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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.
1

Etude d'un nouveau procédé de fractionnement des co-produits de fabrication de jambon sec et des propriétés physico-chimiques et fonctionnelles des extraits et raffinats / Study of a new fractionation method of by-products from dry-cured ham manufacture and physico-chemical and functional properties of the extract and raffinate

Foret, Sylvain 16 December 2011 (has links)
Le coproduit de fabrication de jambon sec est issu de l'opération de désossage de la cuisse de porc parée, salée, séchée et affinée. Il est constitué à plus de 85 % d'os et de tissus associés (cartilages, ligaments, tendons). Le concassage au broyeur à marteau permet d'homogénéiser le coproduit en morceaux de taille inférieure à 8 cm (> 90 % compris entre 40 et 80 mm). La composition chimique de la matière sèche du mélange (77 ± 3 % de MS) est de 33 ± 5 % en protéines (89 % de collagène, 14 % de protéines hydrosolubles, 6 % d'acide aminés libres), 31 ± 3 % en lipides (triglycérides : 70 % ; diglycérides : 3,5 % ; acides gras libres : 11 % ; saturé/insaturé : 0,87 ; 24 % C16 :0 ; 13 % C18 :0 ; 2 % C16 :1 ; 38 % C18 :1 ; 4 % C18 :2) et 26 ± 4 % de matière minérale (phosphate de calcium 88 % ; NaCl 9 %). L'extraction aqueuse des lipides et des protéines du coproduit est étudiée en contacteur agité. Le raffinat solide est séparé par filtration à chaud sous forme de granulat et la matière grasse entraînée est séparée par décantation à froid. L'étude de l'influence des principaux facteurs de l'extraction liquide/solide (temps de contact : 30 à 90 min, température : 40 à 90°C ; ratio eau/coproduit : 4 à 10) grâce à la réalisation d'un plan d'expérience met en évidence les effets de la solubilisation et la coagulation des protéines sur l'entraînement des lipides et leur décantation sous forme de matière grasse. Mis en oeuvre à l'échelle pilote (64 kg de coproduit de jambon sec concassé, 207 kg d'eau, 30 min à 90°C en contacteur agité), le procédé de fractionnement aqueux conduit par filtration centrifuge et séchage à un granulat stable (rendement : 59 % ; matière minérale : 41 % ; protéines : 43 % ; lipides : 16 %), source de phosphate de calcium (95 % de la matière minérale) et de gélatine ou de colle d'os (88 % de protéines de nature collagénique). La fraction matière grasse décantée (rendement : 24 % ; lipides : 93 % ; triglycérides : 75 % ; diglycérides : 4 % ; acides gras libres : 7 % ; saturé/insaturé : 0,82 % ; 37 % C16 :0 ; 15 % C18 :0 ; 2 % C16 :1 ; 44 % C18 :1 ; 8 % C18 :2) présente les mêmes caractéristiques physicochimiques que le saindoux, avec une odeur proche de celle du jambon sec (19 COV aromatiques identifiés présents dans les arômes majoritaires de jambon). La fraction protéines solubilisées, obtenue sous forme de lyophilisat après concentration de la phase aqueuse (rendement : 8 % ; protéines : 52 % dont 29 % d'acides aminés libres ; matière minérale : 29 % dont 90 % NaCl, lipides : 3 %), contient aussi des glucosaminoglycanes sulfatés (GAGs : 3,4 %). Ces caractéristiques de composition, associées à ses propriétés épaississantes et gélifiantes, adhésives et stabilisantes d'émulsion, font de cette fraction minoritaire du procédé de fractionnement aqueux du coproduit de jambon sec, un extrait aux multiples applications à forte valeur ajoutée (source de peptones pour la culture de champignons et de levures, adhésif et liant naturel, ingrédient de formulation alimentaire nutracétique et cosmétique). / The ham production by-product comes from the deboning of dressed, salted, dried and refined pork leg. It consists of more than 85% of bone and associated tissues (cartilage, ligaments, tendons). Hammer mill crushing allows homogenizing the by-product into pieces smaller than 8 cm (> 90% between 40 and 80 mm).Dry matter chemical composition of the blend; (77 ± 3% DM) is 33 ± 5% protein (89% collagen, 14% of watersoluble proteins, 6% free amino acid), 31 ± 3% lipids (triglycerides: 70% diglycerides: 3.5%; free fatty acids: 11%; saturated / unsaturated: 0.87; 24% C16: 0; 13% C18: 0; 2% C16: 1; 38% C18: 1; 4% C18: 2) and 26 ± 4% mineral matter (calcium phosphate 88%, 9% NaCl). Lipids and proteins aqueous extraction of the by-product is studied in an agitated contactor reactor. The solid raffinate was separated by hot filtration to an aggregate and the fat is separated by cold decantation.The study of the influence of main factors of the liquid / solid extraction (contact time: 30 to 90 min, temperature: 40 to 90 °C; ratio water / by-product: 4 to 10) through the implementation of an experimental design, highlights the effects of proteins dissolution and coagulation on lipid output and decantation as fat matter.By pilot scale implementation (64 kg of crushed by-product of dry-cured ham, 207 kg of water, 30 min at 90 ° C in agitated contactor), the aqueous fractionation process leads, by centrifugal filtration and drying, to a stable aggregate (yield: 59%; mineral matter: 41%; protein 43%; lipids: 16%), source of calcium phosphate (95% of the mineral) and gelatin or bone glue (88% collagenous protein).The decanted fat fraction (yield: 24%; lipids: 93%; triglycerides: 75%; diglycerides: 4% free fatty acids: 7%; saturated / unsaturated: 0.82%; 37% C16: 0; 15% C18: 0; 2% C16: 1; 44% C18: 1; 8% C18: 2) has the same physicochemical characteristics as lard, with an odor similar to that of dry-cured ham (19 identified aromatic VOC part of ham main flavors). The solubilized protein fraction, obtained as a lyophilized extract after concentration of the aqueous phase (yield: 8%; protein: 52% with 29% of free amino acids; mineral matter: 29%, with 90% NaCl, lipids: 3%), also contains sulfated glycosaminoglycans (GAGs: 3.4%). These composition characteristics, associated with its thickening and gelling properties, adhesive and stabilizing for emulsion, transforms this minor fraction of the aqueous fractionation process of the dry-cured ham byproduct, in an high added value multiple applications extract (source of peptones for culture for fungi and yeasts, a natural and binding adhesive, ingredient for food nutraceutic and cosmetic formulation).
2

LCA to support decision-making in layout designs

Gomes, Victor Emmanuel, Barba Junior, Durval João de, Gomes, Jefferson de Oliveira, Grote, Karl-Heinrich 28 September 2017 (has links) (PDF)
Introduction The economic impact of environmental regulations in the manufacturing sector and the increasing costs of primary resources have pressured companies wishing to obtain competitive advantages to seek ways to rationalize these resources, either through changes in products specifications or in manufacturing process. These actions depend on solutions that should consider the limits set out in the interdependencies between economic, environmental and social areas, which comprise the so-called sustainability tripod. In this case, the guiding principle for decisions should follow the approach of sustainable development. For this purpose, a proper performance indicators evaluation of processes is a great step to improvement actions and decision making for modifications. Continuous improvement approaches and support of mathematical tools, such as the Discrete Event Simulation (DES) have been used for identifying waste on the shop floor and for cost analyses for manufacturing optimization (Standridge et al. 2006). One of the advantages resulting from the application of DES in corporations is its capability to include the impact of randomness in a system. All the dynamics and the non-deterministic nature of the parameters eliminate the use of static tools such as spreadsheets for solving many line design problems. Furthermore, all commercial simulation software provides detailed animation capabilities. The animation of the manufacturing process and flow can help engineers to visually detect problems or bottlenecks and also to test out alternate line designs. For this reason, the DES may be applied to generate requirements and sustainable systems specifications for manufacturing. However, the analyses results performed by using DES are not sufficient for the joint assessment of impacts on the three dimensions of sustainability (Johansson et al. 2010; Kuhl & Zhou 2009; Joschko et al. 2009). A tool widely used in the academic environment and by corporations to calculate pollutant emissions rates in the product life cycle is Life Cycle Assessment (LCA). This can supplement cost assessments performed with DES in the production process phase. This work discusses the combined use of DES with LCA to analyze production resources utilization in manufacturing systems. Towards this end, it seeks through a case study to analyze this joint use in decision-making for purchasing forklifts, according to sustainable premises.
3

LCA to support decision-making in layout designs

Gomes, Victor Emmanuel, Barba Junior, Durval João de, Gomes, Jefferson de Oliveira, Grote, Karl-Heinrich January 2012 (has links)
Introduction The economic impact of environmental regulations in the manufacturing sector and the increasing costs of primary resources have pressured companies wishing to obtain competitive advantages to seek ways to rationalize these resources, either through changes in products specifications or in manufacturing process. These actions depend on solutions that should consider the limits set out in the interdependencies between economic, environmental and social areas, which comprise the so-called sustainability tripod. In this case, the guiding principle for decisions should follow the approach of sustainable development. For this purpose, a proper performance indicators evaluation of processes is a great step to improvement actions and decision making for modifications. Continuous improvement approaches and support of mathematical tools, such as the Discrete Event Simulation (DES) have been used for identifying waste on the shop floor and for cost analyses for manufacturing optimization (Standridge et al. 2006). One of the advantages resulting from the application of DES in corporations is its capability to include the impact of randomness in a system. All the dynamics and the non-deterministic nature of the parameters eliminate the use of static tools such as spreadsheets for solving many line design problems. Furthermore, all commercial simulation software provides detailed animation capabilities. The animation of the manufacturing process and flow can help engineers to visually detect problems or bottlenecks and also to test out alternate line designs. For this reason, the DES may be applied to generate requirements and sustainable systems specifications for manufacturing. However, the analyses results performed by using DES are not sufficient for the joint assessment of impacts on the three dimensions of sustainability (Johansson et al. 2010; Kuhl & Zhou 2009; Joschko et al. 2009). A tool widely used in the academic environment and by corporations to calculate pollutant emissions rates in the product life cycle is Life Cycle Assessment (LCA). This can supplement cost assessments performed with DES in the production process phase. This work discusses the combined use of DES with LCA to analyze production resources utilization in manufacturing systems. Towards this end, it seeks through a case study to analyze this joint use in decision-making for purchasing forklifts, according to sustainable premises.
4

Sustainable Structural Design

Danatzko, Joseph M. 03 September 2010 (has links)
No description available.

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