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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Adequações tecnicas de um sistema asseptico para leite e bebidas de alta acidez em embalagens flexiveis / Technical evaluation of an aseptic system for milk and high acid beverages in flexible pouches

Walter, Eduardo Henrique Miranda 02 November 2010 (has links)
Orientador: Jose de Assis Fonseca Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-15T08:14:09Z (GMT). No. of bitstreams: 1 Walter_EduardoHenriqueMiranda_D.pdf: 5634901 bytes, checksum: 43f060f6a152462fae06f4a9bd631c70 (MD5) Previous issue date: 2010 / Resumo: Os sistemas assepticos sao uma das tecnologias mais empregadas na conservacao de bebidas a temperatura ambiente, compondo um mercado dinamico e promissor de produtos, embalagens e equipamentos. O objetivo desse trabalho foi avaliar um sistema asseptico projetado para produzir 1.000 L/h de leite longa vida e bebidas de alta acidez (dois tipos de chas e quatro refrescos mistos de maca, pera e pessego), com uma taxa de defeitos de 0,1%. As embalagens consistiram em bolsas flexiveis com termossoldagem tipo almofada de polietileno de baixa densidade pigmentado de branco com dioxido de titanio, tradicionalmente utilizado para leite pasteurizado, e laminado multicamada com propriedades de barreira ao oxigenio e a luz. Foram realizadas 15 producoes de leite longa vida e quatro das bebidas de alta acidez. Os testes foram conduzidos num sistema composto por equipamentos comerciais (tanques, bombas, valvulas, tubulacoes e trocador de calor) e em desenvolvimento (tanque de produto e maquina de embalagem tipo forma, enche e fecha), todos destinados as industrias de pequena escala de producao. O sistema foi avaliado com base em testes de esterilizacao comercial e analises de aceitacao sensorial dos produtos. A taxa de defeitos nas producoes de leite longa vida ficou na ordem de 2%, enquanto para as bebidas de alta acidez de 0,4%. A aceitacao sensorial do leite longa vida nas embalagens de polietileno, estocadas no escuro, variou entre quatro e sete semanas, de acordo com a qualidade da materia-prima, enquanto a aceitacao sensorial do produto exposto a luz foi de alguns dias. Na embalagem laminada, a luz nao afetou a estabilidade do produto, que teve uma vida de prateleira entre 12 e 24 semanas, dependendo da materia-prima. Esses resultados comprovaram a viabilidade das embalagens para a conservacao do produto. Entretanto, o sistema devera passar por melhorias, alcancando desse modo o potencial para aplicacao em industrias de pequena escala de producao. A simplicidade da linha de processamento e embalagem contribuiu para quebrar o paradigma de que os sistemas assepticos tem de ser sofisticados e onerosos / Abstract: Aseptic systems are one of the main technologies employed for shelf stable milk and juices, creating a dynamic and promising market for products, packaging and equipments. The aim of this study was to evaluate an aseptic system designed to produce 1000 L/h long-life milk and high acidity soft drinks (two teas and four soft drinks, mixed with apple, pear and peach), with a defect rate of 0.1 %. The packages were pillow-style pouches of low density polyethylene pigmented white with titanium dioxide, traditionally used for packaging pasteurized milk in Brazil, and multilayer laminate with oxygen and light barrier properties. There were performed 15 trials of long-life milk and four of soft drinks. Tests were conducted in the system composed of commercial equipment (tanks, pumps, valves, piping and heat exchanger), product tank, and form/fill/seal packaging machine, all used to small-scale production. The system evaluation was based on tests for commercial sterility and sensory acceptability testing of the products. The defect rate in the production of long-life milk was around 2%, while in high acidity drinks of 0.4%. The sensory acceptability of long-life milk in polyethylene containers, stored in the dark, ranged from four to seven weeks, according to the quality of raw material, while for the products exposed to light, it was of a few days. In the laminated bag, light did not affect the stability of the product, which had a shelf life ranged from 12 to 24 weeks, depending on the raw material used. These results have proved the feasibility of both packs for the conservation of the product. However, the system must go through improvements, thereby achieving the potential for application in small-scale industries. The simplicity of the processing and packaging system helped to break the paradigm that aseptic systems have to be sophisticated and expensive / Doutorado / Doutor em Tecnologia de Alimentos
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Problematika septických stavů na jednotce intenzivní péče / Problem of sepsis in the intensive care unit

Škrabánková, Hana January 2014 (has links)
The aim of the thesis was to determine the microbial colonization at the injection site of central venous catheter and its possible influence to maintain the lowest incidence of catheter sepsis. The culture results of skin swabs and taken blood cultures from two groups of patients were compared with each other using qualitative analysis methods. Those were Intensive Care Unit patients with established central venous catheter. The result was the discovery of microbial colonization of the skin and the representation of different pathogenic strains at the site of a central venous catheter for both established groups. Further showed that the higher the risk of microbial colonization with symptoms of catheter sepsis was seen where patients have central venous catheter established for longer period of time and have been treated under home parental nutrition program with stoma. The recommendation is the continuous education of health professionals to act in accordance with the latest preventive treatment recommendations, and the emphasis is mainly placed on hands cleaning and disinfecting as the hands of health professionals are one of the most common and risky way of transmission of pathogenic strains with potential nosocomial infection formation. Aseptic principles must be repeatedly communicated to all...
33

Proteomic and Lipidomic Analysis of Mycobacteriophages Zalkecks and PotatoSplit

Taylor M Sorrell (12417871) 14 April 2022 (has links)
<p>Ever since the invention of antibiotics nearly a century ago,the threat of antibiotic resistance has been gradually increasing. As antibiotics are continually prescribed, the rate at which bacteria are becoming resistant to antibiotics is increasing as well. It is projected that antibiotic resistance is one of the largest threats to overall world health, and bacteriophage therapy is one of the leading strategies to combat it. Bacteriophages are viruses that infect and kill specific host bacteria andcan potentially be utilized to kill desired bacteria causing infections that are resistant to antibiotics.</p> <p><br></p> <p>The purpose of this research project is to learn more about the bacteriophage-host interaction through mass spectrometry and bioinformatic tools. This is done through the analysis of proteins and lipids that are produced when the bacteriophage infects the host bacteria. The growth curve of a Passage One From Frozen (P1FF) and a Passage Two From Frozen (P2FF) sample of Mycobacterium smegmatiswas calculated to determine to optimum time for bacteriophage infection. Twobacteriophages were chosen, PotatoSplit and Zalkecks, the Mycobacterium smegmatis samples were infected, samples collected, and mass spectrometry performed. A large portion of this research project is based on the analysis of the proteins and lipids that are produced during each bacteriophage’s infection. Proteomic and lipidomic strategies can be implemented to understand more about the bacteriophage-host interaction and discover any proteins and lipids that are produced at varying timepoints throughout the inoculation process. Bioinformatic tools can then be used to understand the potential functions of each protein or lipid and potential functions or applications of the bacteriophage in general, including the pathogenicity of each bacteriophage.</p> <p><br></p> <p> Determined from proteomic and lipidomic analysis, a list of all proteins and lipids found within each phage infected sample was made. An important trend discovered is that more phage proteins were expressed at later times during the phage infection –Hour 7 and Hour 10, whereas more bacterial proteins were expressed initially –Hour 0 and Hour 3. A case study to investigate the usage of different intensity types produced from mass spectrometry was completed. Overall, it was determined that both the number of phageproteins and bacterial proteins can differ depending on if LFQ or iBAQ intensity type data was used. Correlation between proteins and lipid ontology classes was performed and shows whether groups of lipids are upregulated or downregulated at 14each time point. Understanding the function of lipid ontology groups and the type of regulation provides insight into how the phage or bacteria are potentially using the lipids produced. Some of the main findings include lipids that are involved in bacterial defense mechanisms/energy usage increase over time. Some correlation trends were not consistent across the different bacteriophages, which can be contributed to the different phage life cycles  and therefore different phage-host interactions. Further investigation should be performed to determine the specific biological function of proteins and lipids to confidently make claims about potential applications for each phage. Also, further investigation should be performed to understand if the differences in results between bacteriophage PotatoSplit and Zalkecks are due to the varying life cycles.</p>
34

Étude des interactions physico-chimiques entre les préparations parentérales et un nouveau conditionnement primaire utilisable en unité de préparation centralisée, le flacon Crystal® / Physicochemical interaction study between parenteral products and Crystal® vial, a new primary packaging usable in centralized intravenous additive services

Feutry, Frédéric 08 November 2016 (has links)
La centralisation de la préparation des médicaments injectables à la pharmacie permet d’assurer un haut niveau de qualité mais nécessite une stabilité du médicament dans le conditionnement choisi et une capacité de production suffisantes. Aseptic Technologies a développé un système de remplissage automatisé de conditionnement primaire utilisant un flacon en copolymères d’oléfines cycliques (COC) clos, stérile et prêt à l’emploi appelé « flacon Crystal® ». Ce flacon est rempli à travers le bouchon et est re-scellé par laser, réduisant ainsi le risque de contamination microbiologique.Nous avons évalué les risques liés à l’utilisation du flacon Crystal® :• Le risque de sorption est corrélé à la lipophilie de la substance conditionnée. Pendant 3 mois, nous avons évalué l’évolution de la concentration de 8 molécules cytotoxiques (de coefficients de partage octanol/eau différents) par CLHP/MS. Une méthodologie identique a permis le suivi des concentrations, pendant 24 heures de 3 molécules dérivées du platine par RMN.• Concernant le risque de perméation, nous avons évalué l’évolution des concentrations en phénol et métacrésol dans une solution à 1UI/mL d’insuline conditionnée dans des flacons Crystal® conservés droits et retournés pendant 50 jours par CLHP/UV. Deux formulations différentes de bouchons ont été testées.• Les solutions de pH extrêmes peuvent conduire à la présence de particules dans la solution injectable. L’impact sur la contamination particulaire du conditionnement de ces solutions dans les flacons Crystal® a été étudié et les particules caractérisées.• Les plastifiants peuvent migrer du conditionnement primaire vers la préparation parentérale. Après extraction par reflux à l’isopropanol sur le corps en COC et le bouchon en élastomère, les éventuels plastifiants ont été identifiés et dosés par RMN.Enfin, les stabilités de solutions de céfuroxime, midazolam et noradrénaline conditionnées en flacon Crystal® ont été déterminées et comparées à la seringue en polypropylène (PP).Les concentrations moyennes des 8 molécules cytotoxiques étaient comprises entre 90% et 110% à J62 sans corrélation avec le coefficient de partage. L’absence d’interaction a aussi été démontré pour le carboplatine et l’oxaliplatine par RMN. La précision de la quantification par RMN du cisplatine n’était pas suffisante.Il existe un risque de perméation du métacrésol lors du stockage à 25°C/60%RH pendant 50 jours (perte de 19,7% et de 20,3% pour les flacons Crystal® droits et retournés respectivement). La seconde formulation du bouchon permet de maîtriser le phénomène (perte de 2,6% à J50).Une contamination particulaire importante a été observée lors du conditionnement d’une solution basique et d’un contact avec le bouchon pendant 7 jours (6820 particules 3; 10µm dans un flacon Crystal® de 20mL) Les particules sont fibreuses et composées essentiellement de molécules inorganiques.Les analyses RMN mettent en évidence la présence de plastifiants dans le corps en COC et le bouchon à des concentrations largement en-dessous de la limite de 1000µg/g définie par la réglementation REACH.La solution de céfuroxime (1mL à 10mg/mL) était stable 365 jours à -20°C. Les solutions de midazolam (50mL à 1mg/mL) et de noradrénaline (20mL et 50mL à 0,2mg/mL ; 50mL à 0,5mg/mL) étaient stables 365 jours à 5°C. Des résultats similaires ont été obtenus lors de la conservation en seringue PP.Les flacons Crystal® ne sont pas sujets aux phénomènes de sorption. Il n’y a pas de risque de migration de plastifiants. Le risque de perméation du métacrésol est contrôlé par l’utilisation du nouveau bouchon. Le conditionnement de solutions basiques doit être surveillé. Les solutions de céfuroxime (à -20°C), de midazolam et de noradrénaline (à 5°C) sont stables 1 an. Par rapport à la seringue PP, le flacon Crystal® pourrait être préféré de par son système de remplissage aseptique automatisé ainsi que pour des considérations logistiques, en particulier le gain de place. / Centralized preparation of parenteral products in the pharmacy can ensure a higher quality but requires a stability of the drugs in the chosen primary packaging and a sufficient production capacity. Aseptic Technologies has developed an automated primary packaging filling system using a closed, sterile and ready-to-use cyclic olefin copolymer vial called ‘‘Crystal® vial’’. This vial is filled through the elastomeric septum and then immediately re-sealed by laser, thus reducing the risk of microbial contamination.We have evaluated risks linked to the use of Crystal® vials:- Sorption risk is correlated with substance lipophilicity. During 3 months, we have evaluated concentration evolution of 8 cytotoxic drugs (with different water/octanol partition coefficients) by HPLC/MS. Same methodology was used to measure concentration evolution of 3 platinum-derived drugs by NMR during 24 hours.- About the permeation risk, we have evaluated concentration evolution of phenol and metacresol in a 1UI/mL insulin solution during 50 days by HPLC/UV in Crystal® vials stored upright and upside down. Two stoppers formulations exist and were tested.- Extreme pH solutions can lead to the presence of particles in the parenteral product. Impact of these solutions in Crystal® vials on particles contamination was studied and particles characterized.- Plasticizers may migrate from the primary packaging to the parenteral products. After isopropanol reflux extraction on the COC body and thermoplastic elastomer stopper, potential plasticizers were identified and quantified using NMR.Finally, stabilities of ready-to-use cefuroxime, midazolam and noradrenaline solutions in Crystal® vials were determined and compared to polypropylene syringes.The 8 cytotoxic drugs mean concentrations were between 90% and 110% at day 62 with no correlation with partition coefficient. Lack of interactions was demonstrated too for the oxaliplatin and carboplatin solution by NMR. Accuracy of NMR cisplatin quantification was not sufficient.Studies performed on preservatives highlighted a metacresol permeation risk during storage at 25°C/60%RH for 50 days (loss of 19.7% and 20.3% respectively for Crystal® vials stored upright and upside down). Use of the second formulation stopper allowed a large decrease of permeation (loss of 2.6% at day 50).An important particles contamination was observed only with extrem alkaline pH and contact with the stopper (6820 particles 10µm in a 20mL Crystal® vials stored upside down during 7 days). Particles are fibrous and essentially composed by non-organic substances.NMR analysis highlighted presence of plasticizers in both COC body and elastomer stopper but concentrations were below the 1000µg/g threshold described by the REACH regulation.Cefuroxime solution (1mL at 10mg/mL) was stable 365 days at -20°C. Midazolam solution (50mL at 1mg/mL) and noradrenaline solution (20mL and 50mL at 0.2mg/mL ; 50mL at 0.5mg/mL) were stable 365 days at 5°C. Same results were achieved in polypropylene syringes.Crystal® vials were not subject to sorption phenomena. There was no risk of plasticizer migration. Metacresol permeation risk was controlled using the new stopper. Packaging of alkaline solution must be monitored. Solutions of cefuroxime (-20°C), midazolam and noradrenaline (5°C) are stable 1 year. In regards to storage in polypropylene syringes, Crystal® vials could be prefered for their automated aseptic filling process and for logistic considerations particularly taking into account the space gains.
35

Postoperative Knochendichteänderungen am Femur nach Implantation der zementfreien Zweymüller-Hüftendoprothese unter Berücksichtigung klinischer und röntgenologischer Parameter

Hanebeck, Jan 29 January 2001 (has links)
Bei der Rekonstruktion des durch Krankheit oder Trauma geschädigten Hüftgelenkes hat sich der Ersatz des Gelenkes durch eine totale Endoprothese heute allgemein durchgesetzt. Dabei hat unter Beachtung einer differenzierten Indikationsstellung sowohl die zementierte als auch die zementfreie Technik ihre Anwendungsberechtigung. Das Problem der dauerhaften Verankerung der zementfreien Hüftendoprothese ist jedoch trotz ständiger Weiterentwicklung von Operationstechnik, Implantatdesign und Werkstoffen bis heute nicht abschließend gelöst. Die häufigste Versagensursache ist dabei die aseptische Schaftlockerung, die mit Veränderungen des knöchernen Lagers einhergeht. Mit der Osteodensitometrie existiert eine Technik, die eine schnelle, nichtinvasive und quantitative Beurteilung der Knochenmasse erlaubt. In der vorliegenden Querschnittsstudie wurden 95 Zweymüller-Schaftimplantate zwei, vier bzw. sechs Jahre nach Implantation untersucht. Dabei wurden die Ergebnisse der klinischen Untersuchung und der konventionellen a.p. Röntgenaufnahme den mit Hilfe der DEXA-Technik ermittelten Knochendichteänderungen am Femur gegenübergestellt. Der Vergleich von Knochendichteänderungen in einzelnen Femurabschnitten in Abhängigkeit von der Implantationsdauer läßt Rückschlüsse auf das Schaftdesign zu. / When hip function is several impaired by disease or trauma, total hip replacement is preferred treatment of choice today. The consideration of a differentiated position of indication justifies both - the application of the cemented as well as the cement free technique. But despite of constant further development of operation techniques, design of implantation and the used materials is the problem of a permanent embodiment of the non-cemented hip prosthesis till today not finally solved. The aseptic relaxation of the stem is the most frequent reason for failure. This is accompanied by changes of the osseous bed. With the osteodensitometry exists a technique that makes a fast, non-invasive and quantitative assessment of the bone mass possible. In this present cross-section study 95 Zweymüller-stem-implants were examined two, four and six years after the implantation. The results of the clinical examination and the results of the conventional X-ray picture were compared with the changes of the thigh femur bone density that were ascertained by the DEXA-technique. The comparison of changes of the bone density in single femur sections in dependence on the duration of the implantation allows one to draw conclusions from the design of the stem.
36

Problematika infekcí spojených se zdravotní péčí u vybraných ošetřovatelských činností / Problems of healthcare-associated infection in selected nursing activities

KRAUSE, Martin January 2016 (has links)
The diploma thesis deals with problems of healthcare-associated infection in selected nursing activities. The thesis is a theoretical one; it has been processed by means of review and synthesis. In this thesis, four objectives were set, namely to create a comprehensive overview of the problems of healthcare-associated infection in selected nursing activities. Other objectives were to map and analyze clinically relevant sites of transmission and possibilities of prevention of healthcare-associated infection in selected nursing activities and to propose recommendations for the prevention of these infections. The thesis is divided into several chapters that deal with the characteristics of healthcare-associated infection, focusing on the causative agents, formation, spreading and prevention. It also deals with particular nursing activities. The first chosen activity was the care of medical devices intended for repeated use, with a particular focus on the implementation of their disinfection. Secondly, hand sanitation as a basic factor affecting the transmission of healthcare-associated infection activity was selected. This chapter deals primarily with the hygienic hand disinfection, its indications, methods and implementation of disinfection products. It also deals with strategies for improving hand hygiene and glove use in providing nursing care. As the third nursing activity, aseptic techniques, which are an essential part in providing nursing care, were chosen. The thesis describes three specific clinical nursing procedures: aseptic collection of venous blood from a peripheral vein, preparation and administration of a drug into an existing peripheral venous catheter, and uncomplicated (aseptic) wounds dressing. Processing of the thesis was based on a range of relevant sources from the Czech Republic but also from abroad. It also contains various recommendations of national and international institutions. The thesis can serve as a basis for more effective prevention of healthcare-associated infection in certain areas.
37

Estabilidade do suco tropical de goiaba (Psidium guajava L.) não adoçado obtido pelos processos de enchimento à quente e asséptico. / Stability of the guava tropical juice (Psidium guajava L.) not sweetened gotten by the process hot fill and process aseptic.

Silva, Daniele Sales da January 2007 (has links)
SILVA, Daniele Sales da. Estabilidade do suco tropical de goiaba (Psidium guajava L.) não adoçado obtido pelos processos de enchimento à quente e asséptico. 2007. 98 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2007 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-01T15:20:00Z No. of bitstreams: 1 2007_dis_dssilva.pdf: 571086 bytes, checksum: 1bbf4dff56d5a862c9f6897d9e221dd7 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-01T15:20:12Z (GMT) No. of bitstreams: 1 2007_dis_dssilva.pdf: 571086 bytes, checksum: 1bbf4dff56d5a862c9f6897d9e221dd7 (MD5) / Made available in DSpace on 2016-06-01T15:20:12Z (GMT). No. of bitstreams: 1 2007_dis_dssilva.pdf: 571086 bytes, checksum: 1bbf4dff56d5a862c9f6897d9e221dd7 (MD5) Previous issue date: 2007 / O Brasil é um dos três maiores produtores mundiais de frutas, sendo que a evolução do consumo das frutas processadas não só no Brasil, mas a nível mundial aponta caminho da agregação de valor, na qual o mercado de frutas industrializadas apresenta maior destaque que o de frutas in natura. A praticidade aliada à preocupação com a saúde tem sido um dos fatores para o aumento do consumo de sucos industrializados. A goiaba é um dos frutos de maior importância nas regiões tropicais e subtropicais não só pelo seu elevado valor nutritivo, mas também pela excelente aceitação do consumo in natura, pela capacidade de desenvolvimento em condições adversas e pela grande aplicação industrial. A região Nordeste é a maior responsável pela produção de goiaba no Brasil contribuindo com cerca de 45,40% da produção nacional. Este trabalho teve como objetivo avaliar e comparar a estabilidade do suco tropical de goiaba obtido pelos processos de enchimento à quente e asséptico com relação aos aspectos das alterações químicas, físico-químicas, microbiológicas e sensoriais, durante um período de 250 dias de armazenamento em condições similares às de comercialização (28 ± 2ºC). Os sucos estudados não apresentaram interação significativa entre as embalagens estudadas e o tempo de armazenamento. Os parâmetros vitamina C, SO2 e fenólicos totais foram os mais afetados ao longo do armazenamento. Para os resultados da análise sensorial, estes praticamente não se alteraram até o tempo 150 dias de armazenamento. Com relação a avaliação microbiológica, os sucos encontram-se comercialmente estéreis.
38

Distribuce a počty otěrových částic v okolí kloubních náhrad / Distribution and number of wear debris particles around jouint replacements

Veselý, Filip January 2013 (has links)
Aseptic loosening due to polyethylene wear presents one of the most frequently occurring joint replacement complications requiring a revision surgery. Numerous scientific works and publications deal with the issue of morphology, determination and distribution of wear particles. Few studies, however, determine reliably amounts of particles in individual periprosthetic zones. The objective of this work was to evaluate the correlation between amounts of wear particles and periprosthetic osteolysis findings. Description of distribution of these particles in the surroundings of joint replacement presented further objectives of the work. Wear particles were isolated from granuloma obtained during revisions of total hip replacements. Amounts of wear particles were determined using IRc. These findings were correlated with X-ray examinations and intraoperative findings. Method of progressive enzymatic degradation of tissue was used in order to describe wear particles distribution in polyethylene granuloma and surrounding periprosthetic tissues. Results showed uneven incidence of wear particles in the surroundings of the total joint replacement. The incidence correlated with X-ray examinations and intraoperative findings. Distribution of particles was described as well as new determination methods and further...
39

Avaliação de um sistema asséptico para leite longa vida em embalagem flexível institucional do tipo bag-in-box / Evaluation of an aseptic system for long life milk in institutional package bag-in -box type

Cardoso, Claudio Fernandes 04 July 2011 (has links)
Orientador: José de Assis Fonseca Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T02:06:39Z (GMT). No. of bitstreams: 1 Cardoso_ClaudioFernandes_D.pdf: 26277698 bytes, checksum: d17c520e85b9389e672d2641e795333d (MD5) Previous issue date: 2011 / Resumo: Esta pesquisa teve como objetivo avaliar o desempenho de um sistema asséptico piloto para a produção de leite UHT (Ultra Hight-Temperature), com capacidade de 1.000 L/h, em embalagens flexíveis institucionais do tipo Bag-in-box (BIB). As embalagens estudadas eram compostas de um filme de polietileno de baixa densidade (PEBD) e um filme de polietileno tereftalato metalizado (PETmet), com volume de 2.000 mL, desenvolvido especialmente para o envase asséptico de produtos lácteos. Leite cru refrigerado tipo A foi utilizado como matéria-prima. O envase do leite UHT foi realizado através de uma dosadeira semi-automática dentro de uma Sala Limpa ISO posicionada sobre o bocal de enchimento das embalagens. O sistema foi avaliado através da identificação e monitoramento de pontos de controle do processo, testes de esterilidade comercial, análises sensorial e físico-química do produto, bem como avaliações da embalagem. O desempenho das embalagens BIB foi avaliado através de ensaios de caracterização, integridade do sistema e estudos de estabilidade microbiana e testes de efetividade de esterilização. As embalagens foram esterilizadas com o uso de radiação ionizante (gama), com dose de 15 kGy. Os ensaios foram conduzidos através da produção de 4 lotes experimentais de leite UHT, obtido em trocador de calor a placas (140 °C por 5 s). A taxa de defeito encontrada nos testes de esterilidade comercial variou entre 0 e 6,7%, sendo que a principal causa de defeitos foi associada aos problemas inerentes a operacionalidade da linha, como falhas nas vedações das junções de tubulações e bombas centrífugas. Os resultados da avaliação dos pontos de controle do processo e embalagem indicaram um bom desempenho do sistema, justificado pela ausência de microorganismos viáveis. O leite UHT acondicionado nas embalagens BIB teve sua vida de prateleira estimada em até 27 semanas de estocagem, valor este muito superior quando comparado às amostras controle de leite UHT comercial, acondicionado em embalagens laminadas cartonadas, que teve sua vida de prateleira estimada em 19 semanas. A diferença de estabilidade físico-química, microbiológica e sensorial entre as amostras processadas e a comercial foi associada às propriedades de barreira das estruturas das embalagens à luz e ao oxigênio, bem como pela qualidade da matéria-prima utilizada. O sistema asséptico piloto avaliado correspondeu às expectativas de desempenho e atendeu aos requisitos estabelecidos pelo Codex Alimentarius. Concluiu-se que o sistema apresenta potencial para utilização por indústrias de laticínios visando atender o mercado institucional de leite longa vida / Abstract: The aim of this research was to evaluate the performance of an aseptic pilot system for the production of Ultra High Temperature (UHT) milk, with 1.000 L/h capacity, filled in flexible institutional packages Bag-in-box (BIB) type. The BIB packages were constructed with one layer of low density polyethylene film (LDPE) and another one of metalized polyethylene terephthalate film (PETmet), with 2.000 mL capacity, specially developed for the aseptic filling of dairy products. Type-A milk was used as raw material and the UHT milk filling was made by a semiautomatic machine located inside a ISO Clean room. The system was evaluated by the identification and monitoring of the control points during the process and also by commercial sterility tests, sensorial and physical-chemistry analysis and packages evaluations. The BIB packages were sterilized by gamma radiation with minimum doses of 15 kGy. The assays were conducted by the production of 4 experimental batches processed in a plate heat exchanger (140 °C/5 s). The defect rates founded were between 0 and 6.7% and these values can be explained by problems linked to the pilot plant operation, like failures in the connections of pipes and centrifugal pumps. The results of the control points evaluation and also BIB packages showed a good performance of the entire process, justified by the absence of viable microorganisms. The milk filled in BIB packages targeted until 27 weeks of shelf life, a superior value when it was compared to the commercial UHT samples, which targeted just 19 weeks. The difference of physical-chemistry, microbiology and sensory stability between the processed samples and the commercial one was associated to the oxygen and light barriers properties and also to the raw milk quality used during the processes. The pilot aseptic system evaluated attended to the Codex Alimentarius requirements and it could be concluded that the system showed potential for application in dairy industry in view of the long life milk institutional market / Doutorado / Tecnologia de Alimentos / Doutor em Tecnologia de Alimentos
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Stability of the guava tropical juice (Psidium guajava L.) not sweetened gotten by the process hot fill and process aseptic. / Estabilidade do suco tropical de goiaba (Psidium guajava L.) nÃo adoÃado obtido pelos processos de enchimento à quente e assÃptico.

Daniele Sales da Silva 27 April 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O Brasil à um dos trÃs maiores produtores mundiais de frutas, sendo que a evoluÃÃo do consumo das frutas processadas nÃo sà no Brasil, mas a nÃvel mundial aponta caminho da agregaÃÃo de valor, na qual o mercado de frutas industrializadas apresenta maior destaque que o de frutas in natura. A praticidade aliada à preocupaÃÃo com a saÃde tem sido um dos fatores para o aumento do consumo de sucos industrializados. A goiaba à um dos frutos de maior importÃncia nas regiÃes tropicais e subtropicais nÃo sà pelo seu elevado valor nutritivo, mas tambÃm pela excelente aceitaÃÃo do consumo in natura, pela capacidade de desenvolvimento em condiÃÃes adversas e pela grande aplicaÃÃo industrial. A regiÃo Nordeste à a maior responsÃvel pela produÃÃo de goiaba no Brasil contribuindo com cerca de 45,40% da produÃÃo nacional. Este trabalho teve como objetivo avaliar e comparar a estabilidade do suco tropical de goiaba obtido pelos processos de enchimento à quente e assÃptico com relaÃÃo aos aspectos das alteraÃÃes quÃmicas, fÃsico-quÃmicas, microbiolÃgicas e sensoriais, durante um perÃodo de 250 dias de armazenamento em condiÃÃes similares Ãs de comercializaÃÃo (28  2ÂC). Os sucos estudados nÃo apresentaram interaÃÃo significativa entre as embalagens estudadas e o tempo de armazenamento. Os parÃmetros vitamina C, SO2 e fenÃlicos totais foram os mais afetados ao longo do armazenamento. Para os resultados da anÃlise sensorial, estes praticamente nÃo se alteraram atà o tempo 150 dias de armazenamento. Com relaÃÃo a avaliaÃÃo microbiolÃgica, os sucos encontram-se comercialmente estÃreis.

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