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91	可贖回雪球式商品的評價與避險曹若玹 Unknown Date (has links) 本文採用Lognormal Forward LIBOR Model (LFM) 利率模型，針對可贖回雪球式債券進行相關的評價與避險分析，而由於此商品的計息方式為路徑相依型態，價格沒有封閉解，故必須利用數值方法來進行評價。過去通常使用二元樹或三元樹的方法來評價具有可贖回特性的商品，但因為LFM是屬於多因子模型，所以不容易處理建樹的過程。而一般路徑相依商品的評價是使用蒙地卡羅法來進行，但是標準的蒙地卡羅法不易處理美式或百慕達式選擇權的問題，因此，本研究將使用由Longstaff and Schwartz(2001)所提出的最小平方蒙地卡羅法，來處理同時具有可贖回與路徑相依特性的商品評價並進行實證研究。 / 此外，關於可贖回商品的避險參數部分，由於商品的價格函數不具有連續性，若在蒙地卡羅法之下直接使用重新模擬的方式來求算避險參數，將會造成不準確的結果，而Piterbarg (2004)提出了兩種可用來計算在LFM下可贖回商品避險參數的方法，其實証結果發現所求出的避險參數結果較準確，因此本研究將此方法運用至可贖回雪球式利率連動債券，並分析各種參數變化對商品價格的影響大小，便於進行避險工作。利率連動債券最小平方蒙地卡羅參數校準提前贖回避險參數 BGM LFM LIBOR Greeks calibration snowball Sausage Monte Carlo pathwise
92	Filmes à base de blenda gelatina-quitosana com agentes ativos nanoemulsificados: desenvolvimento, caracterização e aplicação na conservação de mortadela fatiada refrigerada / Gelatin-chitosan blend based films loaded with nanoemulsified active agents: development, characterization and application to conservation of refrigerated sliced mortadella sausage Luis Jaime Pérez Córdoba 26 July 2018 (has links) Um problema importante na produção de filmes ativos utilizando agentes ativos lipofílicos é a dificuldade de dispersão desses agentes na solução formadora de filme (SFF). As nanoemulsões podem ser uma alternativa para dispersar esses compostos na matriz biopolimérica. Os objetivos gerais desta pesquisa foram: 1) Desenvolver nanoemulsões óleo-em-água (O/A), com três agentes ativos na fase óleo, sendo dois antimicrobianos - cinamaldeído e óleo essencial de alho - e um antioxidante - alfa-tocoferol, e caracterizar essas nanoemulsões, inclusive sua estabilidade; e 2) Desenvolver, caracterizar e aplicar filmes ativos à base de gelatina-quitosana (G-Q), ativados com nanoemulsões O/A preparadas nas condições ótimas de processo: N1: α-tocoferol/cinamaldeído; N2: α-tocoferol/óleo essencial de alho; N3: α-tocoferol/cinamaldeído e óleo essencial de alho; e N4: óleo de canola. As nanoemulsões O/A foram preparadas usando um microfluidizador e Tween 20 e Span 60 como emulsificantes, caracterizadas e incorporadas na SFF. Os filmes foram produzidos pela técnica de Casting incorporando 0 ou 5 g agente ativo nanoemulsificado/100 g biopolímero e usando glicerol como plastificante. Os filmes foram caracterizados em termos de propriedades físicas, mecânicas, de permeabilidade ao vapor de água e isotermas de sorção, ópticas, microestruturais, e atividades antimicrobiana e antioxidante. Além disso, um estudo de migração dos agentes ativos em simuladores de alimentos foi realizado. A mortadela fatiada foi embalada em bandejas de poliestireno usando filmes como separador de fatias. Posteriormente, foi avaliada a aceitação sensorial da mortadela e sua vida útil com base em análises físico-químicas e microbiológicas. Os resultados mostraram emulsões O/A com tamanho de gota nanométrico, distribuição monomodal, potencial ζ >-30 mV, alta estabilidade física e eficiência de encapsulação e propriedades ativas. Por outro lado, os filmes ativos não apresentaram diferenças significativas (p>0,05) quanto à espessura, umidade, permeabilidade ao vapor de água e propriedades térmicas. A solubilidade em água, ângulo de contato, transmissão de luz, rigidez e resistência à tração e o brilho dos filmes foram reduzidos (p<0,05), enquanto a deformação na ruptura, opacidade, grau de inchamento, cor e rugosidade da superfície aumentaram consideravelmente (p<0,05) em razão da incorporação das nanoemulsões. Os modelos matemáticos de BET, GAB, Peleg e Oswin descreveram o comportamento de absorção de vapor de água dos filmes. As análises de DSC, FTIR e de difração de raios-X sugeriram compatibilidade entre a gelatina e a quitosana. Uma boa distribuição das nanogotas de óleo que encapsulavam os agentes ativos na matriz biopolimérica foi confirmada pelas análises de MEV e MFA. As nanoemulsões e os filmes ativos foram efetivos contra a Pseudomonas aeruginosa e Listeria monocytogenes e apresentaram atividade antioxidante frente aos radicais DPPH•, ABTS•+ e o reagente FRAP. As cinéticas de migração dos agentes ativos apresentaram comportamento Fickiano, com valores de coeficientes de difusão efetiva (D) entre 10-14 e 10-15 m2/s. Por outro lado, as fatias de mortadela embaladas sem filme foram as mais aceitas sensorialmente. Porém, o filme ativo utilizado ofereceu a maior ação antimicrobiana contra a L. monocytogenes e P. aeruginosa, inicialmente inoculadas na mortadela, além do maior efeito protetor contra bactérias deteriorantes, assim como inibiu a oxidação lipídica por mais tempo (5 dias) durante o estudo de vida útil. Em geral, este estudo evidenciou que os filmes à base de G-Q carregados com agentes ativos nanoemulsificados pode ter potencial como material de embalagem para melhorar a vida útil de alimentos. / A major problem in the production of active films using lipophilic active agents is their poor dispersion in the film-forming solution (FFS). Nanoemulsions may be an alternative to disperse these compounds within the biopolymeric matrix. The main aims of this research were: 1) to develop oil-in-water (O/W) nanoemulsions incorporated with three active agents in the oil phase, two antimicrobials - cinnamaldehyde and garlic essential oil - and one antioxidant - α-tocopherol and characterize those nanoemulsions, even their stability, and 2) Develop, characterize and applicate gelatin-chitosan (G-Ch) based films activated with O/W nanoemulsions prepared under optimal conditions: N1: α-tocopherol/cinnamaldehyde; N2: α-tocopherol/garlic essential oil; N3: α-tocopherol/cinnamaldehyde and garlic essential oil; and N4: canola oil. The O/W nanoemulsions were prepared using a microfluidizer and Tween 20 and Span 60 as emulsifiers, characterized, and then loaded into the FFS. The films were produced by the casting method incorporating 0 or 5 g of nanoemulsified active agent/100 g biopolymer, using glycerol as a plasticizer, and subsequently characterized in terms of their physical, mechanical, water vapor permeability, water sorption, optical, microstructural, antimicrobial and antioxidant properties. In addition, a study of active agent migration into food simulants was performed. The sliced mortadella was packed in polystyrene trays using films as a slice separator. After, a sensorial acceptance evaluation and shelf life study, based on physicochemical and microbiological analyses, were performed for the mortadella sausage. The results showed O/A emulsions with nanometric droplet size, monomodal distribution, ζ potential greater than -30 mV, high physical stability, high encapsulation efficiency, and active properties. On the other hand, the active films presented no significant differences (p>0.05) in terms of thickness, moisture content, water vapor permeability, and thermal properties. The solubility in water, contact angle, light transmission, tensile strength, and brightness of films were reduced (p<0.05), whilst the deformation at break, opacity, degree of swelling, color, and surface roughness considerably increased (p<0.05), due to the incorporation of nanoemulsions. The mathematical models of BET, GAB, Peleg and Oswin described the water vapor absorption behavior of the films. The DSC, FTIR, and x-ray analyses suggested compatibility between the gelatin and chitosan. A good distribution of the oil nanodroplets encapsulating the active agents within the matrix was confirmed by AFM and SEM analyses. The active nanoemulsions and films were effective against Pseudomonas aeruginosa and Listeria monocytogenes, and showed antioxidant activity against the DPPH• and ABTS•+ free radicals, as well as the FRAP reagent. The kinetic migration of the active agents presented a Fickian behavior with values of effective diffusion coefficients (D) between 10-14 and 10-15 m2/s. On the other hand, the mortadella slices packed without films were the most sensorially accepted. However, the active films used offered the greatest effectiveness against L. monocytogenes and P. aeruginosa initially inoculated in the mortadella sausage, and highest protective effect against spoilage bacteria, as well as inhibiting lipid oxidation for longer time (5 days) during the shelf life study. Overall, this study offered clear evidence that G-Ch based films, loaded with nanoemulsified active agents, can have potential as packaging material for enhancing the shelf life of food. α-tocoferol Biopolímero Cinamaldeído Filmes ativos Mortadela Nanoemulsão Óleo essencial de alho Vida útil α-tocopherol Active films Biopolymer Cinnamaldehyde Garlic essential oil Mortadella sausage Nanoemulsion Shelf life
93	STAPHYLOCOCCUS XYLOSUS E LACTOCOCCUS LACTIS SSP LACTIS NATIVOS UTILIZADOS NA ELABORAÇÃO DE SALAME TIPO ITALIANO / NATIVE STAPHYLOCOCCUS XYLOSUS AND LACTOCOCCUS LACTIS SSP LACTIS USED IN THE ELABORATION FERMENTED ITALIAN SAUSAGE Cirolini, Andréia 25 February 2008 (has links) Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study was to produce and to test the performance of native starters cultures in the elaboration of fermented Italian sausage in relation to the security and quality of the sausages. In the first experiment strains of Staphylococcus xylosus isolated from colonial sausages, were characterized and after identified for the Kit Api Staph (Biomérieux). In the second experiment, the microorganism Lactococcus lactis ssp lactis was fermented in pork plasma culture medium and evaluated its efficiency in relation to MRS broth, through microbiological analyses and optic density (OD). In the third experiment the isolated and multiplied cultures were added in dry fermented sausages, elaborating four treatments: T1 - addition of commercial starters (Staphylococcus xylosus and Lactococcus lactis ssp lactis); T2 - mixture of isolated Staphylococcus xylosus more commercial Lactococcus lactis ssp lactis ; T3 - mixture of isolated Lactococcus lactis ssp lactis more commercial Staphylococcus xylosus and T4 - Staphylococcus xylosus and Lactococcus lactis ssp lactis both isolated, evaluating its influence on the microbiological, physico-chemical and sensorial characteristics. About 13.3% of the colonies isolated of sausages were identified as Staphylococcus xylosus. The maximum growth of Lactococcus lactis ssp lactis, in pork plasma culture medium was 8.58 Log UFC.mL-1 in 27 hours, and the OD 0.88. In the MRS broth the growth reached the maximum peak (8.70 Log UFC.mL-1) in 6 hours, presenting OD of 0.81. All the elaborated sausages presented a significant decreased of pH and a reduction in the water activity, ensuring a microbiological security to the products. In relation the lipid oxidation, the treatment that contained isolated strains of Staphylococcus xylosus presented significantly lower values than the other treatments. The sausages elaborated with both strains isolated presented better sensorial results than the sausages elaborated with commercial starters cultures. Therefore, this study indicated that would be promising to extend the availability of microorganisms for industrial use from the selection of native cultures, that the pork plasma culture medium becomes an alternative for the multiplication of lactic acid bacteria, because it presented a similar fermentation performance to the commercial culture medium and that the addition of natives starters cultures can be used in the elaboration of fermented Italian sausages, providing safety products and with differentiated flavor. / Este trabalho teve por objetivo produzir e testar o desempenho de culturas starters nativas na fabricação de salame tipo Italiano quanto à segurança e qualidade dos salames. No primeiro experimento, cepas de Staphylococcus xylosus foram isoladas de salames coloniais, caracterizadas e após identificadas pelo Kit Api Staph (Biomérieux). No segundo experimento, o microrganismo Lactococcus lactis ssp lactis foi fermentado em meio de cultura de plasma suíno e avaliado sua eficiência em relação ao caldo MRS, através de análises microbiológicas e densidade óptica (DO). No terceiro experimento, as culturas isoladas e multiplicadas foram adicionadas em salame, elaborando-se quatro tratamentos: T1 - adição de starters comerciais (Staphylococcus xylosus e Lactococcus lactis ssp lactis); T2 - mistura de Staphylococcus xylosus isolado mais Lactococcus lactis ssp lactis comercial; T3 - mistura de Lactococcus lactis ssp lactis isolado mais Staphylococcus xylosus comercial e T4 - Staphylococcus xylosus e Lactococcus lactis ssp lactis ambos isolados, avaliando sua influência nas características microbiológicas, físico-químicas e sensoriais. Foram identificadas 13,3% das colônias isoladas de salames coloniais como Staphylococcus xylosus. O crescimento máximo de Lactococcus lactis ssp lactis, em meio de cultura de plasma suíno, foi de 8,58 Log UFC.mL-1 no tempo de 27 horas e DO de 0,88. Em caldo MRS, o crescimento atingiu pico máximo (8,70 Log UFC.mL-1) em 6 horas, apresentando uma DO de 0,81. Todos os salames elaborados apresentaram uma queda de pH significativa e também uma redução na atividade de água, garantindo uma segurança microbiológica aos produtos. Em relação a oxidação lipídica, os tratamentos que continham cepas de Staphylococcus xylosus isolados apresentaram valores significativamente menores que os outros tratamentos. Os salames elaborados com as duas cepas isoladas (T4) apresentaram melhores resultados sensoriais quando comparados com salames elaborados com culturas starters comerciais. Portanto, este estudo indicou que seria promissor ampliar a disponibilidade de linhagens para uso industrial proveniente da seleção de culturas nativas, que o meio de cultura de plasma suíno torna-se uma alternativa para a multiplicação de bactérias ácido lácticas, pois apresentou um desempenho semelhante à fermentação do meio de cultura comercial e que a adição de culturas starters nativas pode ser utilizada na elaboração de salames, proporcionando produtos seguros e com flavor diferenciado. Staphylococcus xylosus Lactococcus lactis ssp lactis Plasma suíno Salame tipo Italiano Culturas starters Staphylococcus xylosus Lactococcus lactis ssp lactis Pork plasma Fermented Italian sausage Starters cultures
94	Archaeologic inspection of the Milky Way using vibrations of a fossil : Seismic, spectroscopic and kinematic characterization of a binary metal-poor Halo star Byström, Amanda January 2020 (has links) The Milky Way has undergone several mergers with other galaxies during its lifetime. The mergers have been identified via stellar debris in the Halo of the Milky Way. The practice of mapping these mergers is called galactic archaeology. To perform this archaeologic inspection, three stellar features must be mapped: chemistry, kinematics and age. Historically, the latter has been difficult to determine, but can today to high degree be determined through asteroseismology. Red giants are well fit for these analyses. In this thesis, the red giant HE1405-0822 is completely characterized, using spectroscopy, asteroseismology and orbit integration, to map its origin. HE1405-0822 is a CEMP-r/s enhanced star in a binary system. Spectroscopy and asteroseismology are used in concert, iteratively to get precise stellar parameters, abundances and age. Its kinematics are analyzed, e.g. in action and velocity space, to see if it belongs to any known kinematical substructures in the Halo. It is shown that the mass accretion that HE1405-0822 has undergone has given it a seemingly younger age than probable. The binary probably transfered C- and s-process rich matter, but how it gained its r-process enhancement is still unknown. It also does not seem like the star comes from a known merger event based on its kinematics, and could possibly be a heated thick disk star. / Vintergatan har genomgått flera sammanslagningar med andra galaxer under sin livstid. Dessa sammanslagningar har identifierats genom rester av stjärnor i Vintergatans Halo. Arbetssättet för att kartlägga dessa sammanslagningar kallas galaktisk arkeologi. För att kunna göra en arkeologisk undersökning krävs tre egenskaper hos de undersökta stjärnorna: kemi, kinematik och ålder. Historiskt sett har den sistnämnda varit svår att bestämma, men kan idag bestämmas med hög precision m.h.a. asteroseismologi. Röda jättar lämpar sig väl för dessa analyser. I denna uppsats undersöks den röda jätten HE1405-0822. Den kartläggs helt m.h.a. spektroskopi, asteroseismologi och bananalys. HE1405-0822 är en CEMP-r/s-förhöjd stjärna i ett binärt system. Spektroskopi och asteroseismologi används tillsammans, iterativt, för att få precisa stjärnparametrar, kemiskt innehåll och ålder. Dess kinematik analyseras, t.ex. i verkan- och hastighetsrummet, för att se om den tillhör någon känd kinematisk substruktur i Halon. Det visas att massöverföringen som HE1405-0822 genomgått har gett den en skenbart yngre ålder än vad som är troligt. Denna binära kompanjon har troligtvis övertfört C- och s-process-rikt material, men hur den fick sin mängd r-processämnen är fortfarande okänt. Det verkar inte som att stjärnan kommer från någon tidigare kartlagd sammanslagning baserat på dess kinematik, och skulle kunna vara en stjärna med upphettad kinematik från Vintergatans tjocka disk. Milky Way Halo galactic archaeology asteroseismology binary star CEMP stars CEMP-r/s stars stellar age stellar mass chemical abundance pattern Gaia-Enceladus Gaia-Sausage Sequoia spectroscopy metal-poor Astronomy, Astrophysics and Cosmology Astronomi, astrofysik och kosmologi
95	Untersuchungen zur Tenazität des Norovirus-Surrogates Felines Calicivirus unter dem Einfluss von D/L-Milchsäure, Natriumchlorid und Natriumnitrit sowie zum Verhalten in Rohwürsten: Untersuchungen zur Tenazität des Norovirus-Surrogates Felines Calicivirus unter dem Einfluss von D/L-Milchsäure, Natriumchlorid und Natriumnitrit sowie zum Verhalten in Rohwürsten Heinze, Janin 16 March 2010 (has links) Noroviren gelten neben Rotaviren, Salmonellen und Campylobacter spp. derzeit als Hauptursache infektiöser meldepflichtiger Gastroenteritiden des Menschen in Deutschland. Im Jahr 2008 wurden 212.692 Fälle norovirusbedingter Erkrankungen gemeldet (RKI 2009b). Dabei spielen lebensmittelassozierte Infektionen eine bedeutende Rolle. Besonders rohe und unerhitzt verzehrte Produkte bergen ein Risikopotential. Neben Muscheln, Salaten und Früchten konnten die Erreger auch aus Rohwurstprodukten isoliert werden. Aus mikrobiologischer Sicht sind Rohwürste bereits als Risikoprodukte bekannt. Bisher existieren jedoch nur unzureichende wissenschaftliche Ergebnisse über die Infektionsgefahr durch Viren in Lebensmitteln. In der vorliegenden Arbeit wurde die Tenazität und Inaktivierungskinetik von Noroviren anhand des Norovirus-Surrogates Felines Calicivirus untersucht. Zunächst wurde in Suspensionsversuchen der Einfluss verschiedener Konzentrationen von D/L-Milchsäure (0,1; 0,15; 0,2; 0,3 und 0,4 %), Natriumchlorid (2; 6; 12 und 20 %) und Natriumnitrit (100; 150 und 200 ppm) über einen Zeitraum von 7 Tagen bei 4 und 20 °C auf das Virus geprüft. Anschließend wurden Versuchsreihen mit artifiziell kontaminierten Rohwürsten durchgeführt. Der Infektiositätsnachweis erfolgte im Crandell-Reese-Feline-Kidney-Zellkultursystem. In den Suspensionsversuchen zeigte sich eine konzentrations-, zeit- und temperaturabhängige Wirkung der geprüften Parameter. Signifikante Infektiositätsreduktionen ergaben sich bei 20 °C- Lagerung für D/L-Milchsäure-Konzentrationen ab 0,15 % und bei 4 °C -Lagerung ab 0,3 %. Natriumchlorid bewirkte signifikante Titerreduktionen bei 20 °C-Lagerung ab einer NaCl-Konzentration von 2 %, jedoch nicht unter Kühlbedingungen. Die Reduktion der Virusinfektiosität nahm mit steigender Natriumchlorid- bzw. D/L-Milchsäurekonzentration zu. Für praxisübliche Konzentrationen von Natriumnitrit konnte keine zusätzliche Reduktion der Infektiosität nachgewiesen werden. In den Versuchsreihen mit kurz- und langgereiften Rohwürsten erwies sich FCV als sehr stabil. In beiden Produkten konnte bis zum Ende des Versuchszeitraumes nach 21 bzw. 56 Tagen infektiöses Virus nachgewiesen werden. Somit könnten Rohwurstprodukte bei einer möglichen Kontamination mit Noroviren zum Zeitpunkt des Verzehrs ein Gesundheitsrisiko für den Verbraucher darstellen. Jedoch zeigten sich auch deutliche temperatur- und zeitabhängige Wirkungen. Ein positiver Einfluss auf die Inaktivierung ist durch die Anwendung von Reife- und Lagerungstemperaturen um 22 °C zu erwarten. Es kam zu einer kontinuierlichen Virustiterreduktion von insgesamt 1,6 log10 TCID50 / g (für kurzgereifte Produkte) bzw. 3,1 log10 TCID50 / g (für langgereifte Produkte). Eine Beeinflussung der Tenazität des Norovirus-Surrogates FCV durch spezifische Herstellungs- und Lagerungsbedingungen ist somit möglich. Insbesondere die gezielte Kombination einzelner Faktoren miteinander, wie NaCl- und Milchsäuregehalt der Rohwurst, in Verbindung mit spezifischer Lagerungstemperatur und –dauer führt zu effektiver Infektiositätsminderung potentiell enthaltener Viren. Die so erzielte Risikominimierung durch Kombination ausgewählter Parameter bedeutet für die Rohwurstproduktion eine sowohl effiziente, als auch praktikable Möglichkeit, die Lebensmittelsicherheit in Bezug auf virale Infektionserreger deutlich zu erhöhen. info:eu-repo/classification/ddc/610 ddc:610
96	Optimizaci��n del proceso de secado en base a criterios de calidad. Aplicaci��n al dise��o de un alimento c��rnico enriquecido en fibra alimentaria Eim Iznardo, Valeria Soledad 10 September 2012 (has links) En el dise��o de embutidos crudos curados enriquecidos en fibra alimentaria, es esencial la obtenci��n de ingredientes funcionales de elevada calidad, que puedan ser incorporados en la formulaci��n del embutido generando las menores modificaciones de las caracter��sticas f��sico-qu��micas y sensoriales del alimento. El principal objetivo de este trabajo consisti�� en optimizar la formulaci��n de un embutido crudo curado enriquecido en un concentrado de fibra alimentaria de zanahoria. La formulaci��n ��ptima debe proporcionar el contenido m��ximo de fibra alimentaria y producir los m��nimos cambios de calidad respecto al producto tradicional. Se ha propuesto una metodolog��a para optimizar ambos, la obtenci��n de un concentrado de fibra alimentaria de alta calidad y tambi��n la formulaci��n de un embutido crudo curado (sobrasada) enriquecido en fibra alimentaria. En primer lugar, se ha desarrollado un procedimiento que consiste en la modelizaci��n, simulaci��n y optimizaci��n del proceso de secado convectivo de zanahoria. El procedimiento de optimizaci��n no solo se refiere a la transferencia de materia, sino tambi��n se incluyen los criterios relacionados con los atributos de calidad del producto final. Una vez obtenido el ingrediente funcional de calidad, fue incorporado en la formulaci��n de la sobrasada. La cantidad ��ptima de concentrado de fibra alimentaria de zanahoria necesaria para obtener un embutido enriquecido de calidad se estim�� mediante el an��lisis de los efectos de la adici��n de fibra alimentaria de zanahoria en el proceso de maduraci��n-secado de sobrasada. / To design dry fermented sausages enriched in dietary fibre, it is essential to obtain high quality functional ingredients, which can be incorporated into sausage formulation with minor modifications of the physico-chemical and sensory properties of food. The main objective of this study was to optimize the formulation of a dry fermented sausage enriched with a dietary fibre concentrate from carrot. The optimal formulation should provide maximum dietary fibre content and produce minimal quality changes from the traditional product. A methodology has been proposed to optimize both the acquisition of a high quality fibre concentrate and also for the formulation of a dry fermented sausage (sobrassada) enriched in dietary fibre. First, a procedure comprised of mathematical modelling, simulation and optimization of the convective carrot drying process was developed. The optimization procedure was not only concerned with mass transfer but also included criteria related to quality attributes of the final product. Once the high quality functional ingredient was obtained, it was incorporated into the sobrassada formulation. The optimal amount of carrot dietary fibre concentrate necessary to obtain a high quality enriched sausage was estimated by analysing the effects of carrot dietary fibre addition to the ripening-drying process of sobrassada. / En el disseny d'embotits crus curats enriquits en fibra aliment��ria, ��s essencial l'obtenci�� d'ingredients funcionals d'elevada qualitat que puguin ser incorporats en la formulaci�� de l'embotit generant les menors modificacions de les caracter��stiques fisicoqu��miques i sensorials de l'aliment. El principal objectiu d'aquest treball va consistir a optimitzar la formulaci�� d'un embotit cru curat enriquit en un concentrat de fibra aliment��ria de pastanaga. La formulaci�� ptima ha de proporcionar el contingut m��xim de fibra aliment��ria i produir la menor quantitat possible de canvis qualitatius respecte al producte tradicional. S'ha proposat una metodologia per optimitzar ambd��s aspectes esmentats, l'obtenci�� d'un concentrat de fibra aliment��ria d'alta qualitat i tamb�� la formulaci�� d'un embotit cru curat (sobrassada) enriquit en fibra aliment��ria. En primer lloc, s'ha desenvolupat un procediment que consisteix en la modelitzaci��, simulaci�� i optimitzaci�� del proc��s d'assecatge convectiu de pastanaga. El procediment d'optimitzaci�� no nom��s fa refer��ncia a la transfer��ncia de mat��ria, sin�� que tamb�� inclou els criteris relacionats amb els atributs de qualitat del producte final. Una vegada obtingut l'ingredient funcional de qualitat, va ser incorporat en la formulaci�� de la sobrassada. La quantitat ��ptima de concentrat de fibra aliment��ria de pastanaga necess��ria per obtenir un embotit enriquit de qualitat es va estimar mitjan��ant l'an��lisi dels efectes de l'addici�� de fibra aliment��ria de pastanaga en el proc��s de maduraci��/assecat de sobrassada. Enginyeria Qu��mica 54 - Qu��mica
97	Réduction combinée en chlorure de sodium et en matière grasse animale lors de la fabrication du saucisson sec : effets sur les propriétés physicochimiques et les réactions biochimiques en lien avec la production aromatique et les attributs sensoriels / Combined salt and animal fat reductions during dry-fermented sausage manufacture : effects on physical-chemical properties and biochemical reactions related to the aromatic compound production and sensory attributes Safa, Hassan 25 January 2016 (has links) Du fait de problèmes de santé publique, l’industrie agroalimentaire doit réduire la quantité de sel et de matière grasse dans les aliments, et donc dans les charcuteries. Lors de la fabrication des saucissons secs, une diminution combinée des taux de sel et de matière grasse animale peut se traduire par des problèmes de stabilité microbiologique, des défauts d’arôme et de texture dus à des modifications physicochimiques et biochimiques. Dans ce contexte, les objectifs de cette thèse étaient : (1) d’étudier l’impact d’une réduction directe des teneurs en sel et en matière grasse animale sur les évolutions physicochimiques et biochimiques au sein des produits, (2) d’identifier les composés aromatiques responsables de l’arôme du saucisson sec, ainsi que leurs origines, (3) de développer de nouvelles formulations de saucissons secs à teneurs réduites en sodium et en acides gras saturés, et (4) d’étudier les transferts d’eau et sel et de développer une isotherme de sorption spécifique pour le saucisson sec. L’étude de l’effet d’une réduction directe combinée a mis en évidence la difficulté de fabriquer des saucissons secs à teneurs réduites en sel et en matière grasse animale, sans modifier les évolutions physicochimiques et biochimiques. Une identification des composés volatils odorants de saucissons secs de haut de gamme a permis de montrer que l’aromatisation par l’ail et le poivre noir pouvait être un levier technologique permettant d’améliorer la qualité aromatique des saucissons secs allégés en sel et en matière grasse animale. L’impact de l’aromatisation et d’une substitution partielle combinée du sel par le chlorure de potassium et du gras de bardière de porc par l’huile de tournesol oléique sur les propriétés physicochimiques, les réactions biochimiques et les attributs sensoriels de saucissons secs, a été étudié. Cette étude a montré le rôle important de l’aromatisation qui agit en introduisant des molécules aromatiques qui rehaussent l’acceptabilité des produits par les consommateurs, en tant qu’exhausteur de la perception du goût salé et aussi, sur les processus fermentaires qui vont conditionner l’aspect et la texture finale du produit. La substitution partielle combinée est une solution efficace pour conserver au mieux la qualité organoleptique des saucissons, en permettant, d’une part, d’éviter les défauts texturaux et sensoriels liés aux modifications physicochimiques, protéolytiques et lipolytiques générés par une réduction directe combinée, et d’autre part, d’améliorer l’arôme du produit en rehaussant les niveaux d’oxydations lipidique et protéique. L’étude des transferts d’eau et de sel a mis en évidence une migration du sel vers le cœur du saucisson, et a permis de déterminer des valeurs de diffusivité apparente de l’eau en surface de ces produits. Il a été montré qu’une forte réduction en matière grasse réduisait la diffusivité de l’eau à la surface du saucisson. Une isotherme de sorption spécifique permettant de prédire l’aw en fonction des teneurs en eau, en lipides et en sel a été construite en adaptant un modèle de Ross établi pour la gélatine salée et grasse. / Because of public health problems, the food industry must lower sodium and animal fat contents in all food products, therefore in cured meat products. During dry-fermented sausage manufacture, a combined reduction both in salt and animal fat contents may induce microbial safety problems and textural and aroma defects due to physical-chemical and biochemical changes. On account of that, this work of thesis aims (1) to investigate the impact of a direct reduction on the salt and animal fat contents on the physical-chemical and biochemical evolutions in the products, (2) to identify the aromatic compounds responsible for the aroma of dry-fermented sausage, and their origins, (3) to develop new nutritionally-improved formulations of dry-fermented sausages with less sodium and saturated fatty acids, and (4) to study the impact of lipid and sodium chloride contents on water transfers in dry-fermented sausages and to build a specific sorption isotherm curve for dry sausages. The study of the effect of a combined direct reduction highlighted the difficulty of manufacturing sodium-reduced fat-reduced dry sausages, without affecting the physical-chemical and biochemical evolutions. Identification of odorous volatile compounds of high quality dry sausages showed that flavouring, especially garlic and black pepper, could be a good solution for improving the aromatic quality of salt-reduced fat-reduced dry-fermented sausages. The impact of flavouring and of a combined salt and animal fat replacement by potassium chloride and oleic sunflower oil, respectively, on physical-chemical properties, biochemical reactions and sensory attributes of dry-fermented sausages was then studied. This specific study showed the crucial role played by flavouring which introduces aromatic molecules that enhance the product acceptability by consumers, which acts as an enhancer of the saltiness perception and which improves the product appearance and texture by boosting the fermentation process. Consequently, the combined partial substitution is an efficient solution to preserve at best the organoleptic quality of the products, allowing, on one hand, avoiding the textural and sensory defects related to physical-chemical, proteolytic and lipolytic modifications induced by a combined direct reduction, and on the other hand, enhancing the product aroma by increasing the levels of lipid and protein oxidations. The study on water and salt transfers highlighted a salt diffusion towards the dry sausage core, and made it possible to determine values of apparent water diffusivity at the sausage surface. We demonstrated that a strong reduction in animal fat content significantly lowered the water diffusivity value at the product surface. A specific sorption isotherm curve based on a modified Ross model was built, allowing dry-fermented sausages water activity to be calculated as a function of water, fat and salt contents. Saucisson sec Sel Sodium Matière grasse animale Réduction directe Substitution partielle Composés volatils odorants Aromatisation Acceptabilité Transferts d’eau et sel Diffusivité de l’eau Isotherme de sorption Dry-fermented sausage Salt Sodium Animal fat Direct reduction Partial substitution Odorous volatile compounds Flavouring Acceptability Water and salt transfers Water diffusivity Sorption isotherm curve
98	Dr. Eleine Mad Jacobsson, Madeleine January 2021 (has links) Dr. Eleine Mad är Madeleine Jacobsssons talesperson för dom vetenskapliga och paranormala upptäckter som uppstår i hennes världar. Hon beskriver innehåll, teknik och estetik utifrån ett kategoriseringssytem där konsten delas upp som olika typer av komponenter och därefter avkodas dessa allteftersom. För att förstå intuitionens inblandning i arbetsprocessen omförvandlas den till tre separata roller av en Sökare, Samlare och Myntare. Med rollerna försöker jag beskriva på vilka sätt som intuitionen är till gagn eller av förödelse för det konstnärliga arbetet. Sagan om M handlar om en grodlik karaktär, Delop, som lämnar sin hemplanet för att uppsöka andra världar. I sitt sökande hittar Delop ett folkslag vars syn och levnadssätt skiljer sig från hennes erfarenheter av “verkligheten” såsom hon lärt sig att överleva i den. / Dr. Eleine Mad is Madeleine Jacobsson's spokesperson for the scientific and paranormal discoveries that arise in her worlds. She describes content, tecniques and aesthetics based on a categorization system where art is divided into different types of components and then decoded as they go. To understand the intuition's involvement in the work process, it is transformed into three separate roles by a Seeker, Collector and a Myntare(In swedish language the one who is a "myntare" -is verbally declaring a concept or term). With these roles I try to describe in what ways intuition is beneficial or devastating to the artistic work. The story of M is about a frog-like character, Delop, who leaves the home planet to seek out other worlds. In her search, Delop finds a world whose views and lifestyles differ from her experiences of "reality" as she learned to survive in it. / <p>Recorded sound and image material of the presentation is available for private use.</p> mjjgkjacb longing desire pang aj worlds shark genital symbol female sexuality worlds content the tale of M Doctor M mad life artifact animals figures emotional states red existentialism epicenter dog mythology folk beer whistle closeness aversions seeker collector myntare stagnation hibernation intuition sausage soup majdalakdemlsmikopa Delop Cow Lice snake hare sheep ödel oktor threat antipathy empathy fear performance function allow belief clitoral heroes monsters pink components situation dual nature euphoria bic-pens reality violence desert sea AQB brain holistics social codes self fairy tale space blue horse hell gotland dizzying flourish anthropomorphic jewels death plaster spiders commit survive frog whale bear purpose communication wild fascination animal incomparable monster ugly disturbed perspective marauder green symbolism who suffer anger reverence gods recast transformation yellow pry entrance interest alternative insignificant rigid position of power as disease real added disgusting wake up doubt mourn pray images horror plants rock stop mjjgkjacb längtan åtrå pang aj världar haj världsallt könssymbol kvinnlig sexualitet världarnas innehåll sagan om M Doktor M mad livet artefakt djur figurer känslomässiga tillstånd röd existentialism epicentrum hund mytologi folköl vissla närhet aversioner sökare samlare myntare stagnation dvala intuition korvsoppa majdalakdemlsmikopa Delop Ko Löss orm hare får Ödel Oktor hot antipati empati rädsla föreställning funktion tillåta tro klitorala hjältar monster rosa världar komponenter situation dubbla natur eufori bic-pennor verkligheten våld öken hav A.Q.B hjärna holistisk sociala koder självet sagorymd blå häst helvete Gotland vimmelkantig florera antropomorf juveler döden plåsterspindlar vägvisare begå överleva groda val björn syfte kommunicering vild fascination djurisk makalös vidunder ful störd perspektiv marodör grön symbolism vem genomlida ilska vördnad gudar omstöpt sammandrabbningar transformation gul bända ingång intresserar alternativ oväsentlig stel maktposition som sjukdom verkligt tillsatt äcklig vakna tvivla sörja be urbilder skräck växter rock stopp Arts Konst

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