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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.
91

Sulfuração negra em carne enlatada : efeito dos parâmetros de processamento e da embalagem / Sulphide black in canned meat : effects of processing and packaging parameters

Dantas, Fiorella Balardin Hellmeister, 1975- 08 April 2014 (has links)
Orientador: Marise Aparecida Rodrigues Pollonio, Sílvia Tondella Dantas / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T00:03:06Z (GMT). No. of bitstreams: 1 Dantas_FiorellaBalardinHellmeister_D.pdf: 14117695 bytes, checksum: 4532bc383166205549d251332c6b58f3 (MD5) Previous issue date: 2014 / Resumo: Neste trabalho estudaram-se os parâmetros promotores da sulfuração negra em produto cárneo em conserva na busca de estratégias tecnológicas para reduzir ou evitar sua ocorrência. Na primeira parte do trabalho foram avaliados os parâmetros de processamento e embalagem que promovem a sulfuração negra em carne bovina em conserva (corned beef) acondicionada em latas de aço determinando-se assim quais são os aspectos a serem controlados na condição atualmente utilizada nas plantas de processamento do produto. Em seguida avaliou-se a composição das manchas negras formadas e a exposição do aço base, que permitiram verificar que a presença da mancha de sulfuração negra estava sempre associada à exposição metálica, principalmente na região de recravação onde há maior solicitação mecânica do verniz. Esse fato indicou que apesar da possibilidade de permeação dos íons de enxofre pelo verniz, para a reação ocorrer há necessidade de falha na camada de verniz em qualquer região da lata. Verificou-se também que as manchas eram compostas de aminoácidos e outros componentes do produto, assim como carbono e oxigênio, mostrando a influência do processo de acondicionamento do produto na ocorrência da sulfuração negra. Foram avaliadas também as possibilidades de adição de zinco à formulação do produto e do verniz epóxi fenólico alumínio, as quais permitiram verificar que o tratamento térmico de 125 ºC por 65 min combinado com concentração de zinco de 10 mg.kg-1 foi o que apresentou menor incidência de sulfuração na tampa e indicaram que a utilização de verniz interno epóxi fenólico com alumínio mais 6% de zinco é uma opção na prevenção da reação de sulfuração negra. Por fim, através de solução modelo, avaliou-se a influência da adição de agente quelante (EDTA ¿ sais do ácido etilenodiamino tetracético) no produto. Os resultados obtidos na quarta e última parte deste trabalho mostraram que a adição de EDTA à solução catalisadora foi eficiente quanto à prevenção da reação de sulfuração negra, porém há necessidade de estudos futuros para determinação da concentração adequada e avaliação de sua influência na ação do nitrito de sódio em relação à cor e à segurança alimentar / Abstract: The present work studied the parameters that promote sulfide black in corned beef in order to find technological strategies to reduce or prevent its occurrence. Firstly, it was evaluated the packaging and processing parameters that promote sulfide black in corned beef and determined which aspects that should be controlled in the condition currently used in product processing plants. Then, it was evaluated the composition of the black spots and iron exposure which allowed to verify that the black stain was always associated with the metal exposure, since most of the cans exhibited stain along the double seam. This fact indicated that despite the possibility of permeation of sulfur ions through the lacquer to the reaction occurrence a fail in the coating layer is required in some can region. It was also verified that the black stain was comprised of amino acids and other components coming from the product, including carbon and oxygen, showing the effect of the packaging process in the occurrence of sulfide black. The influence of the addition of zinc in canned meat product and in the internal lacquer of the package was also evaluated to prevent the reaction. The results showed that the heat treatment of 125 ºC/65 min with zinc concentration of 10 mg.kg-1 presented the lowest incidence of spots in the lids, furthermore the results suggest the use of lacquer epoxy phenolic with aluminium and 6% of zinc as an option in the sulfide black prevention. Finally, using model solution it was evaluated the influence of EDTA (ethylenediaminetetraacetic acid salts) addition in canned meat product. Results suggest the use of EDTA as an option in the sulfide black prevention, but future studies using the product are necessary to determine the appropriate concentration and assessment of their influence on the action of sodium nitrite in relation to color and food safety / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos
92

Mejora del proceso productivo de una línea de conservas de caballa para reducir el tiempo en el llenado del coche en una empresa pesquera

Ortiz Castro, Gino Charles January 2015 (has links)
La investigación se desarrolló en una empresa productora y comercializadora de todo tipo de conservas a base de diversos pescados, dentro de su oferta tienen diversas presentaciones, una de ellas son las conservas de caballa. Precisamente en esta línea de producción se presentaba el problema a resolver: excesivo tiempo muerto en el traslado manual del producto, mediante coches, de la línea a la autoclave. Este proyecto se enfocó específicamente en mejorar el proceso productivo, reduciendo tiempos en la producción de la elaboración de la caballa, implementando una paletizadora y modificando el coche a estibar que pasa a la autoclave. Con esta mejora, se ha logrado reducir en un 93% el llenado de coche de autoclave. The research was conducted at a producer and marketer of all kinds of canned fish using diverse within its range they have different presentations, one of which is canned mackerel. Precisely in this production line was presented the problem to solve: excessive downtime in the manual transfer of the product by car, line the autoclave. This project is specifically focused on improving the production process, reducing time in the production of mackerel developing, implementing and modifying palletizing stow the car passing the autoclave. With this improvement, it has been reduced by 93% the car filled autoclave.
93

Caractérisation et écologie microbienne de lignes de production de conserves / Characterization and microbial ecology of canned food process lines

André, Stéphane 16 June 2015 (has links)
Si les flores contaminantes représentent la plupart du temps, dans les conserves, un risque industriel aujourd'hui maitrisé, la flore d'altération, de par sa résistance importante à la température, continue à constituer une cause de pertes économiques majeures. Pourtant cette dernière restait cependant peu caractérisée. En s'appuyant sur les travaux réalisés ces dernières années au sein de l'unité de microbiologie EMaiRIT'S du CTCPA (unité d'Expertise dans la Maitrise du Risque Industriel en Thermorésistants Sporulés du Centre Technique de la Conservation des Produits Agricoles), les principaux objectifs de cette thèse ont été (i) d'identifier et caractériser, en vue de sa maitrise ultérieure, la flore d'altération sporulante (ii) d'identifier l'origine de ces flores dans les conserveries et enfin (iii) de déterminer des moyens de maitrise.Pour cela, un état des lieux des bactéries sporulées d'altération des conserves a été effectué avec la collaboration de 122 conserveries sur plus de 10 ans en France. Cette caractérisation des espèces altérantes a permis l'élaboration d'un outil de biologie moléculaire (SporeTraQTM) afin d'identifier rapidement ces germes ou de pouvoir les détecter au sein d'une population complexe. En parallèle, l'amélioration de la connaissance de la thermorésistance de ces espèces, principale caractéristique de la flore sporulante, a été menée. A ce paramètre, il a été associé une relation avec la chimio résistance des spores. Identifiée, nous avons cherché à localiser cette flore d'altération au sein des usines à l'aide de plusieurs campagnes de prélèvements sur différents légumes. Au final, la flore spécifique du procédé de fabrication des conserves a été identifiée, caractérisée et localisée en vue d'améliorer la maitrise du risque microbien soit par une maitrise des contaminations et/ou un nettoyage plus performant (localisation au niveau d'étapes unitaires, efficacité de molécules sporicides) soir par un barème optimisé (en relation avec la thermorésistance). De plus, ce travail a été conduit au sein d'une approche bénéfice/risque représentant le futur de l'évolution des procédés agro-alimentaires associant amélioration de la qualité nutritionnelle et maintien de la maitrise sanitaire. Cette thèse s'appuie sur 5 publications de rang A. / Microbial contaminants of safety concern represent most of time, in canned food, an industrial risk which is well mastered. However, the spoilage flora, due to its high heat resistance, is responsible for major economic losses. Nevertheless, these bacteria remained poorly characterized. Based on the works realized during last 10 years within the EMaiRIT'S unit of microbiology of the CTCPA (expertise unit of the French Technical Center of the Preservation of Food, focused on Management of Industrial Risk liked to Heat Resistant Spores), the main objective of this thesis were: i) to identify and to characterize, with the aim of its later control, the spoilage spore forming bacteria florae ii) to identify the origin of these florae in canning factories and finally iii) to determine ways of control.For that purpose, a current inventory of spore forming bacteria in spoiled canned food was made with the cooperation of 122 canning factories over more than 10 years in France. This characterization of the spoilage species allowed the elaboration of a molecular biology tool (SporeTraQTM) for quick identification of these germs or their detection within a complex population. In parallel, the improvement of the knowledge about the heat resistance of these species, main characteristic of the spores, was led. In addition, the chemical resistance of spores was investigated. When identified, we tried to localize these spores on canning factories lines, with several sampling plans, on various vegetables. At the end, the specific spore forming bacteria related to the industrial canning process was identified, characterized and localized, allowing to improve the microbial risk control either by a more efficient cleaning, and through optimized process schedules. Furthermore, this work was driven within a benefic / risk approach representing the future of the food-processing evolution with improvement of the nutritional quality and the preservation of the sanitary control.This thesis leans on 5 publications of rank A.
94

Estudio de prefactibilidad para la instalación de una planta procesadora de conservas de ciruela (Spondias purpurea) en almíbar

Barboza-Carnero, Ximena-Briset, Villasís-Serquén, Fiorella-Alessandra January 2016 (has links)
El objetivo principal de este proyecto es determinar la viabilidad tecnológica, económica, financiera, de mercado y social para la instalación de una planta procesadora de conservas de ciruela (Spondias purpurea) en almíbar para el consumo nacional. / The main objective of this project is to determine the economic, financial, social and market viability to install a factory of canned plum (Spondias purpurea) in syrup for national consumption. / Trabajo de investigación
95

Rhythmic Consonance and Dissonance in Eckhard Kopetzki’s Works for Solo Percussion: Topf-tanz and Canned Heat

Hampton, Walter Ellis 12 1900 (has links)
This study examines the compositional devices Eckhard Kopetzki used to create consonance and dissonance throughout his two works for solo percussion, Topf-Tanz and Canned Heat. By manipulating meter, ostinato, syncopation, polyrhythm, note values and overlapping figures, Kopetzki creates high levels of musical tension and release that shape phrase structure and large-scale form. After a discussion of rhythmic consonance and dissonance, and specific rhythmic devices, both works are considered in detail, illuminating the composer’s compositional language. Topf-Tanz is an exploration of contrasting ideas: the rhythmic and the lyrical, the call and the response, the loud and the soft. It is manifested first in the opposition of antecedent and consequent phrases and second in the overlapping of contrasting metric ideas, which creates prolonged rhythmic dissonance. Canned Heat, on the other hand, is composed through a process of continuing melodic variation. Throughout the piece, melodic motives are prolonged and abridged, creating both delay and acceleration to cadential figures. In contrast to these melodic ideas, each phrase is concluded with stark and syncopated rhythmic punctuations. Topf-Tanz and Canned Heat share Kopetzki’s creation of rhythmic consonance and dissonance. Most notably is the overlapping of contrasting metric ideas between the two hands, and highlighting this contrast through the use of two contrasting instrument families; skin and metal. On the large scale, both works progress from of a place of rhythmic consonance to one of dissonance.
96

High pressure destruction kinetics of bacterial spores in low acid food at elevated temperatures

Shao, Yanwen, 1967- January 2008 (has links)
No description available.
97

The California canning asparagus industry under government sponsored controls

Lucot, Weldon Walter 01 January 1947 (has links) (PDF)
This study is an analysis of the attempts to control the marketing of asparagus by federal license under the Agricultural Adjustment Act in 1934 and 1935; by state license under the California Marketing Agreement Act in 1936 and 1937; by proration program under the California Agricultural Prorate Act in 1938 to 1941; and by marketing orders under the California Agricultural Code from 1941 to 1945. Among the questions considered are the following: What was the economic position of the Asparagus Industry in 1934, when the programs were first instituted? What were the effects of some previous attempts at controlled marketing of asparagus? What types of controls were undertaken in the asparagus industry? What was the administrative setup and particularly the problem of the appropriateness of such controls in a "free enterprise" society?
98

Investigation Of Corrosion In Canned Chicken Noodle Soup Using Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS)

Wu, Yajun, Wu 29 December 2016 (has links)
No description available.
99

A methodology for the simulation of non-isothermal and canned extrusion of metal powders using finite element method

Ramakrishnan, Ramanath I. January 1989 (has links)
No description available.
100

Menhaden (Brevoortia tyrannus): utilization as a potential food resource

Long, Kristine A. January 1985 (has links)
Thermally processed menhaden products were evaluated as potential food products. Nine canned menhaden products judged to be satisfactory in pilot studies were canned or pasteurized and evaluated by a six member semi—trained panel. Panelists scored product characteristics of menhaden products and commercially canned tuna in oil, tuna in water and mackerel. Three canned menhaden products were incorporated in "pizza" sauce and in fish salad recipes that were scored for preference by consumer panelists. Objective measurements for drained weight and total fluid were recorded. Descriptive analysis of the nine canned menhaden products indicated that the dressed and filleted menhaden products were similar in the firmness, flakiness, chewiness, moisture, and fish flavor characteristics. Canned minced menhaden products were significantly different from the dressed and filleted fish products in the texture characteristics: firmness, flakiness and chewiness. Plots drawn for comparison of mean characteristic scores of each menhaden product and the three comparison products (tuna in oil, tuna in water, mackerel) indicated that the canned filleted menhaden in oil was judged by a semi—trained panel to be similar to the two commercially canned tuna products. Consumer preference scores for the menhaden products were significantly different from the scores for comparison products used in the pizza sauces and fish salads. The menhaden fish salads and the menhaden pizza sauce were scored lower. Objective measurements indicated that the use of an alum and citric acid brine increased percent weight loss and percent fluid loss. The minced menhaden product brined in alum and citric acid had the highest recorded percent weight loss and percent fluid loss. Pilot study and consumer preference panelists indicated that the alum and citric acid brine imparted a metallic aftertaste to the canned menhaden products. / Master of Science

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