Дисертації з теми "Food packaging film"
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Mercer, Angela. "Migration studies of plasticizers from PVC film into food." Thesis, De Montfort University, 1990. http://hdl.handle.net/2086/4319.
Повний текст джерелаLin, Shin-Jie. "Development of Edible Packaging for Selected Food Processing Applications." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1349125959.
Повний текст джерелаHAGHIGHI, HOSSEIN. "Sviluppo di film attivi a base di chitosano per packaging alimentare sostenibile." Doctoral thesis, Università degli studi di Modena e Reggio Emilia, 2020. http://hdl.handle.net/11380/1201046.
Повний текст джерелаThe current trend in food packaging is oriented towards the substitution of non-biodegradable petroleum-based polymers by packaging materials that are eco-friendly and can prolong the food shelf life as well. In this context, this Ph.D. project aims to the development of chitosan-based blend films enriched with natural (essential oils) and synthetic (ethyl lauroyl arginate) antimicrobial compounds for sustainable food packaging applications. The overall project has been divided into five main parts. The brief description of each chapter is presented here: Chapter I presents a brief introduction to the recent advances of chitosan-based blend films for food packaging applications. The reason for selecting chitosan as the main biopolymer in this study and literature review concerning blending chitosan with other biopolymers has been described. Chapter II aims to develop blend and bilayer bio-based active films by solvent casting technique, using chitosan and gelatin as biopolymers, glycerol as a plasticizer and ethyl lauroyl arginate (LAE) as an antimicrobial compound. The results showed that blend films had higher tensile strength and elastic modulus and lower water vapor permeability than bilayer films (p<0.05). Bilayer films demonstrated as effective barriers against UV light and showed lower transparency values (p<0.05). FT-IR spectra indicated that interactions existed between chitosan and gelatin due to electrostatic interactions and hydrogen bond formation. However, the addition of LAE did not interfere in the network structure. Active films containing LAE (0.1%, v/v) inhibited the growth of four food bacterial pathogens including Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, and Campylobacter jejuni. Chapter III focuses to develop films based on chitosan-gelatin blend enriched with cinnamon, citronella, pink clove, nutmeg, and thyme essential oils (1%, v/v) and evaluating their physical, optical, mechanical, water barrier and microstructural properties for active food packaging applications. The results confirmed intermolecular interactions between functional groups of the essential oils with the hydroxyl and amino groups of the chitosan-gelatin film network. The incorporation of different essential oils notably improved the UV barrier properties. The developed films, with special regards for those including thyme essential oil, were effective against four common food bacterial pathogens. Chapter IV aims to develop active films based on blending chitosan and polyvinyl alcohol enriched with LAE at different concentrations (1-10%, w/w). The results showed that high LAE levels negatively affected mechanical and water barrier properties. Addition of LAE improved UV barrier properties. The developed active films were effective against four common food bacterial pathogens.
Rocca, Smith Jeancarlo Renzo. "A contribution of understanding the stability of commercial PLA films for food packaging and its surface modifications." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCK004/document.
Повний текст джерелаPoly(lactic acid) (PLA) is a biodegradable and renewable polyester, which is considered as the most promising eco-friendly substitute of conventional plastics. It is mainly used for food packaging applications, but some drawbacks still reduce its applications. On the one hand, its low barrier performance to gases (e.g. O2 and CO2) limits its use for applications requiring low gas transfer, such as modified atmosphere packaging (MAP) or for carbonate beverage packaging. On the other hand, its natural water sensitivity, which contributes to its biodegradation, limits its use for high moisture foods with long shelf life.Other biopolymers such as wheat gluten (WG) can be considered as interesting materials able to increase the PLA performances. WG is much more water sensitive, but it displays better gas barrier properties in dry surroundings. This complementarity in barrier performances drove us to study the development of multilayer complexes PLA-WG-PLA and to open unexplored application scenarios for these biopolymers.This project was thus intended to better understand how food components and use conditions could affect the performances of PLA films, and how these performances could be optimized by additional processing such as surface modifications (e.g. corona treatment and coatings).To that aim, three objectives were targeted:- To study the stability of industrially scale produced PLA films in contact with different molecules (CO2 and water) and in contact with vapour or liquid phases, with different pH, in order to mimic a wide range of food packaging applications.- To better understand the impact of some industrial processes such as corona or hot press treatments on PLA.- To combine PLA with WG layer to produce high barrier and biodegradable complexes.Different approaches coming from food engineering and material engineering were adopted. PLA films were produced at industrial scale by Taghleef Industries with specific surface treatments like corona. Wheat gluten films, coatings and layers were developed and optimized at lab scale as well as the 3-layers PLA-WG-PLA complexes. Different technologies able to mimic industrial processes were considered such as hot press, high pressure homogenization, ultrasounds, wet casting and spin coating. The physical and chemical properties of PLA films were then studied at the bulk and surface levels, from macroscopic to nanometer scale. The functional properties like permeability to gases (e.g. O2 and CO2) and water, gas and vapour sorption, mechanical and surface properties were also investigated.Exposed to CO2, PLA films exhibited a linear sorption behaviour with pressure, but the physical modifications induced by high pressure did not affect its use for food packaging. However, when exposed to moisture in both liquid and vapour state (i.e. environments from 50 to 100 % relative humidity (RH)), PLA was significantly degraded after two months at 50 °C (accelerated test) due to hydrolysis. This chemical deterioration was evidenced by a significant decrease of the molecular weight, which consequently induced a loss of transparency and an increase of the crystallinity. The hydrolysis was accelerated when the chemical potential of water was increased, and it was surprisingly higher for vapour compared to liquid state. In addition, pH did not affect the rate of hydrolysis.Knowing much better the limitation of PLA films, the challenge was to improve its functional properties by combining them with WG, as a high gas barrier bio-sourced and biodegradable polymer. The use of high pressure homogenization produced homogeneous WG coatings, with improved performances. This process was thus selected for making 3 layer complexes by assembly of a wheat gluten layer between two layers of PLA, together with corona treatment and hot press technologies.Corona treatment applied to PLA physically and chemically modified its surface at the nanometer scale (...)
I materiali plastici convenzionali trovano impiego in tutti campi della nostra vita, specialmente nel settore del packaging alimentare, ed in seguito all’utilizzo contaminano e danneggiano il nostro ecosistema. Materiali plastici derivanti da risorse naturali e biodegradabili, come acido polilattico (PLA), sono attualmente disponibili sul mercato anche se caratterizzati da performances inferiori.Questo progetto di dottorato è mirato 1) allo studio della stabilità di film di PLA a varie condizioni di stoccaggio come temperatura, umidità relativa, pH, o esposizione a vapori o gas; 2) a comprendere meglio le influenze di alcuni processi industriali come trattamento corona e hot press nelle proprietà dei film di PLA; 3) a sviluppare complessi multistrato tra film di PLA e di glutine che abbiano proprietà barriera più elevate rispetto ai singoli film.Gli imballaggi a base di PLA sono stati prodotti da Taghleef Industries, produttore leader nel settore e dotato di infrastrutture atte ai trattamenti di modificazione di superfice come il trattamento corona. I film a base di glutine e i coatings sono stati sviluppati e ottimizzati su scala di laboratorio, così come i complessi trilaminari PLA-glutine-PLA.Le proprietà fisiche e chimiche dei film di PLA sono state investigate a livello di superficie, così come a livello di bulk. Diverse tecniche analitiche, provenienti dal campo delle scienze dei materiali e delle scienze degli alimenti, sono state adottate in questo progetto di dottorato come calorimetria differenziale a scansione (DSC), termogravimetria (TGA), cromatografia di esclusione molecolare (SEC), microscopia a forza atomica (AFM), microscopia elettronica a scansione (SEM), spettrofotometria infrarossa a trasformata di Fourier in riflettanza totale attenuata (ATR-FTIR) e spettroscopia fotoelettronica a raggi X (XPS).Le proprietà funzionali come le permeabilità al vapore acqueo (H2O), all’ossigeno (O2), al diossido di carbonio (CO2) o all’elio (He) sono state investigate, cosi come l’assorbimento di gas e/o vapori, le proprietà meccaniche e le proprietà di superfice.Nonostante i film di PLA assorbano linearmente CO2 a pressioni crescenti, l’assorbimento di tale gas è ridotto a basse pressioni in modo da non modificare le sue proprietà fisiche – come contrariamente osservato quando il PLA è esposto a CO2 ad alte pressioni – e da non influenzare negativamente il suo utilizzo come imballaggio alimentare. Ad ogni modo, quando i film di PLA sono esposti ad ambienti umidi, o quando sono immersi in acqua liquida, sono significativamente degradati per idrolisi dopo due mesi di stoccaggio a 50 °C (test accelerato). Questo deterioramento chimico è stato evidenziato da una significativa riduzione del peso molecolare del PLA che, conseguentemente, induce una sua perdita di trasparenza e ne incrementa la sua cristallinità. Inoltre, è stato evidenziato che il pH non influenza la velocità di idrolisi. Quest’informazione ha importanza pratica per possibili utilizzi di PLA come imballaggio di alimenti ad alta umidità.Il glutine è stato scelto per le sue alte proprietà barriera, quando è protetto da ambienti ad alta umidità. Si è visto che l’incorporazione di lipidi non porta con sé grandi miglioramenti nelle performances dei film a base di glutine. Invece, l’utilizzo della tecnologia di omogeneizzazione ad alte pressioni permette una migliore dispersione del glutine, ottenendo film più omogenei e con migliori proprietà funzionali. Questa tecnologia è stata quindi scelta per produrre i complessi multistrato, intercalando i film di glutine tra due film di PLA, usando il trattamento hot press (10 MPa, 130 °C, 10 min). Si è osservato che il trattamento hot press modifica le proprietà dei film di PLA, di glutine e dei film multistrato Hot press induce cristallizzazione in PLA, e conseguentemente aumenta le sue proprietà barriera complessive, approssimativamente al 40 % all’acqua e al 60 % all’ossigeno (...)
Los materiales plásticos tradicionales son utilizados en todos los campos de nuestra vida y en particular modo como embajales de productos alimenticios; los cuales después de ser utilizados contaminan y dañan nuesto medio ambiente. Materiales plásticos derivados de recursos naturales y biodegradables, como el ácido poliláctico (PLA) se encuentran actualmente disponibles en el mercado a pesar de sus menores performances. Este proyecto de doctorado está orientado 1) al estudio de la estabilidad de películas de PLA bajo diferentes condiciones como temperatura, humedad relativa, pH o exposición a vapores o gases, 2) comprender los efectos en las propiedades de las películas de PLA de algunos procesos industriales como el tratamiento corona y hot press, 3) desarrollar complejos multicapas de PLA y gluten que tengan propiedades barrera mejores que las de las películas individuales.Los embalajes a base de PLA han sido producidos por Taghleef Industries, productor líder en el sector y dotado de las infraestructuras industriales adaptadas a los tratamientos superficiales como el tratamiento corona. Las películas de gluten y los coatings han sido desarrollados a escala de laboratorio, así como los complejos tricapa PLA-gluten-PLA.Las propiedades físicas y químicas de las películas de PLA han sido investigadas a nivel de superficie así como a nivel de bulk. Diferentes técnicas de análisis, frecuentemente utilizadas en los campos de las ciencias de los materiales y de las ciencias de los alimentos, han sido empleadas en este proyecto como calorimetría diferencial de barrido (DSC), análisis termogravimétrico (TGA), cromotagrafía de exclusión por tamaño (SEC), microscopía de fuerza atómica (AFM), microscopía electrónica de barrido (SEM), espectroscopía de infrarrojos por transformada de Fourier con reflectancia total atenuada (ATR-FTIR) y espectroscopía fotoelectrónica de rayos X (XPS).Las propiedades funcionales de los embalajes como las permeabilidades al vapor de agua, al oxígeno (O2), al dióxido de carbono (CO2) o al helio (He) han sido investigadas, asi como la absorción de gases/vapores, las propiedades mecánicas y las propiedades superficiales. A pesar de que las películas de PLA absorven linealmente CO2 a presiones mayores, la absorción del gas es reducida a bajas presiones y no modifica las propiedades físicas del PLA, como contrariamente sucede cuando el PLA es expuesto a altas presiones de CO2. Por lo tanto, su influencia en las propiedades funcionales del PLA es mínima en las normales aplicaciones alimentarias. De todos modos cuando los embalajes de PLA son expuestos a ambientes húmedos o cuando son sumergidos en agua, procesos de hidrólisis los degradan significativamente después de dos meses de conservación a 50 °C (test acelerado). Este deterioramiento químico ha sido evidenciado por una significativa reducción del peso molecular del PLA, que en consecuencia induce una pérdida de transparencia y un aumento de su cristalinidad. Además, se ha observado que el pH no influye en la velocidad de hidrólisis. Esta información tiene una importancia práctica para posibles usos del PLA como embalajes de alimentos a alta humedad. El gluten ha sido elegido por sus altas propiedades barrera cuando es protegido de ambientes a alta humedad. La incorporación de lípidos en las películas de gluten no han mejorado sus performances. Pero la tecnología de la homogenización a altas presiones ha permitido mejorar la dispersión del gluten, obteniendo películas más homogéneas y con mejores propiedades funcionales. Esta tecnología ha sido, por lo tanto, elegida para producir los complejos multicapa, intercalando las películas de gluten entre dos de PLA, utilizando el tratamiendo hot press (10 MPa, 130 °C, 10 min) (...)
Lara, Lledó Marta Inés. "Antimicrobial packaging system for minimally processed fruit." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/61388.
Повний текст джерела[ES] En la presente Tesis Doctoral se han desarrollado materiales de envase activo antimicrobiano, a escala laboratorio y a escala semi-industrial, con el objetivo de reducir la proliferación de la flora natural de la fruta pelada y cortada y extender su vida útil. Se han desarrollo distintos prototipos para su posterior aplicación industrial Previo al desarrollo de los materiales de envase, se ha realizado una selección de agentes activos más idóneos. Para ello se han estudiado mediante ensayos in vitro las propiedades antimicrobianas de agentes activos volátiles, citral, hexanal y linalool y diferentes mezclas de los mismos, frente a distintos microorganismos típicos del deterioro de las frutas, mohos y levaduras, concluyendo que la efectividad de la mezcla de los tres es superior a la suma de la efectividad de los activos de forma individual. Así mismo, también se han seleccionado antimicrobianos no volátiles como el sorbato potásico y benzoato sódico, los cuáles son ampliamente empleados en la industria alimentaria debido principalmente a sus propiedades antifúngicas. Con los agentes activos seleccionados, se han desarrollado películas monocapa de polipropileno (PP) con distintas concentraciones de la mezcla activa, citral, hexanal y linalool, a escala laboratorio, mediante técnicas de extrusión, y películas bicapa a escala semi-industrial con distintos espesores de capa activa mediante coextrusión. Por otra parte, se desarrollaron bandejas activas a escala semi-industrial mediante termoconformado de láminas obtenidas por coextrusión de compuestos de PP y etilvinilaceteto (EVA) con sorbato potásico o benzoato sódico como agentes antimicrobianos. Se han evaluado las propiedades mecánicas, barrera y térmicas de los materiales activos desarrollados, así como su sellabilidad y transparencia. En general, las propiedades de los polímeros no se vieron afectadas de manera relevante. Sin embargo, las bandejas activas perdieron su carácter transparente debido a la incorporación de los agentes activos no volátiles. Se ha estudiado la cinética de liberación de los compuestos activos volátiles y no volátiles a distintas temperaturas, determinando los coeficientes de difusión de los agentes activos mediante el ajuste a modelos matemáticos de difusión basados en la Segunda Ley de Fick. Entre los agentes volátiles, el hexanal mostró un mayor coeficiente de difusión seguido de citral y linalool. Por otra parte, no hubo apenas diferencia en los coeficientes de difusión del sorbato potásico y benzoato sódico, siendo éstos del mismo orden de magnitud. Igualmente, se han realizado diferentes experimentos in vitro a distintas temperaturas para determinar las propiedades antimicrobianas de los materiales desarrollados. En general, los materiales activos presentan una elevada capacidad antimicrobiana que se ve potenciada al aumentar la temperatura de exposición. Una vez evaluadas las características de los materiales desarrollados, se han efectuado ensayos de envasado de naranja y piña pelada y cortada con las películas y las bandejas activas y con la combinación del sistema de envase bandeja activa termosellada con la película activa. En general, el sistema de envase activo mejoró la conservación de la fruta por un mayor tiempo, entre 2 y 7 días para la naranja y piña, respectivamente, presentando una gran capacidad antimicrobiana y manteniendo los parámetros de calidad de la fruta en niveles estables por un mayor tiempo. Por último, se ha estudiado la seguridad de estos materiales de acuerdo a la legislación de materiales en contacto con alimentos y la legislación alimentaria europea, concluyendo que los materiales activos desarrollados no presentan preocupación para la seguridad de los consumidores.
[CAT] En la present Tesi Doctoral s'han desenvolupat materials d'envasament actiu antimicrobià, a escala de laboratori i a escala semi-industrial amb l'objectiu de reduir la proliferació de la flora natural de la fruita pelada i tallada i estendre la seua vida útil. S'han desenvolupament diferents prototips per a la seua posterior aplicació industrial. Previ al desenvolupament dels materials actius, s'han seleccionat els agents actius mes idonis estudiant mitjançant assajos in vitro les propietats antimicrobianes d'agents actius volàtils, citral, hexanal i linalool i diferents mescles dels mateixos, enfront de diferents microorganismes típics de la deterioració de les fruites -floridures i llevats- concloent que l'efectivitat de la mescla dels tres és superior a la suma de l'efectivitat dels actius de forma individual. Així mateix, s'han seleccionat antimicrobians no volàtils, sorbat potàssic i benzoat sòdic, els quals son àmpliament empleats a l'industria alimentaria per les seues propietats antifúngiques. Amb els agents actius seleccionats, s'han desenvolupat pel·lícules monocapa de polipropilè (PP) amb diferents concentracions de la mescla activa, citral, hexanal i linalool, a escala laboratori, mitjançant tècniques d'extrusió, i pel·lícules bicapa a escala semi-industrial amb diferents espessors de capa activa mitjançant coextrusió. D'altra banda, s'han desenvolupat safates actives a escala semi-industrial mitjançant termoconformació de làmines obtingudes per coextrusió de compostos de PP i etil vinil acetat (EVA) amb sorbat potàssic o benzoat sòdic com a agents antimicrobians. S'han avaluat les propietats mecàniques, barrera i tèrmiques dels materials actius desenvolupats, així com la seua sellabilidad i transparència. En general, les propietats dels polímers no es van veure afectades de manera rellevant. No obstant això, les safates actives van perdre el seu caràcter transparent a causa de la incorporació dels agents actius no volàtils. S'ha estudiat la cinètica d'alliberament dels compostos actius volàtils i no volàtils a diferents temperatures, determinant els coeficients de difusió dels agents actius mitjançant l'ajust a models matemàtics de difusió basats en la Segona Llei de Fick. Entre els agents volàtils, l' hexanal va mostrar un major coeficient de difusió seguit de citral i linalool. D'altra banda, no va haver-hi a penes diferències en els coeficients de difusió del sorbat potàssic i benzoat sòdic, sent aquests del mateix ordre de magnitud. Igualment, s'han realitzat diferents experiments in vitro a diferents temperatures per determinar les propietats antimicrobianes dels materials desenvolupats. En general, els materials actius presenten una elevada capacitat antimicrobiana que es veu potenciada en augmentar la temperatura d'exposició. Una vegada avaluades les característiques dels materials desenvolupats s'han efectuat assajos d'envasament de taronja i pinya pelada i tallada amb la safata, la pel·lícula activa i la seva combinació (sistema d'envàs actiu). En general, el sistema d'envàs actiu va millorar la conservació de la fruita per un major temps, entre 2 i 7 dies per a la taronja i pinya respectivament, presentant una gran capacitat antimicrobiana i mantenint els paràmetres de qualitat de la fruita en nivells estables per un major temps. Finalment, s'ha estudiat la seguretat d'aquests materials d'acord a la legislació de materials en contacte amb aliments i la legislació alimentària europea, concloent que els materials actius desenvolupats no presenten preocupació per a la seguretat dels consumidors.
Lara Lledó, MI. (2016). Antimicrobial packaging system for minimally processed fruit [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61388
TESIS
Premiado
Amankwaah, Collins. "Incorporation of selected plant extracts into edible chitosan films and the effect on the antiviral, antibacterial and mechanical properties of the material." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366220367.
Повний текст джерелаMallia, Ilaria. "Sviluppo di una nuova metodologia per la misura della permeabilità di film plastici ad uso alimentare." Thesis, Università degli Studi di Catania, 2011. http://hdl.handle.net/10761/239.
Повний текст джерелаPadeloglou, Elin, and Moa Ullgren. "Mindre plastfilm vid lastsäkring : En fallstudie hos Martin & Servera." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-95291.
Повний текст джерелаSilva, Mariana Rodrigues Ferreira da. "Active and intelligent bionanocomposites for food packaging." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22400.
Повний текст джерелаA produção de plásticos, baseados no uso de combustíveis fósseis, está a aumentar e estima-se que esta tendência continuará no futuro com impactos ambientais consideráveis. Os bioplásticos são uma alternativa amiga do ambiente. Biopolímeros como quitosana já foram adotados com sucesso para produzir bioplásticos que agem como substitutos do plástico em embalagem. A quitosana foi selecionada devido às suas numerosas vantagens para embalagem alimentar, principalmente devido às suas atividades antioxidantes e antimicrobiana. Por outro lado, o dióxido de titânio foi selecionado como aditivo devido à sua capacidade de retirar oxigénio do ambiente e devido à possibilidade de poder ser facilmente funcionalizado para a formação de um sensor. Isto permitiria a formação de uma embalagem ativa e inteligente na proteção do alimento. Assim, nanopartículas homogéneas arredondadas e monofásicas de anatase de dióxido de titânio (TiO2) foram usadas para melhorar os filmes de quitosana, criando um bionanocompósito. Estas nanopartículas de TiO2 foram produzidas por síntese hidrotermal, tendo sido otimizadas as condições de síntese, como a temperatura e tempo, para selecionar as condições que originam as nanopartículas com as caraterísticas desejadas. As condições escolhidas para a produção do TiO2 foram 200 ºC e 2,5 h devido ao tamanho, dispersão e tipo de nanoparticulas de TiO2 produzidas. Os filmes de quitosana foram preparados com cerca de 9 mg de nanopartículas de TiO2. Para criar uma embalagem ativa e inteligente compostos fenólicos (principalmente antocianinas) de arroz preto (Oryza sativa L. Indica) foram adicionados para funcionalizar o TiO2 (4,1 mg de extrato por filme). Os filmes foram caracterizados em relação à sua atividade antioxidante, humidade, solubilidade, hidrofobicidade da superfície e propriedades mecânicas. Os melhores resultados foram obtidos nos filmes com nanopartículas e compostos fenólicos e foi demonstrado que a forma como cada componente é adicionado altera as suas propriedades. Os melhores resultados foram o aumento da atividade antioxidante, diminuição da solubilidade e da elasticidade, elongação e resistência à tração no filme composto por pigmento e TiO2,. No entanto nestes últimos três parâmetros, a sua diminuição pode ser um aspeto positivo ou negativo dependendo das propriedades desejadas para o filme e o produto alimentar a embalar
Plastic production based in fossil fuels is rising, and predictions supports it continuous and enhanced use, with consequent environmental damage. Bioplastics are an environmentally friendly alternative. Biopolymers as chitosan have already been successfully used to produce bioplastics that act as plastic substitutes in packaging. Chitosan was chosen for its numerous advantages for food packaging namely due to its antioxidant and antimicrobial activities. On the other hand, TiO2 was selected due to its oxygen scavenging ability and due to its possibility to be easily functionalised to create a sensor. This would allow the construction of an active and intelligent packaging for food protection. Thus, monophasic anatase homogeneous round-shaped nanoparticles of titanium dioxide (TiO2) were used as filler to improve the chitosan films, creating a bionanocomposite. These TiO2 nanoparticles were produced via a hydrothermal method and its synthesis was optimized testing various reaction times and temperatures to find the conditions that create TiO2 nanoparticles with the desired features. The conditions used for the chosen TiO2 were 200 ºC and 2.5 h due to the size, dispersion and TiO2 of the nanoparticles produced. The chitosan films were prepared with about 9 mg of TiO2 nanoparticles. To develop an active and intelligent food packaging, phenolic compounds (mainly anthocyanins) from black rice (Oryza sativa L. Indica) were used to functionalise the TiO2 (4.1 mg of extract in each film). The films were characterised regarding its antioxidant activity, humidity, solubility, surface hydrophilicity and mechanical properties. The best results were from films with both nanoparticles and phenolic compounds, and it was established that the order in which they are added alters its properties. The more notable improvements are an increase in antioxidant activity and a decrease in solubility, elasticity, elongation and tensile strength in the film containing pigment and TiO2. However, the reduction of the later three properties can either be positive or negative, it depends on desired properties for the film for a chosen food product
Motedayen, Ali Akbar. "Novel stratified self-assembled Polyehtylene-Organoclay films for food packaging." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT156.
Повний текст джерелаInspired by the traditional Layer-by-Layer (LbL) assembly technique, this PhD study demonstrates the first effort to develop a novel methodology for multilayer self-assembly on the basis of hydrophobic interactions and further physical adsorption to fabricate stratified Polyethylene(LLDPE)-organoclay(OMMT) nano-enabled composite film. In contrary to the electrostatic LbL technique, here, the multilayer films were synthesized by starting from an uncharged apolar polymer substrate and successively depositing apolar organoclay and uncharged apolar PE layers with subsequent repeating depositions. The alternate variation of contact angle (85° average for organoclay and 107° for PE layers) confirmed the profilometry and the scanning electron microscopy results as well as the linear growth pattern, i.e. the successful highly stratified assembly of repetitive bilayers comprised of 450 nm organoclays and 2.25 µm PE layers. Further characterization tests were performed to evaluate the effect of the main identified process parameters (concentration, temperature, rinsing and drying steps, and solvent type) variation on the formation and thickness growth of the films. As a consequence, the high dependence of the self-assembly’s growth to the tested process parameters was showed by the obtained experimental results. The barrier properties of the multilayer films were also evaluated by characterizing the Water vapour, Oxygen (O2), and Carbon dioxide (CO2) permeability as well as the water vapour sorption. A 5-bilayer (OMMT/PE) coating (∼14 µm thick) reduced the O2 permeability of a 160 µm-thick PE film by 84.4% and the CO2 permeability by 70%, while the WVP was reduced by 45%. These permeability reductions obtained by only 2.4 v/v % of nanoclay addition level were found to be significantly greater compared to the reduction values reported in the literature for prepared blend PE/organoclay nanocomposites. This knowledge can be used in the establishment of an approach to produce stratified micro/nanostructures with tailored barrier properties for food packaging application
Requena, Peris Raquel. "Multilayer biodegradable active films based on PHBV for food packaging." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/110079.
Повний текст джерелаBiodegradable active films based on PHBV, combined with other biopolymers (PLA and starch) and different antimicrobial compounds (essential oils (EO)), were developed and characterized as to their functional and structural properties to obtain materials that better meet food packaging requirements. Plasticization of PHBV was analysed by using different compounds to enhance the PHBV mechanical performance. Likewise, different active compounds (oregano and clove EO, as well as their respective main compounds, carvacrol (CA) and eugenol (EU)) were incorporated into PHBV bilayer films by spraying the actives between two thermo-compressed monolayers. The potential synergy between different EO compounds and their applications to different food when incorporated into PHBV films was also analysed. Multilayer antimicrobial films combining polar (starch) and non-polar (polyester) sheets, incorporating CA, either by spraying it between both layers or incorporating it in the polyester casting solution, were developed to optimise the material functionality. Bioactive xylans and cellulosic fractions from rice husk, which are useful for food packaging applications, were obtained by using an eco-friendlier valorization process based on subcritical water extraction. Although the addition of polyethylene glycol (PEG) of different molecular weight and lauric acid significantly decreased the stiffness and the resistance to break of PHBV films, only PEG1000 yielded more extensible films. Nonetheless, additional strategies would be required to adapt PHBV mechanical properties to certain packaging requirements. Spraying actives at the interface of both PHBV monolayers produced antimicrobial films with appropriate physical properties. The release of the actives from the films was adequate to control the growth of E. coli and L. innocua in vitro. Both actives, CA and EU were effectively released into different food simulants. The release rate was enhanced when the polarity of the simulants decreased, but it fell markedly in fatty systems. The most remarkable synergistic effect for the EO compounds was observed for CA/cinnamaldehyde blends for both bacteria but using different compound ratios. Thus, the results allowed for the optimization of the dose of actives used for food application, thus minimizing their sensory impact. PHBV films with active EO compounds were highly effective against L. innocua and E. coli in the in vitro tests, but they were much less effective in foods. Likewise, no correlation between the amount of active that migrated to the food and the antibacterial effect was observed, which reflected that many compositional factors affect the availability of the antimicrobials to exert their action on a specific food. The 75:25 PLA-PHBV formulation with PEG1000 exhibited the best properties in terms of physical properties and, thus it was used to be the carrier of CA by casting and to develop bilayers with starch. Incorporating CA by spraying it between the polyester and starch sheets was not effective at retaining this active in the bilayers. However, the incorporation of CA into casted polyester films was highly effective at providing practically total CA retention, which led to a notable antimicrobial activity. Moreover, these bilayers exhibited highly improved tensile and water vapour barrier capacity with respect to the starch monolayer. The rice husk valorization, based on subcritical water extraction, allowed for obtaining better preserved hemicelluloses, with antioxidant and antibacterial activity, useful as additives for food or food packaging applications, and cellulosic reinforcing agents to develop biocomposites with enhanced mechanical performance.
Es van desenvolupar pel·lícules biodegradables actives a base de PHBV, combinades amb altres biopolímers (PLA i midó) i diferents compostos antimicrobians (olis essencials (OE)), les quals es van caracteritzar quant a les seues propietats funcionals i estructurals a fi d'obtindre materials que complisquen millor els requisits d'envasament d'aliments. La plastificació del PHBV es va dur a terme per mitjà de diferents compostos amb l'objectiu de millorar el rendiment mecànic dels films. Així mateix, es van incorporar diferents actius (OE d'orenga i clau, així com els seus respectius compostos majoritaris, carvacrol (CA) i eugenol (EU)) en pel·lícules bicapa de PHBV polvoritzant els actius entre dos monocapas, obtingudes per termocompressió. També es va analitzar la potencial sinergia entre diferents compostos d'OE, així com les seues aplicacions a diferents aliments quan s'incorporen en pel·lícules bicapa de PHBV. Es van desenvolupar pel·lícules antimicrobianes multicapa on es combinaren làmines polars (midó) i apolars (polièsters) i carvacrol, ja siga polvoritzat entre ambdós capes o incorporat en la solució filmogénica de polièsters, a fi d'optimitzar la funcionalitat del material. El procés de valoració de la corfeta d'arròs, basat en extracció amb aigua subcrítica, va permetre obtindre xilans bioactius i fraccions cel·lulòsiques amb potencials aplicacions en l'envasament d'aliments. A pesar que l'addició de polietilenglicol (PEG) de diferent pes molecular o àcid làuric va disminuir significativament la rigidesa i la resistència de les pel·lícules de PHBV, només PEG1000 va donar lloc a pel·lícules més extensibles. No obstant això, estratègies addicionals varen ser necessàries a fi d'adaptar les propietats mecàniques dels films de PHBV a certs requisits d'envasament. La polvorització d'actius a la interfase d'ambdós monocapes de PHBV va generar pel·lícules antimicrobianes amb propietats físiques adequades. L'alliberament dels actius des de les pel·lícules va permetre controlar el creixement d'Escherichia coli i Listeria innocua en assajos in vitro. Ambdós actius, CA i EU, es van alliberar de manera efectiva en els diferents simulantes alimentaris. La taxa d'alliberament va millorar quan va disminuir la polaritat dels sistemes aquosos. L'efecte sinèrgic més notable per als compostos d'OE es va observar per a les mescles de CA/cinnamaldehído per a ambdós bacteris, però utilitzant diferents proporcions. D'esta manera, els resultats van permetre l'optimització de la dosi d'actius utilitzats per a l'aplicació en aliments, minimitzant així el seu impacte sensorial. Les pel·lícules de PHBV amb actius d'OE van ser altament efectives front L. innocua i E. coli en les proves in vitro, però van ser molt menys efectives en aliments. Així mateix, no es va observar cap correlació entre la quantitat d'actiu migrada a l'aliment i l'efecte antibacterià en les diferents matrius, la qual cosa reflectix que hi ha molts factors composicionals que afecten la efectivitat del dels compostos actius per a exercir la seua acció sobre un aliment en concret. La formulació 75:25 PLA-PHBV amb PEG1000 va exhibir les millors propietats físiques i, per tant, es va utilitzar com a suport del CA per mitjà de càsting, així com per a desenvolupar bicapes amb midó. La incorporació de CA polvoritzat entre les làmines de polièsters i midó no va ser eficaç per a retindre el compost actiu en la bicapa. No obstan, la incorporació de CA en pel·lícules de polièster per càsting va permetre una retenció de CA pràcticament total, la que va conduir a una notable activitat antimicrobiana. A més, estes bicapas van exhibir una capacitat de barrera al vapor d'aigua i a la tracció altament millorades respecte a la monocapa de midó. La valoració de la corfa d'arròs, basada en l'extracció amb aigua subcrítica, va permetre obtindre fraccions hemicelulósiques millor conservades, amb activ
Requena Peris, R. (2018). Multilayer biodegradable active films based on PHBV for food packaging [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/110079
TESIS
Ruellan, Alexandre. "Conception raisonnée à l’aide de la formulation et du procédé d’un film souple biosourcé et biodégradable pour l’emballage alimentaire." Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0032.
Повний текст джерелаThe use of renewable resources and the production of biodegradable materials are appropriate solutions to reduce the environmental impact of the sector of plastics. There is thus a demand for eco-friendly products on the market provided they obtain performance equal or superior to synthetic materials currently used. One possibility, widely used in the food sector, to achieve efficient packaging film is the creation of multilayer structures by combining advantageous properties of different plastics. In this case, recycling of materials is difficult and the biodegradability of the packaging becomes relevant. This study proposes designing biobased and biodegradable films for food packaging from polylactide and co- products of the oil mill industry as additives, in particular the deodorization condensates. Among these lasts, the partial solubility of their molecules and the synergetic effect of the liquid and solid fat components at room temperature, depending on their alkyl chain length and unsaturation ratio, have both been observed to be responsible for the ductility increase, while the higher than room temperature glass transition of PLA and its interesting rigidity were retained. Addition of PHBV to the formulated PLA with oil by-products has also been studied, mainly leading to a significant improvement in the thermomechanical resistance of the material. Scaled-up trials comprising the production of formulated pellets, cast extruded films and their printing using industrial devices were performed. Finally, with the help of the “Laboratoire National de Métrologie et d’Essais” (LNE), the compliance with requirements of Food Contact Material regulation of a formulated film of PLA, as well as its biodegradability according to the EN 13432 standard, have both been proved
Gemili, Seyhun Altınkaya Sacide Alsoy. "Preparation And Characterization of Antimicrobial Polymeric Films For Food Packaging Applications/." [s.l.]: [s.n.], 2007. http://library.iyte.edu.tr/tezler/master/kimyamuh/T000651.pdf.
Повний текст джерелаPungthong, Viriya. "Mechanical properties of polymeric packaging films after radiation sterilization /." Online version of thesis, 1990. http://hdl.handle.net/1850/11179.
Повний текст джерелаMartínez, Abad Antonio. "Development of silver based antimicrobial films for coating and food packaging applications." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/36738.
Повний текст джерелаMartínez Abad, A. (2014). Development of silver based antimicrobial films for coating and food packaging applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/36738
TESIS
Premiado
Al-Ati, Tareq. "Oxygen permeation of virgin HDPE films versus recycled HDPE films /." Online version of thesis, 1994. http://hdl.handle.net/1850/11875.
Повний текст джерелаMuriel, Galet Virginia. "Novel antimicrobial films based on ethylene-vinyl alcohol copolymers for food packaging application." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/48522.
Повний текст джерелаMuriel Galet, V. (2015). Novel antimicrobial films based on ethylene-vinyl alcohol copolymers for food packaging application [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48522
TESIS
Premiado
Baek, Naerin. "Characterization of Hydrophobically Modified Titanium Dioxide Polylactic Acid Nanocomposite Films for Food Packaging Applications." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/82004.
Повний текст джерелаPh. D.
Atik, İsa Doğan Tıhmınlıoğlu Funda. "Preparation And Characterization of Corn Zein Coated Polypropylene (PP) Films For Food Packaging Applications/." [s.l.]: [s.n.], 2007. http://library.iyte.edu.tr/tezler/master/kimyamuh/T000611.pdf.
Повний текст джерелаJohansson, Kristin. "Oxygen-reducing enzymes in coatings and films for active packaging." Doctoral thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-28749.
Повний текст джерелаPizzoli, Ana Paula de Oliveira. "Produção e caracterização de laminados biodegradáveis e antimicrobianos para embalagens de alimentos." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1137.
Повний текст джерелаTendo em vista a crescente demanda por substituição de materiais de embalagens usuais por biodegradáveis bem como pela necessidade da manutenção de segurança dos alimentos durante seu armazenamento, o desenvolvimento de embalagens bioativas biodegradáveis torna-se importante. No presente trabalho foram produzidos laminados compostos por blendas de poli(L-ácido lático) (PLLA), amido termoplástico (TPS) e gelatina por extrusão e calandragem. O processo apresentou-se como uma forma viável para produzir blendas de PLLA / TPS / gelatina com propriedades funcionais interessantes e aspecto homogêneo. A adição de gelatina em diferentes proporções (1, 3 e 5% em relação ao TPS) apresentou diferença significativa nos resultados das análises de solubilidade, permeabilidade ao vapor de água (PVA) e isotermas de sorção de água devido à hidrofilicidade da mesma. Além disso, a incorporação de gelatina na blenda afetou significativamente as propriedades mecânicas através da redução da rigidez associada à incompatibilidade entre PLLA, amido e gelatina, como revelado pelas imagens de microscopia eletrônica de varredura (MEV). Nanopartículas de prata (AgNPs) foram sintetizadas para incorporação aos laminados pela técnica do polissacarídeo modificada, onde nitrato de prata foi reduzido a prata metálica por D-glicose. O diâmetro médio foi determinado através de três técnicas: Espalhamento Dinâmico de Luz (DLS, 63 nm), por Espectrofotômetria UV-Vis (100 nm) e por análise das imagens de MEV (145 nm). Com a análise de FTIR foi possível detectar interações entre os grupamento C=O dos subprodutos de oxidação da D-glicose, produto da reação com o nitrato de prata. As AgNPs apresentaram ação antimicrobiana eficaz contra os microrganismos Bacillus cereus, Staphylococcus aureus, Escherichia coli e Pseudomanas aeruginosa, sendo a Concentração Inibitória Mínima igual a 1,17 µg/ml para E. coli (menor resistência) e 37,50 µg/ml para S. aureus (maior resistência). Os laminados foram tratados superficialmente com a solução resultante da síntese das AgNPs por reticulação enzimática (transglutaminase). Nas imagens de MEV foi possível verificar que os laminados tratados apresentaram maior porosidade em função da umidade promovida pelo tratamento. Através da porosidade criada foram detectadas diferenças significativas nas análises de PVA e propriedades mecânicas. Houve aumento da PVA e redução em todas as propriedades mecânicas, principalmente no módulo de Young em função da criação de pontos de concentração de força. As isotermas apresentaram ajuste adequado ao modelo de GAB (R2>0,99). A atividade antimicrobiana dos laminados contendo AgNPs foi comprovada pela formação de halos de inibição contra os microorganismos descritos anteriormente. Finalmente, os laminados produzidos possuem potencial de aplicação como embalagens ativas com propriedades antimicrobianas e de biodegradação para alimentos.
Due to the growing demand for replacement of the usual packaging materials for biodegradable as well as the need to maintain food safety during storage, the development of bioactive biodegradable packaging becomes important. In this work sheets were produced by extrusion and calendaring process using blends of poly(L-lactic acid) (PLLA), thermoplastic starch (TPS) and gelatin . The process is presented as a viable way to produce blends of PLLA/TPS/gelatin with interesting functional properties and homogeneous appearance. The addition of gelatin in different proportions (1, 3 and 5% related to TPS) showed a significant difference in the solubility test results, the water vapor permeability (WVP) and water sorption isotherms due to gelatin hydrophilicity. Furthermore the incorporation of gelatin in the blend significantly affected the mechanical properties by reducing stiffness associated with incompatibility between PLLA, starch and gelatin, as shown by Scanning Electron Microscopy (SEM) micrographs. Silver nanoparticles (AgNPs) were synthesized for incorporation into the extruded sheets by the modified polysaccharide technique, where silver nitrate is reduced to metallic silver by D-glucose. The average diameter was determined by three techniques: Dynamic light scattering (DLS, 63 nm) by UV-Vis spectrophotometry (100 nm) and by analysis of SEM images (145 nm). With the analysis of FTIR was possible to detect interactions between the C = O groups of D-glucose oxidation byproducts, products of the reaction with silver nitrate. AgNPs presented effective antimicrobial action against the microorganisms: Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, and the Minimum Inhibitory Concentration equal to 1.17 µg/ml for E. coli (lower resistance) and 37.50 µg/ml for S. aureus (greater resistance). The extruded sheets were surface treated with the resulting solution from AgNPs synthesis and enzymatically crosslinked with transglutaminase. At the SEM images it was possible to verify that the treated laminates exhibited higher porosity due to moisture promoted by the treatment. The created porosity influenced significantly the results of the WVP and mechanical properties. There was an increase in vapor permeation and a reduction in all mechanical characteristics, particularly in Young's modulus due to the creation of tension concentration points. The isotherms showed adequate adjustment to GAB model (R2> 0.99). The antimicrobial activity of the laminates containing AgNPs was confirmed by the formation of inhibition zones against the microorganisms described above. Finally, the sheets produced have potential application as active packaging with antimicrobial and biodegradable properties for food.
Tang, Xiaozhi. "Use of extrusion for synthesis of starch-clay nanocomposites for biodegradable packaging films." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/546.
Повний текст джерелаCox, Ryan Yinghua. "Development of a Humidity-Resistant Coating to Impart High Oxygen Barrier Performance to Food Packaging Films." DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1764.
Повний текст джерелаBalaguer, Grimaldo María de la Paz. "Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/48520.
Повний текст джерелаBalaguer Grimaldo, MDLP. (2015). Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48520
TESIS
Premiado
Tampau, Alina. "Carvacrol encapsulation by electrospinning or solvent casting to obtain biodegradable multilayer active films for food packaging applications." Doctoral thesis, Universitat Politècnica de València, 2020. http://hdl.handle.net/10251/140313.
Повний текст джерела[CAT] L'ús massiu de plàstics sintètics i el seu impacte mediambiental obliga a buscar alternatives biodegradables per a l'envasament dels aliments necessari per a la seua conservació.Així mateix,la necessitat d'incrementar la vida útil dels aliments ha despertat gran interés en el desenvolupament de materials actius(antimicrobians i antioxidants)que mantinguen la seua qualitat i seguretat per més temps,per mitjà de l'ús de compostos d'origen natural,segurs per al consumidor.En este sentit,el desenvolupament de materials biodegradables actius per a l'envasament d'aliments constituïx un repte important per a la indústria alimentària.En la present Tesi Doctoral,s'ha estudiat l'encapsulació de carvacrol per mitjà de l'electroestirat o extensió i assecat de diferents dissolucions polimèriques amb carvacrol.S'han utilitzat polímers biodegradables portadors de diferent polaritat(midó termoplàstic:TPS, polivinil-alcohol:PVA, policaprolactona:PCL o àcid poliláctic:PLA)dissolts en el solvent adequat,a fi d'obtindre capes actives.Estes s'han combinat amb altres de polímers amb propietats complementàries,per a obtindre laminats actius adequats per a l'envasament d'aliments.Els laminats van combinar polímers polars(TPS o PVA)i poliésters no polars(PCL o PLA)incorporant el carvacrol en una de les capes.Es va avaluar la cinètica d'alliberament de l'actiu,així com l'acció antimicrobiana dels materials obtinguts.Els laminats es van caracteritzar en la seua funcionalitat com a material d'envàs(propietats de barrera, mecàniques o òptiques),així com en la seua estructura i comportament tèrmic.Els estudis d'encapsulació van revelar un major potencial encapsulant del carvacrol per als polímers no polars(PCL i PLA),encara que el PVA va mostrar també una bona afinitat amb el compost actiu.La matriu de PVA va mostrar una major retenció de carvacrol per mitjà d'electroestirat de les seues dissolucions aquoses que per extensió i assecat,sense necessitat d'addició de tensioactius com el Tween 85.Per a l'encapsulació en PLA,es van usar mescles binàries de solvents aptes per a contacte amb els aliments(acetat d'etil i DMSO).Es va obtindre una major eficiència encapsulant del PLA en els materials obtinguts per extensió i assecat que en els electroestirats.La cinètica d'alliberament del carvacrol de les fibres de PCL va explicar el major efecte antibacterià contra Escherichia coli,i l'escàs efecte antilisteria.La velocitat d'alliberament de l'actiu va augmentar quan va disminuir la polaritat dels simulants alimentaris,mostrant un alliberament complet en els sistemes no polars, però només fins a un 75% en els sistemes aquosos,que requeririen una major proporció de l'actiu en l'envàs per a potenciar la seua efectivitat.La combinació de làmines de TPS amb fibres de PCL carregades amb carvacrol va donar lloc a materials amb una permeabilitat al vapor d'aigua millorada,en comparació amb els films de midó, sense efectes rellevants sobre les altres propietats funcionals.Quan els laminats es van provar in vitro contra ceps Gram(+) i Gram(-) van mostrar un efecte antibacterià semblant al de les fibres de PCL amb carvacrol,però retardat en el temps.Els estudis de desintegració-biodegradació dels laminats midó-PCL van revelar que les pel·lícules amb carvacrol van afectar l'activitat de l'inocule del compost,disminuint lleugerament la biodegradabilitat,però aconseguint valors de desintegració semblants(75-80%)a les mostres lliures de carvacrol.Es van obtindre també laminats de PLA i PVA per mitjà de l'extensió i assecat de dissolucions aquoses de PVA amb carvacrol.La superfície del PLA va ser sotmesa a aminolizatció a fi de millorar l'extensibilitat de les dissolucions aquoses.A pesar de l'increment de la component polar de l'energia superficial del PLA i la seua millorada mullabilitat amb les solucions de PVA,estes bicapes no van mostrar una millora significativa en les propietats mecàniques i de barrera
[EN] The massive use of synthetic plastics and their environmental impact makes necessary the search for biodegradable alternatives for food packaging. Likewise, the need to increase the shelf life of food has aroused great interest in the development of active materials (antimicrobial and antioxidant) that maintain food quality and safety for longer periods of time through the use of compounds of natural origin, safe for the consumer. In this sense, the development of active biodegradable materials for food packaging is both a major imperative and challenge for the food industry today. In the present Doctoral Thesis, the encapsulation of carvacrol has been studied by means of the electrospinning or casting of different polymeric solutions with carvacrol. Biodegradable polymers with different polarities (thermoplastic starch: TPS, poly(vinyl-alcohol): PVA, poly-(¿-caprolactone): PCL or poly(lactic acid): PLA) dissolved in the appropriate solvent have been used to obtain active layers. These have been combined with other polymers with complementary properties, to obtain active laminates suitable for food packaging. The laminates combined polar polymers (TPS or PVA) and non-polar polyesters (PCL or PLA) incorporating carvacrol in one of the layers. The release kinetics of the active ingredient was evaluated, as well as the antimicrobial action of the materials obtained. The laminates were characterized in their functionality as a packaging material (barrier, mechanical or optical properties), as well as in their structure and thermal behaviour. Encapsulation studies revealed a higher encapsulating potential of carvacrol for non-polar polymers (PCL and PLA), although PVA also showed a good affinity with the active compound. The PVA matrix showed a higher retention of carvacrol by electrospinning of its aqueous solutions than by casting, without the need for addition of surfactants such as Tween 85. For the encapsulation in PLA, binary mixtures of solvents suitable for food contact (ethyl acetate and DMSO) were used. A higher encapsulation efficiency of PLA was obtained in the materials produced by casting than by electrospinning. The carvacrol release kinetics of PCL fibres explained the higher antibacterial effect against Escherichia coli and the lower antilisterial effect. The release ratio of the active ingredient increased when the polarity of the food simulants decreased, showing a complete release in non-polar systems and only up to 75% in aqueous systems that would require a higher proportion of the active ingredient in the packaging material to enhance its effectiveness. The combination of TPS films with carvacrol loaded PCL fibres resulted in materials with improved water vapour permeabilities, compared to starch films, with no relevant effects on the other functional properties. When the laminates were tested in vitro against Gram (+) and Gram (-) strains, they showed a similar antibacterial effect to that of PCL fibres with carvacrol, but delayed in time. Disintegration-biodegradation studies of PCL-starch laminates revealed that carvacrol films affected the activity of the compost inoculum, slightly decreasing the biodegradability of the laminates, but reaching similar disintegration values (75-80%) to the carvacrol-free samples. PLA and PVA laminates were also obtained by casting aqueous PVA solutions with carvacrol. The surface of PLA was submitted to aminolization in order to improve the extensibility of the aqueous solutions. Despite the increase in the polar component of the PLA surface energy and its improved wettability with PVA solutions, these bilayers did not show significant improvement in mechanical and barrier properties over the PLA monolayers.
The authors would like to thank the Ministerio de Economia y Competitividad of Spain, for funding this study as part of projects AGL2013-42989-R and AGL2016-76699-R and predoctoral research grant # BES-2014-068100.
Tampau, A. (2020). Carvacrol encapsulation by electrospinning or solvent casting to obtain biodegradable multilayer active films for food packaging applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/140313
TESIS
Yoo, SeungRan. "The effect of high pressure processing on the mass transfer of Irganox 1076 in low-density polyethylene films and in 95% ethanol as a food simulant." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1181749497.
Повний текст джерелаRodrigues, Delane da Costa. "INFLUÃNCIA DE AMIDO DE MANDIOCA E CERA DE CARNAÃBA SOBRE AS PROPRIEDADES FÃSICAS DE FILME Ã BASE DE GOMA DE CAJUEIRO." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8462.
Повний текст джерелаThe search for new packaging materials to keep or even improve food quality, at the same time reducing generation of nonbiodegradable waste, has motivated the exploitation of edible and/or biodegradable materials based on renewable resources. Film formation requires the presence of a component which forms a continuous and cohesive matrix. Starch has such a property and, being abundant and relatively cheap, is an interesting material for film formation. Cashew tree gum is a complex polysaccharide whose film forming properties are still poorly exploited. Polysaccharides such as starch and cashew tree gum, due to their high polarity, have good barrier to oxygen (O2) and carbon dioxide (CO2), but high water vapor permeability. The incorporation of hydrophobic components such as waxes to polysaccharide-based films improves their barrier to water vapor. The main objective of this study was to develop composite edible films based on starch, cashew tree gum and carnauba wax. A mixture (simplex centroid) design generated 10 treatments with the following proportions (on a weight basis): starch, 15 to 30%; cashew tree gum, 75 to 85%; and carnauba wax, 0 to 15%. In order to check the temperature used is sufficient had occurred to starch gelatinization, one ray diffraction analysis - x (X-DR) were performed. The film characterization was based on the following analyses: tensile properties (tensile strength - TS, elongation at break - EB, elastic modulus- EM), opacity (OP), water solubility (SOL), water vapor permeability (WVP) and glass transition temperature (Tg). The relative starch:cashew tree gum proportions did not significantly affect the overall film properties. Incorporation of carnauba wax reduced water solubility and water vapor permeability, since it decreased the hydrophilic content of the films. On the other hand, carnauba wax increased the film opacity and reduced their tensile strength and elastic modulus. For elongation at break, the influence of carnauba wax was the opposite, i.e., the property was favored by the wax. The presence of wax in the film promoted the onset of endothermic peaks in the curve of heat flow. However, the films without hydrophobic content, endothermic peaks were not observed, thus we can conclude that there was an interaction between the materials used.
Richter, Kevin. "Effect of concentration of glutaraldehyde and glyoxal on binding lysozyme to zein based films to control foodborne pathogens in tomatoes." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/41893.
Повний текст джерелаMaster of Science
Essabti, Fatima. "Mise en œuvre de nanocomposites à matrice chitosane pour renforcer l’imperméabilité aux gaz de films d’emballage alimentaire." Thesis, Paris, ENSAM, 2018. http://www.theses.fr/2018ENAM0059/document.
Повний текст джерелаIn order to protect food, the packaging industry performs a film coating with a very thin polymer layer to increase its gas barrier properties. The major problem of these coatings is that they are generally made of poly(vinylidene chloride) which leads to a toxic gas production during incineration. In view of the rapid change of the global environmental restrictions that become quite stringent, bioplastics seem promising alternatives. In this context, this thesis deals with a fundamental study of poly(ethylene terephthalate) films coated with a polysaccharide: chitosan. Chitosan offers good barrier properties in dry conditions. However, its application in the packaging is limited because of its hydrophilic character. Therefore, the main goal of our work is on one hand to enhance the dry barrier properties of the material through adding nanoclays and on the other hand to improve its resistance to moisture by incorporating palmitic acid by grafting it to the chitosane backbone. The incorporation efficiency of vermiculite was confirmed by DLS, DVS and XRD. A barrier improvement factor (BiF) of about 100 for helium and more than 10 for dioxygen with the addition of 50% vermiculite was obtained under dry conditions. The grafting of palmitic acid has been confirmed by FTIR spectroscopy, ATG, DSC and RMN. The results of helium permeability measurements showed an improvement of the barrier factor (BIF) of 2 in the case of a chitosan-grafted-palmitic acid layer with 60 weight% of vermiculite compared to the uncoated PET at 98% RH
Pinto, AlaÃdes Maria Borba. "Desenvolvimento de filmes e revestimentos biodegradÃveis à base de amido, goma de cajueiro e montmorilonita." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9184.
Повний текст джерелаO objetivo desse trabalho foi desenvolver filmes biodegradÃveis à base de amido e goma de cajueiro, acrescidos ou nÃo de montmorilonita. Em uma primeira etapa, foi feito um delineamento experimental composto central a partir de misturas entre amido e goma de cajueiro (1:1, m:m) adicionadas de diferentes concentraÃÃes da argila montmorilonita (0 a 15% - MMT) e tempos de ultrassom (0 a 5 min), onde foi realizado um estudo das variaÃÃes de desempenho de filmes produzidos por deposiÃÃo (casting), em funÃÃo das variÃveis. Os filmes foram avaliados em termos de propriedades Ãticas, mecÃnicas, de barreira e tÃrmicas e analisados por Microscopia eletrÃnica de varredura (MEV) e Ãngulo de contato. Em uma segunda etapa do trabalho, as formulaÃÃes dos filmes amido e goma de cajueiro (AGC) e os de amido, goma de cajueiro e montmorilonita AGC-MMT foram testadas como revestimentos para amÃndoas de castanhas de caju. As amÃndoas revestidas com AGC e AGC-MMT, assim como um controle (amÃndoas sem revestimento), foram acondicionadas em sacos plÃsticos de polietileno de baixa densidade, estocadas em temperatura e umidade ambiente e tiveram sua estabilidade avaliada. Os testes de estabilidade realizados foram baseados em medidas de absorÃÃo de umidade, atividade de Ãgua e do grau de oxidaÃÃo das amÃndoas (determinado por Ãndice de perÃxido e Ãndice de acidez). O incremento de MMT interferiu nas propriedades Ãticas dos filmes, aumentando sua opacidade. A permeabilidade ao vapor de Ãgua dos filmes produzidos foi significativamente (p < 0,05) reduzida pela MMT. A resistÃncia à traÃÃo e o mÃdulo elÃstico apresentaram valores mÃximos em uma faixa intermediÃria de concentraÃÃo de MMT. O tempo de ultrassom favoreceu a dispersÃo da argila em concentraÃÃes baixas de MMT, porÃm em concentraÃÃes maiores favorece a formaÃÃo de aglomerados, o que tambÃm à visualizado nas micrografias obtidas por MEV. Com o aumento do tempo de ultrassom, a resistÃncia à traÃÃo e o mÃdulo tenderam a aumentar. As curvas de DSC do amido, goma de cajueiro e do filme produzido sem MMT apresentaram picos endotÃrmicos similares em torno de 110ÂC, que podem estar relacionados à superposiÃÃo de eventos como vaporizaÃÃo da Ãgua e fusÃo da fase cristalina dos componentes. A medida do Ãngulo de contato comprovou que os filmes produzidos sÃo altamente hidrofÃlicos. Os testes de estabilidade realizados mostram que os revestimentos AGC e AGC-MMT conferem menor acidez e Ãndice de perÃxidos quando comparados a um controle podendo ser uma alternativa para aumento da vida de prateleira das amÃndoas de castanhas de caju, servindo como embalagem primÃria.
The purpose of this study was to develop biodegradable films based on starch and cashew gum, added or not with montmorillonite. At a first stage, a central composite experimental design was carried out from mixtures of starch and cashew gum (1:1, m: m) added with different concentrations of montmorillonite (0-15% - MMT) and submitted to variable ultrasound times (0-5 min), In a study of variations in the performance of films produced by casting. The films were evaluated in terms of optical properties, mechanical, barrier and thermal. As well as scanning electron microscopy (SEM) and contact angle. In a second stage of the work, the formulations of the films based on starch and cashew tree gum (SCG) and starch cashew tree gum and montmorillonite (SCG-MMT) were tested as coatings for cashew kernels. The kernels coated with SCG and SCG-MMT, as a control (uncoated kernels) were placed in plastic bags of low density polyethylene, stored at room temperature and relative humidity and their stability were evaluated. Stability tests were based on measurements of moisture absorption, water activity and the degree of oxidation of almonds (determined by peroxide value and acid value). The increase of MMT concentration interfered with the optical properties of the films, increasing its opacity. The water vapor permeability of films was significantly (p <0.05) reduced by the MMT. The tensile strength and elastic modulus showed a peak in an intermediate range of concentration of MMT. The time of ultrasound favors the dispersion of clay in low concentrations of MMT, but at higher concentrations et led to formation of agglomerates, which also appeared in SEM micrographs. With the increase of ultrasound times tensile strength and modulus tended to increase. DSC curves of starch, cashew gum and the film produced without MMT the endothermic peaks had similar MMT about 110 Â C, that may be related superposition events such as the vaporization of water and melting of the crystalline phase of the components. The contact angle measurement showed that the films are highly hydrophilic. Stability tests performed show that the coatings AG and AG-MMT give less acidity and peroxide value when compared to a control, may be an alternative of the use to increase the shelf life of almonds cashew nuts serving as primary packaging.
Arding, Fredrik. "Sensory evaluation and quality assessment of an alternative inner coating film in yogurt cartons." Thesis, Linköpings universitet, Teknisk biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119767.
Повний текст джерелаKechichian, Viviane. "Adição de ingredientes antimicrobianos em filmes biodegradáveis à base de fécula de mandioca." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-13082007-155057/.
Повний текст джерелаIn this work, natural antimicrobial ingredients were added to biodegradable film (biofilm) based on cassava starch with sucrose and inverted sugar as plasticizers. The selection of the antimicrobial ingredients (clove powder, cinnamon powder, red pepper powder, orange essencial oil, coffee powder, honey and propolis extract) was carried out applying an experimental design (incomplete factorial 27-3) and the barrier properties (water vapour permeability and water vapour permeability rate) and mechanical properties (tensile strength and elongation at break) of the biofilms were determined. The biofilms presented lower data regarding mechanical properties when compared to biofilm control. In general, the water vapour permeability rate of the antimicrobial biofilms was statistically equal to the control. In the second phase of the work, the optimization of the selected ingredients was carried out applying an experimental design, with the addition of only clove and cinnamon powder due to the fact that they showed the most promissing results at the previous phase. The addition of clove and cinnamon powder modified the mechanical properties but the modifications resulted by the addition of cinnamon powder were less intense tha n the ones resulted by the addition of clove powder, which can be justified by the particle size differences between them. The water vapour permeability rate decreased by specific ingredients concentration (0.34% for the cinnamon in powder and 0.20% for the clove in powder). The biofilms antimicrobial effect was investigated as packaging of pan bread slices and it was verified that the biofilms water activity increased after 7 days of contact. Probably, the biofilms became suitable substrates for yeast and mold development due to the fact that these microorganisms grew equally or more intensely in the pan bread slices when the biofilms were present in comparison to the cases of its absence. According to the results, it is not possible to evaluate clearly the antimicrobial effect of the added ingredients to the biofilm matrix against yeast and mold development in pan bread slices.
Olabarrieta, Idoia. "Strategies to improve the aging, barrier and mechanical properties of chitosan, whey and wheat gluten protein films." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-208.
Повний текст джерелаMOURA, ESPERIDIANA A. B. de. "Avaliação do desempenho de embalagens para alimentos quando submetidas a tratamento por radiação ionizante." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11427.
Повний текст джерелаMade available in DSpace on 2014-10-09T14:08:50Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Moura, Esperidiana Augusta Barretos de. "Avaliação do desempenho de embalagens para alimentos quando submetidas a tratamento por radiação ionizante." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-22032012-172658/.
Повний текст джерелаIn this study the mechanical properties (tensile strength and percentage elongation at break and penetration resistance), optical properties, gas oxygen and water vapor permeability, the overall migration tests into aqueous food simulant (3% aqueous acetic acid) and fatty food simulant (n-heptane), as well as the formation of volatile radiation product tests were used to evaluate the effects of ionizing radiation (gamma irradiation or electron-beam irradiation) on commercial monolayer and multilayer flexible plastics packaging materials. These films are two typical materials produced in Brazil for industrial meat packaging, one of them is a monolayer low-density polyethylene (LDPE) and other is a multilayer co extruded low-density polyethylene (LDPE), ethylene vinyl alcohol (EVOH), polyamide (PA) based film (LDPE/EVOH/PA). Film samples were irradiated with doses up to 30 kGy, at room temperature and in the presence of air with gamma rays using a 60Co facility and electron beam from 1.5 MeV electrostatic accelerator. Alterations of these properties were detected according to the dose applied initially eight day after irradiation took place and new alterations of these values when the properties were evaluate two to three months after irradiation process. The results showed that scission reactions are higher than cross-linking process for both studied films, irradiated with gamma rays and electron beam. The evaluated properties of the irradiated films were not affected significantly with the dose range and period studied. The monolayer Unipac PE-60 and the multilayer Lovaflex CH 130 films can be used as food packaging materials for food pasteurization and in the sterilization process of by ionizing radiation using a gamma facilities and electron beam accelerators in commercial scale.
Chacko, Jino. "Controlled release of Nisin from a biopolymer based film for food packaging applications." 2008. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2515/index.html.
Повний текст джерелаMistry, Yogesh. "Development of LDPE-based antimicrobial films for food packaging." Thesis, 2006. https://vuir.vu.edu.au/1485/.
Повний текст джерелаSaberi, Bahareh. "Evaluation of edible coating application on ‘Valencia’ orange fruit." Thesis, 2018. http://hdl.handle.net/1959.13/1406382.
Повний текст джерелаThe continuous increase of consumer interest in higher quality food, in combination with the ecological and economic requirements to decrease disposal of post-user waste, has induced increasing attention to research into edible films and coatings. As a replacement to more traditional recycling procedures, edible and biodegradable polymers, that can be reverted to the biological cycle after use, have emerged. Consequently, the use of biodegradable agricultural polymers would not only resolve the environmental problems, but also present a potential new use for extra farm produce. Such films can mechanically protect foods, inhibit the contamination from microorganisms, and preserve quality loss of foods caused by mass transfer (e.g. moisture, gases, flavors, etc.). Additionally, edible films and coatings can be applied as a carrier for incorporating natural or chemical antimicrobial agents, antioxidants, enzymes or functional components such as probiotics, minerals and vitamins. The application of edible films and coatings has been studied as a good alternative for the conservation of intact, and fresh fruit and vegetables. Fruit and vegetables consist of living tissue which undergoes many physical and chemical changes due to deteriorative and synthetic biochemical processes, such as enhanced ethylene production and respiration rate, as well as consumption of sugars, lipids and organic acids accelerating the ripening process. Therefore the quality of products can be affected including flavor, textural, nutritional, and pigmentation changes during storage. The major purpose of employing edible films and coatings is to act as a semipermeable membrane against gases and vapor that preserves the produce and reduces the rate of physiological postharvest degradation; however, they can also carry additives, for example texture enhancers, antimicrobials, and antioxidants to extend the shelf life of produce after harvest. Edible films can be prepared from proteins, polysaccharides, lipids or a combination of these constituents. Starch can be used for edible films production because it can be obtained from a large number of raw materials and is a renewable and biodegradable biopolymer. Pea starch has been demonstrated to produce the films with improved physical and mechanical properties in comparison with films prepared from other starches due to high amount of amylose. The development of pea starch film with improved functions affects its application. Hypothesis and Aims: In the current study, we hypothesized that development of novel edible films made of pea starch will be an improved alternative to substitute the common commercial waxes used for coating in the citrus industry for extending the orange fruit shelf-life. The optimized formulations of pea starch and other ingredients used to improve the physical, mechanical and barrier properties of films will maintain physical, sensorial and quality properties of the fruit during simulated commercial storage conditions. Overall, the aims of this study were: Aim 1: To develop pea starch films: (A) To determine the moisture barrier, color, mechanical, and structural properties of pea starch film affected by different concentrations of glycerol as plasticizer and environmental relative humidity (RH). (B) To develop a new type of edible film made of pea starch and guar gum in the presence of glycerol, and to examine the mechanical and water barrier properties of the resulting composite films as a function of guar gum and glycerol concentrations using a mixture experimental design. (C) To study the influence of different plasticizers (glycols, sugars and polyols) on the moisture sorption, mechanical, physical, optical, and microstructure characteristics of pea starch-guar gum (PSGG) film. (D) To investigate the alteration of physical, barrier and mechanical properties of PSGG films resulting from the incorporation of hydrophobic compounds such as shellac, emulsifier, and surfactant using response surface methodology. Aim 2: To evaluate the potential of application of films obtained from Aim 1 on ‘Valencia’ orange fruit: (A) To determine whether films have the potential to be used as an edible coating for increasing the shelf life of ‘Valencia’ orange whilst maintaining the quality of fruit during storage. The effectiveness of the best coatings formulation on gas exchange, vitamin C, total phenolic compounds, antioxidant capacity, and sensory quality of fruit were evaluated. Results: The results showed that increasing the concentration of glycerol led to improvement of the tensile strength of the pea starch films at RH < 43 %, the percent elongation as well as the deformation at break at RH < 84 %. Increasing plasticizer content and RH also resulted in films with lower Young’s modulus, lower puncture force, but higher puncture deformation. Furthermore, increasing plasticizer content led to the films with a more opaque appearance. Pea starch films prepared with 15 and 25 % glycerol had lower water vapor permeability in comparison with un-plasticized film indicating its potential application as edible films in the food and pharmaceutical industries. The physical, optical, mechanical and barrier properties of pea starch edible films were improved by optimizing concentrations of pea starch (2-3 g), guar gum (0.1-0.5 g) and glycerol (15-35%) by using Box–Behnken response surface design (BBD). The results revealed that increasing pea starch and guar gum content favored formation of a more resistant polymeric structure. The optimized conditions with the goal of maximizing optical and mechanical properties and minimizing water vapor permeability, moisture content, solubility and color were 2.5 g pea starch, 0.3 g guar gum and 25 % (w/w) glycerol based on the dry film matter in 100 mL of distilled water. The addition of various plasticizers to the PSGG film showed that the films containing plasticizers with higher functional groups had lower equilibrium moisture content at aw < 0.4. In general, a reduction in tensile strength and Young's modulus and an increase in elongation at break were detected when the molecular weight of plasticizers and relative humidity increased in all film formulations. Films plasticized with monosaccharide showed similar mechanical properties to those with sorbitol, but lower solubility and water vapor permeability (WVP), higher transparency and moisture content than the sorbitol-plasticized films. The most noticeable plasticization effect was exerted in the following order: glycerol > EG > PG > xylitol > fructose > sorbitol > mannitol > galactose > glucose > sucrose > maltitol. The incorporation of shellac as the hydrophobic compound in the PSGG film plasticized with glycerol led to a slightly increased film thickness. However, the addition of higher concentrations of shellac did not improve the moisture barrier of PSGG film owing to the poor distribution of shellac in the film structure. Film formulated with 40 % shellac, 1 % SA, and 0.3 % Tween-20 exhibited optimal functional properties. Moreover, films containing oleic acid (OA) showed not only lower thickness, WVP, moisture content, and water solubility, but also higher percentage of elongation (E), tensile strength (TS), and transparency compared with other fatty acids tested. Biocomposite pea starch-guar gum-shellac (PSGG-Sh) film containing OA was considered for the coating of oranges. The incorporation of lipid compounds into the PSGG coatings (PSGG-Sh) generally resulted in the best performance in reducing fruit respiration rate, ethylene production, weight and firmness loss, peel pitting, and fruit decay rate of the coated oranges. Fruit coated with PSGG-Sh and a single layer of PSGG coatings generally resulted in higher scores for overall flavor and freshness after four weeks at 5 °C followed by one week at 20 °C, than uncoated fruit, as assessed by a sensory panel. Overall results suggested that PSGG-based edible coatings could be a beneficial substitute to common commercial waxes for maintaining quality and storability, as well as extending shelf life of citrus fruit and potentially other fresh horticultural produce. Conclusions: In conclusion, the hypothesis was supported and the aims were addressed. This study revealed that pea starch can be used to produce films with appropriate physical and mechanical properties in the presence of guar gum, various plasticizers (polyols, glycols and sugars), and hydrophobic compounds. Application of PSGG edible coatings incorporated with shellac showed great potential for preservation quality, storability and improved shelf life of ‘Valencia’ oranges at 5 °C and 20 °C. The results of this study can be further utilized for formation of biodegradable films or edible coatings and better understanding of using pea starch in the food packaging industry. The results also suggested that PSGG-based edible coatings could be a beneficial substitute to common commercial waxes for maintaining quality and extending shelf life of citrus fruit and potentially other fresh horticultural produce.
Chih-Shun, Chen, and 陳志順. "Characterization of Commonly Used Food Packaging Films." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/78965404581927254883.
Повний текст джерела萬能科技大學
材料科技研究所
100
We used polyurethane, ethyl acetate, and commonly used food packing films to prepare lamination films. After laminating, the lamination film was dried and cured in a oven at 50℃ for aging. The lamination films possessed thermal, mechanical, and anti-moisture-penetrability properties, which is suitable for food packing materials. The structure of the films was characterized by FTIR. The thermal properties of the film were measured by TGA and DSC. The anti-penetration strength was used by an Instron. The water vapor transmission rate of the films was measured with a water vapor transmission machine. Mechanical analysis showed that the lamination films have different properties, due to the composition and the lamination order in the films. The lamination films have good thermal properties, due to the addition of polyurethane and the combination of various films. PET and ALOPET showed different thermal properties, due to the different component in the film. The hydrophobic property of the single film was measured by contact angle. Surface treatment on the film showed the improved hydrophilic properties, which is favor for printing and combination. For water vapor transmission rate analysis, the lamination films can reduce the rate of water vapor transmission. These studies revealed that the lamination films improve the anti-penetration strength, water vapor penetration rate, and thermal properties.
Ferreira, Ana Rita Vasques. "Design of microbial polysaccharide films for food packaging." Doctoral thesis, 2016. http://hdl.handle.net/10362/19886.
Повний текст джерелаLang, Jillian C. "Tocopherol stability in controlled release packaging films." 2009. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051028.
Повний текст джерелаSalvada, Joana Sanches. "Development of arabinoxylans-based composite films for food packaging." Master's thesis, 2022. http://hdl.handle.net/10362/133790.
Повний текст джерелаNas últimas décadas, o uso excessivo de polímeros sintéticos na indústria das embalagens de plástico, tornou-se um grave problema ambiental a nível global devido à sua falta de biodegradabilidade. Para ultrapassar este problema, as indústrias e os investigadores têm vindo a unir esforços para diminuir a quantidade de materiais sintéticos usados, explorando alternativas obtidas a partir de fontes renováveis, de modo a desenvolver embalagens biodegradáveis e biocompatíveis. Neste contexto, filmes e revestimentos comestíveis baseados em biopolímeros biodegradáveis têm ganho uma importância significativa por apresentarem uma solução promissora para o problema que enfrentamos. Nesta tese, o polissacárido arabinoxilano, extraído da fibra do milho por hidrólise alcalina, foi usado para produzir filmes comestíveis compósito e multicamada. Os filmes compósito foram produzidos através de uma emulsão óleo-em-água com diferentes quantidades de ácido oleico ou limoneno, enquanto que os filmes multicamada resultaram da submersão dos filmes de arabinoxilano numa solução de cera de abelha. Ambos, em conjunto com os filmes de arabinoxilano puros, foram de seguida caraterizados em termos da sua atividade antioxidante, das suas propriedades óticas e mecânicas, hidrofobicidade superficial, e propriedades de barreira contra o vapor de água e radiação Ultravioleta-Visível (UV-Vis). Os filmes produzidos a partir de emulsões resultantes eram heterogéneos e espessos, apresentando piores resultados ao nível de permeabilidade ao vapor de água e de hidrofobicidade de superfície, além de menor atividade antioxidante em comparação com os filmes de arabinoxilano puros. Por outro lado, os filmes multicamada revelaram um revestimento de cera de abelha liso e uniforme, melhorando as suas propriedades de barreira contra o vapor de água e a radiação UV-Vis. Adicionalmente, estes filmes demonstraram valores mais elevados de ângulo de contacto com a água, tensão de stress e módulo de Young, mas valores de deformação mais baixos, em comparação com os filmes compósito. Os resultados sugerem que os filmes multicamada são mais vantajosos do que os filmes produzidos a partir de emulsões. Sendo assim, a produção dos filmes biopoliméricos desenvolvidos irá ter um resultado positivo, contribuindo para melhorar as práticas sustentáveis no setor das embalagens para alimentos.
Mistry, Yogesh. "Development of LDPE-based antimicrobial films for food packaging." 2006. http://eprints.vu.edu.au/1485/1/Mistry.pdf.
Повний текст джерелаTello-Lopez, Edgar Eduardo. "Improved moisture permeability determinations for packaging films and food coatings." Thesis, 1994. http://hdl.handle.net/1957/27233.
Повний текст джерелаGraduation date: 1994
Suppakul, Panuwat. "Study of antimicrobial polymeric packaging films containing basil extracts." Thesis, 2004. https://vuir.vu.edu.au/15423/.
Повний текст джерелаWeng, Verónica Lee. "Corn arabinoxylan biopolymers as materials for biodegradable films for food packaging." Master's thesis, 2020. http://hdl.handle.net/10362/109081.
Повний текст джерелаshu-chuan, Chang, and 張淑娟. "Preparation and characterization of biodegradable food packaging films containing cellulose and zein." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/78468318562725186193.
Повний текст джерела大葉大學
食品工程研究所
86
Development and use of biodegradable food packaging films insubstitution of petroleum plastic films is an urgent issue attracting theworldwide concern based on the consideration of environmental protec-tion.In general, cellulose-based films are hydrophilic and hygroscopic, whilezein films are hydrophobic and fragile. In this study, a goal was pursued tocombine the beneficial properties of cellulose and zein to comprise asuitable formulation to prepare biodegradable packaging films.Hydroxylpropyl me thyl cellulose ( HPMC ), methyl cellulose ( MC ) andzein were used. The plasticizer effect of polyethylene glycol ( PEG ) wasintensively investigated. A dynamic mechanical analyzer ( DMA ) wasmonitored to analyze the mechanical properties of the prepared films.Elongation ( or strain ), toughness and tensile strength ( or stress )of HPMC and HPMC/MC films decreased while hardness ( modulus ) increasedwith the increase of zein concentration. On the same basis of zeinconcentration, elongation and hardness of H PMC/MC films are higher thanHPMC films while tan d of HPMC/MC films increased with the increase of zeinconcentration. In comparison, HPMC films were more elastic than HPMC/MCfilms. As a general trend, both HPMC and HPMC/MC films increased theirhard-ness and brittleness as zein concentraion increased. When PEG wasadded, elongation of HPMC and HPMC/MC films increased while hardnessdecreased with increase of PEG addition. The toughness of HPMC films alsoincreased as the concentration of the added PEG in -creased. Tan d and Tg ofHPMC and HPMC/MC films decreased with increase of PEG addition and thisindicates that elasticity of the films increased with increase of PEGaddition. Water vapor permeability ( WVP ) of HPMC and HPMC/MC filmsdecreased as the concentration of zein increased. On the same basis of zeinconcentration, WVP of HPMC films decreased with an increase of PEG addition.When PEG was added at 1.0 % for HPMC/MC films, the lowest WVP was obtained.In the aspect of oxygen barrier of the films in relation to peanut oiloxi-dation, oxidation retardation of the HPMC and HPMC/MC films in-creasedwith increase of zein concentration. When PEG was added, the most effectiveoxygen barrier in prevention of oil oxidation was ob-tained at 1.0 % PEG forHPMC films containing 2.0 % zein and 0.5 % PEG for HPMC/MC films containing1.0 % zein.
Al-Nasiri, Ghofran. "Microencapsulation of Natural Antimicrobial Agents to Minimize Loss from Food Packaging Films." Thesis, 2019. https://vuir.vu.edu.au/40070/.
Повний текст джерелаSedayu, Bakti B. "Development of Semi-Refined k-Carrageenan-Based Films for Food Packaging Applications." Thesis, 2020. https://vuir.vu.edu.au/40249/.
Повний текст джерелаAttianese, Ilaria. "Development of new material formulations to produce active films for food packaging." Tesi di dottorato, 2013. http://www.fedoa.unina.it/9523/1/Attianese_Ilaria_25.pdf.
Повний текст джерела