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Caracter?sticas do leite cru e do queijo minas artesanal produzidos na regi?o do Serro, Minas Gerais e, produ??o de queijos com doces / Characteristics of raw milk and artisanal Minas cheese produced in the region of Serro, Minas Gerais and production of cheeses with sweetFigueiredo, Silvania Pereira de 11 March 2014 (has links)
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Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Esta pesquisa foi conduzida com o objetivo de se avaliar o leite cru e o queijo Minas artesanal do Serro, Minas Gerais, rec?m-fabricado e maturado e, a produ??o de queijo com doces. Amostras foram coletadas em cinco propriedades rurais, aleatoriamente selecionadas de um total de 32 certificadas pelo Instituto Mineiro de Agropecu?ria. O leite e o queijo rec?m-fabricados foram coletados a cada dois meses, durante 6 meses. Para a pesquisa de altera??es decorrentes da matura??o, foram coletados 25 queijos com 3 dias de fabrica??o no m?s de janeiro (ver?o chuvoso) e 25 no m?s de julho (inverno seco). Os queijos foram maturados em c?mara fria (8 ?C/Umidade Relativa de 85 %) por 15, 30, 45 e 60 dias, sendo realizadas, tamb?m, an?lises no tempo inicial. Para o leite cru procedeu-se ? determina??o da acidez titul?vel, densidade, teores de gordura, prote?na, lactose, umidade, massa seca total, res?duo mineral fixo, quantifica??o de coliformes totais e coliformes termotolerantes, contagem total de bact?rias l?ticas, de micro-organismos aer?bios mes?filos, de Staphylococcus spp. e Staphylococcus coagulase positiva. Para o queijo rec?m-fabricado foram realizadas as an?lises de pH, atividade de ?gua mais as mencionadas para o leite, com exce??o da densidade e teor de lactose e com a inclus?o das an?lises instrumentais de firmeza, adesividade e cor (L* a* b*, croma e matiz). O teor de gordura do queijo foi corrigido para mat?ria seca. Para a pesquisa de matura??o foram realizadas as an?lises mencionadas para o queijo rec?m-fabricado, exceto atividade de ?gua e, incluindo-se contagem de fungos filamentosos e leveduras. Para os queijos com doces, o controle consistiu de queijo produzido sem doce. Os doces em ponto de corte foram fracionados em cubos de 2 cm2 e adicionados ? regi?o central do queijo durante a enformagem. Mensurou-se a firmeza na superf?cie e na regi?o central dos queijos, luminosidade (L*), intensidade de vermelho-verde (a*), intensidade de amarelo (b*), croma (C), matiz (H?), pH, umidade, massa seca, gordura, gordura corrigida para a massa seca, prote?na, carboidrato total, res?duo mineral fixo e energia metaboliz?vel total. As an?lises foram conduzidas no queijo rec?m-fabricado e nos tempos de 15, 30, 45 e 60 dias de armazenamento. Houve varia??o (p<0,05) na acidez, lactose, contagens de coliformes termotolerantes e bact?rias l?ticas no leite cru. Dentre estas, ressalta-se a maior acidez e menor teor de lactose em janeiro, mar?o, julho, setembro e novembro, meses que tamb?m apresentaram maiores contagens de coliformes termotolerantes e bact?rias l?ticas. Nos queijos houve varia??o (p<0,05), ao longo dos meses, para pH, acidez, gordura corrigida para a massa seca, massa seca, firmeza, adesividade, intensidade de verde (?a*), intensidade de amarelo (b*), croma (C), atividade de ?gua, contagens de coliformes termotolerantes e Staphylococcus spp. Quanto ao estudo da matura??o, no ver?o a umidade dos queijos diminuiu linearmente com o aumento do tempo de matura??o, enquanto que no inverno, os valores de umidade diminu?ram at? os 30 dias de matura??o seguido por aumento a partir dos 45 dias. As contagens de coliformes termotolerantes e Staphylococcus coagulase positiva mantiveram-se altas no ver?o, as quais, no entanto, reduzidas durante o tempo de matura??o. A popula??o de fungos aumentou na medida em que se aumentou o tempo de matura??o, havendo maior crescimento no per?odo de ver?o. Observou-se que no ver?o os queijos apresentaram textura mais firme. Nos queijos produzidos com doces, observou-se que a firmeza na superf?cie e no centro foram maiores ao longo do per?odo de armazenamento. A firmeza na superf?cie foi semelhante entre o queijo controle e os queijos com goiabada e bananada. A firmeza no centro, no entanto, foi menor nos queijos com doce. Os par?metros de cor (L*a*b* C H?) do queijo controle, do queijo com goiabada e do queijo com bananada n?o apresentaram varia??o significativa ao longo do per?odo de armazenamento. A luminosidade (L*) dos queijos com goiabada e bananada foi superior a do controle. O queijo com bananada apresentou luminosidade (L*), intensidade de amarelo (b*), matiz (H?) e croma (C) maior que o queijo controle. Os queijos produzidos com goiabada e bananada apresentaram o teor de res?duo mineral fixo semelhante ao queijo controle. Entretanto, apresentaram menor pH, maior umidade, menor teor de massa seca, menor teor de gordura, menor teor de gordura corrigida para massa seca, menor teor de prote?na, maior teor de carboidrato total e menor energia metaboliz?vel quanto comparados ao controle. H? necessidade de melhorias da qualidade higi?nico-sanit?ria na obten??o do leite e na produ??o do queijo, a fim de reduzir contamina??es microbianas e melhorar a efici?ncia da matura??o. Quanto aos queijos produzidos com doces, h? potencial de se produzir queijos com goiabada e bananada tanto em ?mbito industrial quanto artesanal. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT
This research was conducted with the objective of evaluating the raw milk and artisan cheese Minas Serro, Minas Gerais, newly manufactured and matured, and the production of cheese with candy. Samples were collected from five farms were randomly selected from a total of 32 certified by the Instituto Mineiro de Agropecu?ria. The milk and freshly made ??cheese were collected every two months for six months. To search for changes resulting from maturation, 25 cheeses with three days of manufacturing were collected in January (rainy summer) and 25 in July (dry winter). The cheeses were matured in a cold room (8 ?C/85 % Relative Humidity) for 15, 30, 45 and 60 days, and also conducted analyzes at the initial time. For raw milk proceeded to the determination of titratable acidity, density, levels of fat, protein, lactose, moisture, total dry matter, fixed mineral, quantification of total coliforms and fecal coliforms, total count of lactic acid bacteria, micro-mesophilic aerobic organisms, Staphylococcus spp. and Staphylococcus coagulase positive. For newly manufactured cheese analyzes of pH, water activity, plus listed for milk, with the exception of density and lactose content and the inclusion of instrumental analyzes of firmness, stickiness and color (L* a* b* were performed, chroma and hue). The fat content of the cheese was corrected for dry matter. To search maturation analyzes mentioned for the newly manufactured cheese except water activity were made and, including counts of filamentous fungi and yeasts. For cheeses with sweet, control consisted of cheese produced without the sweet. Candy in cutoff were fractionated into cubes of 2 cm2 and added to the central region of the cheese during enformagem. Firmness is measured at the surface and in the central region of the cheeses, lightness (L*), redness-green (a*), yellow intensity (b*), chroma (C), hue (H ?), pH , moisture, dry matter, fat, fat corrected for dry matter, protein, total carbohydrate fraction, fixed mineral and metabolizable energy total. Analyses were conducted on newly manufactured cheese and times of 15, 30, 45 and 60 days of storage. There was variation (P<0.05) in acidity, lactose, counts of fecal coliform and lactic acid bacteria in raw milk. Among these, it is the higher acidity and lower content of lactose in January, March, July, September and November, months that also showed high counts of fecal coliform and lactic acid bacteria. In cheeses was no change (P<0.05), over the months, for pH, acidity, fat corrected for dry weight, dry weight, firmness, adhesiveness, intensity of green (-a*), yellow intensity (b*), chroma (C), water activity, counts of thermotolerant coliforms and Staphylococcus spp. Regarding the study of maturation in the summer moisture cheeses decreased linearly with increasing aging time, whereas in winter, the moisture values ??decreased until 30 days of ripening followed by an increase after 45 days. Coliform counts and coagulase positive Staphylococcus remained high in the summer, which, however, decreased during maturation time. The population of fungi increased in that time increased maturation, with higher growth in the summer. It was observed that in summer the cheeses had firmer texture. In cheeses made with sweet, it was observed that the strength at the surface and in the center were higher throughout the storage period. The firmness on the surface was similar between the control cheese and cheese with guava and bananada. The firmness in the center, however, was lower in cheeses with sweet. The color parameters (L* a* b* C H?) of the control cheese, cheese with guava and cheese with bananada showed no significant variation throughout the storage period. The lightness (L*) of cheeses with guava and bananada was higher than the control. The cheese bananada presented with lightness (L*), yellow intensity (b*), hue (H?) and chroma (C) greater than the control cheese. Cheeses made with guava and bananada presented the fixed mineral content similar to the control cheese. However, had lower pH, higher humidity, lower dry matter content, lower fat, lower fat corrected to dry mass, lower protein, higher total carbohydrate and lower metabolizable energy as compared to the control. There is a need for improvement of the sanitary quality of the milk for obtaining and producing cheese, in order to reduce microbial contamination and improve the efficiency of maturation. As for cheeses made with sweet, there is potential to produce cheeses with guava and bananada both industrial as artisanal level.
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Avalia??o do potencial da torta de buriti (Mauritia flexuosa L.) para obten??o de bioetanol de segunda gera??oGomes, Pedro Henrique de Oliveira 19 August 2016 (has links)
Disponibiliza??o do conte?do parcial, conforme Termo de Autoriza??o. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-02-06T17:43:23Z
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Previous issue date: 2016 / O bioetanol pode ser produzido a partir de materiais lignocelul?sicos, que s?o constitu?dos de
carboidratos complexos na forma de celulose, hemicelulose e amido, ampliando as
possibilidades de fontes de energias alternativas. Uma dessas s?o os res?duos agr?colas, como
as tortas, coprodutos de processos de extra??o mec?nica de ?leos de frutos, sementes e cereais
(oleaginosas), que representam um desafio por muitas vezes n?o possu?rem um destino vi?vel
ou at? rent?vel que atenda as exig?ncias ambientais. Um desses ? o buriti (Mauritia flexuosa
L.), fonte de um ?leo com alto teor de caroten?ides representando, assim, aplica??es em
ind?strias aliment?cias, cosm?ticas e farmacol?gicas e resultando em ac?mulo de seu material.
O trabalho foi desenvolvido a partir da torta de buriti obtida ap?s extra??o mec?nica de seu
?leo. Foi verificado que a torta ? constitu?da por aproximadamente 44% de sua massa por
carboidratos livres ou polimerizados. Foram realizados tratamentos qu?micos com solu??es de
?cido dilu?do e base em duas etapas distintas, a fim de promover a remo??o da hemicelulose e
lignina. Por fim, foi feita a hidr?lise com complexo enzim?tico de celulases, enzimas que
hidrolisam cadeias celul?sicas em monossacar?deos de glicose, substrato utilizado por
microrganismos como a levedura Saccharomyces cerevisiae no metabolismo celular, tendo
como produto excretado o etanol. Ap?s a hidr?lise enzim?tica, obteve teores de 53,58%
(m/m) de glicose liberada do farelo tratado, apresentando um rendimento em torno de 60%
(m/m). Com a fermenta??o do hidrolisado, obtido ap?s o tratamento enzim?tico, foi verificada
a obten??o de etanol em rendimento (fator de convers?o de substrato em produto, Yp/s) de
0,43 em rela??o ? quantidade de substrato utiliza??o na hidr?lise enzim?tica. O produto obtido
foi analisado em cromat?grafo a g?s acoplado ao espectr?metro de massa, confirmando a
obten??o de bioetanol. Al?m disso, foram realizadas medidas de microscopia eletr?nica por
varredura e difratometria de raios-X, verificando altera??es na estrutura f?sica e morfol?gica
do material ao longo do processo. Por fim, ratificou-se a possibilidade de aplicar a torta de
buriti na obten??o de etanol de segunda gera??o. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Bioethanol can be produced from lignocellulosic materials, that are made up of carbohydrate
complexes in the form of cellulose, hemicellulose and starch, expanding the possibilities of
alternative energy sources. One of these are agriculture residues, such as pies, co-products of
mechanical extraction processes of fruit oils, seeds and cereals (oil), which represent a
challenge in many times do not possess a viable or even profitable destination that meets the
environmental requirements. One of these is the buriti (Mauritia flexuosa L.), source of a oil
with high content of carotenes, representing thus, applications in food industries, cosmetic
and pharmaceutical, resulting in accumulation of its material. The work was developed from
the buriti pie obtained after mechanical extraction of its oil. It was verified that the pie is
comprise by approximately 44% of its mass by free carbohydrates or polymerized. Chemical
treatments were performed with dilute acid solutions and base in two distinct steps in order to
promote the removal of hemicellulose and lignin. Finally, the hydrolysis was done with the
enzyme complex of cellulases, enzymes that hydrolyze cellulose chains in monosaccharide
glucose, a substrate used by microorganisms such as Saccharomyces cerevisiae yeast in cell
metabolism, with ethanol as the product excreted . After enzymatic hydrolysis, it was
obtained content of 53.58% (m/m) of glucose released from the treated bran, showing a yield
around 60% (m/m). With the fermentation of the hydrolyzate obtained after the enzymatic
treatment was verified obtaining of ethanol in yield (substrate conversion factor in product,
Yp / s) of 0.43 compared to the amount of substrate used in the enzymatic hydrolysis. The
obtained product was analyzed in a gas chromatograph coupled to a mass spectrometer,
confirming obtaining bioethanol. In addition, were carried out measures of scanning electron
microscopy and X-ray diffraction, checking changes in physical and morphological structure
of the material throughout the process. Finally, ratifies the possibility of applying the buriti
pie in getting second-generation ethanol.
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Aprimoramento do processo de gera??o de oz?nio conduzido a partir da eletr?lise da ?gua pura / Improvement of the ozone generation process carried out from the electrolysis of the electrolyte-free waterSousa, Lindomar Gomes de 20 May 2013 (has links)
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Previous issue date: 2013-12-17 / Eletrodos constitu?dos de ?-PbO2 foram preparados via eletrodeposi??o, mediante inclus?o dos ?ons Fe3+ e F- na mistura precursora, usando como substratos tela de a?o (ASTM 316) e tecido de carbono, visando a produ??o eletroqu?mica de oz?nio (PEO) em um reator filtro-prensa conduzida na aus?ncia de eletr?lito l?quido. A an?lise das micrografias de MEV para ambos substratos revelaram que em baixas concentra??es dos dopantes houve a forma??o de gr?os bem definidos com uma ?rea superficial uniforme. A an?lise de Raios-X para ambos substratos revelou o desfavorecimento da forma??o da fase ?-PbO2 para a maioria da concentra??o dos dopantes. Estudos cronopotenciom?tricos evidenciaram a estabilidade dos anodos quando sujeitados a intensa evolu??o de gases. Para o eletrodo dopado com 1 mM do ?on Fe3+, a efici?ncia de corrente da PEO foram de 10% e 9,5% com uma velocidade de gera??o de oz?nio de 1,35 g h-1 e 1,40 g h-1 para os substratos de tela de a?o e de tecido de carbono, respectivamente. Os resultados encontrados s?o promissores indicando uma viabilidade do uso desses eletrodos para aplica??o no tratamento de ?gua, por isso, empregou-se o oz?nio produzido eletroquimicamente para tratar ?gua residu?ria proveniente da produ??o de biodiesel na planta piloto da UFVJM. O tratamento oxidativo da ?gua residu?ria foi conduzido num reator em coluna de bolhas via rea??o direta (oz?nio molecular), indireta (radical hidroxila) e mista (O3/HO?) manipulando-se o pH do meio reacional.A caracteriza??o do efluente ozonizado foi efetuada monitorando-se o processo de degrada??o da mat?ria org?nica dissolvida via espectrofotometria. A cin?tica do processo de degrada??o seguiu o modelo de pseudo-primeira ordem. Foi verificado que a constante cin?tica sofre varia??o com o tempo de ozoniza??o revelando, portanto, uma varia??o da recalcitr?ncia com o tempo de rea??o. A demanda de energia requerida no processo de ozoniza??o foi caracterizada por uma energia el?trica por ordem (EEO) de 139 kW h m-3 ordem-1. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT
Electrodes comprised of ?-PbO2 were prepared by electrodeposition, by moans of the inclusion of Fe3+ and F- ions in the precursor mixture, using as substrates steel screen (ASTM 316) and carbon cloth in order to produce ozone in an filter-press electrochemical reactor conducted in the absence of liquid electrolyte. The analysis of SEM micrographs revealed that for both substrates at low dopants concentrations resulted in the formation of well-defined grains with a uniform surface area. X-rays analysis for both substrates showed the inhibition of formation of the ?-PbO2 phase for most of the dopant concentration. Cronopotenciometric studies revealed a good stability of the anodes when they were subjected to the intense gas evolution. For the electrode doped with 1 mM Fe3+, the current efficiency of EOP were 10% and 9.5% for an ozone generation rate of 1.35 g h-1 and 1.40 g h -1 using the steel screen and carbon cloth substrates, respectively. These results are promising, indicating a feasibility of using these electrodes for application in water purification, so the electrochemical ozone produced was applied to treat residuary water obtained from the biodiesel produced in the pilot plant of UFVJM. The oxidative chemical treatment of wastewater was conducted in a bubble column reactor via direct (molecular ozone), indirect (hydroxyl radical) and mixed (O3/HO?) oxidation reaction thrush manipulating the pH of the reaction medium. The characterization of ozonated effluent was assessed by means of monitoring the degradation of the dissolved organic matter using spectrophotometry. The kinetics of the degradation process followed a pseudo-first order model. It was found that the rate constant changes on the ozonation time thus indicating a recalcitrance variation with the reaction time. The energy demand required in the ozonation process was described by an electric energy per order (EEO) of 139 kW h m-3 order-1.
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Avalia??o de sistemas constitu?dos por pol?meros/ tensoativo/ EDTA na recupera??o avan?ada de petr?leo / Evaluation of systems constituted by polymers/ surfactant/ EDTA in enhanced oil recoverySantos, Joselisse Soares de Carvalho 19 October 2015 (has links)
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Previous issue date: 2015-10-19 / A recupera??o avan?ada de petr?leo tem sido foco de in?meras pesquisas buscando o melhoramento da recupera??o do ?leo in place dos reservat?rios, isto porque os reservat?rios maduros e/ou aqueles que possuem ?leos muito viscosos precisam de meios que auxiliem no escoamento e conseq?ente produ??o. Diante disto, foram estudadas as propriedades f?sico-qu?micas, entre estas propriedades verificaram-se o comportamento reol?gico e a tens?o superficial dos pol?meros, variando a concentra??o e a temperatura. Ap?s a obten??o da concentra??o de overlep, foi analisada a tens?o interfacial da solu??o de petr?leo/poliacrilamidas e, estas em presen?a de tensoativo e EDTA. Tamb?m, observou-se a permeabilidade destas solu??es, modificando a concentra??o. Com isso, o objetivo desta caracteriza??o foi observar a viabilidade destas solu??es nos processos de deslocamento de petr?leo em meio poroso. Os resultados obtidos mostraram que o aumento da ionicidade das poliacrilamidas promove um aumento da viscosidade no meio. No caso da temperatura seu aumento reduz a viscosidade para as poliacrilamidas de baixa ionicidade, a aumenta a viscosidade das poliacrilamidadas de alta ionicidade. Quanto a permeabilidade, verificou-se que os pol?meros ani?nicos apresentaram press?es mais elevadas em compara??o aos pol?meros de baixa ionicidade, e acredita-se que esse comportamento esteja relacionado ?s viscosidades destes pol?meros, que s?o mais altas. Na tens?o superficial observou-se a regi?o da concentra??o de overlep de cada pol?mero, consequentemente foi observado que as cargas i?nicas n?o influenciaram consideravelmente na redu??o das tens?es interfaciais entre o ?leo e as poliacrilamidas e constataram-se redu??es das IFT de todas as solu??es estudadas quando comparada ao caso ?gua/petr?leo. Tal resultado ? um bom ind?cio para seu uso no processo de recupera??o avan?ada de petr?leo. Finalmente, ao injetar as solu??es estudadas no meio poroso, verificou-se que as solu??es de pol?meros com maior ionicidade em presen?a de tensoativo e EDTA promoveram uma sinergia na recupera??o avan?ada de petr?leo, quando comparadas ?s solu??es contendo apenas pol?meros. / Enhanced oil recovery has been the focus of countless research projects
aiming for the improvement of the in place oil recovery from the reservoirs, especially
because mature fields and/or fields containing heavy oil require further assistance to
ensure oil flow and consequent production. Having that in mind, physical and chemical
properties such as the rheological behaviour and the superficial tension of polymers, for
different concentrations and temperatures, were studied. After obtaining the polymers
critical aggregation concentration (c.a.c.), the interfacial tension (IFT) between the
polyacrylamide/oil solutions was evaluated, as well as for the solutions containing
surfactant (SB) and EDTA. The permeability and the application of those solutions in
enhanced oil recovery of those solutions was also observed using the Botucatu arenite.
The results obtained demonstrated that the increase in the polymers ionicity promotes an
increase in the solution viscosity. An increase in temperature reduced the viscosity for the
low ionicity polyacrylamides, but caused an increase in the viscosity for some of the high
ionicity ones. Concerning permeability, the anionic polymers presented higher injection
pressure values when compared to the lower ionicity ones, and that behaviour is believed
to be related to the viscosities of those polymers, which are higher. Regarding superficial
tension, the c.a.c. region for each polymer was observed, and the conclusion was that the
ionic charges had little or no influence in the reduction of interfacial tensions between the
oil and the polymers, while the decrease in IFT for all solutions was observed when
compared to the system formed by water and oil. The aforementioned results are a good
indicator that the polymers studied are suitable for the enhanced oil recovery process. By
injecting the solutions into the porous media, it was observed that the solutions formed by
SB associated to EDTA improved the flow inside the porous media. The results indicated
that the enhanced oil recovery using the polymer/ surfactant/ EDTA solutions reached a
recovery factor of 18 % of the original oil. In addition, it could be observed that polymers
presenting the higher ionicity, associated to surfactant and EDTA, promoted a synergy in
the enhanced oil recovery when compared to the solutions containing only polymers.
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Ocorr?ncia de leite inst?vel na regi?o semi?rida do Rio Grande do Norte e sua correla??o com a qualidade do leiteFaria, Priscilla Fernandes de 05 August 2015 (has links)
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Previous issue date: 2015-08-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O objetivo deste trabalho foi identificar a ocorr?ncia de leite inst?vel n?o ?cido nasmesorregi?es oeste e central do Rio Grande do Norte, bem como avaliar a qualidade doleite. Foram analisadas 92 amostras, ao longo de 4 meses, provenientes de 23 tanques deresfriamento. Foi realizado o teste do ?lcool a 68%, 72% e 76%, al?m da mensura??o dopH, acidez, gordura, prote?na, s?lidos totais, nitrog?nio ureico, lactose, case?na e contagemde c?lulas som?ticas. A incid?ncia de LINA foi de 15,91%, e n?o houve diferen?asignificativa na composi??o do LINA em rela??o ao leite est?vel em nenhuma dasgradua??es alco?licas. Nenhuma amostra de LINA apresentou coagula??o na prova dafervura. Tais resultados permitem concluir que apesar das in?meras adversidades clim?ticase nutricionais existentes na regi?o, o LINA n?o representa um problema aparente / The unstable non acid milk (UNAM) is characterized by coagulation in the alcohol test and wanted acidity (14-18?D). Among Brazilian regions, the South and Southeast have the highest occurrence of LINA, which has been causing problems for both producers and for industries, due to the disposal or undervaluation of milk. In the Northeast there are few studies that indicate their occurrence and quality. The objective of this study was to identify the occurrence of unstable non-acid milk in the west and central mesoregions of Rio Grande do Norte, determine their physicochemical characteristics, test alcoholic graduations and evaluate their correlation with the quality of milk. 176 raw milk samples were analyzed in the period from September to December /2014 from 23 APASA?s cooling tanks, located in 7 cities of west and central mesoregions RN. The samples were collected in duplicate, one sample used for alcohol testing at 68, 72 and 76%, measurement of pH, acidity, electrical conductivity and boiling proof, made in LABOLEITE / UFRN; and the other sample containing Bronopol? preservative, was sent to the APCBRH (Cattle Breeders Association Paranaense Holstein) laboratory in Curitiba-PR, which were analyzed fat, protein, total solids, lactose, casein, urea nitrogen and somatic cell count. The test alcohol samples disapproved 31.82%, of which 30% proved to be non-acid, and 30% had high acidity. The samples were divided into three classes: Stable Milk, UNAM and acid milk. 3% Tukey test was used for comparison of stable milk components and UNAM and there was no significant difference between them. Both classes obtained averages within the standard required by IN 62. The average value of electric conductivity was 4.84 mS/cm for stable milk, 4.55 mS/cm for unstable and acid milk and 4.53 mS/cm for non-acid unstable milk. The electrical conductivity was positively correlated with alcohol stability of milk and negative correlation with acidity and pH. Could not observe direct relationship between the electrical conductivity and the somatic cell count.The boiling test was negative for all samples UNAM. It can be concluded that the incidence of UNAM in the studied region is low, although the predisposing factors such as heat stress, drought and nutritional deficiency. In conclusion, the UNAM has quality similar to stable milk, conform the norms required by Agriculture Ministry, and with adequate thermal stability, which proves that there is no reason to reject this milk by industry.
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Caracteriza??o f?sico-qu?mica, reol?gica e sensorial de iogurte obtido pela mistura dos leites bubalino e caprinoBezerra, Maria de F?tima 25 February 2010 (has links)
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Previous issue date: 2010-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Milk from different animals can be used for dairy production. Yoghurt is a popular fermented milk product and considered to be one of the greatest importance in terms of consumer acceptance and consumption. The present research deals with the production of strawberry set-type yoghurt by mixing goat and buffalo s milk and it has the objective of taking advantage of the intrinsic characteristics of each milk to produce a final product with desirable attributes. It was conducted by analyzing five experimental groups with different proportions of goat and buffalo s milk: C 100% goat s milk; 7C3B - 70% goat s milk and 30% buffalo s milk, 5C5B - 50% goat s milk and 50% buffalo s milk, 3C7B 30% goat s milk and 70% buffalo s milk; B - 100% buffalo s milk. Each group was evaluated for total
solids content and the acidification profile was monitored every 30 minutes by pH analysis. The yoghurt samples were analyzed for physical-chemical (pH, acidity, protein, fat, total and reducing sugars, ash and total solids), rheological (syneresis and viscosity) and sensory characteristics (appearance, odor, consistency and flavour). Samples with higher percentual of
bubaline milk reached Vm faster, but the time necessary for pH 4.6 (Te) were similar between groups. Statistical differences (p<0.05) were observed for fat and total solids content of
yoghurt, with superior values for groups higher proportions of buffalo s milk. The parameters of behavior reached by the model of Ostwald of Waale pointed yoghurt samples as non-Newtonian and pseudoplastic fluids. Yoghurt made only with goat s milk (C) had higher values (p<0.05) for syneresis, which can be explained by its fragile coagulum. Additionally, this group also had the lowest sensory scores for the attributes consistence and taste, while bubaline yoghurt (B) obtained the best acceptance indexes for all of the appraised parameters / O leite de diversos animais pode ser mat?ria-prima para produ??o de diferentes tipos de produtos l?cteos existentes no mercado. Dentre eles est? o iogurte, o qual ? considerado como um dos produtos de maior aceita??o e consumo. O presente trabalho visa estudar o processo de elabora??o de iogurte a partir de misturas de leite de cabra e de b?fala com adi??o de sabor morango. Pretende-se com isso aliar caracter?sticas intr?nsecas distintas dos dois tipos de leites de forma a obter um produto de elevada aceita??o com caracter?sticas f?sico-qu?micas e organol?pticas desej?veis. A presente pesquisa foi desenvolvida a partir de cinco grupos experimentais com diferentes propor??es de leite caprino e bubalino: C - 100%
leite de cabra, 7C3B - 70% leite de cabra e 30% leite de b?fala, 5C5B - 50% leite de cabra e 50% leite de b?fala, 3C7B - 30% leite de cabra e 70% leite de b?fala, B - 100% leite de b?fala. Inicialmente cada grupo foi avaliado quanto ao teor de s?lidos totais e foi determinado o pH das amostras retiradas a cada 30 minutos para acompanhamento da acidifica??o. Os iogurtes foram caracterizados quantos aos atributos f?sico-qu?micos (pH, acidez, prote?na, gordura, AR, ART, cinzas e s?lidos totais), reol?gicos (sinerese e viscosidade) e sensoriais (apar?ncia, odor, consist?ncia e sabor). As amostras com maior percentual de leite bubalino alcan?aram a taxa m?xima de acidifica??o (Vm) mais rapidamente, mas o tempo necess?rio para alcan?ar pH 4,6 foi similar entre os grupos. Diferen?as estat?sticas entre os grupos estudados foram percebidas no percentual de gordura e s?lidos totais, os quais apresentaram valores superiores para as formula??es com maior presen?a de leite de b?fala. Os ?ndices de comportamento alcan?ados pelo modelo de Ostwald de Waale apontam que os iogurtes s?o fluidos pseudopl?sticos. Al?m disso, o comportamento das curvas de fluxo e viscosidade
aparente em fun??o da taxa de cisalhamento indicam que os iogurtes se classificam como fluidos n?o Newtoniano. Os iogurtes obtidos a partir de leite de cabra (grupo C) apresentaram valores estatisticamente superiores (p< 0,05) para sinerese, o que pode ser conseq??ncia do fr?gil co?gulo formado. Adicionalmente, esse grupo, ao ser comparado com os demais, apresentou escores mais baixos para os atributos consist?ncia e sabor, enquanto o iogurte produzido apenas com leite bubalino (grupo B) obteve os melhores ?ndices de aceita??o para todos os par?metros avaliados
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Caracteriza??o de ?gua produzida na ind?stria de petr?leo para fins de descarte e otimiza??o do processo de separa??o ?leo/?gua / Characterization of produced water in the oil industry for disposal and optimization of oil water separation.Carvalho, Patr?cia Cristina de Ara?jo Puglia de 17 March 2011 (has links)
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Previous issue date: 2011-03-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The oil industry has several segments that can impact the environment. Among these,
produced water which has been highlight in the environmental problem because of the great
volume generated and its toxic composition. Those waters are the major source of waste in the
oil industry. The composition of the produced water is strongly dependent on the production
field. A good example is the wastewater produced on a Petrobras operating unit of Rio
Grande do Norte and Cear? (UO-RNCE). A single effluent treatment station (ETS) of this unit
receives effluent from 48 wells (onshore and offshore), which leads a large fluctuations in the
water quality that can become a complicating factor for future treatment processes. The
present work aims to realize a diagnosis of a sample of produced water from the OU - RNCE
in compliance to certain physical and physico-chemical parameters (chloride concentration,
conductivity, dissolved oxygen, pH, TOG (oil & grease), nitrate concentration, turbidity,
salinity and temperature). The analysis of the effluent is accomplished by means of a MP
TROLL 9500 Multiparameter probe, a TOG/TPH Infracal from Wilks Enterprise Corp. -
Model HATR - T (TOG) and a MD-31 condutivimeter of Digimed. Results were analyzed by
univariated and multivariated analysis (principal component analysis) associated statistical
control charts. The multivariate analysis showed a negative correlation between dissolved
oxygen and turbidity (-0.55) and positive correlations between salinity and chloride (1),
conductivity, chloride and salinity (0.70). Multivariated analysis showed there are seven
principal components which can explain the variability of the parameters. The variables,
salinity, conductivity and chloride were the most important variables, with, higher sampling
variance. Statistical control charts have helped to establish a general trend between the
physical and chemical evaluated parameters / A ind?stria do petr?leo possui v?rios segmentos que podem impactar o meio
ambiente. Dentre eles, a ?gua de produ??o, tem ganhado destaque na problem?tica ambiental
em virtude do grande volume gerado e de sua composi??o t?xica, sendo esta uma das maiores
fontes de res?duos da ind?stria do petr?leo. A composi??o da ?gua de produ??o ? fortemente
dependente do campo produtor. Um bom exemplo ? a ?gua produzida na Petrobras-Unidade
Operacional do Rio Grande do Norte e Cear? (UO-RNCE). Uma ?nica ETE (Esta??o de
Tratamento de Efluente) desta unidade recebe efluentes de 48 po?os (onshore e offshore) o
que leva a grandes varia??es na qualidade da ?gua resultando em um complicador aos futuros
processos de tratamento.O presente trabalho tem como objetivo realizar um diagn?stico de
uma amostra da ?gua produzida proveniente da UO RNCE em observ?ncia a determinados
par?metros f?sicos e f?sico-qu?micos (concentra??o em cloreto, condutividade, oxig?nio
dissolvido, pH, TOG (Teor de ?leos e graxas), concentra??o em nitrato, turbidez, salinidade e
temperatura). A an?lise do efluente foi realizada por meio de uma Sonda Multiparam?trica
modelo MP TROLL 9500, atrav?s do Infracal TOG/TPH da Wilks Enterprise Corp Modelo
HATR T (TOG) e ainda fazendo uso do condutiv?metro da Digimed, MD 31. Os dados
foram tratados atrav?s de an?lise estat?stica univariada e multivariada (an?lise de
componentes principais) associada os gr?ficos de controle estat?stico. A an?lise estat?stica
multivariada mostrou correla??es negativas entre oxig?nio dissolvido e turbidez (-0,55) e
correla??es positivas entre salinidade e cloreto (1), condutividade, cloreto e salinidade (0,70).
A an?lise multivariada indicou os sete componentes principais que podem explicar a
variabilidade dos par?metros. As vari?veis, salinidade, cloreto e condutividade foram as
vari?veis mais importantes, ou seja, de maior vari?ncia amostral. Com gr?ficos de controle
estat?stico foi poss?vel estabelecer uma tend?ncia geral entre os par?metros f?sico-qu?micos
avaliados
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Estrat?gia de gest?o ambiental baseada nos princ?pios da produ??o mais limpa : um estudo de caso focado no segmento da carcinicultura / Environmental management strategy based on principles of cleaner production: a case study in shrimps culture farmLima, Iran Marques de 14 April 2008 (has links)
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Previous issue date: 2008-04-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The objective of this scientific article is to introduce the opportunities of implementation of cleaner production (CP) in a shrimp culture farm. The methodology used for this was exploratory research implemented in a production unit located in the Northeast Brazil. The scientific article approaches since generic aspects of the technique about the management to use water, energy and the effluent characterization of this productive activity. It discusses quantitative aspects, environmental questions and chances of P+L during the productive process phases. The results points to input economy in the form of feed, soil correctives, medicines, and energy applied to the process, which range from 4% to 27%, emphasizing the small profit should be viewed as a source of considerable environment return. The authors conclude for the adoption property of this technique in this agribusiness segment, point out to the management importance of the input dosage in the quality of the final effluent, besides the adoption of a physical-chemistry remediation mechanism to the residual of Sodium metabissulphite used in the process of shrimp caught / O objetivo do trabalho ? apresentar uma estrat?gia de implementa??o da produ??o mais limpa (P+L) em uma fazenda de cultivo de camar?es. A metodologia utilizada foi pesquisa explorat?ria, realizada pela investiga??o via estudo de caso, implementada em uma unidade produtiva localizada no nordeste do Brasil. O trabalho aborda desde aspectos gen?ricos da t?cnica no que diz respeito ao gerenciamento do uso da ?gua, energia, e da caracteriza??o do efluente desta atividade produtiva. Discute aspectos quantitativos, considera??es ambientais, e oportunidades de P+L nas fases do processo produtivo. Os resultados apontam para economias de insumos sob a forma de alimentos, corretivos de solo, medicamentos, e energia aplicados ao processo, que variam de 4 a 27%, ressaltando-se que o pequeno ganho financeiro, deve ser encarado como uma fonte de consider?vel benef?cio ambiental. Os autores concluem pela propriedade da ado??o da t?cnica neste segmento do agroneg?cio, ressaltando a import?ncia do gerenciamento da dosagem de insumos na qualidade do efluente final, al?m da ado??o de um mecanismo de remedia??o f?sico-qu?mica para o residual de metabissulfito de s?dio utilizado na despesca
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Caracteriza??o estrutural de Perovskitas Lax-1AxCoO3 (x=0 e 0,2) ,dopadas com c?lcio e bario, por espectroscopia de absor??o de raios X (XAS).Gomes, Washington Charles de Macedo 09 September 2013 (has links)
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Previous issue date: 2013-09-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, the structures of LaCoO3, La0,8Ba0,2CoO3 and La0,8Ca0,2CoO3 perovskites
were characterized as a function of temperature (LaCoO3 structure being analyzed only at
room temperature). The characterization of these materials were made by X-Ray Absorption
Spectroscopy (XAS), in the cobalt K-edge, taking into account the correlated Einstein model
X-ray absorption fine structure (EXAFS). The first part of the absorption spectrum
corresponded the X-ray absorption near edge structure (XANES) and extended X-ray
absorption fine structure (EXAFS). These materials were prepared by the combustion method.
The combustion products were calcinated at 900 0C, for 6 hours in air. Noted that the sample
LaCoO3 at room temperature and samples doped with Calcium and Barium in the temperature
range of 50 K to 298 K showed greater distortion to monoclinic symmetry with space group
I2/a. However, the sample doped with barium at the temperatures 50 K, 220 K, and 260 K
showed a slight distortion to rhombohedral symmetry with space group R-3c. The La0,8Ca0,
2CoO3 structure was few sensitive to temperature variation, showing a higher local distortion
in the octahedron and a higher local thermal disorder. These interpretations were in
agreement with the information electronic structural on the XANES region and geometric in
the EXAFS region / Neste trabalho foram investigados estruturas de perovskitas LaCoO3, La0,8Ba0,2CoO3 e
La0,8Ca0,2CoO3 em fun??o de temperatura, sendo que a estrutura LaCoO3 foi analisada apenas
em temperatura ambiente. As caracteriza??es destes materiais foram realizadas pela
espectroscopia de absor??o de raios X (XAS) na borda K do cobalto levando em considera??o
modelo de Einstein correlacionado na estrutura fina de absor??o (EXAFS). A primeira parte
do espectro de absor??o de raios X corresponde absor??o de raios X pr?xima ? borda de
absor??o (XANES) e a outra estende ? espectroscopia da estrutura fina de absor??o (EXAFS).
Estes materiais foram preparados pelo m?todo de combust?o. Os produtos obtidos da
combust?o foram tratados termicamente por 9000C por 6 horas nesses materiais. Observou
que a amostra LaCoO3 em temperatura ambiente e as amostras dopadas com C?lcio e B?rio na
faixa de temperatura entre 50 K a 298 K apresentaram uma maior distor??o com simetria
monocl?nica com grupo espacial I2/a. No entanto, a amostra dopada com B?rio nas
temperaturas 50 K, 220 K e 260 K mostrou uma leve distor??o com simetria rombo?drica
com grupo espacial R-3c. A estrutura La0,8Ca0,2CoO3 foi pouco sens?vel com a varia??o de
temperatura, apresentando uma maior distor??o local no octaedro e uma maior desordem
t?rmica local. Estas interpreta??es est?o de acordo com as informa??es estruturais eletr?nica
na regi?o XANES e geom?trica na regi?o EXAFS
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