Aboard the International Space Station, potable water will likely be produced from recycled wastewater. The National Aeronautic and Space Administration (NASA) plans to use iodine as a disinfectant, and, consequently, the formation of iodinated disinfection by-products (IDBPs) requires investigation. Objectives of this research were to determine possible precursors of IDBPs, identify IDBPs formed, and apply flavor profile analysis (FPA) as a tool to evaluate water qaulity. Experiments were performed by separately reacting iodine with each of the following organic compounds: methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, acetone, and formaldehyde. NASA previously identified all of these compounds in wastewater sources under consideration for recycling into potable water. Experiments were performed at pH 5.5 and 8, iodine concentrations of 10 and 50 mg/L, and organic concentrations of 5 and 50 mg/L. Gas chromatography/mass spectrometry was used to identify and monitor the concentrations of organic species. Spectrophotometry was used to monitor the iodine concentration. Acetone was the only compound identified as an IDBP precursor and it reacted to produce iodoacetone and iodoform. Concentrations of iodoform from 0.34 mg/L to 8.637 mg/L were produced at conditions that included each pH level, iodine concentration, and acetone concentration. The greatest iodoform concentration was produced at pH 8 from 50 mg/L of iodine and acetone. FPA indicated that the odor threshold concentration (OTC) of iodoform was 1.5 ug/L, and the OTC of iodine was 500 ug/L. Both iodine and iodoform have medicinal odors, making it difficult to distinguish each compound when present in a mixture. / Master of Science

Peanut skins have long been a waste product of the peanut industry. The aim of this project was to find suitable applications for this rich source of natural bioactive compounds. Solvent extracts of peanut skins and a multistep solvent extraction process to yield oligiomeric procyanidin (OPC) extracts were found to be inhibitory towards three types of yeasts (Saccharomyces cerevisiae, Zygosaccharomyces bailli, and Zygosaccharomyces bisporus). All extracts were devoid of solvents that may have interfered with the results. The OPC extract exhibited the highest inhibitory effect, and was chosen for fractionation. Fractionation was conducted by means of a silica or size exclusion high performance liquid chromatography (HPLC) column. Fractions were then subjected to a yeast growth curve assay to determine the active fractions. The fractions were then characterized by liquid chromatography-mass spectrometry (LC-MS). Negative mode electrospray MS determined the fractions to contain mostly procyanidins but also proanthocyanidins. Since it is possible for multiple compounds to display the same molecular ion, multistep MS and retention time differences were utilized to tentatively identify the compounds based upon their fragmentation schemes. However, co-elution was prominent, thus specific compounds responsible for yeast growth inhibition could not be determined. The yeast inhibition assay demonstrated that the procyanidin dimers up to tetramers had the best anti-yeast capabilities. / Ph. D.

This study evaluated the combination of ozone and granular activated carbon (GAC) treatment for the removal of sulfide and disinfection byproduct (DBP) precursors in drinking water at the pilot-scale. The research conducted was performed at the Auxiliary (Aux) and Main Water Treatment Plants (WTPs) in Sanford, Florida. Both WTPs rely upon groundwater sources that contain total sulfide ranging from 0.02 to 2.35 mg/L and total organic carbon (TOC) ranging from 0.61 to 2.20 mg/L. The Aux WTP’s raw water contains, on average, 88% more sulfide and 24% more TOC than the Main WTP. Haloacetic acids (HAA5) and total trihalomethanes (TTHMs) comprise the regulated forms of DBPs. HAA5 are consistently below the maximum contaminant level (MCL) of 60 μg/L, while TTHM ranges from 70 to 110 μg/L, at times exceeding the MCL of 80 μg/L in the distribution system. Ozone alone removed total sulfide and reduced UV-254 by about 60% at the Aux Plant and 35% at the Main Plant. Producing an ozone residual of 0.50 mg/L prevented the formation of bromate while removing approximately 35 to 60% concentration of DBP precursors as measured by UV-254. Operating the GAC unit at an empty bed contact time (EBCT) of 10 minutes for the Aux Plant and 5.5 minutes for the Main Plant resulted in 75% and 53% of UV-254 reduction, respectively. The average 120 hour TTHM formation potential for the Aux and Main Plants were 66 μg/L and 52 μg/L, respectively, after treatment by ozone and GAC. GAC exhaustion was deemed to have occurred after seven weeks for the Aux Plant and eleven weeks for the Main Plant. The GAC columns operated in three phases: an adsorption phase, a transitional phase, and a biologically activated carbon (BAC) phase. The GAC adsorption phase was found to produce the lowest TTHMs; however, TTHMs remained less than 80 μg/L during the BAC stage at each plant. BAC exhaustion did not occur iv during the course of this study. Ozone-GAC reduced chlorine demand by 73% for the Aux Plant and 10% for the Main Plant.

Master of Science / Department of Animal Sciences and Industry / Micheal J. Brouk / An evaluation of short-term replacement of corn silage (CS) and soybean meal with a blend of wet brewers grains (BG) and cracked corn on milk production and DMI was completed utilizing 8 primiparous (192 DIM) and 4 multiparous (191 DIM) mid-lactation Holstein cows. Milk production, composition, DMI, production efficiency, fatty acid composition and diet digestibility were evaluated. Cows were allotted to a 4 x 4 Latin Square with 3 replications blocked by parity, DIM and energy corrected milk (ECM). Crude protein and starch levels were balanced between diets by varying the levels of cracked corn and soybean meal in four diets; 0 BG (0% wet BG and 24% CS of diet DM), 12 BG (12% wet BG and 12% CS), 18 BG (18% wet BG and 6% CS), and 24 BG (24% wet BG and 0% CS). Fifteen day periods were used, d11-15 designated for collection. Orts were collected daily and TMRs were fed at 5 to 10% of previous day’s intake. Cows were milked 3x/day and individual milk weights recorded at every milking. Milk samples, body weights and BCS were taken -2 and -1d pre-trial to obtain baseline data and d14 and 15 of each period. During collection, samples of TMR and orts were taken d1, 3 and 5. Fecal grab samples were taken d12-15 at 8 hr intervals and advanced 2 hrs every 24 hr period to account for diurnal variation. Dry matter intake was similar (P=0.33) among treatments (20.3, 20.8, 20.9 and 21.2 kg/cow) for 0 BG, 12 BG, 18 BG AND 24 BG respectively, however CP intake of 24 BG tended to be greater (P=0.05) than 0 BG. NDF intake was lower for 0 BG compared to all other treatments and 24 BG was higher than 12 BG (P=0.0007). Dietary fat intake was different (P<0.001) across all treatments, increasing with greater BG inclusion. Inclusion of BG had no effect (P=0.37) on milk production (30.5, 31.5, 31.6 and 32.1 kg/cow), fat percent or amount, protein percent, SNF, lactose or SCC, but protein yield (P=0.04) was lower and MUN (P=0.05)tended to be lower with 0 BG compared to 18 BG and 24 BG. Efficiency of milk production did not differ (P=0.93) among treatments. Milk fatty acid profiles were different among treatments, with general increases of individual fatty acids as BG inclusion increased. No differences were found in DM, CP or ADF digestibility across treatments. Results suggest wet BG fed simultaneously with grass hay can be utilized as a short-term replacement for CS in mid-lactation dairy cow diets.

Master of Science / Department of Animal Sciences and Industry / Barry J. Bradford / Increased pressure for land use and greater demand for cereal grains have substantially increased feed costs for dairy producers. This has forced nutritionists to devise novel diet formulation strategies to help keep feed costs in check. As a result, dairymen are incorporating wet corn gluten feed (WCGF) into diets. Numerous studies have reported production responses to dietary inclusion of WCGF, but few have reported ruminal effects. Therefore an experiment was conducted to monitor production, while simultaneously measuring ruminal fermentation and total-tract digestion in 8 Holstein cows fed 0, 12, 24, and 36% WCGF (DM basis). Results from this study were consistent with recently published papers indicating that increasing dietary levels of WCGF linearly increases milk and milk component production. However, results demonstrate that this increase in production is related to an increase in feed intake, not improved digestibility. In addition to escalating grain prices, recent pressure for land and water use has led to a decrease in the availability of alfalfa. A second experiment was conducted to determine if forage fiber provided by alfalfa hay is necessary to maintain production in diets containing 31% WCGF (DM basis). Eighty primiparous and multiparous Holstein cows were utilized in two 4 × 4 Latin squares to evaluate the effects of feeding alfalfa at 0, 7, 14, and 21% of diet DM. Feeding higher proportions of alfalfa tended to increase ECM yield and decrease BW gain, suggesting that metabolizable energy supply was repartitioned from BW gain to milk production as more alfalfa was included. However, partial budget analysis determined that decreasing alfalfa inclusion rate may improve farm profitability by reducing feed costs and expenses associated with manure handling, despite small losses in productivity. Overall, these research projects suggest that large proportions of WCGF can effectively be fed to dairy cattle without sacrificing milk production, even without the use of alfalfa hay. Therefore, WCGF can be a cost-effective alternative to traditional dietary ingredients.

Estudos com a inclusão de glicerina bruta (GB) na alimentação animal vêm demonstrando benefícios quanto ao aporte energético conseguido, entretanto, existe uma variabilidade quanto aos teores de metanol encontrados na GB, nem sempre mensuradas, podendo apresentar riscos. Objetivou-se com este estudo: adaptar, otimizar e validar a metodologia oficial de determinação de metanol (MeOH) em biodiesel \"EN 14110\" para a matriz GB; aplicar o método para análise em amostras de glicerina bruta e avaliar o efeito do metanol na dieta de ruminantes por meio da técnica in vitro de produção de gases (PG). Foi utilizado um cromatógrafo gasoso Shimadzu modelo GC 2014 equipado com um detector de ionização de chamas (FID). Os parâmetros de validação foram linearidade, limite de detecção (LD) e quantificação (LQ), precisão, exatidão e efeito matriz. Foram analisadas duas amostras industriais de GB e uma obtida em laboratório por meio da reação de transesterificação do óleo de pinhão-manso (Jatropha curcas). A técnica semi automática de produção de gases foi utilizada para avaliar níveis crescentes de inclusão de MeOH na dieta via GB em substituição ao milho em grão a 0, 25, 50, 75 e 100%; correspondendo a doses de MeOH de 0, 0,018, 0,035, 0,053 e 0,071 mg, respectivamente. Como controle positivo foi adicionado um tratamento com inclusão de 8,3 mg MeOH puro na dieta controle sem inclusão de GB. As variáveis avaliadas foram produção de gases total (PGT), degradabilidade da matéria orgânica (DMO), eficiência na conversão de metano (CH4 effic) e o fator de partição (FP). As garrafas contendo as dietas foram incubadas a 39ºC por 24h. O método para análise de MeOH apresentou boa linearidade (r2 >= 0,99), e o LD e LQ foram 0,015 e 0,031%, respectivamente. Não foi observado efeito matriz significativo (4,36%). A precisão nas concentrações testadas, 0,05% e 0,5% foi de 2,09% e 2,39%, respectivamente. As concentrações de 0,05%, 0,2% e 0,5% (m/m) apresentaram recuperações de 88%, 95% e 91%, respectivamente. As amostras da indústria apresentaram teores de 0,047 e <LQ, enquanto que a obtida no laboratório apresentou 7,8% de metanol. A partir dos valores obtidos na produção de gases in vitro observou-se que a inclusão de GB contaminada com MeOH aumentou a DMO, PGT e CH4 e reduziu o FP. Conclui-se que o método é adequado para análise de MeOH em GB, com bom potencial para análise na matriz ração, quando otimizado. A GB contaminada com MeOH influencia a fermentação ruminal, sendo necessário mais estudos para elucidar os mecanismos envolvidos / Studies with the inclusion of crude glycerin (CG) in animal feed have demonstrated benefits on the energy intake achieved. However, there is a variation between the levels of methanol found in CG, not always analyzed, but often passed on to producers and may pose risks for using it as animal feed. The objective of this study was to optimize and to validate the official methodology \"EN 14110\" for determining methanol in biodiesel for CG matrix; to apply the method for analysis in commercial samples and samples produced in the laboratory; and to evaluate the effect of methanol in ruminant feed through the in vitro gas production technique (PG). It was used a Shimadzu gas chromatograph model 2014 GC equipped with a flame ionization detector (FID). The validation parameters were linearity, limit of detection (LOD) and quantification (LOQ), precision, accuracy and matrix effect. There were analyzed two industrial\'s samples and a sample obtained in the laboratory by transesterification of the oil from Jatropha curcas. The semi-automatic in vitro gas production technique was used to evaluate the use of MeOH inclusion in the ruminant diet via CG replacing corn grain at 0, 25, 50, 75 and 100%, corresponding to MeOH doses of 0, 0.018, 0.035, 0.053 and 0.071 mg respectively. As a positive control treatment was added with the inclusion of 8.3 mg pure MeOH. The variables evaluated were total gas production (GP), degradability of organic matter (DMO), efficiency in methane conversion (CH4 effic) and the partition factor (PF). The bottles containing the diets were incubated at 39 ° C for 24h. The method showed good linearity (r2 >= 0.99), the LOD and LOQ were 0.015 and 0.031%, respectively. There was no significant matrix effect (4.36%). The accuracy of the concentration tested, 0.05% e 0.5% was 2.09% and 2.39%, respectively. The concentrations 0.05%, 0,2% and 0.5% (w/w) showed recovery level of 88%, 95% e 91% respectively. The industry samples concentrations were 0.047 and <LOQ, while the laboratory one showed 7.8% of methanol. The in vitro gas production showed that the addition of CG increased GP, DMO and CH4 effc and reduced PF. It was concluded that the method is suitable for analysis in CG MeOH, with good potential for analysis of the feed array after optimization. CG contaminated with MeOH influence ruminal fermentation, requiring further studies to elucidate the mechanisms involved

Os efeitos do fornecimento de dietas contendo glicerina bruta foram avaliados em quatro experimentos com ovinos de diferentes categorias. Experimento 1: Quarenta cordeiros foram usados para avaliar os efeitos da inclusão de glicerina bruta sobre o desempenho, as características de carcaça e da carne e a concentração de enzimas hepáticas. As rações experimentais foram isonitrogenadas, sendo que o ajuste proteico foi realizado pela inclusão de ureia e farelo de soja. Os teores de inclusão de glicerina bruta foram: 0, 5, 10 ou 15% na MS. A adição de glicerina bruta causou efeito quadrático no CMS, CFDN, CPB, GMD e peso final. A inclusão de glicerina causou efeito quadrático para peso corporal ao abate, PCQ e PCF. Foi observado efeito quadrático para os ácidos graxos mirístico, palmítico, palmitoleico, linoleico e rumênico. A glicerina bruta demonstrou ser um bom substituto do milho em dietas com alto teor de concentrado, melhorando o desempenho e as características da carcaça dos animais quando incluída até 10% na MS. Experimento 2: Cinquenta cordeiros(as) foram usados para avaliar os efeitos da inclusão de glicerina bruta em rações com alta proporção de concentrado, sobre o desempenho, características de carcaça e parâmetros enzimáticos. As rações experimentais foram isonitrogenadas, sendo o ajuste proteico realizado pela inclusão de farelo de soja. Os teores de inclusão de glicerina bruta foram: 0, 5, 10, 15 e 20% na MS. A inclusão de glicerina bruta não afetou as variáveis de desempenho analisadas. Houve apenas efeito linear para o CMM. A glicerina bruta pode substituir o milho em até 20%, mantendo o desempenho dos animais e as características de carcaça. Experimento 3: Cinco borregos canulados no rúmen foram utilizados para avaliar os efeitos da glicerina bruta sobre os parâmetros ruminais, a digestibilidade das dietas e o metabolismo de nitrogênio. As dietas foram isonitrogenadas e os teores de inclusão de glicerina bruta foram: 0, 5, 10, 15 ou 20% na MS. Houve redução linear na ingestão de FDN e aumento linear na ingestão de MM. Houve efeito linear crescente para a digestibilidade da MS e MO. A inclusão de glicerina bruta causou redução linear no acetato, relação C2:C3, AGCC total, e aumento linear no pH ruminal. A glicerina bruta pode substituir até 20% do milho em dietas de borregos, melhorando a digestibilidade da MS e MO. Experimento 4: Cento e dezoito ovelhas com 90 dias de prenhez foram utilizadas para avaliar a inclusão de glicerina bruta em dietas de gestação e lactação. Os teores de inclusão foram 0 ou 10%. Da segunda a oitava semana foi mensurado o CMS e produção de leite das ovelhas e a ingestão de concentrado inicial dos cordeiros. A inclusão de glicerina bruta aumentou o CMM e reduziu a porcentagem de gordura no leite. A adição da glicerina bruta na dieta das ovelhas diminuiu a concentração sérica de AGNE. A inclusão de 10% de glicerina bruta na dieta de ovelhas durante a gestação e lactação não prejudica o desempenho dos animais e reduz a possibilidade de ocorrência de toxemia da gestação. / The effects of feeding diets with crude glycerin were evaluated in 4 trials using different categories of sheep. Experiment 1: Forty Santa Inês ram lambs were used to determine the effects of partial replacement of corn by crude glycerin on growth, hepatic enzymes, carcass and meat characteristics of lambs fed high-concentrate diets. The diets were isonitrogenous and the protein was adjusted by increasing urea and soybean meal. Increasing levels of crude glycerin were: 0, 5, 10 or 15%. There was quadratic effect for DMI, NDFI, CPI. ADG and final weight. There was a quadratic effect for slaughter BW and dressing percentage, but no difference on longissimus muscle area, backfat thickness and body wall thickness. There was quadratic effect for myristic, palmitic, palmitoleic, linoleic and rumenic acid. Crude glycerin is a good substitute of corn in high-concentrate diets, improving performance and carcass characteristics when included until 10% of the diet DM. Experiment 2: Fifty lambs were used to determine the effects of partial replacement of corn by crude glycerin on growth, carcass characteristics and hepatic enzymes of lambs fed high concentrate diets. The diets were isonitrogenous and the protein adjusted was performed with increased soybean meal. Increasing levels of crude glycerin were: 0, 5, 10, 15 or 20%. There was an increased in mineral matter intake. Crude glycerin can be used as a substitute for corn in high concentrate diets of ram lambs without affecting performance and carcass characteristics. Experiment 3: Five Santa Inês ram lambs, cannulated in the rumen, were used to determine the effects of using crude glycerin on ruminal constituents, diet digestibility and nitrogen metabolism. The diets were isonitrogenous and crude glycerin was included in the ration at 0%, 5%, 10%, 15% or 20% in the DM. There was linear decreased on NDF intake and a linear increase in ash intake. Feeding crude glycerin increased DM and OM digestibility. Crude glycerin decreased acetate, acetate:propionate ratio, total SCFA and showed a linear increase on pH. Replacing corn by crude glycerin up to 20% of dietary DM increased DM and OM digestibility, maintained propionate and decreased acetate and total SCFA. When soybean meal was used to adjust the diet protein level, there were no changes on nitrogen metabolism. Experiment 4: One hundred and eighteen 90 d pregnant ewes were used to determine the effects of feeding crude glycerin on performance, NEFA concentration and lamb growth. Diets were isonitrogenous and crude glycerin levels were zero or 10%. From the second until de eighth week of lactation DM intake of the ewes and starter of the lambs were measured. There was an increase on ash intake for the glycerin fed ewes. There was a decrease in milk fat percentage. Crude glycerin fed ewes showed a decrease on blood NEFA. The inclusion of 10% of crude glycerin in the diets of sheep during pregnancy and lactation had no detrimental effect on performance of ewes and lambs. Using 10% of crude glycerin decreases the chances of pregnancy toxemia in ewes.

O objetivo do presente estudo foi verificação da viabilidade da aplicação de gelatina de pés de frango em spread de chocolate como substituto parcial de gordura. Inicialmente apresentou-se uma revisão de literatura sobre os principais aspectos que envolvem a pesquisa. Após relatou-se a metodologia de extração e caracterização físico-química da gelatina obtida de pés de frango por meio de análises de composição centesimal, de cor, força de gel e análise de perfil de textura (TPA). Posteriormente abordou-se os efeitos da aplicação de gelatina como substituto de gordura nas propriedades físico-químicas e reológicas de spread de chocolate. Por último investigou-se a influência da concentração de gelatina e substituição de gordura na espalhabilidade, estabilidade (shelf life), custos e propriedades sensoriais dos spreads de chocolate. Para tanto, foi utilizado planejamento experimental Central Composto Rotacional e metodologia de superfície de resposta. Os resultados da extração de gelatina de subproduto de frango indicaram que as peles e tendões dos pés de frango possuem rendimento (7,83 %) e conteúdo mineral (1,92 %), apresentando alto teor proteico (84,96 %) próximo das gelatinas comerciais. Em concentração de 6,67 % a gelatina demonstrou elevada força de gel (294,78 g), comportando-se na análise de perfil de textura como um sólido. Os dados relacionados às formulações de spread de chocolate demonstraram que tanto o nível de substituição de gordura quanto a concentração de gelatina exerceram efeitos significativos (p<0,05) sobre a cor, volume, densidade e comportamento reológico dos produtos, exceto a atividade de água que foi influenciada apenas pelo primeiro fator. Sob a perspectiva reológica apenas a amostra com maior nível de substituição de gordura foi classificada como pseudoplástica. A gelatina contribuiu no aumento do teor proteico das formulações. A consistência foi significativamente (p<0,05) influenciada pelas propriedades da fase de gelatina, apresentando ampla faixa de plasticidade nas diferentes temperaturas (10, 20 e 30 °C). A consistência dos spreads aumentou em todas as temperaturas durante os 90 dias de armazenamento. Observou-se por meio da análise sensorial que os fatores em estudo provocaram alterações nos atributos sensoriais do produto suficiente para a percepção dos provadores. A formulação com 75 % de substituição de gordura seguida pelas formulações com 50 % e 0,8 % de concentração de gelatina apresentaram a maior aceitabilidade. Com o máximo de substituição de gordura chegou-se a 53 % de redução de custos. Contudo, os resultados obtidos sugerem que a aplicação de gelatina de pés de frango pode ser vantajosa, já que contribuiu com a formulação de spreads de chocolate menos calóricos e com propriedades físico-químicas e sensoriais adequadas para uma possível comercialização. / The aimed of this study was the verification of the feasibility of application of gelatin chicken feet in chocolate spread as a partial replacement fat. Firstly, it was presented a literature review on the main aspects involved in the research. After it was reported the extraction methodology and physicochemical characterization of chicken feet gelatin through chemical composition, color, gel strength and texture profile analysis (TPA) analysis. Next, the effects of the gelatin application as a fat replacement in physicochemical and rheological properties of chocolate spread were discussed. Finally, the influence of the gelatin concentration and fat replacement in spreadability, stability (shelf life), costs and sensory properties of chocolate spread were investigated. For this purpose, the Central Composite Rotational Design and response surface methodology were used. The results of the chicken feet gelatin extraction indicated that the skins and tendons of chicken feet have yield (7.83%) and mineral content (1.92%), with high protein content (84.96%) close to the commercial gelatins. In concentration of 6.67 % gelatin demonstrated high gel strength (294.78 g), behaving in the texture profile analysis as a solid. Data related to the spread chocolate formulations demonstrated that the level of replacement of fat and gelatin concentration exerted a significant effect (p <0.05) on the color, volume, density and rheological behavior of the products, except water activity which was influenced only by the first factor. Under the theological perspective only the sample with higher levels of fat replacement was classified as shear thinning. Gelatin contributed in increasing the protein content of the formulations. The consistency was significantly (p <0.05) influenced by the properties of the gelatin phase, showing a wide range of plasticity at different temperatures (10, 20 and 30 ° C). The spreads consistency increased at all temperatures during the 90 days of storage. It was observed by means of sensory analysis that the factors under study led to changes in the sensory attributes of the product enough to the perception of tasters. The formulation with 75 % fat replacement followed by 50 % and 0.8 % concentration of gelatin had the highest acceptability. With maximum fat replacement was reached to 53% cost reduction. However, the results suggest that the application of chicken feet gelatin can be advantageous since it contributed to the formulation of lower calorie chocolate spreads, with physicochemical and sensory properties suitable for possible commercialization.

O objetivo do presente estudo foi verificação da viabilidade da aplicação de gelatina de pés de frango em spread de chocolate como substituto parcial de gordura. Inicialmente apresentou-se uma revisão de literatura sobre os principais aspectos que envolvem a pesquisa. Após relatou-se a metodologia de extração e caracterização físico-química da gelatina obtida de pés de frango por meio de análises de composição centesimal, de cor, força de gel e análise de perfil de textura (TPA). Posteriormente abordou-se os efeitos da aplicação de gelatina como substituto de gordura nas propriedades físico-químicas e reológicas de spread de chocolate. Por último investigou-se a influência da concentração de gelatina e substituição de gordura na espalhabilidade, estabilidade (shelf life), custos e propriedades sensoriais dos spreads de chocolate. Para tanto, foi utilizado planejamento experimental Central Composto Rotacional e metodologia de superfície de resposta. Os resultados da extração de gelatina de subproduto de frango indicaram que as peles e tendões dos pés de frango possuem rendimento (7,83 %) e conteúdo mineral (1,92 %), apresentando alto teor proteico (84,96 %) próximo das gelatinas comerciais. Em concentração de 6,67 % a gelatina demonstrou elevada força de gel (294,78 g), comportando-se na análise de perfil de textura como um sólido. Os dados relacionados às formulações de spread de chocolate demonstraram que tanto o nível de substituição de gordura quanto a concentração de gelatina exerceram efeitos significativos (p<0,05) sobre a cor, volume, densidade e comportamento reológico dos produtos, exceto a atividade de água que foi influenciada apenas pelo primeiro fator. Sob a perspectiva reológica apenas a amostra com maior nível de substituição de gordura foi classificada como pseudoplástica. A gelatina contribuiu no aumento do teor proteico das formulações. A consistência foi significativamente (p<0,05) influenciada pelas propriedades da fase de gelatina, apresentando ampla faixa de plasticidade nas diferentes temperaturas (10, 20 e 30 °C). A consistência dos spreads aumentou em todas as temperaturas durante os 90 dias de armazenamento. Observou-se por meio da análise sensorial que os fatores em estudo provocaram alterações nos atributos sensoriais do produto suficiente para a percepção dos provadores. A formulação com 75 % de substituição de gordura seguida pelas formulações com 50 % e 0,8 % de concentração de gelatina apresentaram a maior aceitabilidade. Com o máximo de substituição de gordura chegou-se a 53 % de redução de custos. Contudo, os resultados obtidos sugerem que a aplicação de gelatina de pés de frango pode ser vantajosa, já que contribuiu com a formulação de spreads de chocolate menos calóricos e com propriedades físico-químicas e sensoriais adequadas para uma possível comercialização. / The aimed of this study was the verification of the feasibility of application of gelatin chicken feet in chocolate spread as a partial replacement fat. Firstly, it was presented a literature review on the main aspects involved in the research. After it was reported the extraction methodology and physicochemical characterization of chicken feet gelatin through chemical composition, color, gel strength and texture profile analysis (TPA) analysis. Next, the effects of the gelatin application as a fat replacement in physicochemical and rheological properties of chocolate spread were discussed. Finally, the influence of the gelatin concentration and fat replacement in spreadability, stability (shelf life), costs and sensory properties of chocolate spread were investigated. For this purpose, the Central Composite Rotational Design and response surface methodology were used. The results of the chicken feet gelatin extraction indicated that the skins and tendons of chicken feet have yield (7.83%) and mineral content (1.92%), with high protein content (84.96%) close to the commercial gelatins. In concentration of 6.67 % gelatin demonstrated high gel strength (294.78 g), behaving in the texture profile analysis as a solid. Data related to the spread chocolate formulations demonstrated that the level of replacement of fat and gelatin concentration exerted a significant effect (p <0.05) on the color, volume, density and rheological behavior of the products, except water activity which was influenced only by the first factor. Under the theological perspective only the sample with higher levels of fat replacement was classified as shear thinning. Gelatin contributed in increasing the protein content of the formulations. The consistency was significantly (p <0.05) influenced by the properties of the gelatin phase, showing a wide range of plasticity at different temperatures (10, 20 and 30 ° C). The spreads consistency increased at all temperatures during the 90 days of storage. It was observed by means of sensory analysis that the factors under study led to changes in the sensory attributes of the product enough to the perception of tasters. The formulation with 75 % fat replacement followed by 50 % and 0.8 % concentration of gelatin had the highest acceptability. With maximum fat replacement was reached to 53% cost reduction. However, the results suggest that the application of chicken feet gelatin can be advantageous since it contributed to the formulation of lower calorie chocolate spreads, with physicochemical and sensory properties suitable for possible commercialization.

Made available in DSpace on 2015-04-22T22:08:50Z (GMT). No. of bitstreams: 1 DISSERTACAO_OTAVIO AUGUSTO PAIVA.pdf: 8701931 bytes, checksum: fa7ddfc8f71e05d7fe06a55c98faefc8 (MD5) Previous issue date: 2009-08-07 / Fundação de Amparo à Pesquisa do Estado do Amazonas / The experimental program of the present project was developed in order to evaluate the residue performance of ground plain glasses in cement based paste and mortar. Different conditions of grounding were used to generate a material with particles of the same order of magnitude of the cement particles. The ground glass residue (GGR) displayed physicalchemistry characteristics compatible to the ones of pozzolan, with relevance to the pozzolanic activity index (PAI). PAI equal to 104% was obtained, which is higher than that 75% -minimum value required by the Brazilian standard. The GGR was used in paste and mortar as a partial replacement of cement of 0%, 10%, 15% and 20% in mass, considering a waterbinder ratio of 0,4. The GGR behavior was evaluated through the X-Ray diffraction, thermal analysis, compressive strength, modulus of elasticity, porosity, water absorption, and alkaliaggregate reaction. The results did not indicate difference between the mechanical strength of the pastes with GGR and reference mixture after 28 days of curing. In mortars, the results of mechanical strength of the GGR mixtures were adequate from 7 days due to the filler and pozzolanic effects, mainly the 20% GGR mortar. In particular, the GGR provided increasing of compressive strength of 14% and 22% after 28 and 56 days of curing, respectively. / O programa experimental realizado no presente projeto foi desenvolvido de forma a avaliar o desempenho do resíduo de vidros planos moídos em pastas e argamassas a base de cimento Portland. Foram estudadas diferentes condições de moagem que possibilitassem a obtenção de um material com partículas da mesma ordem de gRandeza das partículas do cimento. O resíduo de vidro moído (RVM) apresentou características físico-químicas compatíveis às da pozolana, com destaque para o índice de atividade pozolânica. Obteve-se valor de 104%, empregando o cimento, que é superior a 75%, prescrito na norma brasileira. O RVM foi aplicado em pastas e argamassas como substituto parcial do cimento, para teores de 0%, 10%, 15%, e 20% em massa, para uma relação água-aglomerante de 0,4. O comportamento do RVM foi avaliado através de ensaios de difração de raios X, análise térmica, resistência à compressão, porosimetria, absorção, permeabilidade, módulo de elasticidade e reação álcaliagregado. Os resultados indicaram que as resistências mecânicas das pastas com RVM alcançaram o valor da resistência de referência a partir dos 28 dias. Nas argamassas foram obtidos resultados satisfatórios de resistência mecânica a partir dos 7 dias, iniciado pelo efeito de preenchimento e, posteriormente, pelo efeito pozolânico que superou os resultados de referência após os 28 dias, principalmente para o teor de 20%. Particularmente, o RVM aumentou a resistência à compressão em 14 e 22% após os 28 e 56 dias de cura, respectivamente.