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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.
111

Technologies for tissue preservation: the role of endogenous and exogenous antioxidants in preserving tissue function in chinook salmon, Oncorhynchus tshawytscha

Tuckey, Nicholas Pierre Lemieux January 2008 (has links)
The seafood industry is of considerable importance to both the New Zealand and global economies and therefore tissue preservation technologies that increase product quality and/or prolong shelf life have the potential to add significant value. Technologies for maintaining the viability of isolated tissues also have a wide range of other medical and industrial applications. This thesis examines the relationship between metabolic function, oxidation and cell death and the resulting stability of the non-viable tissues during long term storage in chinook salmon (Oncorhynchus tshawytscha) red and white skeletal muscle tissue. This research also looks at the role of the aquatic anaesthetic AQUI-S™, in which the active ingredient is isoeugenol (a lipid soluble antioxidant), and other antioxidant compounds in preserving metabolic function in viable tissues and tissue stability in nonviable tissues. Perfusion of salmon tails at 15℃ over 5 or 10 hours with oxygen saturated saline resulted in significant increases in protein and lipid oxidation (protein carbonyl and TBARS concentrations respectively) in the red muscle, but not the white muscle. The introduction of ascorbic acid and uric acid into the saline did not reduce the oxidation in the red muscle despite significantly increasing their respective concentrations in the tissue. This indicates the difficulties associated with attempting to extend tissue viability by delivering free oxygen to the tissue and also highlights the difference in susceptibility of the two muscle types to oxidation. Tail fillets from salmon harvested in both rested and exhausted physiological states using AQUI-S™, and fillets from exhausted salmon harvested without AQUI-S™, were exposed to air at 15℃ for up to 96 hours. Protein carbonyls increased in a roughly linear fashion over the entire 96 hours in all three groups. Both lipid peroxides (TBARS) and uric acid concentrations began to increase in the exhausted group after 30 hours. In contrast, no significant increases in lipid peroxides or uric acid was seen in the fillets from either group harvested using AQUI-S™. Vitamin E concentrations reduced slowly but did not change significantly despite the oxidation that was evident in the tissue. These processes also occurred in salmon tail fillets during storage at 6℃. The measurement of ATP related compounds provides an effective indicator of both the metabolic state of the tissue post-harvest and the quality. The breakdown of these compounds is also associated with the production of ammonia and hydrogen peroxide. Fresh rested salmon fillets had high concentrations of ATP and creatine phosphate, which were both depleted after 12 hours storage at 15℃. This indicates that cell viability lasted a number of hours following harvesting. These metabolites were depleted in exhausted fillets and metabolic potential appeared to be immediately compromised. The concentration of the taste enhancing compound IMP was significantly reduced in fresh rested tissue, but increased during storage, and was significantly higher than in exhausted tissues following 12 hours of storage at 15℃. This indicates that some properties of rested tissues may improve with limited storage times. The accumulation of uric acid - the metabolic end point for ATP related compounds - was also significantly reduced in rested tissue and increases in K-value were slowed. AQUI-S™ showed an ability to preserve tissue function through its anaesthetic action allowing tissue to be harvested in a rested state, and to reduce late stage lipid oxidation in stored salmon tail fillets. The antioxidant action of isoeugenol in salmon fillets may be mediated through its ability to chelate transition metals released during tissue degradation. This research shows that during reperfusion and during fillet storage there is a significant level of oxidative stress, which needs to be minimized while maintaining basic tissue metabolism to prolong tissue and cellular viability. The development of future technologies to preserve tissue viability may depend on the development of a synthetic oxygen carrying compound with properties similar to red blood cells. This may allow more control over oxygen delivery, potentially reducing the oxidative stress associated with high concentrations of free oxygen in solution. However, preserving cell viability will also require the maintenance of endogenous antioxidant function and there is also the potential to use iron chelating compounds including plant derived flavonoids to preserve non-viable tissues. Future research in these areas is necessary.
112

Avaliação do potencial antioxidante de coprodutos de indústrias de suco de uva e de vinho visando sua aplicação em linguiça de frango

Casagrande, Maira 05 June 2014 (has links)
CAPES / A busca por produtos naturais e os riscos para a saúde decorrentes do consumo de antioxidantes sintéticos incentivam a investigação para a descoberta de novas fontes potenciais de compostos bioativos. A produção de vinho e suco de uva geram grandes quantidades de coprodutos ricos em compostos fenólicos que podem ser utilizados como antioxidantes naturais. Este estudo teve como objetivo avaliar as melhores condições de extração de compostos bioativos, através de um planejamento fatorial fracionário 24-1, de um coproduto oriundo do processamento da indústria de sucos de uvas (BUS – Bagaço de Uvas Suco) e de um coproduto oriundo do processamento da indústria de vinhos (BUV – Bagaço de Uvas Vinho). E, após a determinação da melhor condição para ambos os coprodutos, avaliar a atividade antioxidante utilizando diferentes metodologias de quantificação, sendo que dentre as duas amostras (BUS e BUV), a que obtivesse maior potencial antioxidante, seria testada no processamento de linguiça frescal de frango com intuito de verificar a inibição da formação de malonaldeído em comparação ao antioxidante sintético ES (eritorbato de sódio). Para a extração dos compostos bioativos as variáveis independentes estudadas foram: tipo de coproduto (BUS ou BUV), temperatura do banho-maria (40 ou 60 °C), tempo de extração dos compostos bioativos (15 ou 45 minutos) e o tipo de solvente utilizado (acetona 80% ou etanol 80%). Os extratos dos coprodutos foram analisados em termos do conteúdo total de compostos fenólicos por Folin-Ciocalteu e atividade sequestradora do radical DPPH• (variáveis dependentes). A atividade sequestradora de radicais livres nos 16 testes gerados variaram 65-149 μmol Trolox.g-¹ e compostos fenólicos totais entre 18-35 mg GAE.g-¹ (equivalente ácido gálico). A análise de regressão linear mostrou que mais de 97% da variabilidade dos dados foi explicada pelo modelo gerado para a variável dependente atividade antioxidante e 93% para compostos fenólicos totais. Levando-se em conta os pontos ótimos de extração para BUS e BUV, fixaram-se extrações com acetona 80%, 60°C, durante 15 minutos para BUS e 45 minutos para BUV. Sob essas condições de extração, BUS apresentou: atividade antioxidante pelo método DPPH (IC50), ABTS•+, FRAP, e percentual de inibição do sistema de β- caroteno/ácido linoleico em valores de 349 μg.mL-1, 334 mmol TEAC.g-1, 151 mmol Fe²+.g-1 e 73%, respectivamente. Enquanto BUV resultaram em 489 μg.mL-1, 249 umol TEAC.g-1, 111 umol Fe²+.g-1 e 68%, respectivamente. As respostas do planejamento fatorial mostraram que BUS teve o maior teor de compostos fenólicos e atividade antioxidante quando comparados ao BUV, em suas melhores condições. Foram elaboradas quatro formulações de linguiça frescal de carne de frango: amostra controle (sem antioxidantes – T1), amostra contendo antioxidante sintético a 0,01% (T2), amostra contendo 2 mg.g-1 de extrato de BUS (T3) e uma amostra contendo 4 mg.g-1 de BUS (T4). Para a elaboração das linguiças com extrato de BUS, utilizou-se o extrato da melhor condição, determinada pelo planejamento fatorial (acetona 80%, 60°C, 15 minutos), sendo que os extratos foram evaporados e liofilizados. Os parâmetros físico-químicos e microbiológicos das formulações T1, T2, T3 e T4, resultaram em valores que estão em concordância com as legislações vigentes. A cor sofreu variações durante o tempo de armazenamento das linguiças frescais de frango, sendo que T3 e T4 foram os tratamento que tiveram maior ΔE e menores valores de L*. Os tratamentos T1 e T2 obtiveram maiores valores de a*, b* e C*. O pH decaiu, para as quatro formulações de linguiças, variando de 6,71 a 5,99, entre os tratamentos. Para medir a oxidação lipídica foi utilizada a metodologia TBARS. As amostras contendo BUS foram capazes de inibir a oxidação lipídica. No tempo de 8 dias de armazenamento a 4°C, em relação ao controle, T2 conseguiu inibir a formação de malonaldeído em 0,31%, enquanto que os tratamentos contendo 2 e 4 mg.g-1 de extrato liofilizado de BUS (T3 e T4) inibiram 55% e 73% respectivamente. / The search for natural products and the risk to human health due to consumption of synthetic antioxidants encourage research for the discovery of new potential sources of bioactive compounds. The production of wine and grape juice generates large amounts of pomace rich in phenolic compounds that can be used as natural antioxidants. The objective of this work was to evaluate the extraction of bioactive compounds from pomace of grape juice (BUS) and wine (BUV) industry using a 24-1 fractional factorial design. After the determination of the better extraction condition for both co-products, was determinate with the total antioxidant activity using different determination methodology, and among the two samples (BUS and BUV), which obtained the largest quantifications by these methodologies, would be tested in the processing of chicken sausage in order to verify the inhibition of formation of malondialdehyde compared to synthetic antioxidant ES (sodium erythorbate)The independent variables studied were grape fruit pomace (GJP) and grape wine pomace (GWP), both temperature (40 and 60°C), extraction time of compounds (15- 45 min), and solvent type (acetone and ethanol, 80%). Co-products extracts were analyzed in terms of the contents of TPC by Folin Ciocalteu and scavenging activity of the DPPH• radical. After determining the best extraction method of bioactive compounds in each pomace (GJP and GWP), we determined the amount of antioxidants required to decrease the initial concentration of DPPH at 50% (IC50), ABTS• radical scavenging activity, Ferric Reducing Antioxidant Power (FRAP), and inhibition percentage by autoxidation of the system of β-carotene/linoleic acid. The DPPH radical scavenging activity in the 16 tests ranged from 65-149 μmol Trolox.g-1, and the TPC from 18-35 mg GAE.g-1 (gallic acid equivalent). The statistical analysis explains the significance of the effects and coefficients of the model generated in terms of their antioxidant activities. The linear regression analysis showed that the model generated explain more than 93% of the data variability. Thus, for both pomaces, acetone 80% was the best solvent for the extraction of antioxidant compounds and the ideal extraction temperature was 60°C. However, the best extraction time for GJP was 15 min and for GWP, 45 min. Under these extraction conditions, GJP showed activity in the DPPH method (EC50), ABTS•+, FRAP, and inhibition percentage at 339 μg.mL-1, 334 μmol TEAC.g-1, 151 μmol Fe2+.g-1and 73%, respectively. The values for GWP were 489 μg.mL-1, 249 μmol TEAC.g-1, 111 μmol Fe2+.g-1 and 68%, respectively. The responses of the factorial design showed that GJP had higher contents of phenolic compounds and antioxidant activity than GWP in its better extractions conditions. Was formulated four different chicken meat sausages: control sample (without antioxidant – T1), sample containing synthetic antioxidant 0.01% (T2), sample containing 2mg.g-1 of GJP extract (T3) and a sample containing 4 mg.g-1 of GJP extract (T4), the GJP extract was utilized lyophilized and in your optimized condition according to the factorial design (acetone 80%, 60ºC, 15 minutos), and the extracts were route-evaporated and lyophilized. The physicochemical and microbiological parameters of all formulations resulted in values that are consistent with current laws. Was observed color variations during the storage period of fresh chicken sausages, treatments T3 and T4 had the highest ΔE and the smaller L * values. T1 and T2 treatments had higher values of a *, b * and C *. The pH showed a reduction for the four formulations of sausages, ranging from 6.71 to 5.99, between treatments. To measure lipid oxidation TBARS methodology was used. Samples containing BUS were able to inhibit lipid oxidation. At time 8 days of storage at 4 ° C, compared to the control, T2 could inhibit the formation of malonaldehyde 0.31%, while the treatments with 2 ad 04 mg.g-1 of lyophilized BUS extract (T3 and T4) inhibited 55% and 73% respectively.
113

Prodloužení skladovatelnosti chlazených rybích výrobků / Extending of shelf life of chilled fish products

PFLUG, Róbert January 2016 (has links)
This diploma thesis was focused on the possibilities of extending the shelf-life of fish products by dipping containing seven commercial additives. ANTIBAK, MIC STAB, Bakont, SEA-F75, Misocarine LR, SAFE A Plus and AMX liquid. The effectiveness of these substances on the extending of shelf-life was evaluated on the basis of tests of TVC (total viable count), level of fat and protein oxidation, determination of nutritional parameters of muscle, and finaly sensory analysis. Experimental species were 2 important commodities for the Czech aquaculture rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio). The project was divided into 6 sub-stages. During testing was the initial number of aditives (7) limited by stepwise selection for 2 preparations. Namely Bakont and AMX liquid, which were tested further on trout (filet with skin and scales) and carp (filets with skin without scales) chilled bulk and chilled packaged under vakuum. For trout was studied antimicrobial effect of dipping on eviscerated fish with the head with- or without gills. Treated trout fillets in bulk and vakuum-packed showed significantly less abundance of muscle mikroflora. In the case of carp fillets chilled bulk we can not say that the bath had influence on the CMP in meat. However, the combination of dipping and vakuum packaging was singnificantly different between the control and product Bakont. AMX liquid was not applied in this case in sufficient dose or in sufficient time to carp muscle. A positive finding is that the application of the aditives to the product "eviscerated trout with head" it does not matter, whether the gills are left in fish or not. However, in all cases the analysis of the presence of pathogens Escherichia coli, Salmonella spp. or Listeria monocytogenes were negative. From the results of sensory analysis can be concluded, that the substances contained in aditives are not reflected in the sensory properties of tested fish.
114

Avaliação de hidrolisados de caseína como antioxidantes em produtos cárneos e chocolate branco

Rossini, Karina January 2008 (has links)
Estudos recentes indicam que os peptídeos obtidos pela hidrolise enzimática da caseína podem apresentar atividades antioxidantes. Neste trabalho, previamente obteve-se os peptídeos através de hidrolise da caseína utilizando as enzimas Alcalase e Flavourzyme (4h, a 50ºC e pH 8), selecionando os que apresentaram as melhores características, in vitro, relativas à atividade antioxidante. A hidrolise enzimática utilizando a enzima Flavourzyme mostrou melhores resultados, com alto valor de proteína solúvel e conteúdo de aminoácidos livres, além de peptídeos de menor peso molecular do que com a Alcalase, como observado nas análises de cromatografia de permeação em gel e eletroforese em gel de poliacrilamida. Os peptídeos de caseína obtidos com a Flavourzyme também apresentaram melhores resultados utilizando o método ABTS na determinação da capacidade antioxidante. O hidrolisado obtido a partir da enzima Flavourzyme foi aplicado em produtos cárneos e em chocolate branco. Em produtos cárneos, os peptídeos de caseína (2.0%) inibiram, efetivamente, a peroxidação lipídica em carne moída (100%) e em carne mecanicamente separada de ave (CMS) (cerca de 20%) indicando que estes peptídeos podem ser utilizados nestes produtos, auxiliando na prevenção da formação de flavor desagradável e aumentando sua vida útil. Relativamente a sua aplicação em chocolate branco, esta adição teve o intuito de inibir escurecimento deste produto, fator considerado como limitante na sua vida-útil sendo conseqüência tanto de reações de escurecimento não enzimático quanto da oxidação de lipídeos. Os parâmetros que indicaram alteração lipidica e reações não enzimáticas foram mensurados em três diferentes amostras de chocolate branco: uma amostra com 0,2%, de manteiga de cacau, de antioxidante sintético Grindox 562, outra com 0,2%, de manteiga de cacau, dos peptídeos de caseína e a terceira amostra sem qualquer tipo de antioxidante. As amostras foram expostas a duas temperaturas diferentes: 20 ± 2 e 28 ± 2ºC. Os resultados das análises realizadas indicaram que as amostras armazenadas à temperatura de 20ºC apresentaram resultados significativamente melhores àqueles das amostras armazenadas à temperatura de 28ºC, relativos ao índice de acidez, à atividade de água, ao índice de peróxido, à cor e às substâncias reativas ao ácido tiobarbitúrico (TBARS), indicando melhor conservação deste produto. Também foi observado que a adição de quaisquer dos antioxidantes empregados não influenciou de forma significativa os resultados obtidos, evidenciandose assim, que o principal parâmetro responsável pelas alterações do chocolate branco em sua vida útil refere-se à temperatura de armazenamento a qual as amostras foram submetidas. / Recent studies indicate that peptides obtained by casein hydrolysis may have antioxidant activity. In this work, previous casein peptides were obtained by enzymatic hydrolysis using Alcalase and Flavourzyme (4h, at 50ºC and pH 8), selecting the ones that showed the best characteristics in vitro, related to the antioxidant activity. The enzymatic hydrolysis using Flavourzyme showed the best results, with higher soluble protein and free amino acid content and producing lower molecular weight peptides than Alcalase, as observed by gel permeation chromatography and polyacrylamide gel electrophoresis. Related to its application in meat products, casein peptides obtained with Flavourzyme also exhibited greater antioxidant capacity using the ABTS method. The casein hydrolyzed from Flavourzyme enzyme was applicated in ground beef homogenates, mechanically deboned meat (MDM) of poultry and white chocolate. In meat products, casein peptides (2.0%) effectively inhibited lipid peroxidation in ground beef homogenates (100%) and mechanically deboned meat (about 20%) of poultry. Casein peptides may be useful in meat processing as another naturally occurring antioxidant, helping to prevent off-flavor formation in meat products and increasing shelf life. In the use for white chocolate, the goal was to inhibit its browning, the main problems that limit the white chocolate’s shelf-life. Non-enzymatic browning reaction and lipid oxidation were involved directly in the browning of white chocolate. Thus, parameters which indicated fat alteration and non-enzymatic reactions were measured in three different samples of white chocolate. One sample with 0,2% of cocoa butter, with the synthetic antioxidant Grindox 562, other with 0,2% of cocoa butter, with the natural antioxidant and the third sample without any kind of antioxidant. The samples were exposed to two different temperatures: 20 ± 2 and 28 ± 2ºC. The results of the analysis made indicated that the samples stored at the temperature of 20ºC showed results significantly better to those samples stored at the temperature of 28ºC, related to the conservation of the white chocolate. Besides, the results indicated that the addition of any antioxidants employees has not influenced in a significant way the results obtained. Thus, it was evidenced that the main responsible parameter for the alterations of the white chocolate’s shelf-life is related to the storage temperature to which the samples were submitted.
115

Extraction, identification and antioxidant activity of the phenolic secondary metabolites isolated from the leaves, stems and fruits of two shrubs of the Ericaceae family / Extraction, identification et activité antioxydante des métabolites secondaires phénoliques isolés des feuilles, branches et fruits de deux arbrisseaux de la famille des Ericacées

Bujor, Oana-Crina 19 April 2016 (has links)
La myrtille et l’airelle rouge, deux arbrisseaux de la famille des Ericacées, sont consommées comme des aliments, boissons et suppléments alimentaires pour leur valeur nutritionnelle et leur richesse en polyphénols antioxydants. Dans les plantes, la qualité et la quantité de composés phénoliques sont influencées par les parties morphologiques de la plante à utiliser. En particulier, les composés phénoliques des végétaux exercent leur activité antioxydante dans la protection des lipides alimentaires et le compartiment gastrique a été proposé comme le site majeur pour le stress oxydatif lié au régime alimentaire. L’objectif général de cette thèse était d’étudier les variations saisonnières des composés phénoliques d’extraits de feuilles, branches et fruits de la myrtille et de l’airelle rouge ainsi que l’activité antioxydante de ces extraits. Pour cette étude, des extraits aqueux et hydroéthanoliques (fruits uniquement) des échantillons collectés en mai, juillet et septembre pendant les années 2013-2014 ont été obtenus par extraction assistée par microondes.Les analyses qualitatives et quantitatives par UPLC / MS des extraits de la myrtille ont montré la présence de dérivés de l’acide caféique et de l’acide p-coumarique et des glycosides de flavonols dans les feuilles tandis que des oligomères de flavanols étaient aussi présents dans les branches, et ce dans des quantités élevées. La thioacidolyse a révélé de faibles degrés de polymérisation (2-4) et l’(-)-épicatéchine comme unité principale des flavan-3-ols. Il existe une très bonne corrélation entre la Somme des Composés phénoliques par UPLC et la Teneur en Polyphenols Totaux ou l’activité antioxydante dans le test DPPH, excepté pour les feuilles du mois de mai. Ces dernières sont relativement riches en dérives de l’acide p-coumarique. Les effets de la saison apparaissent plus marqués pour les feuilles qui présentent une plus grande activité antioxydante et teneur en polyphénols en juillet et septembre. Ces paramètres sont optimaux en juillet pour les branches de myrtille. La période de de cueillette peut être définie en fonction des structures phénoliques désirées.Dans l’airelle rouge, la présence prédominante de monomères et oligomères de flavanols et de glycosides de quercétine a été identifiée dans toutes les parties morphologiques. Les proanthocyanidines contiennent la (+)-catéchine et la (-)-épicatéchine comme unités d'extension et terminale. De plus, la teneur en polyphénols totaux (méthode de Folin, UPLC) a montré une augmentation légère mais significative de mai à septembre pour les feuilles et les branches. Cette augmentation a été confirmée pour l'activité antioxydante dans le test DPPH pour les feuilles et les branches en 2014.L’activité antioxydante des extraits de myrtille et d’airelle rouge lors de l’inhibition de l’oxydation lipidique (accumulation de diènes conjugués) a été évaluée dans des conditions in vitro simulant la digestion. Tout d'abord, l'inhibition de l’oxydation lipidique a été conduite sur des émulsions huile de tournesol-dans-eau stabilisées par la sérum albumine bovine (BSA) ou des phospholipides d’œuf (PL), qui simulent l’état physique des lipides alimentaires lors de la digestion gastrique. L’oxydation a été initiée par la metmyoglobine, une forme de fer apportée par la viande rouge. Dans les deux modèles d’émulsions, les extraits aqueux des branches et des feuilles et l’extrait hydroethanolique de fruit de myrtille sont des inhibiteurs plus efficaces de l'oxydation lipidique durant la première phase de digestion (pH 5) que durant la seconde phase (pH 3). D’autre part, un extrait de feuilles de myrtille a été testé dans un modèle complet de digestion in vitro statique (étapes orale, gastrique et intestinale). L'oxydation lipidique, rapide lors de la l’étape gastrique (systèmes BSA et PL) et puis plus lente lors de l'étape intestinale (système PL), a été totalement inhibée par l'extrait de feuilles de myrtille. / Bilberry and lingonberry, two shrubs of the Ericaceae family, are consumed as food, beverage and dietary supplements due to their nutritional value and richness in antioxidant polyphenols. In plants, the quality and quantity of phenolic compounds are influenced by the parts of the plant to be used. In particular, plant phenolic compounds provide antioxidant activity in the protection of dietary lipids from oxidation and the gastric compartment has been proposed as a major site for diet-related oxidative stress. The aim of this thesis is to simultaneously assess the seasonal variations of phenolic compounds in leaves, stems, and fruits of bilberry and lingonberry extracts, as well as their antioxidant activity. For this study, aqueous and hydroethanolic (only fruits) extracts of bilberry and lingonberry samples collected in May, July and September during the years 2013-2014 were obtained under microwave-assisted extraction.In bilberry extracts, qualitative and quantitative analyses by UPLC/MS showed the presence of caffeoyl derivatives, p-coumaroyl derivatives, and flavonol glycosides in leaves whereas in stems, flavanol oligomers were additionally identified in significant amounts. Thioacidolysis revealed low degrees of polymerization (2-4) and (-)-epicatechin as the main flavan-3-ol unit. The sum of the phenolic compounds by UPLC was highly correlated with the Total Polyphenol Content and the antioxidant activity in the DPPH test for all the extracts except those of May leaves. The latter were relatively richer in p-coumaric acid derivatives. Seasonal effects were more marked for leaves which exhibited higher antioxidant activities and phenolic contents in July and September when these parameters were maximum in July for bilberry stems. The harvest period can be refined based on the desired phenolic structures. For lingonberry, the predominant presence of monomers and oligomers of flavanols and quercetin glycosides was found in all the morphological parts. Proanthocyanidins contain (+)-catechin and (-)-epicatechin as both extension and terminal units. The sum of the phenolic compounds by UPLC was less correlated with the Total Polyphenol Content and the antioxidant activity in the DPPH test than in bilberry. Furthermore, the total phenolic content (Folin method, UPLC) showed a slight but significant increase from May to September for both leaves and stems. This increase was confirmed for the antioxidant activity by the DPPH test for both leaves and stems in 2014.The antioxidant activity of bilberry and lingonberry extracts against lipid oxidation (formation of lipid-derived conjugated dienes) was evaluated under in vitro simulated digestion conditions. Firstly, the inhibition of lipid oxidation was performed using sunflower oil-in-water emulsions stabilized by bovine serum albumin (BSA) or egg yolk phospholipids (PL), both emulsifiers mimicking dietary components. Oxidation was initiated by metmyoglobin, a form of dietary iron from red meat. In both emulsion models, aqueous extracts from stems and leaves and the hydroethanolic fruit extract of bilberry proved to be more efficient inhibitors of lipid oxidation in the early phase of digestion (pH 5) than during the second phase (pH 3). Secondly, a bilberry leaf extract was tested in the inhibition of lipid oxidation in a complete static in vitro digestion model (oral, gastric and intestinal phases). The fast lipid oxidation in the gastric step (BSA and PL systems) and the slower lipid oxidation in the intestinal step (PL system) were totally inhibited by the bilberry leaf extract.
116

AVALIAÇÃO DA ATIVIDADE ANTIOXIDANTE E ANTIMICROBIANA DO EXTRATO DE SEMENTE DE CHIA E SUA APLICAÇÃO EM LINGUIÇA FRESCAL / EVALUATION OF ANTIOXIDANT AND ANTIMICROBIAL ACTIVITY OF CHIA SEED EXTRACT (Sálvia hispânica) AND ITS APPLICATION IN FRESCAL SAUSAGE

Scapin, Gabrielle 20 March 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present study had as object verify the antioxidant activity of chia seed extracts (Sálvia hispânica) and its antioxidant effect in pork sausage. First of all, it was held the chemical composition of the chia seed. It presented high dietary fiber content, protein and lipids and low moisture content. After that, it was elaborated hydroethanolic extracts by stirring, using different ethanol concentrations and temperatures. In the extracts obtained were performed analyzes to measure total phenolic compounds, total flavonoids and antioxidant activity in vitro through DPPH and FRAP methods. The extract obtained from stirring using ethanol 80% as solvent and 60ºC temperature, was the one that got the best antioxidants features, so, this one was applied in concentrations of 1%, 1,5% and 2% in pork sausages. To characterize the meat product, were held analyzes to measure pH, color, TBARS values and microbiological analysis. The sensorial analysis was evaluated by the test of acceptability with hedonic scale of seven points, and purchase intent test. The results obtained in the proximate composition, as well as in the microbiological analyzes to positive Staphylococcus coagulase, coliforms between 35ºC and 45ºC, Samonella sp e Clostridium sulfito products reducer are according to what is required by Brazilian law. The sausage pH showed an increase throughout time in storage. Regarding color, the product showed a staining tendency to browning. In the end of 28 days of storage, the TBARS values was 1,12 mg of MDA/kg to the control treatment (0% of chia extract). The chia seed extract did not present effects over the microbiological stability along the storage, measured by counting the total mesophilic aerobic microorganisms and psicrotrofics. The sensorial features stability was kept, showing good acceptability by consumers. Therefore, we can conclude that the chia seed extract (Sálvia hispânica) was able to inhibit the lipid oxidation of pork sausage, which suggests its applicability as a natural antioxidant source. / O presente estudo teve por objetivo verificar a atividade antioxidante de extratos de semente de chia (Sálvia hispânica) e seu efeito antioxidante em linguiça de carne suína. Primeiramente, foi realizada a composição química da semente de chia. A mesma apresentou alto conteúdo de fibra alimentar, proteína e lipídios e baixo teor de umidade. Após elaborou-se os extratos hidroetanólicos por agitação, utilizando diferentes concentrações de etanol e temperaturas. Nos extratos obtidos foram realizadas análises de compostos fenólicos totais, flavonóides totais e atividade antioxidante in vitro através dos métodos DPPH e FRAP. O extrato obtido através de extração por agitação utilizando etanol 80% como solvente e temperatura de 60oC foi o que apresentou as melhores características antioxidantes, então o mesmo foi aplicado nas concentrações de 1%, 1,5% e 2% em linguiças de carne suína. Para a caracterização do produto cárneo, foram realizadas análises de umidade, proteínas, cinzas, gordura e a cada sete dias foram realizadas as análises de pH, cor, índice de TBARS e análises microbiológicas. A análise sensorial foi avaliada através do teste de aceitabilidade com escala hedônica de sete pontos e teste de intenção de compra. Os resultados obtidos na composição centesimal, bem como nas análises microbiológicas para Staphylococcus coagulase positiva, Coliformes a 35 º C e a 45 º C, Samonella sp e Clostridium sulfito redutor dos produtos estão de acordo com o exigido pela legislação brasileira. O pH da linguiça apresentou um aumento ao longo do tempo de armazenamento. Com relação à cor do produto, este apresentou uma coloração com tendência ao escurecimento. Ao fim de 28 dias de armazenamento, os valores de TBARS foram de 1,12 mg de MDA/kg para o tratamento com 2% de extrato de chia e 1,60 mg de MDA/ kg para o tratamento controle (0% de extrato de chia). O extrato de semente de chia não apresentou efeito sobre a estabilidade microbiológica ao longo do armazenamento, avaliada pela contagem de micro-organismos aeróbios mesófilos totais e psicrotróficos. A estabilidade das características sensoriais foi mantida, demonstrando boa aceitabilidade pelo consumidor. Desta forma, conclui-se que o extrato de semente de chia (Sálvia hispânica) foi capaz de inibir a oxidação lipídica da linguiça de carne suína, sendo viável a aplicabilidade como uma fonte antioxidante natural.
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CARACTERIZAÇÃO FÍSICO-QUÍMICA, MICROBIOLÓGICA E COMPOSTOS BIOATIVOS DE FARINHAS DE CASCAS E BAGAÇO DE KIWI (Actinidia deliciosa) E APLICAÇÃO EM PATÊ / PHYSICHOCHEMICAL, MICROBIOLOGICAL CHARACTERIZATION AND BIOACTIVE COMPOUNDS OF KIWI (Actinidia deliciosa) PEEL AND POMACE FLOUR AND APPLICATION IN PÂTÉ

Soquetta, Marcela Bromberger 18 June 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pâté or paste is made up primarily of fats, proteins and water, being susceptible to deterioration reactions, such as lipid oxidation. Antioxidants are used to slow this processes, with the synthetic ones being more utilized, however, because they are safer, natural sources have been analyzed, like fruit residues, that are rich in phytochemicals while simultaneously provide an alternative to waste. Kiwi is a fruit know worldwide by its taste and high nutritional value. The transformation of these in flour is important do to volume reduction and perishability. The objective of this study was to determinate the bioactive compounds of flours of peel and pomace from two variations (Bruno and Monty) of kiwi (Actinidia deliciosa), unripe and ripe, and the application of the flour with the highest antioxidant activity in different concentrations in ham pâtés. To obtain the flour was used an oven at 35 ± 5 ºC, analytical mill and sieves for standardization of particle size. Analisys of chemical composition, pH determination, water activity, microbiological characterization, antimicrobial activity, determination of bioactive compounds, vitamin C, total phenolics, chlorophylls, total carotenoids, total flavonoids and antioxidant activity (DPPH and FRAP) were performed. According to the results, kiwi peel flour from the Bruno variety in the first stage of maturation was the sample with the highest antioxidant activity by the DPPH metod (72,04% of maxim activity) and with the highest level of total phenols (1262,34 mg GAE/100g), being therefore the flour chosen for elaboration of the pâtés, which followed the procedures described by Terra (1998). The ingredients were mixed in cutter for emulsification, packaging and pasteurization at 73 ºC in the interior of the mass. The formulations differ in relation to the antioxidant, them being: T1 standard, with addition of sodium erythorbate; T2 control, without antioxidant addition; T3, T4 and T5 with addition of natural antioxidant, kiwi peel flour (FCK) in different concentrations 0.5, 1.0 and 2.0%, respectively. After the product was finished, analysis of chemical composition, pH, color, lipid oxidation, DPPH, vitamin C, texture, microbiological and sensory analysis were performed. The ham pâtés were within the law requisites for chemical composition and microbiological stability, did not show oxidative changes during storage and showed good sensory acceptability for the concentrations of 0,5 and 1,0% of kiwi peel flour (FCK). The ham pâtés added with kiwi flour can be considered functional foods, having over 3 g of dietary fiber in every 100 g of pâté. Within the results was observed that the kiwi flours are characterized as an important source of bioactive compounds and dietary fiber, enabling its use as an ingredient in meat products. / O patê ou pasta constitui-se principalmente por gorduras, proteínas e água, sendo susceptível a reações de deterioração, como a oxidação lipídica. Os antioxidantes são utilizados para retardar estes processos, sendo que os sintéticos são mais utilizados. Entretanto, por serem mais seguros, tem-se analisado fontes naturais, como os resíduos de frutas, que são ricos em fitoquímicos, ao mesmo tempo em que fornecem uma alternativa para os desperdícios. O kiwi é um fruto mundialmente conhecido pelo sabor e alto valor nutritivo. A transformação destes em farinha é importante pela redução do volume e perecibilidade. O objetivo deste estudo foi à caracterização físico-química, microbiológica e compostos bioativos de farinhas de cascas e bagaço de Kiwi (Actinidia deliciosa), de duas variedades (Bruno e Monty), em dois estádios de maturação, e a aplicação da farinha, de maior atividade antioxidante, em diferentes concentrações, em patês de presunto, visando ação antioxidante e adição de fibra alimentar. Para a obtenção das farinhas utilizou-se estufa a 35°C (±5), moinho analítico e peneiras para padronização da granulometria. Foram realizadas as análises de composição centesimal, determinação de pH, atividade de água, caracterização microbiológica, atividade antimicrobiana, determinação de compostos bioativos, vitamina C, fenólicos totais, clorofilas, carotenoides totais, flavonoides totais e atividade antioxidante (DPPH e FRAP). Conforme os resultados, a farinha de casca de kiwi da variedade Bruno, no primeiro estádio de maturação, foi a amostra de maior atividade antioxidante pelo método DPPH (72,04% de atividade máxima) e a que contém o maior teor de fenólicos totais (1262,34 mg GAE/100g), sendo então a farinha escolhida para a elaboração dos patês, que seguiu os procedimentos descritos por Terra, (1998). Os ingredientes foram misturados em cutter para a formação da emulsão, embalagem e pasteurização a 73°C no interior da massa. As formulações diferenciaram em relação ao antioxidante, sendo elas: T1-padrão, com adição de Eritorbato de sódio; T2- controle, sem adição de antioxidante; T3, T4 e T5- com adição de antioxidante natural, farinha de casca de kiwi (FCK) em diferentes concentrações 0,5, 1,0 e 2,0%, respectivamente. Após o produto acabado foram realizadas as análises de composição centesimal, pH, cor, oxidação lipídica, DPPH, vitamina C, textura, análises microbiológicas e sensorial. Os patês de presunto se apresentaram dentro dos requisitos da legislação tanto para a composição centesimal quanto para estabilidade microbiológica, não apresentaram alterações oxidativas durante o armazenamento e boa aceitabilidade sensorial para as concentrações de 0,5 e 1,0% de farinha de casca de kiwi (FCK). Os patês de presunto adicionados de FCK podem ser considerados alimentos funcionais, visto que possuem mais de 3g de fibra alimentar em cada 100g de patê. Com os resultados observou-se que as farinhas de resíduos de kiwi caracterizam-se em importante fonte de compostos bioativos e fibra alimentar, e adicionadas ao patê de presunto, não alteram a qualidade físico-química e microbiológica, viabilizando a sua utilização como ingrediente em produtos cárneos.
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CULTURA STARTER PRODUZIDA EM MEIO DE CULTURA DE PLASMA SUÍNO E ANTIOXIDANTE NATURAL NA ELABORAÇÃO DO SALAME / STARTER CULTURE PRODUCED IN PORK PLASMA CULTURE MEDIUM AND NATURAL ANTIOXIDANT IN THE DRY FERMENTED SAUSAGE ELABORATION

Campagnol, Paulo Cezar Bastianello 24 January 2007 (has links)
This work aimed to produce and to apply in dry fermented sausage a lactic acid starter culture using a pork plasma culture medium and to evaluate the effect of two levels (0.5% and 1%) of hydroalcoholic extract of marcela (Achyrocline satureioides) in the security and quality of dry fermented sausages. In the first experiment, the microorganism Lactobacillus plantarum was fermented with control of pH, during 36 hours, under continuous agitation of 100 rpm, at a temperature of 37 (± 0.1ºC). After entering in the stationary phase the culture was lyophilizated and applied in dry fermented sausage, evaluating its influence in the microbiological, physico-chemical and sensorial characteristics. For comparative effects, were elaborated treatments without addition of starter culture and with addition of a commercial culture. In the second experiment, dry fermented sausages had been elaborated with 0.5% and 1% of hydroalcoholic extract of marcela and without extract, considered as control. The parameters of pH, water activity, colour and weight loss were evaluated during the manufacture of the dry fermented sausages. During the storage the TBARS values were determined and verified the sensorial acceptance. The microorganism Lactobacillus plantarum had a maximum growth of 9.82 Log UFC.mL-1, after 30 hours of fermentation and it presented 90.05% of survival to the lyophilization. The dry fermented sausages elaborated with the starter culture produced had presented a decrease on pH significantly faster and a lower water activity than the others treatments. Moreover, the microorganism Lactobacillus plantarum improved significantly the flavor of the dry fermented sausages. The marcela extract addition decreased (p<0.05) the TBARS values during the storage of the dry fermented sausages, compared with the control. The treatment with 1% of marcela extract showed a bigger lipid stability than that with 0.5%, however it presented a reduction (p<0.05) in the sensorial acceptance. The two marcela extract levels had not influenced the parameters of pH, water activity, colour and weight loss. Therefore, this study indicated that the pork plasma culture medium is an alternative in the commercial production of lactic acid bacteria and that the starter culture produced provided a dry fermented sausage with greater microbiological security and better sensorial acceptance. The hydroalcoholic extract of marcela decreased the lipid oxidation and the concentration of 0.5% did not modify the sensorial characteristics, being able, therefore, to be used in the elaboration of safer dry fermented sausages to the consumers. / Este trabalho teve por objetivo produzir e aplicar em salame uma cultura starter ácido láctica utilizando um meio de cultura de plasma suíno e avaliar o efeito de dois níveis (0,5% e 1%) de extrato hidro-alcoólico de marcela (Achyrocline satureioides) na segurança e qualidade de salames. No primeiro experimento, o microrganismo Lactobacillus plantarum foi fermentado em um meio de cultura de plasma suíno, com controle de pH, durante 36 horas, sob agitação contínua a 100 rpm e temperatura de 37 (± 0,1ºC). Após entrar na fase estacionária a cultura foi liofilizada e aplicada em salame, avaliando sua influência nas características microbiológicas, físico-químicas e sensoriais. Para efeitos comparativos, foram elaborados tratamentos sem adição de cultura starter e com adição de uma cultura comercial. No segundo experimento, salames foram elaborados com 0,5% e 1% de extrato hidro-alcoólico de marcela e sem extrato, considerados como controle. Os parâmetros de pH, atividade de água, cor e perda de peso foram avaliados durante a fabricação dos salames. Durante o armazenamento os valores de TBARS foram determinados e foi verificada a aceitação sensorial. O microrganismo Lactobacillus plantarum teve um crescimento máximo de 9,82 Log UFC.mL-1, após 30 horas de fermentação e apresentou 90,05% de sobrevivência a liofilização. Os salames elaborados com a cultura starter produzida apresentaram uma queda de pH significativamente mais rápida e uma menor atividade de água que os demais tratamentos. Além disso, o microrganismo Lactobacillus plantarum significativamente melhorou o sabor dos salames. A adição de extrato de marcela diminuiu (p<0,05) os valores de TBARS durante o armazenamento dos salames, comparado ao controle. O tratamento com 1% de extrato de marcela mostrou uma maior estabilidade lipídica do que aquele com 0,5%, porém apresentou uma diminuição (p<0,05) na aceitação sensorial. Os dois níveis de extrato de marcela não influenciaram significativamente os parâmetros de pH, atividade de água, cor e perda de peso. Portanto, este estudo indicou que o meio de cultura de plasma suíno é uma alternativa na produção comercial de bactérias ácido lácticas e que a cultura starter produzida proporcionou salames de maior segurança microbiológica e melhor aceitação sensorial. O extrato hidro-alcoólico de marcela diminuiu a oxidação lipídica e a concentração de 0,5% não alterou as características sensoriais, podendo, portanto, ser utilizada na elaboração de salames mais seguros aos consumidores.
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Avaliação de hidrolisados de caseína como antioxidantes em produtos cárneos e chocolate branco

Rossini, Karina January 2008 (has links)
Estudos recentes indicam que os peptídeos obtidos pela hidrolise enzimática da caseína podem apresentar atividades antioxidantes. Neste trabalho, previamente obteve-se os peptídeos através de hidrolise da caseína utilizando as enzimas Alcalase e Flavourzyme (4h, a 50ºC e pH 8), selecionando os que apresentaram as melhores características, in vitro, relativas à atividade antioxidante. A hidrolise enzimática utilizando a enzima Flavourzyme mostrou melhores resultados, com alto valor de proteína solúvel e conteúdo de aminoácidos livres, além de peptídeos de menor peso molecular do que com a Alcalase, como observado nas análises de cromatografia de permeação em gel e eletroforese em gel de poliacrilamida. Os peptídeos de caseína obtidos com a Flavourzyme também apresentaram melhores resultados utilizando o método ABTS na determinação da capacidade antioxidante. O hidrolisado obtido a partir da enzima Flavourzyme foi aplicado em produtos cárneos e em chocolate branco. Em produtos cárneos, os peptídeos de caseína (2.0%) inibiram, efetivamente, a peroxidação lipídica em carne moída (100%) e em carne mecanicamente separada de ave (CMS) (cerca de 20%) indicando que estes peptídeos podem ser utilizados nestes produtos, auxiliando na prevenção da formação de flavor desagradável e aumentando sua vida útil. Relativamente a sua aplicação em chocolate branco, esta adição teve o intuito de inibir escurecimento deste produto, fator considerado como limitante na sua vida-útil sendo conseqüência tanto de reações de escurecimento não enzimático quanto da oxidação de lipídeos. Os parâmetros que indicaram alteração lipidica e reações não enzimáticas foram mensurados em três diferentes amostras de chocolate branco: uma amostra com 0,2%, de manteiga de cacau, de antioxidante sintético Grindox 562, outra com 0,2%, de manteiga de cacau, dos peptídeos de caseína e a terceira amostra sem qualquer tipo de antioxidante. As amostras foram expostas a duas temperaturas diferentes: 20 ± 2 e 28 ± 2ºC. Os resultados das análises realizadas indicaram que as amostras armazenadas à temperatura de 20ºC apresentaram resultados significativamente melhores àqueles das amostras armazenadas à temperatura de 28ºC, relativos ao índice de acidez, à atividade de água, ao índice de peróxido, à cor e às substâncias reativas ao ácido tiobarbitúrico (TBARS), indicando melhor conservação deste produto. Também foi observado que a adição de quaisquer dos antioxidantes empregados não influenciou de forma significativa os resultados obtidos, evidenciandose assim, que o principal parâmetro responsável pelas alterações do chocolate branco em sua vida útil refere-se à temperatura de armazenamento a qual as amostras foram submetidas. / Recent studies indicate that peptides obtained by casein hydrolysis may have antioxidant activity. In this work, previous casein peptides were obtained by enzymatic hydrolysis using Alcalase and Flavourzyme (4h, at 50ºC and pH 8), selecting the ones that showed the best characteristics in vitro, related to the antioxidant activity. The enzymatic hydrolysis using Flavourzyme showed the best results, with higher soluble protein and free amino acid content and producing lower molecular weight peptides than Alcalase, as observed by gel permeation chromatography and polyacrylamide gel electrophoresis. Related to its application in meat products, casein peptides obtained with Flavourzyme also exhibited greater antioxidant capacity using the ABTS method. The casein hydrolyzed from Flavourzyme enzyme was applicated in ground beef homogenates, mechanically deboned meat (MDM) of poultry and white chocolate. In meat products, casein peptides (2.0%) effectively inhibited lipid peroxidation in ground beef homogenates (100%) and mechanically deboned meat (about 20%) of poultry. Casein peptides may be useful in meat processing as another naturally occurring antioxidant, helping to prevent off-flavor formation in meat products and increasing shelf life. In the use for white chocolate, the goal was to inhibit its browning, the main problems that limit the white chocolate’s shelf-life. Non-enzymatic browning reaction and lipid oxidation were involved directly in the browning of white chocolate. Thus, parameters which indicated fat alteration and non-enzymatic reactions were measured in three different samples of white chocolate. One sample with 0,2% of cocoa butter, with the synthetic antioxidant Grindox 562, other with 0,2% of cocoa butter, with the natural antioxidant and the third sample without any kind of antioxidant. The samples were exposed to two different temperatures: 20 ± 2 and 28 ± 2ºC. The results of the analysis made indicated that the samples stored at the temperature of 20ºC showed results significantly better to those samples stored at the temperature of 28ºC, related to the conservation of the white chocolate. Besides, the results indicated that the addition of any antioxidants employees has not influenced in a significant way the results obtained. Thus, it was evidenced that the main responsible parameter for the alterations of the white chocolate’s shelf-life is related to the storage temperature to which the samples were submitted.
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UTILIZAÇÃO DE VITAMINA E, SELÊNIO E CANTAXANTINA NA PRODUÇÃO E QUALIDADE DE OVOS DE POEDEIRAS COMERCIAIS / EFFECT VITAMIN E, SELENIUM AND CANTHAXANTHIN IN THE PRODUCTION AND QUALITY EGG OF LAYING HENS

Fernandes, Mariane de Oliveira 22 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The experiment was conducted in an experimental avian located at the Polytechnic School of the Federal University of Santa Maria. The aim of this study was to evaluate the antioxidant effect of vitamin E, Canthaxanthin and Organic Selenium on the quality of stored eggs (0, 7, 14, 21 and 28 days) and production rates of commercial layers from 40 to 55 week of age. In total, 320 hens females of lineage Novogen Brown were distributed in a completely randomized design with 5 treatments with 8 replicates of 8 hens each. The treatments were: T1 (DNC) - Diet Negative control; T2 (DCTX) - Diet with added 6ppm of Canthaxanthin; T3 (DVitE) - diet with 200 ppm of Vitamin E; T4 (DSe) - Diet with 0,4ppm Selenium; T5 (DCTXVitESe) - Diet with added 6ppm of Canthaxanthin + 200ppm of vitamin E + 0,4ppm of Selenium . The experimental phase was divided into four periods of 28 days. The laying rate was significantly affected in hens fed with DSe in the 3rd and 4th period. Hens from DSe and DCTXVitESe had higher egg weight in the 1st period and hens fed with DCTX had better egg weight in the 4th period. The DSe provided a better feed conversion per dozen eggs in the 4th period. The feed conversion by egg mass was better for hens fed DCTX, DSe and DCTXVitESe in the 4th period. Hens fed DCTX and DCTXVitESe had higher egg weight when stored for 28 days in the 1st period. Hens from DCTX had a better percentage yolk in eggs stored for 28 days in the 3rd period and, the 4th period for eggs without storage and in eggs with 14 days of storage. In the 4th period the hens fed with DVitE had a better percentage of yolk and albumen for eggs without storage and in the eggs with 21 days of storage. The albumen percentage was better in eggs with 28 days of storage and without storage from hens fed with DCTX in the 4th period. Hens fed DSe had a better yolk index in eggs stored for 28 days in the 1st period. Eggs of hens had a better yolk color with diets DCTX and DCTXVitESe in all periods. The use of the DSe was better for the variable Unit Haugh of eggs stored for 7 days in the 1st period. The lower content of substances which react with thiobarbituric acid (TBARS) was on egg yolks of the hens fed with DVitE in the 21 days of storage. There were no differences for the variables: feed consumption, body weight, vitelline membrane strength, percentage and thickness of shell, pH of albumen and specific gravity (P>0.05). The use of different additives contributes to improve of production rates and quality of eggs. / O experimento foi conduzido em um aviário experimental localizado no Colégio Politécnico da Universidade Federal de Santa Maria. O objetivo desse estudo foi avaliar o efeito antioxidante da Vitamina E, Cantaxantina e Selênio Orgânico sobre a qualidade de ovos armazenados (0, 7, 14, 21 e 28 dias) e índices produtivos de poedeiras comerciais da 40ª a 55ª semana de idade das aves. Foram utilizadas 320 fêmeas poedeiras da linhagem Novogen Brown distribuídas em um delineamento inteiramente casualizado em 5 tratamentos com 8 repetições de 8 aves cada. Os tratamentos consistiram em: DCN - Dieta Controle negativo; DCTX - Dieta com adição de 6ppm de Cantaxantina; DVitE - Dieta com 200ppm de Vitamina E; DSe - Dieta com 0,4ppm de Selênio; DCTXVitESe - Dieta com adição de 6ppm de Cantaxantina + 200ppm de Vitamina E + 0,4ppm de Selênio. A fase experimental foi dividida em 4 períodos de 28 dias. A taxa de postura foi afetada significativamente em aves que receberam a DSe no 3º e 4º período. As aves que receberam DSe e DCTXVitESe apresentaram maior peso de ovos no 1º período, no 4º período a DCTX obteve melhor peso de ovo. A DSe proporcionou uma melhor conversão alimentar por dúzias de ovos no 4º período. A conversão alimentar por massa de ovos foi melhor para aves alimentadas com DCTX, DSe e DCTXVitESe no 4º período. As aves alimentadas com DCTX e DCTXVitESe apresentaram maior peso de ovos quando armazenados por 28 dias no 1º período. As aves que receberam DCTX apresentaram um melhor percentual de gema em ovos armazenados durante 28 dias no 3º período, no 4º período para ovos sem armazenamento e em ovos com 14 dias de estocagem. No 4º período as aves alimentadas com DVitE apresentaram um melhor percentual de gema e de albúmen para ovos sem armazenamento e com 21 dias de estocagem. O percentual de albúmen foi melhor em ovos de aves alimentadas com DCTX no 4º período com 28 dias de armazenamento e sem armazenamento. Aves alimentadas com DSe apresentaram um melhor índice de gema em ovos armazenados por 28 dias no 1º período. Obteve-se uma melhor coloração de gema através da DCTX e DCTXVitESe em todos os períodos. A utilização da DSe foi melhor para a variável unidade Haugh em ovos armazenados por 7 dias no 1º período. O teor mais baixo de substâncias que reagem com o Ácido Tiobarbitúrico (TBARS), foi em gemas de ovos de poedeiras alimentadas com DVitE com 21 dias de armazenamento. Não foram encontradas diferenças estatísticas para as variáveis de consumo de ração, peso corporal, resistência da membrana vitelina, percentual e espessura de casca, pH de albúmen e densidade específica (P>0,05). A utilização dos diferentes aditivos contribui para a melhora dos índices produtivos e de qualidade de ovos.

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