestras MP mostraron mejores propiedades reológicas y mecánicas lo que nos permitió obtener productos impresos más estables

Gli insetti edibili sono stati riconosciuti come una fonte sostenibile di proteine animali di elevato valore biologico ed in grado di fornire un importante contributo per la crescente domanda di prodotti di origine animale. Ad oggi si contano circa 1900 specie di insetti edibili consumati da oltre 2 miliardi di persone che vivono soprattutto in Asia, Africa e Sud America. Nonostante ciò, laddove il consumo di insetti non fa parte della cultura delle popolazioni, come in Europa e Nord America, la percezione negativa dei consumatori è stata identificata come l’ostacolo più importante per la loro adozione. Le strategie attualmente in atto per superare l’ostacolo del disgusto comprendono la promozione razionale supportata da argomenti etici e nutrizionali, l’identificazione di tratti psicologici, e lo sviluppo di prodotti alimentari con buone proprietà sensoriali. Nello specifico, recenti ricerche hanno riscontrato che il consumo di insetti in società occidentali può essere favorito se ne è ridotta la loro visibilità e se questi sono introdotti in prodotti familiari. Pertanto, lo scopo della presente tesi è di creare conoscenza necessaria a supportare l’introduzione di insetti nella dieta occidentale attraverso l’impiego di tecnologie di trasformazione di alimenti convenzionali e innovative. A tale scopo, la trasformazione di insetti quali le larve di tarme della farina (Tenebrio molitor) in una polvere secca impiegabile per formulazioni di snack può essere considerata come una valida opportunità. Inizialmente sono stati studiati gli effetti di alcuni processi su attributi tecnologici e qualità nutrizionale delle larve, fornendo informazioni necessarie per l’ottenimento di una polvere di insetto secca e stabile, impiegabile in preparazioni alimentari. Una scottatura in acqua delle larve ne ha permesso l’ottenimento di un semilavorato di colore stabile e adatto all’essiccazione. Lo studio delle proprietà igroscopiche delle larve secche in polvere ne ha evidenziato un comportamento di isoterma di tipo II, tipico di alimenti ricchi in proteine, e ne ha permesso la stima della loro stabilità a valori di umidità del 5% su base secca. Successivamente, in previsione di un utilizzo immediato, la polvere di larve è stata impiegata per la realizzazione di snack estrusi a base di cereali. Le variabili di processo e la formulazione hanno influito largamente sulle proprietà del prodotto finito, tra cui microstruttura, proprietà meccaniche e nutrizionali. L’adozione di alte temperature di processo e alte velocità delle viti per l’estrusione formulati al 10% di polvere di insetto e 90% di farina di grano tenero ha permesso l’ottenimento di snack con buone proprietà meccaniche. In quest’ultimo caso, l’aggiunta di polvere di larve di tarme della farina e ha aumentato il contenuto in proteine del 35%, contenuto sufficiente considerare lo snack “fonte di proteine” secondo la corrente legislazione europea. Inoltre, gli sforzi di taglio del trattamento di estrusione hanno aumentato la digeribilità delle proteine delle larve, ed è stata identificata una forte correlazione tra la microstruttura degli snack e le loro proprietà meccaniche e di digeribilità, aprendo nuovi orizzonti per la realizzazione di alimenti con specifiche proprietà dettate dalla loro microstruttura. Il quarto capitolo del presente elaborato è stato dedicato all’esplorazione della stampa 3D come tecnologia per la realizzazione di alimenti con geometrie innovative a base di farine di cereali. Nello specifico sono stati studiati gli effetti di alcune variabili di stampa e design degli oggetti da realizzare sulla performance di stampa, microstruttura e proprietà meccaniche degli snack. La tecnologia impiegata, basata sulla modellazione per deposizione di materiali fluido-densi, si è dimostrata adatta alla riproduzione delle geometrie esterne ed interne degli snack, caratteristiche successivamente correlate alle loro proprietà meccaniche. Infine, le polveri di larve sono state sostituite in quantità crescenti a impasti di farina di grano tenero, migliorandone significativamente il profilo amminoacidico e validando la promozione di insetti basata su attributi nutrizionali.
Edible insects have been recognized as a sustainable source of high-value animal especially proteins, bearing the potential to help satisfying the raising demand of meat products. Globally, over 1900 species of insects are part of the diet of about 2 billion people in Asia, Africa and South America. Yet, in parts of the world where their consumption is not traditional, such as Europe and North America, consumer negative perception is identified as a significant barrier to their widespread adoption. Strategies to overcome the disgust of Western consumers focus on rational promotion through ethical and nutritional arguments, identification of psychological individual traits, the development of sensory appealing and appropriate food products. For the latter, recent research revealed that presenting insects invisibly into familiar food carriers favours their acceptability by Western consumers. Therefore, this thesis aims at building knowledge for supporting the introduction of insects in Western diet by means of conventional and innovative food processing technologies. Herewith, the conversion of insects such as Yellow mealworms (Tenebrio molitor) in a dry and ground form and its use in snack foods has been identified as a major opportunity to this end. The first step towards understanding how pre-treatments affect technological and nutritional attributes of larvae of Y. mealworms are initially explored, delivering essential knowledge for obtaining a dry and stable insect powder necessary for any industrial application. Blanching of larvae of Yellow mealworms allowed to obtain a semi-finished product stable in colour and suitable for drying. Dry larvae of Yellow mealworms presented a type II sorption isotherm, typical of hygroscopic foods high protein food, which allowed to estimate a product stability at 5% moisture (d.b.). Successively, the potential of Y. mealworms as a valuable source of protein in extruded cereal snacks was investigated to support their immediate industrial use. Herewith, processing variables and formulation were proved to play a major role in quality attributes of end products, including microstructure, texture and nutritional characteristics. When wheat flour was substituted by 10% of ground Y. mealworm, protein content increased by 35%, and provided more than 16% energy of the formulation, enough to claim the snack as “source of protein” according to current European food law. Besides, a strong relationship between the microstructure and mechanical and nutrient digestibility (starch and protein) was identified, and high shear forces in extrusion cooking improved the digestibility of larvae protein. As a result, this outcome is expected to open horizons in designing innovative food microstructures with tailored mechanical and nutritional characteristics. The fourth chapter of this thesis explored 3D printing as a technology to develop a computer controlled foods with innovative shapes. In summary, the combined effect of printing variables and internal shape design are investigated by following the printing performance, microstructure and mechanical properties of such snacks. Cylindrical objects of specific dimensions and different degree of porosity were designed and realized by depositing a wheatbased dough through a fused deposition modelling printer. As a result, this technology showed high accuracy in reproducing external and internal morphological features of snacks, which were ultimately correlated to mechanical features. Successively, the 3D printing was further adopted to develop a cereal snack containing ground larvae of Y. mealworms. In this study, the effects of formulation and processing conditions on microstructure, nutritional profile and quality attributes of snacks were investigated. A significant improvement of the amino acid profile of wheat flour was observed when snacks were enriched with different levels of ground larvae, validating the rational promotion of insects based on nutritional arguments.

Ce travail de thèse s'inscrit dans un contexte démographique mondial en évolution. En effet, des solutions nutritionnelles sont à développer pour pallier au vieillissement de la population, dont une conséquence est le nombre croissant de personnes présentant des déficiences masticatoires. La texturation d'aliments, riches en protéines de bonne qualité nutritionnelle, est un point essentiel pour une bonne mastication et pour une assimilation optimale des nutriments, mais également pour l'acte et le plaisir de manger.L'impression 3D alimentaire est une des voies de recherche possibles pour concevoir de nouveaux aliments fonctionnels à destination des personnes fragiles. Afin de correspondre aux problématiques sociétales actuelles, ces aliments doivent être sains, personnalisés et socialement acceptables. Pour répondre à ce cahier des charges ambitieux, une approche en quatre étapes a été utilisée dans ce travail de thèse :1) Le développement d'une imprimante 3D parfaitement adaptée à la mise en œuvre de matrices carnées. La maîtrise des paramètres d'impression permet désormais de proscrire l'utilisation d'agents de texture et donc, de concevoir des aliments dont la formulation est plus simple et plus naturelle ;2) Afin de potentialiser la structure des aliments imprimés et d'élargir la gamme des textures possibles, la réaction de glycation a été étudiée et appliquée à un milieu modèle à base de gélatine. Cette matière première a révélé toute sa complexité lors de la mise en œuvre de la réaction, nécessitant une étude d'élucidation des mécanismes mis en jeu. Ainsi, il a été montré que la teneur en eau initiale et l'indice Bloom de la gélatine, en influençant de façon notable la structure secondaire de la gélatine, conditionnaient fortement le devenir de la réaction de glycation ;3) Les personnes présentant une déficience masticatoire peuvent également souffrir d'un déficit de salivation. Cette troisième partie du travail de thèse a donc consisté à étudier les propriétés rhéologiques de matrices riches en protéines animales, mais aussi la façon d'incorporer un substitut salivaire naturel directement dans l'aliment pour optimiser les propriétés d'extrusion des matrices. Cet aliment fonctionnel, à base de protéines et de mucilage de graines de lin, permettra de lubrifier la cavité buccale et donc, de réduire les douleurs et les risques de fausses routes lors de la mastication et de l'ingestion par des personnes souffrant de xérostomie, d'hyposialie et de dysphagie ;4) Le couplage de la conception d'un nouvel aliment fonctionnel et d'un procédé de rupture tel que l'impression 3D peut engendrer un phénomène de néophobie, voire de rejet, de la part des consommateurs. La quatrième partie de ce travail s'est attachée à initier une approche sociologique visant à évaluer l'acceptabilité sociale de ce nouveau procédé, sur la base de nouvelles collaborations entre les Sciences du Vivant et les Sciences Humaines & Sociales.Les prochains travaux vont consister déterminer le mode de post-traitement le plus adapté au respect des propriétés de l'aliment, à en caractériser les propriétés nutritionnelles et, à définir et à appliquer les méthodes nécessaires pour assurer les qualités sanitaires et organoleptiques des aliments fonctionnels
This thesis is part of a rapidly changing of worldwide demographic context. Indeed, nutritional solutions need to be developed to offset the ageing of the population, one of the consequences of which is the growing number of people with masticatory deficiencies. The texturing of foods, rich in proteins of good nutritional quality, is essential for good mastication and optimal assimilation of nutrients, but also for the act and pleasure of eating.3D food printing is one of the possible research ways for designing new functional foods for frail people. To meet current societal challenges, these foods need to be healthy, personalized and socially acceptable. To meet these ambitious specifications, a four-stage approach was used in this thesis work:1) The development of a 3D printer perfectly suited to the use of meat matrices. By controlling the printing parameters, we can now avoid the use of texturizing agents, enabling us to design foods with simpler and more natural formulations;2) In order to potentiate the structure of printed foods and extend the range of possible textures, the glycation reaction was studied and applied to a gelatin-based model medium. This raw material revealed all its complexity when the reaction was implemented, necessitating a study to elucidate the mechanisms involved. It was shown that the initial water content and Bloom index of the gelatin, by significantly influencing the secondary structure of the gelatin, strongly conditioned the fate of the glycation reaction;3) People with masticatory deficiencies may also suffer from salivary deficiencies. This third part of the thesis therefore involved studying the rheological properties of matrices rich in animal proteins, as well as how to incorporate a natural saliva substitute directly into the food in order to optimize the extrusion properties of the matrices. This functional food, based on flax protein and mucilage, will lubricate the oral cavity, reducing pain and the risk of wrong way during chewing and swallowing in people suffering from xerostomia, hyposialia and dysphagia;4) Coupling the design of a new functional food with a disruptive process such as 3D printing can lead to neophobia, or even rejection, on the part of consumers. The fourth part of this work aims to initiate a sociological approach designed to assess the social acceptability of this new process, drawing on new collaborations between the Life Sciences and the Human and Social Sciences.Future work will focus on determining the post-processing method best suited to respecting the food's properties, characterizing its nutritional properties, and defining and applying the methods needed to guarantee the sanitary and organoleptic qualities of functional foods

[ES] Las microalgas son organismos unicelulares fotosintéticos microscópicos que se encuentran en gran variedad de ambientes y son muy eficientes en la transformación de energía solar en biomasa. Los estudios realizados hasta el momento hacen referencia a posibles beneficios de la incorporación de microalgas en la dieta, por la mejora del sistema cardiovascular, las propiedades adelgazantes y energizantes, capacidad antioxidante, o la reducción del colesterol y los triglicéridos. La forma más habitual de consumir las microalgas es como suplemento dietético en forma de tabletas, cápsulas o polvo. La incorporación de biomasa de microalgas en productos tradicionales se ha enfrentado al reto de la aparición de colores verdes fuertes, así como su consistencia pulverulenta que puede afectar la textura y percepción del producto. Todos estos aspectos constituyen las principales áreas de mejora para conseguir un mayor grado de aceptación de productos con microalgas, y son la base del reto de este proyecto. El objetivo de la presente tesis doctoral fue el desarrollo de nuevos productos alimentarios incorporando las propiedades nutricionales de la biomasa de microalgas, incrementando o mejorando con ello, las propiedades nutricionales del alimento original. Para conseguir este objetivo se evaluaron a nivel fisicoquímico, reológico y textural, la incorporación de diferentes especies de microalgas (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina y Nannochloropsis gaditana) en distintas matrices alimentarias (productos horneados, emulsiones y extrusionados). Por otra parte, se evaluó y caracterizó la incorporación de las microalgas utilizando diferentes tecnologías como la impresión 3D o la extrusión. Además de cómo afecta la incorporación de las microalgas a los productos obtenidos, se evaluaron los aspectos nutricionales de su incorporación, en cuanto al aporte de minerales y su biodisponibilidad. Las propiedades reológicas de las masas y emulsiones enriquecidas con microalgas (Spirulina, Chlorella y Dunaliella) indicaron que su comportamiento viscoelástico fue modificado y mejorado, mostrando características aptas para este tipo de productos. La adición de microalgas (Spirulina y Chlorella) a las masas utilizadas para la impresión 3D de galletas y snacks, permitió una mejor extrusión o impresión de éstas, obteniendo muestras impresas en 3D de forma cilíndrica, más precisas en cuanto a sus dimensiones con respecto a la estructura cilíndrica diseñada. Además, las muestras impresas presentaron mayor estabilidad y resistencia, antes y después del proceso de horneado comparadas con la muestra control. Para los productos horneados, tanto para las rosquilletas como los snacks impresos en 3D, la adición de microalgas (Spirulina y Chlorella) permitió mayor estabilidad en términos de textura. Ligeros cambios en los parámetros fisicoquímicos y de expansión se produjeron por la adición de Spirulina y Chlorella en los productos extrusionados. Además, los extrusionados enriquecidos con Nannochloropsis, mostraron parámetros similares a los de la muestra de control. Todos los productos presentaron colores luminosos y apariencias innovadoras y atractivas. En cuanto a los minerales, se observó un aumento de P, K, Ca, Na, Mg, Fe y Se con la adición de Spirulina y Chlorella, junto con el aumento de la concentración adicionada de microalgas. Siguiendo la normativa sobre etiquetado nutricional de los alimentos, el enriquecimiento con microalgas en rosquilletas se puede clasificar como un alimento "rico en hierro (Fe)". De igual forma, las rosquilletas y galletas enriquecidas con microalgas pueden considerarse un alimento "alto en selenio (Se)". Además, la incorporación de Spirulina y Chlorella en las formulaciones de galletas, permitió una mayor bioaccesibilidad del contenido de P, K, Ca, Mg, Fe, Zn y Se para la absorción en el cuerpo comparado con las muestras control.
[CAT] Les microalgues són organismes unicellulars fotosintètics microscòpics. Són molt eficients a l'hora de transformar l'energia solar en biomassa. Els estudis realitzats fins ara fan referència a possibles beneficis de la incorporació de microalgues en la dieta per produir una millora del sistema cardiovascular, per presentar propietats per aprimar i donar energia, per mostrar capacitat antioxidant o per afavorir una reducció del colesterol i els triglicèrids. La forma més habitual de consumir microalgues és com a suplement dietètic en forma de tauleta, càpsula o en pols. La incorporació de biomassa de microalgues en productes tradicionals s'ha afrontat al repte de l'aparició d'un color verd fosc i d'una consistència polsosa que pot afectar a la textura i, per tant, a la percepció del producte. Aquests aspectes constituïxen les principals àrees de millora per aconseguir un major grau d'acceptació de productes amb microalgues i són la base del repte d'aquest projecte. L'objectiu d'aquesta tesi doctoral és el desenvolupament de nous productes alimentaris que incorporen les propietats nutricionals de la biomassa de microalgues, de manera que s'incrementen o es milloren les propietats nutricionals de l'aliment original. Per aconseguir aquest objectiu s'avaluaren a escala fisicoquímica, reològica i de textura la incorporació de diferents espècies de microalgues (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina i Nannochloropsis gaditana) en diferents matrius alimentàries (productes fornejats, emulsions i extrudits). D'altra banda, s'avaluà i caracteritzà la incorporació de les microalgues utilitzant diferents tecnologies com la impressió en 3D o l'extrusió. A banda de valorar com afecta la incorporació de microalgues als productes elaborats, s'avaluaren els aspectes nutricionals, pel que fa a l'aportació i biodisponibilitat de minerals. Les propietats reològiques de les masses i emulsions enriquides amb microalgues (Spirulina, Chlorella i Dunaliella) indicaren que el seu comportament viscoelàstic fou modificat i millorat, de tal manera que mostrà característiques aptes per aquest tipus de productes. L'addició de microalgues (Spirulina i Chlorella) en les masses utilitzades per a la impressió 3D de galetes i snacks permeté una millor impressió, ja que s'obtingueren mostres impreses de forma cilíndrica amb unes dimensions més precises respecte a l'estructura cilíndrica dissenyada. A més, les mostres impreses presentaren una major estabilitat i resistència abans i després del procés de fornejat en comparació amb la mostra control. Respecte als productes fornejats, l'addició de microalgues (Spirulina i Chlorella) a les rosquilletes i els snacks impresos en 3D permeté una major estabilitat en termes de textura. Lleugers canvis als paràmetres fisicoquímics i d'expansió es produïren per l'addició d'Spirulina i Chlorella en els productes extrudits. A més, els extrudits que foren enriquits amb Nannochloropsis mostraren paràmetres similars als de la mostra control. Tots els productes presentaren colors lluminosos i aparences innovadores i atractives. Pel que fa als minerals, s'observà un augment de P, K, Ca, Na, Mg, Fe i Se quan s'afegí Spirulina i Chlorella, directament relacionat amb l'augment de la concentració de microalgues. Seguint la normativa sobre etiquetatge nutricional dels aliments, l'enriquiment amb microalgues en rosquilletes ens permet classificar-les com a aliment "ric en ferro (Fe)". De la mateixa manera, les rosquilletes i galetes enriquides amb microalgues poden considerar-se un aliment "alt en seleni (Se)". A més a més, la incorporació de Spirulina i Chlorella en les formulacions de galetes, permeté una major bioaccessibiltat del contingut de P, K, Ca, Mg, Fe, Zn i Se comparat amb les mostres control.
[EN] Microalgae are microscopic unicellular and photosynthetic organisms that can be found in a wide variety of environments. These microorganisms are very efficient when transforming solar energy into biomass, due to their cellular structure, which is completely submerged in an aqueous medium, forming an adequate surface for the exchange of nutrients and gases. Microalgae compounds are now known to exhibit cardioprotective, immunomodulatory, anti-proliferative, anti-inflammatory, cognitive, neurobehavioral and antimicrobial properties, amongst others. Researchers have shown possible benefits of the incorporation of microalgae in the diet so far. The most common way to consume microalgae is as a dietary supplement in the form of tablets, capsules or powder. The incorporation of microalgae biomass in traditional products has faced the challenge of the appearance of strong green colours, as well as its powdery consistency that can affect the texture and perception of the product. All these aspects constitute the main areas for improvement the development of microalgae-based products, and they are the challenges faced of this project. The main objective of this PhD Thesis was the development of novel food products incorporating the nutritional properties of microalgae biomass, thereby increasing or improving the nutritional properties of the original food matrix. To achieve this goal, the effect of the addition of different species of microalgae (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina and Nannochloropsis gaditana) on the physicochemical, rheological and textural properties of different food matrices (baked products, emulsions and extrudates) was evaluated. Furthermore, the effect of the incorporation of microalgae using different technologies such as 3D printing or extrusion to obtain food products was studied. In addition, how the incorporation of microalgae affects the nutritional aspects of the food products in terms of the contribution of minerals and their bioavailability was also evaluated. The rheological properties of doughs, batters and emulsions enriched with microalgae (Spirulina, Chlorella and Dunaliella) indicated that their viscoelastic behaviour was modified and improved, showing characteristics suitable for this type of products. The addition of microalgae (Spirulina and Chlorella) to the doughs and batters used for the 3D printing of cookies and snacks, allowed a better extrusion or printing behaviour. This allowed obtaining cylindrical 3D printed samples, more precise in terms of their dimensions with respect to the designed cylindrical structure. In addition, the 3D microalgae-printed sample structures presented greater stability and resistance, before and after the baking process compared to the control sample. For baked products, both for breadsticks and 3D printed snacks, the addition of microalgae (Spirulina and Chlorella) allowed greater stability in terms of texture. Slight changes in the physicochemical and expansion parameters were produced by the addition of Spirulina and Chlorella in the extruded products. In addition, the extrudates enriched with Nannochloropsis, showed similar parameters to those of the control sample. Microalgae-enriched obtained products showed bright colours with appealing appearances. Regarding minerals, an increase in P, K, Ca, Na, Mg, Fe and Se was observed with the addition of Spirulina and Chlorella, along the increase of concentration of microalgae addition. Following the regulations on nutrition labelling for food stuffs, breadstick enrichment with microalgae are a food "high in iron (Fe)" In the same way, breadsticks and cookies enriched with microalgae can be considered a "high in selenium (Se)" food. Going a step further, Spirulina and Chlorella vulgaris incorporation in cookie formulations allowed for greater bioaccessibility of P, K, Ca, Mg, Fe, Zn, and Se content for absorption in the body than control cookies.
Uribe Wandurraga, ZN. (2020). Microalgae as novel ingredients for the formulation of food products [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158743
TESIS

Synthetic, self-oscillating vocal fold (VF) models are physical models whose life-like vibration is induced and perpetuated by fluid flow. Self-oscillating VF models, which are often fabricated life-size from soft silicone elastomers, are used to study various aspects of voice biomechanics. Despite their many advantages, the development and use of self-oscillating VF models is limited by the casting process used to fabricate the models. Consequently, this thesis focuses on the development of 3D printing processes for fabricating silicone VF models. A literature review is first presented which describes three types of material extrusion 3D printing processes for silicone elastomers, namely direct ink writing (DIW), embedded 3D printing, and removable-embedded 3D printing. The review describes each process and provides recent examples from literature that show how each has been implemented to create silicone prints. An embedded 3D printing process is presented wherein a set of multi-layer VF models are fabricated by extruding silicone ink within a VF-shaped reservoir filled with a curable silicone support matrix. The printed models successfully vibrated during testing, but lacked several desirable characteristics which were present in equivalent cast models. The advantages and disadvantages of using this fabrication process are explored. A removable-embedded 3D printing process is presented wherein shapes were fabricated by extruding silicone ink within a locally-curable support matrix then curing the silicone ink and proximate matrix. The printing process was used to fabricate several geometries from a variety of silicone inks. Tensile test results show that printed models exhibit relatively high failure strains and a nearly isotropic elastic modulus in directions perpendicular and parallel to the printed layers. A set of single-material VF models were printed and subjected to vibration testing. The printed models exhibited favorable vibration characteristics, suggesting the continued use of this printing process for VF model fabrication. A micro-slicing process is presented which is capable of creating gcode for 3D printing multiple materials in discrete and mixed ratios by utilizing a previously-sliced single-material shape and a material definition. An important advantage of micro-slicing is its ability to create gcode with a mixed-material gradient. Initial test results and observations are included. This micro-slicing process could be used in material extrusion 3D printing

Vocal fold models are valuable for studying voice production. They provide an alternative method of studying the mechanics of the voice that does not require in vivo experimentation or the use of excised human or animal tissue. In this thesis, a new method of creating vocal fold models through additive manufacturing is described. The purpose of this research was to reduce model fabrication time, to decrease the number of model failures during manufacturing, and to lay the foundation for creating models with more lifelike geometric and material properties. This research was conducted in four stages. First, a suitable silicone additive manufacturing technique using a UV-curable silicone was chosen. The technique chosen was called freeform reversible embedding (FRE) and involved embedding liquid silicone material into a gel-like medium named organogel. The UV-curable silicone's material properties were identified to confirm its utility in vocal fold model design. Second, an open-source, fused deposition modeling slicing software was selected to create g-code for the printer. Applicable software settings were tuned through qualitative printing tests to find their optimal values for use in FRE printing. Third, 3D-printed cubes were used in tensile tests to characterize the material properties of FRE-printed, silicone material. The cubes were found to be anisotropic, exhibiting different modulus values corresponding to the layer orientation of the printed material. Fourth, vocal fold models were FRE-printed in two different layer orientations and were used in phonation tests to gather data for onset pressure, vibratory frequency, amplitude, and flow rate. The printed models self-oscillated and withstood the strains induced by phonation. These tests showed that layer direction affects the phonation properties of the models, demonstrating that models with layers in the coronal plane had slightly lower frequencies and onset pressures than models with layers in the sagittal plane. The models' onset pressures were higher than what is found in human vocal folds. However, their frequencies were within a comparable range. These tests showed the effectiveness of additive manufacturing in the application of vocal fold fabrication, reducing production effort by allowing researchers to go directly from model design to fabrication in a single manufacturing step. It is anticipated that this method will be modified to incorporate printing of multiple stiffnesses of silicone to better mimic the material properties of vocal fold tissue, and that the anisotropy of 3D-printed material will be leveraged to model the anisotropy of human vocal folds. This work also has potential application areas outside of voice research.

Children with Charcot-Marie-Tooth disease (CMT), are often prescribed custom-made ankle-foot orthoses (AFO) to manage walking difficulty. These externally worn assistive devices are usually handmade using a plaster cast of the patient's lower limb followed by thermoplastic vacuum forming. This traditional approach is labour-intensive and provides limited design options, resulting in AFOs which are cumbersome and associated with low acceptability, discomfort and suboptimal biomechanical function. The aim of this PhD Thesis was to develop, redesign and evaluate 3D printed AFOs compared to traditional handmade AFOs for children with CMT. A systematic literature review revealed that 3D printing AFOs has many potential benefits over traditional methods, including the development of novel designs that optimise stiffness and energy dissipation, improve gait, comfort and fit. The relationship between functional ability in 60 children with CMT and associated gait deviations using 3D gait analysis was assessed. The results showed that not all children with CMT have the typically described foot drop, push-off deficit and ‘steppage gait’ pattern. Instead, three distinct gait patterns exist at the ankle, indicating patient-specific orthotic design pathways. In 12 children with CMT, traditional handmade AFOs, replicated and iteratively redesigned 3D printed AFOs were compared to a shoe only condition using 3D gait analysis, in-shoe pedobarography and a patient satisfaction scale. Replicated 3D printed AFOs were comparable to traditional AFOs for all gait outcomes and patient satisfaction scores. Iteratively redesigned 3D printed AFOs reduced mass by, on average, 35% and improved ankle plantarflexion angle during the push-off phase of gait by up to 7°. The design, gait and acceptability of traditionally handmade AFOs can be replicated and redesigned with 3D printing in children with CMT.

The aim of this study is to investigate night Ankle Foot Orthoses, commonly prescribed to Duchenne Muscular Dystrophy patients to understand if there are margins to increase their comfort, aesthetic customization and psychological acceptance by the users, but even to improve their manufacturing process and to reduce costs. Duchenne is a rare form of muscular dystrophy affecting 1 on 3.500 male children that, at about 8 to 12 years old progressively become wheelchair bounded and with an expectation of life on the late 20 or 30 years old, since usually cardiac or pulmonary complications occur. Due to muscles’ weakening, Achilles tendon takes over on muscle tissue and starts to thicken and shrink, causing plantar flexion and retractions, while the function of AFOs is for applying a stretching force that can delay equine deformation of the feet. It is scientifically demonstrated that a constant use of night Ankle Foot Orthosis, together with physiotherapy, can extend the independent ambulation by up to two years and delay the occurrence of other complications. The PhD study was conducted from 2012 to 2014 thanks to a partnership between the Department of Architecture of Ferrara University and Parent Project Onlus for Duchenne and Becker. Moreover the thesis was endorsed by the Neuropsychiatric Department specialized in Duchenne of the Policlinico Gemelli in Rome, orthoses manufactures, experts in 3D survey, parametric design, and solid prototyping and, last but not least, by the direct contact with final users and their families. The core of the thesis was organized in three parts. In the first one, after a brief recognition on the disease, a market analysis on all the lower limb orthoses available on Italian, European and North American market was conducted. The elaborated interactive database was essential to understand the state of art, the Italian picture and the most advanced innovations and ongoing experimentations. All these data were a crucial tool in the design process. The second part focused on cultural and methodological approaches in the design of the AFO. After an overview on theories that frame the research, as Customer Centered and User Centered Design, as well as Universal Design, Inclusive Design, Design for All and Design for disabilities, a Quality Function Deployment process was chosen to translate theories into design directives. Relating user needs, technical requirements and comparison with the competitors, the scheme provides the guidelines for the design of a really innovative dorsal night AFO for DMD patients. The results of the research and future perspective are exposed in the third part. The analysis of the handcraft current processes of manufacturing suggested the opportunity of investigating the application of modern technologies aimed at the optimization of the process and the final product. Indirect survey techniques of photo-modelling or laser scanner are used to accurately reproduce the shape of the leg, while the user is sitting on a particular bench designed to acquire the foot in a stretching position and to entertain the child as he was on a rocking horse. The 3D virtual reconstruction of the limb, combined with 15 control points, is elaborated in an algorithm of parametric design to obtain a customized AFO that can be 3D printed with complete freedom of personalization to meet the tastes of the child. The results are highly promising and deserve to be further developed in future experimentations on field.

Subject of this diploma thesis is a design of a prosthetic foot for an additive manufacturing. It is a dynamic foot made of plastic, designed for an 80 kg patient with a second level of a movement aktivity. From a few concepts is chosen one, which is then optimalized and printed with a MJF method. Functional sample is then undergoing static and cyclic tests according to ISO 10328.

Teff (Eragrostis tef) is a minor cereal, which has attracting growing interest in the last years because of its high adaptability to harsh environmental conditions. It is consumed as a whole grain so it contains high amount of fibre and bioactive compounds as well as it presents an excellent nutrient profile due to a well-balanced aminoacid composition and high content of various minerals and vitamins. For all these reasons and due to the increasing global interest in healthy foods, teff has the potential to be used in products with improved functional properties. The main aim of this research was to develop the knowledge for affirming the use of such minor cereal, Eragrostis Tef. So, it has been studied starting from its cultivation up to the product development. The specific goals of this research were: · The study of the adaptability of teff and other two minor cereals, sorghum and millet, to a Mediterranean area under deficit irrigation. Yield parameters, nutritional properties and antioxidant capacity were evaluated. · The development of a healthy ready-to-eat cereal breakfast with the extrusion-cooking technology by using teff flour and by varying some extrusion variables, such as temperature of the last barrel zone and feed moisture of the blends. Specifically physical and structural properties, as well as pasting properties and some functional essential attributes (e.g. antioxidant capacity, phenolic content, fibre content) of extruded samples were investigated. · The adoption of an emerging technology, 3D food printing, to obtain innovative and personalized snack, nutritionally designed to meet the specific micronutrient requirements of women. Also in this study teff flour was used in the food formulas. The main results of this research study have permitted some considerations: · Teff appears to be the best-adapted crop, among those studied, to the sub-arid environment of South of Italy due to its best yield stability and nutritional quality also showing a great potential to contribute to food and nutrition security in Mediterranean environments. · The incorporation of teff flour significantly changed the physical and sensory characteristics of extruded cereals. In particular lightness and crispiness were affected by inclusion of teff flour, but process management of extruded cereal breakfast, according to different process conditions, such as feed moisture and temperature of the last barrel, allows creating desirable quality of final products. Moreover, varying the process parameters and increasing teff flour addition, microstructural properties of sample change considerably and these characteristics could affect structural properties of extruded products. · Teff flour served as a good source of polyphenols, which are the major contributors to the antioxidant capacity, in extruded ready-to-eat cereal breakfast. Under optimal conditions, the extrusion-cooking technology is a suitable method for the preparation of gluten-free products with high level of dietary fibre. · Teff flour has been suitable for the 3D printing technology to obtain personalized foods. 3D printed snack met the micronutrient requirements of women, particularly iron, folate and calcium. These minerals/vitamins reached the RDA percentage requested to obtain the nutritional claim for such micronutrient. Moreover 3D printed snack showed a high fibre content so they also contribute to the women’ health condition. Finally such snack were well appreciated by the panelists, assuming that consumers could accept this innovative and personalized products.

The following report presents a Master thesis project about a re-design of an ankle foot orthosis using additive manufacturing as the production method, conducted by a student in Spring 2020 as part of the Master’s programme Industrial Design at Jönköping University’s School of Engineering. Ankle foot orthoses are the most prescribed lower extremity orthoses worldwide and are worn in a visually obtrusive way making patients feel stigmatized for their disability. The social stigma makes it emotionally difficult for many users to wear an AFO frequently enough for proper rehabilitation. Despite its significance and wide spread use, its design has not changed for over 50 years. Traditional manufacturing methods are difficult to work with and make customization options very limited. By using digital additive manufacturing methods like 3D Scanning, 3D printing and computer simulations, it is possible to offer personalized looks for AFOs by implementing almost any custom pattern expressed in cut-outs on the AFO surface. That kind of perforation simultaneously solves the problem of bad perspiration and air flow. The freedom of graphical expression in those patterns invite the patient to participate in the design process themselves to create an ankle foot orthosis that is their own. That revolutionary twist on the manufacturing and design process empowers the user to take control over their disability to the furthest degree possible and returns the human right of self-determination and independence to them.
Följande rapport presenterar ett examensarbete gällade en omdesign av en ankel-fot-ortos med additiv tillverkning som produktionsmetod, genomförd av en student våren 2020 som del av masterprogrammet Industrial Design vid Jönköpings universitets tekniska högskola. Ortoser för fotleden är de mest föreskrivna ortoserna för underkroppen i hela världen och bärs på ett visuellt påträngande sätt vilket gör att patienterna kan känna sig annorlunda eller utanför för sin funktionsnedsättning. Den sociala stigmatiseringen gör det känslomässigt svårt för många användare att bära en AFO ofta nog för korrekt rehabilitering. Trots dess betydelse och breda användning har designen inte förändrats på över 50 år. Traditionella tillverkningsmetoder är svåra att arbeta med och begränsar alternativen för anpassning. Genom att använda digitala metoder för additiv tillverkning som 3D-skanning, 3D-utskrift och datorsimuleringar är det möjligt att erbjuda ett personligt utseende för AFO genom att införa en stor mängd anpassade mönster i form av utskärningar på AFO-ytan. Denna typ av perforering löser samtidigt problemet med svett och dåligt luftflöde. Friheten för grafiskt uttryck genom dessa mönster låter patienten delta i själva designprocessen för att fotledsortosen ska kännas som deras egen. Detta nya synsätt på utveckling på tillverknings- och designprocessen gör det möjligt för användaren att ta kontroll över sin funktionsnedsättning i största möjliga grad och återställer känslan av självständighet.

碩士
國立臺北科技大學
機電整合研究所
104
In recent years, owing to Additive Manufacturing Technology advances, it is widely used in the field. (It’s prevailing in the field.) As far as the market concerned, it could giving up the conventional subtractive manufacturing, we took additive manufacturing method and even provided with higher efficiency and reduced the cost. More and more companies participated, and as more and more fields could be commercial used. This application included printing ingredients of food.To introduce Additive Manufacturing Technology to more people, a 3D printing pen for food material was developed in this thesis. The 3D printing pen for food material combined the 3D printing machine for food material with 3D printing pen, the user could operate and control it to draw the pattern with their mind; otherwise, this study improved the present container which was syringe piston and used by mostly machines to the utility container which was compressed and made up of silica gel.The machine could print many materials, such as paste, chocolate, butter and mayonnaise…etc. In comparison with the utility container and the present container in the same condition, the utility container increased 35% volume.

碩士
東海大學
食品科學系
107
3D food printing technology is one of the most popular technologies now today, which main purpose is to print food materials with a three-dimensional structure through a 3D printing machine. In this experiment, high methoxyl pectin was used as substrate, pectin jelly candy was printed by using 3D printing technology. Investigate the effects different concentrations of pectin solution of 10-16 %(w/v) on the printing of pectin jelly candy by 3D printing. The results showed that the water activity of the pectin jelly candy in different pectin concentrations were lower than that of the general microbial growth, which water content was less than 25 % when pectin was added more than 12 % (w/v). The rheological property results showed that the viscosity of each pectin jelly candy decreased when the shear rate increased, where shear thinning fluid were indicated by means of the material could be extruded easily. Pectin jelly candy with 14 %(w/v) had better storage modulus and loss modulus, was no obvious structural collapse on the printed product that; Maintaining a good target pattern and graphic height. Printer parameters of nozzle height of 1.5 mm, the extrusion rate of 0.030 cm3/s, the printed layer height is 1.5 mm, nozzle moving speed of 10 mm/s, and the nozzle diameter of 2 mm, showed no obvious structural collapse while maintaining good target pattern and pattern height. In physical property analysis, 14 % (w/v) pectin jelly candy showed better cohesiveness and springiness, than the other. For preservation analysis, pectin jelly candy stored 0 to 2 days showed a significant decrease in height, whereas no significant difference showed between 3 to 6 days. The water activity showed same trend with the height of stored pectin jelly candy, where no significant difference after the fourth day. In conclusion, when 14 % (w/v) pectin jelly candy, appropriate printer parameter conditions were used, a finer pattern and; target product height could be printed.

碩士
國立臺灣科技大學
機械工程系
107
The study covers self-assembly 3D printer as 2D image printing system, all software, and machine structure is self-designed and constructed, including Electrical and Mechanical control system, printing material and nozzle, etc. Among then, machine structure is considered its steadiness and supports, passed heavy load test to confirm the functionality of strength, then put on the ponder carrier and nozzle to observe the consequences affected by ponders and different type of nozzles by the electron microscope. 　　The human-machine interface of 2D image printing divides into two types. The first one is using a self-design APP to control the image of the machine, then converts into G-Code file, and leverages dot matrix pen to draw the 2D image by controlling software. The second is controlling the machine to execute the ponder-printing by G-Code file and implement into coffee latte art images. 　　The study result indicates that the dot matrix pen can reveal the original image correctly according to the pixel sizes and modify accordingly. Meanwhile, the advantages of using mobile gadgets as software development and operation environment showcase the convenience of photo taking and re-print directly with APP. The result concludes dot matrix pen is more easy to maintain the printing quality under the limited resolution of 2D image; However, ponder format could only apply for simple image printing, which means better image quality needs further factors consideration related to ponder temperature, humidity, and ponder size, etc.

3D food printing is a recent promising technology to break cultural barriers by introducing new food sources as microalgae, through innovative food shapes and textures, in a resource scarce world, unfeasible with the current intensive meat and agriculture industries. The present work intended to create an innovative gluten-free cereal snack nutritionally improved by incorporation of microalgae Chlorella vulgaris and Arthrospira platensis (Spirulina) using three-dimensional (3D) printing technology. Furthermore, design settings alterations were performed, registered, and presented in a poster, to explore the creative reach of this technology. From control and different percentage microalgae doughs (5-30%), the ones with most adequate rheology and texture properties for a correct printing process were selected and baked. Nutritional characterisation of the control and 5% microalgae-containing snacks was thus performed, including their total protein and fatty acid content, ashes, humidity, water activity, energy, and carbohydrates, as well as total phenolics, pigments and antioxidant activity. Physical traits of snacks including their colour and dimensions were also analysed. Control snacks presented a lighter and yellow colour compared to snacks containing Chlorella and Spirulina, which had higher green chromaticity, resulting from the natural colour of the biomass. Nutritional characterization revealed Chlorella- and Spirulina-containing snacks had both higher contents of protein and essential minerals than control snack. Overall, 5% Spirulina-containing snacks presented the most promising nutritional and sensory performance with higher antioxidant activity, mineral and protein content. 3D food printing is still limited to the built-in computer assisted design (CAD) software that printers provide. Incorporation of 5% Spirulina improved the nutritional characterization and consumer’s perception of gluten-free products incorporating microalgae. Even so, microalgae incorporation in gluten-free foods using 3D printing requires further studying to allow its commercialization in the food market, while helping to provide consumers a more sustainable diet and respond to the current scarcity of food resources.
A impressão 3D de alimentos é uma tecnologia relativamente recente que promete quebrar barreiras tanto pela introdução de novos ingredientes, como as microalgas, como pelas formas e texturas completamente inovadoras. Este recurso toma particular importância dada a escassez de recursos que a humanidade enfrenta aliada aos efeitos advindos do aquecimento global e dos seus percursores, incluindo a agricultura e a exploração pecuária intensiva. No presente trabalho desenvolveu-se um snack cerealífero, isento de glúten e nutricionalmente melhorado através da incorporação de uma microalga, Chlorella vulgaris, ou uma cianobactéria, Arthrospira platensis, utilizando impressão tridimensional (3D). Vários snacks foram impressos com uma forma previamente otimizada (pata de pato), um design que se encontra incorporado no software de design assistido por computador (CAD) da impressora utilizada (Foodini – Natural Machines, Spain). A formulação das massas dos snacks controlo consistiu numa mistura de duas farinhas isentas de glúten (em igual proporção) - milho e arroz, sal, amido de milho e goma xantana (agente espessante), sendo a mistura homogeneizada antes de se adicionar os líquidos, azeite e água. No caso das massas contendo microalgas ou cianobactérias (incorporações de 5 a 30%), as farinhas e amido de milho foram proporcionalmente substituídas pela biomassa. Para aferir quais as melhores massas em termos de capacidade de impressão, todas as formulações foram submetidas a vários ensaios reológicos (varrimentos de tensão, frequência, tempo e ainda curvas de viscosidade) e de textura (teste TPA - adesividade, coesividade e firmeza). De acordo com os resultados obtidos foram selecionadas para as restantes análises as massas de controlo e com incorporação de 5% de biomassa, tanto de Chlorella como de Spirulina. Estas massas foram impressas com o design previamente mencionado e tratados termicamente num forno industrial de convecção a 180 ºC durante 6 min e 30 s. Adicionalmente, foram avaliadas diferentes condições de impressão que têm impacto na definição gráfica do produto final, nomeadamente, o fator de preenchimento (%), a altura (cm) da ponta do cartucho na primeira camada, a espessura das camadas, o tamanho da ponta do cartucho e a velocidade de impressão. Verificou-se que, embora exista a possibilidade de alterar definições de impressão, tais alterações afetam o design incorporado na impressora, e a criação de um design original sem erros, implicando um conhecimento profundo do funcionamento da impressora, cujo utilizador comum não possui. A cor dos snacks, que é um fator determinante da aceitação final do produto, foi avaliada de acordo com o Colour Space International Comission on Illumination (CIE), avaliando-se a cor dos snacks antes e após o processo de cozimento. Os resultados foram expressos em termos de luminosidade (L*), cromaticidade verde (a*) e amarela (b*) e ainda diferença de cor (ΔE*) em relação ao controlo, como quanto ao efeito do processo de cozedura. De forma a realizar a caracterização nutricional e bioquímica dos snacks, estes foram triturados utilizando um processador industrial com um crivo de 0.5 mm. As dimensões dos snacks também foram analisadas em termos de peso, espessura, comprimento e largura. Também a atividade de água foi analisada à temperatura ambiente e em amostras independentes. O teor humidade dos snacks foi quantificado pelo método de referência, através de diferenças de peso inicial em amostras de cada formulação, submetidas a uma temperatura constante (105 ºC), até que variações de peso não se verificassem. Para determinar o conteúdo em cinzas, os snacks cozinhados foram incinerados até serem convertidos a um pó cinza-claro. A quantidade total de ácidos gordos foi determinada através de hidrólise, seguida de centrifugação, o que permitiu a separação por polaridade, e consequentemente, a extração dos lípidos (menos densos), que foram posteriormente secos durante 3 dias e pesados. A quantidade total de proteínas foi determinada através da quantificação do nitrogénio, utilizando o método DUMAS. A atividade antioxidante foi avaliada através de dois métodos: ferric reducing ability of plasma (FRAP) e 2,2-difenil-1-picril-hidrazil-hidrato (DPPH), sendo que os fenólicos totais foram também aferidos de acordo com Mohankumar et al. (2018), baseado na reação com o reagente de Folin-Ciocalteu. Por fim, também os pigmentos, incluindo clorofila a, b e carotenoides, foram quantificados. Todas as análises foram realizadas com triplicados de amostras independentes. Os snacks analisados foram submetidos à avaliação de um painel sensorial com provadores não treinados. Classificaram-se os atributos: cor, textura, aspeto, aroma, sabor e avaliação geral sob forma de escala hedónica de 7 pontos - de (1) desgosto muito a (7) gosto muito. A intenção de comprar foi também determinada utilizando uma escala de 7 pontos (de (1) nunca compraria a (7) compraria sempre). Os snacks que apresentaram melhores características de impressão continham entre 0 a 5% de incorporação de biomassa de microalgas, sendo que as restantes formulações, quer de Chlorella ou Spirulina apresentaram viscosidade pouco adequada para impressão. Para concentrações de biomassa mais elevadas, obtiveram-se designs com erros de impressão, sendo os mesmos mais acentuados para os níveis de incorporação mais elevados. As dimensões dos snacks não foram afetadas significativamente pela incorporação de microalgas em comparação com snacks sem as mesmas. No entanto, verificou-se uma redução substancial da espessura, peso e restantes medidas após o processo de cozedura. Em termos de coloração, foi possível aferir que a incorporação de 5% de biomassa de Chlorella vulgaris levou ao escurecimento e aumento da cromaticidade verde em comparação aos snacks sem esta biomassa, que apresentavam coloração com maior luminosidade e maiores valores de cromaticidade amarela. Já os snacks incorporando 5% de Arthrospira platensis, revelaram uma coloração muito mais escura que as restantes e maior cromaticidade azul e verde no espaço de cor. Verificaram-se diferenças significativas (p < 0.05) entre as amostras com e sem microalga, no que diz respeito a parâmetros reológicos e de textura, sendo possível denotar um aumento de estruturação das massas com o aumento de incorporação de biomassa de microalgas, assim como um aumento da dureza dos snacks. A caracterização nutricional dos snacks possibilitou concluir que os snacks contendo 5% de biomassa de Spirulina apresentavam valores de proteína e minerais essenciais consideravelmente superiores aos restantes snacks, verificando-se o mesmo padrão relativamente à atividade antioxidante e pigmentos (clorofila a e carotenoides), com valores significativamente superiores (p < 0.05). O mesmo aperitivo (5% de biomassa de Arthrospira platensis) foi também o selecionado pelos pelo painel de avaliação sensorial, como sendo o mais apelativo em termos gerais, textura, sabor e aspeto. Como conclusão geral do trabalho realizado, verificou-se que a incorporação de biomassa microalgal permitiu a obtenção de snacks 3D sem glúten, mas com um limite máximo de incorporação de 5% (m/m). Esses snacks apresentaram uma melhoria a nível nutricional, nomeadamente do teor proteico, minerais essenciais e da atividade antioxidante, destacando-se o caso dos snacks com 5% de Arthrospira platensis, comparativamente com o controlo (sem qualquer incorporação de biomassa). A aceitação desses snacks por parte do painel de sensorial, permite perspetivar uma boa aceitação por parte dos consumidores e consequentemente prospetivar um potencial de comercialização. No entanto, a incorporação de microalgas em produtos isentos de glúten, requer ainda mais estudos, de forma que a sua introdução no mercado se torne uma realidade. Uma realidade que poderá ajudar a colmatar a previsível escassez de recursos alimentares e, em simultâneo, contribuir para uma alimentação mais sustentável, particularmente importante para pessoas que não podem consumir glúten.