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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

Méthanisation de marc de raisin. Caractérisation et optimisation du procédé et des prétraitements. / Anaerobic digestion of grape pomace. Characterization and optimization of the process and the pretreatments

El Achkar, Jean 30 May 2017 (has links)
La digestion anaérobie représente un élément clé dans la dynamique de développement durable contribuant à la valorisation verte des déchets organiques sous forme de biogaz et d'engrais. Dans le cadre de ce travail de thèse franco-libanais, nous cherchons à valoriser le marc de raisin, déchet majeur et principal sous-produit issu de la viniculture, par la digestion anaérobie, afin de générer de l’énergie dite verte sous forme de méthane. Dans un premier temps, le potentiel méthane du marc de raisin est démontré, validant notre biomasse végétale comme source potentielle d’énergie. Des informations détaillées sur les productions maximales de méthane à partir du marc entier, des pulpes et des pépins, séparément, sont obtenues en mode batch à 37 °C. La faisabilité technique du procédé est alors validée suite à une extrapolation au mode continu. De plus, des essais d’acclimatation du digesteur continu à la température moyenne de la vallée de la Bekaa (25 °C) permettent de simuler et d’adapter le système au milieu libanais. D’autre part, nous avons mené une caractérisation bio-physico-chimique de différents cépages de marcs de raisins en provenance de différentes régions viticoles. La diversité du contenu lignocellulosique et du potentiel méthanogène des substrats choisis a été mise en évidence. Une corrélation négative existe, en particulier, entre le potentiel méthane et les teneurs en lignine et en cellulose. Afin d’intensifier la production de méthane, le dimensionnement des digesteurs anaérobies en mode continu est optimisé en déterminant un optimum de fonctionnement pour une charge appliquée de 3,7 kg DCO m-3 j-1 et un temps de séjour de 20 jours. Enfin, nous évaluons les effets d’une variété de prétraitements (congélation, traitement alcalin, traitement acide, ultrasons et champs électriques pulsés) sur la production de méthane et sur la biodégradabilité des fractions. Le couplage du traitement alcalin à 10% NaOH avec la congélation à -20 °C s’avère être le meilleur procédé d’intensification. / Anaerobic digestion is considered to be a crucial part of a sustainable development strategy, contributing to the green valorization of organic waste as biogas and fertilizers. As part of this doctoral thesis, we explored the valorization of grape pomace, the major waste and main by-product of winemaking, by anaerobic digestion, to generate green energy in the form of methane. Firstly, the methane potential of grape pomace is demonstrated, validating our vegetal biomass as a potential source of energy. Detailed information on the maximum production of methane from whole pomace, pulps and seeds are obtained in batch mode at 37 °C. The technical feasibility of the process is then validated following an extrapolation to the continuous mode. Moreover, the acclimation of the continuous digester at the average temperature of the Beqaa valley (25 °C) allowed to simulate and adapt the current system to the Lebanese environment. On another note, we carried out a bio- physico-chemical characterization of different grape varieties from different wine-growing areas. The diversity of the lignocellulosic content and the methane potential of the selected substrates was highlighted. A negative correlation exists, in particular, between the methane potential and the lignin and cellulose fractions. In order to intensify methane production, we conducted an optimization of anaerobic digesters dimensioning in continuous mode by determining an optimum of operation for an applied load of 3.7 kg COD m-3 d-1 and a residence time of 20 days. Finally, we evaluated the effects of a variety of pretreatments (freezing, alkaline treatment, acid treatment, ultrasounds and pulsed electric fields) on the methane production and the biodegradability of lignocellulosic fractions. The coupling of the alkaline treatment using 10% NaOH with freezing at -20 °C seems to be the best intensification process.
2

The Effects of Agricultural Waste-Based Compost Amendments in Organic Pest Management

Stephenson, Gregg T 01 June 2019 (has links) (PDF)
Soil-borne pests and pathogens, such as Verticillium dahliae, can devastate a wide range of annual and perennial crops. Current management options for organic production are limited and sustainable management of pathogens, weeds, and arthropods is important for staying profitable and reducing the use of harmful chemicals. Organic soil amendments play an important role in supplying some of the nutritional needs of vegetable crops and improving soil structure, while also contributing to pest control. The objective of this research was to determine the effects of grape and olive-based composts on soil pathogen load, arthropod communities, and weed biomass and diversity. Field experiments were conducted in both organic and conventionally grown bell pepper (Capsicum annuum L.) systems during the summer growing season of 2018 on the Cal Poly campus in San Luis Obispo, California. Four different organic amendment treatments were tested including: olive based compost, grape based compost, dairy manure compost, and plant waste compost. Abundance of the fungal pathogen Verticillium dahliae was assessed from composite soil samples collected at several time points throughout the growing season. Olive, grape, and plant waste composts all displayed significant reduction of V. dahliae abundance between two to eight weeks post application of treatment when compared to the control. Insufficient evidence was found correlating farm management type with V. dahliae abundance after adjusting for treatment and time. Total dry weed biomass was assessed after one month of unhindered growth. The organic amendments tested appeared to alter weed species composition but not overall biomass though no significant differences were found. The soil arthropods symphylans and collembolans were sampled throughout the growing season, significant trends in population were found over time but not across treatments. This research demonstrates how agricultural waste-based compost amendments have potential as tools in pest management.
3

Extraktion av polyfenoler från pressrester av röda vindruvor / Extraction of polyphenols from red grape pomace

Haidarian, Behroz, Lidborg, Christina January 2011 (has links)
Antioxidanter är kemiska ämnen som är kapabla till att förhindra oxidation av andra molekyler. Dessa ämnen återfinns i djur- och växtriket och tycks ha en skyddande effekt på cellvävnad genom att motverka skadliga oxidativa reaktioner. Antioxidanter används bland annat industriellt som tillsater i livsmedel och andra produkter i syfte att förhindra oxidativ degradering och bibehålla näringsvärdet i livsmedel. I vindruvor återfinns höga koncentrationer av naturliga antioxidanter, främst i form av fenoliska ämnen. På grund av att vinindustrin bidrar till stora mänger avfall, främst i form av druvrester, är det önskevärt att hitta en effektiv metod för att återvinna fenoliska antioxidanter från avfallet.I detta arbete användes lösningsmedel-extraktion för att extrahera fenoliska ämnen från pressrester av röda vindruvor av varianten Tempranillo. Syftet var att uvärdera effekterna av extraktionsmetod, typ av lösningsmedel, extraktionstemperatur samt extraktionstid på fenol-innehåll och antioxidant aktivitet i extrakten. Två typer av extraktionsmetoder jämfördes; Soxhlet-extraktor och direkt-kontakt-extraktion (DCE), samt tre olika lösningsmedel; en blandning av etanol och vatten (1:1), ren etanol samt etyl acetat. Koncentrationen av fenoliskt innehåll i extrakten erhölls med hjälp av Folin-Ciocalteu's metod, och antioxidant aktivetet med FRAP (Ferric reducing ability of plasma) metoden.Utifrån erhållna data kunde det ses att extraktion med en blandning av etanol och vatten (1:1) som lösningsmedel gav högst fenolisk koncentration och antioxidant aktivitet för alla testade parametrar, medans etyl acetat gav de lägsta värdena. Soxhlet-extraktorn visade sig vara den bästa metoden då den gav högre värden i extrakten jämfört med DCE metoden. För DCE metoden kunde det ses att en extraktionstid på 2½ timmar vid 55 grader var mest optimalt då etanolbaserade lösningsmedel användes. / Program: Högskoleingenjörsutbildning i kemiteknik
4

Ultrasound Assisted Extraction Of Phenolics From Grape Pomace

Ozcan, Evren 01 January 2006 (has links) (PDF)
Grape pomace is a by-product of wineries. It is one of the most potent antioxidant sources due to its high phenolic content. In this thesis study, ultrasound assisted extraction of phenolic compounds from Merlot grape pomace has been studied. The effects of sonication time, subsequent extraction time in shaking water bath at 45&deg / C and composition of the solvent on extraction efficiency and recovery of phenolics were studied by response surface methodology. Folin-Ciocalteu colorimetric method was used to analyze effects of process parameters on the total phenolic content of the extracts. The best recovery (47.2 mg gallic acid equivalents of total phenolics per g of dried grape pomace) was obtained using 30 % aqueous ethanol and applying 6 minutes of sonication followed by 12 minutes of shaking in water bath at 45&deg / C.
5

Možnosti mikrobiální degradace a využití odpadů z potravinářských výrob / Prospects of Microbial Degradation and Waste Utilization from Food Processing Industry

Illková, Kateřina January 2012 (has links)
This work deals with the problem of microbial degradation of the waste materials from food industry. This work is focused on the production of technological significant enzymes producing by microorganisms, which were able to use the waste as a sole carbon source. In the first part of this work, the attention was focused on the production of pectolytic enzymes. This part was made within study interships in Slovak Academy of Sciences, department of Glycomics in Bratislava. The grape pomace as the waste form winegrowing was used as a sole carbon source for microbial growth and enzymes production. The production of pectolytic enzymes was tested on this waste. After screening the most suitable microorganisms was chosen with the highest production of polygalacturonase activity. Produced enzymes were isolated by extraction techniques, purified and then identified proteomically. The aim of the second part of this work was the waste water treatment containing lipids and lipolytic enzymes. The reason was the cooperation with the company constructing grease traps. The characterization of supplied commercial preparations was the subject of this work and the other reason was the characterization of conditions for lipases secreting by microorganisms, identification of microorganisms present in the commercial preparation and testing of new microbial cultures for the development of new preparation for the grease traps.
6

Use of Naturally Occurring Anthelmintics to Control Gastrointestinal Parasites in Small Ruminants

LeShure, Shirron Nicole 16 September 2014 (has links)
No description available.
7

Integrated Process Design and Techno-Economic Analysis of A Grape Pomace Biorefinery

Jin, Qing 09 September 2020 (has links)
Grape pomace (GP) is one of the most abundant and underutilized fruit-derived wastes. GP is generated during winemaking, occupying over 60% of the total solid winery wastes. GP may cause serious environmental problems if it is not properly handled. On the other hand, it is rich in valuable compounds that are worthy of recovery. Although research has been working on GP upgrading, the utilizations are limited to producing a single product (e.g., grape seeds oil or polyphenol powders), which leads to large volumes of secondary wastes left. Therefore, the goal of this study is to develop an integrated process for the comprehensive utilization of GP by the production of multiple value-added products and evaluate its economic feasibility at a commercial scale. First, the chemical composition of different industrial GPs was analyzed to lay the foundation for the process design. Based on the analyzed chemical composition, an integrated process was developed to produce grape oil, polyphenols, and biofuels from GP. In this process, GP was extracted by hexane to produce oil, followed by aqueous ethanol solution extraction to obtain polyphenols. The solid residue rich in structural carbohydrates was then pretreated by alkali to partially remove lignin and enzymatically hydrolyzed to produce monomer sugars. The produced sugars were used as feedstock to produce acetone, butanol and ethanol (ABE) through anaerobic fermentation. Under the optimized conditions, the process was able to produce 71.9 g crude oil, 322.8 g crude polyphenols (equivalent to 72.6 g gallic acid), and 20.7 g ABE from 1 kg dry GP. Besides the valuable products, the process co-generated a large amount (50% of input GP biomass) of secondary waste, which is rich in lignin. Therefore, we further converted the secondary waste to biochars and evaluated their potential application in water purification by removing lead (Pb) from contaminated water. Based on the results, the produced biochar showed a high Pb adsorption ability (134 mg/g), with 66.5% of lead removal achieved within the first 30 min. Experimental and modeling results indicated that both physisorption and chemisorption mechanisms were involved in the Pb adsorption of the biochar. Finally, techno-economic analysis was conducted to evaluate the economic feasibility of the integrated processing of GP into oil, polyphenols, and biochar at an industrial scale. The results showed that compared with generating of single product or dual products, the integrated process aiming to produce multiple products had the best economic performance with the net present value (NPV), internal rate of return (IRR), and payback period of $135.0 million, 47.5%, and 1.8 years, respectively. Sensitivity analysis showed that plant capacity and polyphenol selling price had major impacts on process economics. Therefore, a suggestion for implementing this integrated process is to invest more in the polyphenol production and purification process to generate high-quality polyphenols with a high selling price and running the plant with a large capacity. Overall, we explored a novel integrated process that aims to produce multiple value-added products to increase the economic gain for the wine industry, and at the same time, potentially reduce the environmental burdens caused by GP disposal. / Doctor of Philosophy / During wine making, a large amount of solid waste is generated, and the major one is called grape pomace (GP). GP is mainly consisted of grape skins, seeds, and some stems. Normally, GP is discarded as waste; however, if it is not handled properly, GP may cause serious damages to the environment such as contaminating soil and stream water. On the other hand, GP has valuable compounds that could be recovered for other applications. Previous researchers used GP to produce a single product, which still leads to a large amount of components not used. Therefore, the aim of the current study is to design a process to comprehensively utilize GP to produce multiple value-added products. The developed process can produce grape seed oil, polyphenols, and biofuels from GP. The solid residue generated from the designed process was further converted into biochar, which can be used as an excellent adsorbent to remove lead (Pb) from contaminated water. Based on the economic model results, the developed process to convert GP into grape seed oil, polyphenols, and biochar could be a promising investment at an industrial scale. Generally speaking, various valuable products were obtained from low value GP waste, which could not only reduce the potential environmental problems caused by waste disposal, but also provide different value-added products for food, pharmacy, chemical, and energy industries.
8

Les composés phénoliques des raisins : étude du potentiel qualitatif et des procédés émergeants d'extraction / The phenolic compounds of grapes : study of qualitative potential and emerging processes of extraction

El Darra, Nada 21 January 2013 (has links)
Ce travail porte sur l’amélioration de l’extraction des composés phénoliques à partir des raisins tout au long de la chaîne de la vinification en rouge. La qualité des vins rouges est en grande partie déterminée par les composés phénoliques. Parmi les composés phénoliques, les anthocyanes, qui sont responsables de la couleur, et les tanins, à l’origine de la sensation d’astringence. Pour augmenter la quantité des composés phénoliques présents dans le vin, un développement des procédés permettant d’améliorer la diffusion des composés phénoliques durant la vinification en rouge doit être mis en jeu. Nous avons entamé notre étude par un suivi de la maturité phénolique des raisins rouges appartenant à différentes parcelles de la société château KSARA localisées dans la vallée de la Békaa tout en se servant des méthodes Glories (1&2) et ITV. Quant à l’amélioration de l’extractibilité des composés phénoliques durant la vinification en rouge, différents prétraitements ont été appliqués dans le but d’améliorer la diffusion de ces composés. Parmi ces procédés, les technologies suivantes ont été abordées dans notre étude: les électrotechnologies (CEP), les ultrasons, le chauffage modéré, le traitement enzymatique, la macération préfermentaire à froid et la thermovinification. Ces techniques permettent d’endommager ou de fragiliser les membranes et/ou parois cellulaires facilitant ainsi la libération du contenu cellulaire vers le milieu extérieur. Les cinétiques d’extraction des composés phénoliques ont pu être modélisées par le modèle empirique de Peleg et le modèle cinétique simplifié afin d’estimer les rendements d’extraction. De plus, dans ce travail, l’accent a été mis sur les propriétés antiradicalaires et antimicrobiennes des composés phénoliques extraits de différentes variétés de raisins fournis par la société Château KSARA. Pour valoriser les co-produits de la vinification, le chauffage ohmique pulsé (COP) a été appliqué sur le marc du raisin dans le but d’améliorer l’extraction de ses composés phénoliques. L'optimisation du choix de la date des vendanges et l'amélioration des procédés d’extractions des composés phénoliques durant la vinification en rouge, pourraient nous conduire à élaborer un vin d'une meilleure qualité. Ce travail étant effectué, il sera intéressant comme projet à venir de valider ces différents pré-traitements à grande échelle pour une perspective d’application industrielle. / This study focuses on improving the extraction of phenolic compounds from grapes throughout the chain of red winemaking. The quality of wine is mainly determined by the phenolic compounds. From these phenolic compounds, the anthocyanins, which are responsible of the color and tannins, the responsible of the astringency. In order to increase the amount of phenolic compounds present in wine, a development of methods used to improve the extraction of phenolic compounds during the red vinification should be discussed. We began our study by using two methods Glories (1&2) and ITV to monitor the phenolic maturity of red grapes grown in the vineyards in the province of Bekaa-Château KSARA S.A.L. Whereas for the improvement of the extractibility of phenolic compounds during the vinification, different pre-treatments were applied in order to ameliorate the diffusion of these compounds. Among these process, the following technologies were discussed in our study: the electrotechnologies (PEF), the ultrasound, the moderate heat treatment, the enzymatic treatment, the cold maceration and the thermovinification. These techniques are able to weaken the cell walls and facilitate the diffusion of grape’s phenolic compounds during vinification. Peleg’s equation and the simplified kinetic model were shown to be suitable for describing the extraction kinetics for phenolic compounds and for the estimation of the extraction yield of polyphenols. Furthermore, in this study, the antiradical and antimicrobial activities of phenolic compounds extracted from grapevine varieties of Château KSARA-Bekaa-Lebanon were analyzed. To valorize the by-products of the vinification, the pulsed ohmic heating (POH) was applied on the grape pomace in order to ameliorate the extraction of the phenolic compounds. The optimization of the choice of the harvesting date and the amelioration of the extraction of phenolic compounds during the red vinification, will conduce to elaborate a high quality of wine. After this study, it will be interesting to validate the different pre-treatments at large scale for a perspective of an industrial application.
9

Aproveitamento dos subprodutos de vinificação da uva Bordô (Vitis labrusca) para obtenção de pigmentos com propriedades funcionais / Use of vinification byproducts of Bordo grape (Vitis labrusca) to obtain pigments with functional properties

Souza, Volnei Brito de 04 March 2013 (has links)
O objetivo deste trabalho foi produzir pigmentos em pó a partir dos subprodutos de vinificação da uva tinta, variedade Bordô (Vitis labrusca), através da secagem em spray dryer utilizando maltodextrina como agente carreador. Foram estudados os efeitos das condições de processo sobre algumas propriedades físico-químicas, além da estabilidade e da atividade biológica do material obtido. Extratos etanólicos das cascas e sementes da uva foram obtidos e concentrados até um terço do volume inicial. Este extrato foi então misturado com o agente carreador maltodextrina 10 DE nas concentrações de 10, 20 ou 30% e atomizado em spray dryer, com vazão de alimentação de 44 mL/min e temperaturas do ar de entrada de 130, 150 ou 170°C, num total de nove ensaios. Além disso, foi obtida uma amostra de extrato concentrado liofilizado, sem a presença do agente carreador, para efeito de comparação. Avaliou-se o rendimento do processo de atomização; e para as amostras obtidas determinou-se o teor de umidade, retenção de antocianinas, higroscopicidade e solubilidade em água, a fim de verificar a influência das condições de processo sobre essas características. Estas amostras também foram avaliadas quanto à morfologia, distribuição do tamanho de partículas e isotermas de sorção de umidade. Todas as amostras obtidas (atomizadas e liofilizada) foram avaliadas quanto à cor instrumental, espectroscopia de infravermelho, estabilidade durante a estocagem, presença de compostos bioativos (fenólicos, flavonóides, antocianinas e proantocianidinas), além de atividade antioxidante, antimicrobiana e de inibição da arginase de Leishmania. As condições de processo avaliadas (temperatura de secagem e concentração de agente carreador) tiveram forte influência nas características estudadas. O teor de umidade, a retenção de antocianinas, a morfologia e o tamanho das partículas, foram bastante influenciados pela temperatura de secagem e pela concentração de agente carreador, enquanto que a higroscopicidade sofreu maior influência da concentração de agente carreador. Esse parâmetro também apresentou grande influência nas isotermas de sorção de umidade das amostras. Não houve grande interferência do processo de secagem na composição química do material obtido, evidenciada pelos espectros de infravermelho. Quanto à avaliação da estabilidade durante a estocagem, foi observado que as amostras contendo maltodextrina conservaram mais as antocianinas e a cor, quando comparadas com as amostras sem carreador e os extratos líquidos, indicando, que o processo de secagem e a presença do carreador, promoveram um efeito protetor aos compostos e sua cor. Todas as amostras apresentaram altos teores de flavonóides totais, antocianinas, proantocianidinas e elevados valores de atividade antioxidante variando de 314,06 a 441,04 µmolesTE/g de extrato seco pelo método DPPH e de 993,32 a 1138,68 µmolesTE/g de extrato seco pelo método FRAP. Apresentaram atividade antimicrobiana principalmente contra Staphylococcus aureus e Listeria monocytogenes. Além disso, tiveram grande capacidade de inibir a enzima arginase de Leishmania com porcentagem de inibição variando de 54,60 a 83,43%. Os resultados encontrados sugeriram que o processo de secagem em spray dryer com maltodextrina, dos extratos obtidos dos subprodutos da uva Bordô, produziu pós com diversas características interessantes, como baixa higroscopicidade, alta solubilidade e estabilidade, além de grande potencial biológico. Tais resultados evidenciam que este subproduto da indústria vinícola pode ser aproveitado como fonte natural de ingredientes funcionais. / The aim of this work was to produce powder pigments from grape byproducts of Bordo variety (Vitis labrusca) by spray drying using maltodextrin as carrier agent. The effects of process conditions on some physicochemical properties, stability and biological activity of the product were studied. Ethanol extracts were obtained from grape pomace (skins and seeds) and concentrated to one-third the initial volume. This extract was then mixed with the carrier agent 10 DE maltodextrin at concentrations of 10, 20 or 30% and atomized in a spray dryer, with feed flow rate of 44 mL/min and inlet drying air temperatures of 130, 150 or 170°C a total of nine tests. In addition, a sample of freeze-dried concentrated extract without carrier agent was obtained for comparison. It was evaluated process yield and the samples obtained were initially evaluated for moisture content, anthocyanins retention, hygroscopicity and solubility in water, in order to verify the influence of process conditions on these characteristics. These samples were also evaluated for morphology, particle size distribution and moisture sorption isotherms. All samples (spray-dried powders and freeze-dried extract) were evaluated for instrumental color, infrared spectroscopy, stability during storage, presence of bioactive compounds (phenols, flavonoids, anthocyanins and proanthocyanidins) plus antioxidant activity, antimicrobial activity and inhibition of Leishmania arginase. Process conditions evaluated (inlet drying air temperature and carrier agent concentration) had a strong influence on the characteristics studied. The moisture content, anthocyanin retention, morphology and particle size of the samples were strongly influenced by drying temperature and carrier agent concentration while the hygroscopicity suffered greater influence of the carrier agent concentration. The concentration of carrier agent also had great influence on the moisture sorption isotherms of the samples. There was no significant interference of the drying process on the chemical composition of the material evidenced by infrared spectroscopy. Regarding the evaluation of stability during storage, it was observed that the samples containing maltodextrin, retained much more anthocyanins and original color when compared with the sample without a carrier or liquid extracts, indicating both, the drying process and the presence of carrier, promoted a protective effect to the compounds and its color. All samples showed high levels of flavonoids, anthocyanins, proanthocyanidins and high levels of antioxidant activity ranging from 314.06 to 441.04 µmolTE/g of extract (dry weight), by DPPH and 993.32 to 1138.68 µmolTE/g of extract (dry weight) by FRAP method. Most samples showed antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes. Moreover, had great ability to inhibit the enzyme arginase of Leishmania with inhibition percentage ranging from 54.60 to 83.43%. The results suggest that the drying process of Bordo grape pomace extracts in a spray dryer with maltodextrin, produced powders with various interesting characteristics such as low hygroscopicity, high solubility and stability, and large biological potential. This shows that this byproduct of wine industry can be used as a natural source of functional ingredients.
10

NÍVEIS DE INCLUSÃO DE SILAGEM DE BAGAÇO DE UVA NA DIETA DE CORDEIROS EM FASE DE TERMINAÇÃO / LEVELS OF INCLUSION OF GRAPE POMACE SILAGE IN THE DIET OF LAMBS UNDER FATTENING

Maciel, Marcus Brocardo 06 November 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present study aimed to evaluate the performance, carcass characteristics, the fatty acid profile and meat quality of lambs fed increasing levels of grape pomace silage replacing alfalfa. We used 24 not castrated Texel lambs, with an average weight of 24.5 kg and a mean age of 100 days, randomly distributed in a completely randomized design with four treatments and six replications. The treatments consisted of increasing levels of grape pomace silage (SBU) of 0%, 15%, 30% and 50% on a full ration. Observed effect of inclusion level of SBU consumption of dry matter, crude protein, total digestible nutrients (P <0.01) decreased as the inclusion level of SBU increased. A quadratic effect of inclusion levels of SBU on consumption of lipids (CEE) (P <0.01) was observed. The use of neutral detergent fiber and feed conversion was not affected by inclusion level of dietary SBU. The inclusion level of SBU in the diets affected (P <0.01) the average daily weight gain, which decreased with increasing dietetic SBU, presenting average values of 268, 251, 235 and 213g for levels: 0 , 15, 30 and 50% of SBU inclusion in the diet, respectively. There was no effect (P> 0.05) in the level of inclusion of SBU carcass characteristics, weights of body components and weights and proportions of commercial cuts of lambs. It was observed (P <0.01) that the level of inclusion of SBU has promoted an increasing of linoleic acid (C18: 2n6c) concentration in Longissimus dorsi muscle. It was also observed increase in the content of polyunsaturated fatty acids (P <0.05). Moreover, the ratio between polyunsaturated fatty acids to saturated (P: S) was improved to values of 0.179, 0.192, 0.226 and 0.227 (P <0,05), respectively as the SBU was increased. However, the increase of SBU promoted increasing (P <0.01) of the content of omega 6 (n-6) in relation to the content of omega 3 (n6: n3) presenting ratios of 3.16, 4.85, 6.39, 6.82, respectively for levels of 0, 15, 30 and 50% of SBU tested. The softness, cholesterol, pH and chemical composition of muscle tissue were not affected (P> 0.05) by the level of SBU. As a result, it can be concluded that the grape pomace silage is an alternative source of nutrients for lambs and can be used as a substitute for good quality hay, for providing satisfactory performance, without carcass characteristics and body components alteration, producing a healthier meat for human consumption due to the increase of polyunsaturated fatty acids content. / O presente estudo teve por objetivo avaliar o desempenho, as características da carcaça, o perfil de ácidos graxos e a qualidade da carne de cordeiros alimentados com níveis crescentes de silagem de bagaço de uva em substituição à alfafa. Foram utilizados 24 cordeiros machos, não castrados, raça Texel, com média de peso vivo de 24,5 kg e idade média de 100 dias, distribuídos aleatoriamente em um delineamento inteiramente casualizado com quatro tratamentos e seis repetições. Os tratamentos foram constituídos por níveis crescentes de silagem de bagaço de uva (SBU) de 0%, 15%, 30% e 50% numa ração completa. Observou-se efeito do nível de inclusão de SBU no consumo de matéria seca, proteína bruta, nutrientes digestíveis totais (P<0,01) que decresceram à medida que se aumentou o nível de inclusão de SBU. Houve efeito quadrático de níveis de inclusão de SBU sobre o consumo de extrato etéreo (CEE) (P<0,01). O consumo de fibra em detergente neutro e a conversão alimentar não foram afetados pelo nível de inclusão de SBU na dieta. O nível de inclusão de SBU nas dietas influenciou (P<0,01) o ganho de peso médio diário, que diminuiu com o aumento de SBU na dieta, apresentado valores médios de 268, 251, 235 e 213g para os níveis de: 0, 15, 30 e 50% de inclusão de SBU na dieta, respectivamente. Não foi observado efeito (P>0,05) do nível de inclusão de SBU nas características de carcaça, pesos dos componentes corporais e pesos e proporções dos cortes comerciais da carcaça dos cordeiros. Foi observado efeito (P<0,01) do nível de inclusão de SBU no percentual do ácido linoleico (C18:2n6c) depositado no músculo Longissimus dorsi, havendo incremento deste ácido com o aumento do nível de inclusão de SBU. Também se observou aumento no teor de ácidos graxos poli-insaturados (P<0,05) e relações entre ácidos graxos poli-insaturados e saturados (P:S) mais favoráveis, de 0,179; 0,192; 0,226 e 0,227 (P<0,05), respectivamente, na medida em que se aumentou a inclusão de SBU. No entanto, o aumento de SBU promoveu incremento (P<0,01) no teor de ácidos graxos ômega 6 (n-6) em relação ao teor de ômega 3 (n6:n3) apresentando razões de 3,16; 4,85; 6,39; 6,82, respectivamente para os níveis de 0 a 50% de SBU testados. A maciez, o colesterol, o pH e a composição centesimal do tecido muscular não foram influenciados (P>0,05) pelo nível de SBU. A silagem de bagaço de uva é uma fonte alternativa de nutrientes para cordeiros, podendo ser utilizada em substituição a forragens de boa qualidade, pois proporcionou desempenho satisfatório, não alterou as características da carcaça e componentes corporais e produziu uma carne mais saudável ao consumo humano por aumentar o teor de ácidos graxos poli-insaturados.

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