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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.
31

Removal and recovery of phosphorus from side-stream hydrolysis

Naduvath, Anu Paul January 2017 (has links)
The report formulates the experiments conducted to remove phosphorus from the return sludge wastewater subjected to side-stream hydrolysis. The experiments are conducted using the wastewater from the outlet of side-stream hydrolysis and is tested in a laboratory at the Duvbackens wastewater treatment plant in Gävle. Chemical precipitation is used in the experiments and displays remarkable results using magnesium chloride and calcium chloride as the precipitants. A successful removal rate of 79-99% is achieved through this method. The phosphate phosphorus content is chosen to be the criterion for estimating the phosphorus removal rate. Possible parametric variations are also reviewed in the report. The decline in ammonium nitrogen is also studied alongside. Struvite and calcium phosphate are the possible precipitates and are recovered with the prospect of recycling. Both the precipitates are known as slow fertilizers and are used in the agricultural industry. If recovered by proper means, these precipitates can reduce the pressure on phosphate industry and on naturally occurring phosphate rocks. Calcium phosphate is selected among the precipitation methods for its rapid reaction and its minimum response to parametric variations. It also expresses a faster settling property with a clear solution after precipitation. The removal and recovery of phosphorus from the side-stream hydrolysis is evaluated with a notion to operate in a pilot scale.
32

The effect of calcium chloride postharvest dips and concentrations of the improvement of storage and shelf-life of 'classic round' tomatoes (solanum lycopersicum, L.)

Matsunyane, Keitumetse Delician January 2022 (has links)
Thesis (M.Sc. (Horticulture)) -- University of Limpopo, 2017 / Tomato is popularly consumed as fresh vegetable or processed product due to its nutritional and health benefits. However, due to its high perishability, tomato cannot be stored for longer duration. Therefore, the aim of this study was the determination of appropriate dipping times into different calcium chloride concentrations to preserve the postharvest quality, storage and the shelf-life of tomato fruit. 'Classic round' tomato fruit were harvested at their pink maturity stage. The experiment was carried out as a completely randomized design (CRD), factorial arranged as 4 × 3 × 8. Treatment factors were: 4 × CaCl2 (0, 0.0045, 0.01 and 0.03%), 3 × dipping times (0, 30 and 60 minutes) and 8 × shelf-life (0 - 7 days). Fruit were stored at 15⁰ C for 30 days, thereafter, held under room temperature for 0 - 7 days of shelf-life while collecting data. During shelf-life period, fruit were evaluated for weight loss, firmness, colour, TSS, TA, pH, physiological and pathological disorders. The interaction between the treatments and dipping times showed a significant effect on weight loss, firmness, colour parameters [L*, b*, chroma and hue angle (⁰)], total soluble solids (TSS), titratable acidity (TA), pH, decay and black mould occurrence. However, significant interactive effects were not shown on a* colour component and chilling injury. In conclusion, calcium chloride (CaCl2) improved the quality and shelf-life of 'Classic round' tomato fruit. Calcium chloride concentration 0.01% was effective at 30 minutes dipping time, meanwhile, 0.03% CaCl2 was effective at 60 minutes dipping time. Therefore, 0.01 and 0.03% can be recommended for commercial preservation use for tomato fruit quality and shelf-life. / Agricultural Research Council-Tropical and Subtropical Crops (ARC-TSC) and National Research Foundation (NRF)
33

Aplicação de cálcio em pré-colheita de atemoia ‘Thompson’: trocas gasosas, óleo essencial de folhas e características físico-químicas dos frutos / Calcium applications in pre-harvest atemoia 'Thompson': gas exchange, essential oil of leaves and physico-chemical characteristics of fruits

Parreiras, Nathália de Souza [UNESP] 08 June 2017 (has links)
Submitted by NATHÁLIA DE SOUZA PARREIRAS null (nathaliaparreiras@ig.com.br) on 2017-08-04T14:35:24Z No. of bitstreams: 1 tese nathalia 04-08-17 para impressão.pdf: 1835096 bytes, checksum: 83b6c0e6cef99c4619caafcd238490f8 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-08-04T20:20:09Z (GMT) No. of bitstreams: 1 parreiras_ns_dr_bot.pdf: 1835096 bytes, checksum: 83b6c0e6cef99c4619caafcd238490f8 (MD5) / Made available in DSpace on 2017-08-04T20:20:09Z (GMT). No. of bitstreams: 1 parreiras_ns_dr_bot.pdf: 1835096 bytes, checksum: 83b6c0e6cef99c4619caafcd238490f8 (MD5) Previous issue date: 2017-06-08 / O cálcio é um nutriente essencial às plantas, participando das funções estruturais da parede celular e da membrana, como contra cátion para ânions orgânicos e inorgânicos no vacúolo e desempenha papel essencial como mensageiro intracelular no citosol. A concentração de cálcio no citoplasma das células vegetais aumenta em resposta a várias condições de desenvolvimento e fatores ambientais. Essas alterações na concentração de cálcio no citosol da célula são cruciais para as respostas fisiológicas da planta. O presente estudo objetivou avaliar se a aplicação de concentrações de cloreto de cálcio afetam as trocas gasosas, atividade das enzimas antioxidantes, perfil químico do óleo essencial extraído das folhas, tamanho, firmeza e aspectos químicos ligados à qualidade dos frutos de Annona × atemoya Mabb. cv. ‘Thompson’. O experimento foi conduzido no sítio Paraizinho localizado no munícipio de Pardinho-SP em pomar comercial. O delineamento experimental foi em blocos casualisados, sendo quatro concentrações de cloreto de cálcio (0%, 0,5%, 1,0% e 1,5% de CaCl2) aplicados via foliar a cada 45 dias e seis blocos, com uma planta por parcela experimental. Foram avaliadas as seguintes características: trocas gasosas, enzimas antioxidantes, diâmetro e comprimento dos frutos, firmeza, pH, acidez titulável, sólidos solúveis, relação sólidos solúveis/acidez, açúcares, amido, teor de ácido ascórbico,teor de cálcio, perfil químico dos óleos essenciais. As dosagens de CaCl2 aumentaram a assimilação de CO2, a eficiência no uso da água, a eficiência de carboxilação, a firmeza e a acidez dos frutos, reduzindo os teores de ácido ascórbico e modificando o perfil químico dos óleos essenciais. / Calcium is an essential nutrient for plants, participating in the structural functions of the cell wall and membrane, as against cation for organic and inorganic anions in the vacuole and plays an essential role as a messenger in intracellular cytosol. The concentration of calcium in the cytoplasm of plant cells increases in response to several conditions of development and environmental factors. These changes in the concentration of calcium in the cytosol of the cell are crucial to the physiological responses of the plant. The present study aimed to evaluate the implementation of different calcium concentrations in gas exchange, chemical profile of essential oil extracted from the leaves, size, firmness and chemical aspects linked to the quality of the Annona × atemoya Mabb The experiment was conducted at the Paraisinho site located in the municipality of Pardinho-SP in a commercial orchard. The experimental design was in randomized blocks, being 4 concentrations of calcium chloride (0%, 0.5%, 1.0% and 1.5% CaCl2) applied via by foliar every 45 days and six replications of a plant. The effect of the treatments was evaluated by assessing the following: gas exchange, diameter and length of fruits, firmness, pH, soluble solids, titratable acidity, soluble solids/acidity, sugars, starch, ascorbic acid content and chemical profile of essential oils. The levels of CaCl2 increased CO2 assimilation, water use efficiency, carboxylation efficiency, the firmness and the acidity of the fruit, reducing the levels of Ascorbic acid and modifying the chemical profile of essential oils.
34

Estudo do efeito do tipo de corte, adiÃÃo de cloreto de cÃlcio e Ãcido ascÃrbico nas caracterÃsticas fÃsicas, fÃsico-quÃmicas e microbiolÃgicas do abacaxi minimamente processado / Physical appearance, physical and chemical nd microbiology minimally processed pineapple

Gleucia Carvalho Silva 20 March 2001 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Devido a tendÃncia mundial de consumo de produtos in natura ou o mais prÃximo destes, os produtos minimamente processados vÃm apresentando um acentuado destaque no mercado consumidor. Este trabalho teve como objetivo avaliar os efeitos do corte e a adiÃÃo e cloreto de cÃlcio (CaCl2) e Ãcido ascÃrbico nas caracterÃsticas fÃsico-quimicas, fÃsicas e microbiolÃgicas do abacaxi minimamente processado. Os equipamentos, utensÃlios e embalagens foram higienizados com soluÃÃo de hipoclorito de sÃdio a 200ppm por 30 minutos. A higienizaÃÃo da estrutura fÃsica da unidade de processamento foi realizada com a mesma soluÃÃo secada naturalmente. Amostras de abacaxis âpÃrolaâ provenientes do Estado da ParaÃba foram adquiridas no CEASA em Fortaleza-Cearà e submetidas Ãs etapas de prÃ-lavagem, lavagem com soluÃÃo de hipoclorito de sÃdio (200ppm por 2 minutos) e armazenadas a 12ÂC, objetivando a estabilizaÃÃo da temperatura no interior dos frutos. Sob uma temperatura de 12ÂC, os frutos foram descascados e cortados nas formas de trapÃzio e fatia, sendo entÃo submetidos a trÃs tratamentos: I) efeito do tipo de corte; II) efeito do cÃlcio (soluÃÃo com 0%, 1% e 2,5% de CaCl2) e II) efeito do Ãcido ascÃrbico (soluÃÃo com 0ppm, 2000ppm e 3000ppm de Ãcido ascÃrbico). Os frutos cortados foram imersos nestas soluÃÃes, drenado o excesso de Ãgua e armazenados por 16 dias a 4ÂC + 1ÂC e 99% UR. A intervalos de quatro dias, foram coletadas amostras e submetidas Ãs anÃlises fÃsico-quÃmicas, fÃsicas e microbiolÃgicas. Ao final dos experimentos concluiu-se que os abacaxis cortados em fatia, tratados com 1% de cloreto de cÃlcio e 3000ppm de Ãcido ascÃrbico sÃo os mais indicados para o processamento mÃnimo, jà que preservaram suas caracterÃsticas de qualidade. / Because of the World trend about the consumption of â in naturaâ products or products similar to these, the products with minimum processing have been presenting a high distinction in the consuming market this work had the objective of evaluate the effects of calcium chloride (CaCl2) and ascorbic acid removal and addition in the physical chemistry, physical and microbiological characteristics of pineapple with minimum processing. The equipments, tools and packages were higienized with 200 ppm sodium hipochloride solution for 30 minutes and the physical estructure was left in contact until drying âpÃrolaâ pineapple samples from the state of ParaÃba were acquired in the supplying center â CEASA in Fortaleza, Cearà and were submitted to pre-washing, washing, with 200 ppm sodium hipochloride for 2 minutes phases and stored in 12ÂC with the objective of temperature stabilization inside fruit. Under temperature of 12ÂC fruit were peeled, cut in trapeze and slice shapes and were submitted to 3 treatments: I) kind of cut effect; II) calcium effect (solution with 0%, 1% and 2,5% of CaCl2) and III) ascorbic acid effect (solution with 0 ppm, 2000 ppm and 3000 ppm of ascorbic acid). The cut fruit were imersed in these solutions the water excess was drained and were stored for 16 days in 4ÂC  1ÂC, in gaps of 4 days, samples were collected and submitted to physical chemistry, physical and microbiological analyses. By the end if experiments it was concluded that pineapple cut in slices treated with 1% of calcium chloride and 300 ppm of ascorbic acid are the most indicated to the minimum processing because they preserved their quality characteristics.
35

Processamento mínimo de mamão (Carica papaya L.): efeitos de aditivos e atmosfera modificada na qualidade do produto. / Minimum processing of papaya (Carica papaya L.): effects of addictive and modified atmosphere in the product quality

Silvana Rodrigues Rabelo de Andrade 22 November 2006 (has links)
Este trabalho teve como objetivo avaliar as alterações fisiológicas, físicoquímicas, microbiológicas e sensoriais em mamões minimamente processados, submetidos a tratamentos químicos e atmosfera modificada passiva e ativa. No primeiro experimento foram determinadas a atividade respiratória e produção de etileno em mamões minimamente processados tratados com CaCl2 (1%); ácido ascórbico (0,5%); combinação de CaCl2 (1%) e ácido ascórbico (0,5%); e controle (sem aplicação de tratamento químico). O produto final foi armazenado a 6°C (±1°C) e 90% (±5%) de Umidade Relativa (UR) por um período de 6 dias. Os mamões processados que tiveram a adição de cloreto de cálcio obtiveram atividade respiratória significativamente menor a partir do 1º dia de armazenamento, mostrando que o CaCl2 (1%) pode colaborar para o prolongamento da vida útil do fruto processado. O segundo experimento visou avaliar a qualidade final e o período de conservação de mamões minimamente processados submetidos a 3 tipos de tratamentos químicos: CaCl2 (1%); ácido ascórbico (0,5%); a combinação de CaCl2 (1%) e ácido ascórbico (0,5%); e o controle (sem aplicação de tratamento químico), os quais foram acondicionados em embalagem de polietileno tereftalato rígida (PET) a 6°C por um período de 9 dias. Os mamões tratados com CaCl2 (1%) e a combinação de CaCl2 (1%) e ácido ascórbico (0,5%) preservaram o teor de açúcares, coloração, textura e as caracteristicas sensoriais durante todo o período de armazenamento avaliado (9 dias), enquanto que os tratados com ácido ascórbico tiveram a textura prejudicada evidenciada pela maior solubilização da pectina, denotando maior amolecimento dos tecidos. Os resultados mostraram que a adição de ácido ascórbico não foi eficaz para a preservação da qualidade de mamões minimamente processados e prolongamento da sua vida útil. As contagens de bactérias psicrotróficas mantiveram-se dentro dos limites aceitáveis para todos o tratamentos aplicados. O terceiro experimento avaliou o efeito do uso de atmosfera modificada passiva e ativa na qualidade de mamões minimamente processados, tratados com a combinação de CaCl2 (1%) e ácido ascórbico (0,5%). Após o processamento, os mamões, previamente tratados, foram submetidos a três tipos de acondicionamento: bandejas de poliestireno rígida, recobertas com filme de polipropileno 32 μm, sem e com injeção de gás (5% O2 + 10% CO2) e embalagem de polietileno tereftalato rígida (PET), com tampa, a qual foi utilizada como controle. Foram realizadas análises de O2 e CO2, físico-químicas, sensoriais e microbiológicas. Os mamões acondicionados em PET apresentaram pouca modificação gasosa porém mantiveram as características físico-químicas, sensoriais e microbiológicas, durante todo período de armazenamento avaliado (9 dias). Isto mostrou que a combinação de tratamento químico CaCl2 (1%) e ácido ascórbico (0,5%) foi eficaz e influenciou diretamente nos parâmetros avaliados. Os mamões minimamente processados acondicionados em filme de polipropileno com e sem injeção de gás, apresentaram comportamento semelhante para a maioria dos parâmetros físico-químicos e sensoriais (sabor e aparência), sendo que, a partir do 6°dia de armazenamento, foi constatada coloração alaranjada mais intensa (escurecimento da polpa) a qual se refletiu diretamente na aparência do produto. O uso de atmosfera modificada ativa mostrou-se eficiente no retardamento da proliferação de microorganismos psicrotróficos. / This work had as objective to evaluate the physiologic, physiochemical, microbiological and sensorial alterations in in minimally processed papayas, submitted to chemical treatments and passive and active modified atmosphere. In the first experiment, the respiratory activity and ethylene production were analized in minimally processed papayas treated with CaCl2 (1%); ascorbic acid (0,5%); the combination of CaCl2 (1%) and ascorbic acid (0,5%); and control (without application of chemical treatment). The final product was stored at 6°C (±1°C) and 90% (±5%) of relative humidity for a period of 6 days. The results showed that processed papayas treated with chloride of calcium obtained a significantly smaller respiration activity from the 1st storage day, showing that CaCl2 (1%) may collaborate on the prolongation of the processed fruit shelf life. The second experiment had as objective to evaluate the final quality and the period of conservation of minimally processed papayas submitted to 3 types of chemical treatments: CaCl2 (1%); ascorbic acid (0,5%); the combination of CaCl2 (1%) and ascorbic acid (0,5%); and the control (without application of chemical treatment), which were conditioned in rigid polyethylene terephthalate (PET) packages at 6 C° for a period of 9 days. The papayas treated with CaCl2 (1%) and the combination of CaCl2 (1%) and ascorbic acid (0,5%) preserved some physiochemical characteristics like the sugar rate, texture and color and sensorial characteristics during the whole period of the appraised storage (9 days), while the treatements with ascorbic acid had the texture prejudiced, presenting softening in the tissue. The results showed that the addition of ascorbic acid was ineffective for the preservation of the minimally processed papayas quality and the prolongation of the shelf life. The countings of psychotrophic bacteria stayed inside of the acceptable limits for all the applied treatments. The third experiment had as objective to evaluate the effect of the passive and active modified atmosphere using in the minimally processed papayas quality, treated with the combination of CaCl2 (1%) and ascorbic acid (0,5%). After the processing, the papayas, previously treated, were submitted to three package types: rigid trays of polystyrene, covered with a polypropylene film 32 μm, with and without injection of gas (5% O2 + 10% CO2) and packages of rigid polyethylene terephthalate (PET), with cover, which was used as control. Physical-chemical, sensorial, microbiological, O2 and CO2 analyses were accomplished. The papayas conditioned in PET presented little gaseous modification but maintained the physico-chemical, sensorial and microbiological characteristics, during all the periods of storage (9 days). The experiment showed that the combination of CaCl2 (1%) and ascorbic acid (0,5%) was effective and influenced the appraised parameters. The minimally processed papayas conditioned in polypropylene film with and without injection of gas, presented similar behavior for most of the physicalchemical and sensorial parameters (taste and appearance), and, starting from the 6 day of storage, more intense orange coloration was verified (bronwning of the pulp) which was reflected directly in the appearance of the product. The use of active modified atmosphere was shown efficient in the retardation of the psychotrophic organisms proliferation.
36

Injeção post-rigor de cloreto de cálcio no músculo semimembranoso de novilhos suplementados com zilpaterol : propriedades físico-químicas e sensoriais da carne / Post-injection accuracy of calcium chloride in semimembranosus muscle of steers supplemented with zilpaterol : physico-chemical and sensory characteristics of meat

Pflanzer Júnior, Sérgio Bertelli, 1983- 02 September 2012 (has links)
Orientador: Pedro Eduardo de Felicio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T15:31:41Z (GMT). No. of bitstreams: 1 PflanzerJunior_SergioBertelli_D.pdf: 1046006 bytes, checksum: 2711bfce1310c3e6cdd951debd20fb7d (MD5) Previous issue date: 2012 / Resumo: Dois estudos foram conduzidos para determinar o efeito da injeção de cloreto de cálcio nas características de palatabilidade e na estabilidade da cor de bifes de coxão mole (M. Semimembranoso) de bovinos suplementados com hidrocloreto de zilpaterol (HZ). No estudo 1 (palatabilidade), 466 bovinos foram divididos em 2 grupos, não-suplementados (n = 233) e suplementados (8,3 mg/kg de HZ nos últimos 20 dias do confinamento; n = 233). Após o abate e resfriamento, 39 carcaças USDA Select foram destinadas aleatoriamente para o teste (não-suplementados = 19; HZ = 20). No estudo 2 (estabilidade da cor), foram utilizados, 20 das 39 carcaças, em igual número de não-suplementados (n = 10) e suplementados HZ (n = 10). Os cortes de coxão mole das duas meias carcaças foram enviados para o laboratório, onde foram destinados alternadamente para os tratamentos não-injetado ou injetado com cloreto de cálcio (5% do peso com solução a 200 mM CaCl2 ). No estudo 1 foram avaliados o comprimento de sarcômero, índice de fragmentação miofibrilar, maciez instrumental (força de cisalhamento por Warner Bratzler - WBSF) e atributos sensoriais dos bifes de coxão mole maturados por até 28 dias. No estudo 2 foram avaliadas a composição centesimal, atividade redutora da metamioglobina (MRA), cor visual e instrumental e oxidação lipídica (TBARS) dos bifes de coxão mole maturados por até 21 dias seguidos da exposição em ¿display¿ por 4 dias. No estudo 1 não houve diferença (P > 0,05) do comprimento de sarcômero entre tratamentos com ou sem HZ. Amostras de animais não suplementados com HZ e amostras injetadas com cloreto de cálcio apresentaram maiores (P < 0,05) índices de fragmentação miofibrilar em relação a suplementados e a não-injetados, respectivamente. A suplementação com HZ não afetou (P > 0,05) as perdas de peso pela exsudação na embalagem, bem como a perda na cocção. A utilização de cloreto de cálcio aumentou (P < 0,05) as perdas de peso. O uso de HZ aumentou (P < 0,05) a WBSF somente dos bi fes maturados por 7 dias. A injeção de cloreto de cálcio em amostras de animais suplementados com HZ anulou (P > 0,05) a diferença na WBSF após 7 dias de maturação e também reduziu (P < 0,05) a WBSF nas amostras dos não suplementados. O HZ não afetou (P > 0,05) as características sensoriais dos bifes maturados por 14 ou 21 dias. Amostras injetadas foram mais macias (P < 0,05) do que as nãoinjetadas, após a maturação por 14 dias, entretanto não houve diferença (P > 0,05) nas maturadas por 21 dias para os atributos sensoriais. Estudo 2: animais tratados com HZ resultaram em carne de cor vermelho-cereja mais claro, maior valor de L * e menores escores de descoloração (P < 0,05). No final da exposição em ¿display¿, os bi fes de animais suplementados com HZ tiveram maiores valores de a * e b * que os controle (P < 0,05). A injeção de CaCl2 resultou em carne de cor vermelha mais intensa e com maiores escores de descoloração (P < 0,05) em amostras maturadas por 14 e 21 dias, mas não influenciou (P > 0,05) a cor aos 7 dias. O valor de L * não foi afetado pela injeção de CaCl2 (P > 0,05). Porém, ao final do período de exposição, as amostras injetadas apresentaram menores valores de a * b * (P < 0,05) que aquelas não-injetadas. A medida que se estendem os períodos de maturação a carne apresentou-se mais escura e com maiores escores de descoloração (P < 0,05). Além disso, a maturação e a exposição continuadas diminuíram (P < 0,05) os valores de a* e b* em ambos os tratamentos de suplementação e injeção. A oxidação lipídica, medida por TBARS, não foi afetada (P > 0,05) pela suplementação com HZ. A injeção de CaCl2 aumentou (P < 0,05) os valores de TBARS. A suplementação dos novilhos com zilpaterol reduziu a maciez das amostras em relação ao grupo não-suplementado. Entretanto a maturação por 14 dias, ou por 7, dias combinada com o tratamento pelo CaCl2 , pode equiparar as médias de maciez objetiva. Na primeira alternativa, o HZ contribuiu para uma maior estabilidade da cor relativamente aos não suplementados, e na segunda, não ocorreu alteração da cor em decorrência do CaCl2 injetado / Abstract: Two studies were conducted to determine the effect of calcium chloride injection on the palatability traits and color stability of steaks from inside round (M. Semimembranosus) of steers supplemented with zilpaterol hydrochloride (ZH). In study 1 (palatability), 466 steers were divided into two groups, non-supplemented and supplemented (8.3 mg/kg of ZH in the last 20 days of feedlot). After slaughter and cooling, 39 USDA Select grade carcasses were randomly destined for the test (non-supplemented = 19; ZH = 20). In study 2 (color stability), 20 from 39 carcasses, previously selected, were randomly destined for the test (non- supplemented = 10, ZH = 10). The inside round of both half-carcasses were sent to the laboratory where they were alternately selected to serve as non-injected or injected with calcium chloride (5 % with 200 mM CaCl2 solution). In study 1 it were evaluated the sarcomere length, myofibrillar fragmentation index, instrumental tenderness (shear force by Warner Bratzler - WBSF) and sensory traits of inside round steaks aged up to 28 days. In study 2 it were evaluated the proximate composition, metmyoglobin reducing activity, visual and instrumental color and lipid oxidation (TBARS) of inside round steaks aged up to 21 days followed by exposure in the display for 4 days. In study 1 there is no difference (P > 0.05) in treatments with or without ZH for sarcomere length. Samples of not ZH supplemented animals and injected samples had higher (P < 0.05) myofibrillar fragmentation index, than supplemented and non-injected, respectively. The ZH supplementation did not affect (P > 0.05) the losses during aging and cooking. The CaCl2 injection increased (P < 0.05) both losses. The use of ZH increased (P > 0.05) WBSF of inside round steaks aged 7 d, however samples aged 14 d did not differ (P > 0.05). The CaCl2 injection in samples from ZH supplemented steers cancelled (P > 0.05) the difference for WBSF after 7 d of aging and reduced (P < 0.05) WBSF in samples from non-supplemented. The ZH did not affect (P > 0.05) sensory traits of steaks aged 14 and 21 d. Injected samples were more tender (P < 0.05) than non-injected after 14 d aging, however there was no difference (P > 0.05) in steaks aged 21 d for sensory traits. In study 2 ZH steaks were lighter cherry red, had higher L* values, and had lower discoloration scores (P < 0.05). At the end of display, ZH steaks had greater (P < 0.05) a* and b* values than non-supplemented. CaCl2 injection resulted in redder beef color, and increased discoloration scores (P < 0.05) in samples aged 14 and 21 d, however it did not affect color traits on d 7 (P > 0.05). L* values were not affected by CaCl2 (P > 0.05), but at the end of display, injected samples had lower a* and b* values than noninjected samples (P < 0.05). Increasing aging and display time resulted in redder color and greater discoloration scores (P < 0.05). Moreover aging and display time decreased (P < 0.05) a* and b* values from both treatments of the two sources of variation. Lipid oxidation, evaluated by TBARS, was not affected by ZH (P > 0.05). The CaCl2 injection increased (P < 0.05) TBARS values. The ZH supplementation decreased tenderness of inside round steaks, however 14 d aging, or 7 d aging combined with CaCl2 injection, can even objective tenderness means, and in the last one, there is no effect in color traits due to CaCl2 injection, as it happens on d 14 and 21 of aging / Doutorado / Tecnologia de Alimentos / Doutor em Tecnologia de Alimentos
37

Redução de sódio em salsichas com alto teor de carne de frango mecanicamente separada = efeito de sais substitutos e derivados de alho sobre atributos de qualidade e segurança / Sodium reduction in frankfurters with high content of mechanically deboned poultry meat : effect of salts substitutes and garlic derivatives on quality and safety attributes

Horita, Claudia Nakamura, 1972- 02 September 2015 (has links)
Orientador: Marise Aparecida Rodrigues Pollonio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T11:20:08Z (GMT). No. of bitstreams: 1 Horita_ClaudiaNakamura_D.pdf: 2358356 bytes, checksum: 74a6a23d8840d17c6ccb1891f15638a6 (MD5) Previous issue date: 2015 / Resumo: A redução do consumo de sódio tem sido recomendado por vários órgãos da saúde em função da correlação positiva entre ingestão de sódio e o desenvolvimento de doenças como a hipertensão arterial, cardiovasculares e renais. Produtos cárneos emulsionados cozidos, principalmente salsichas, estão entre os mais consumidos no Brasil e apresentam elevados teores de sódio. Em algumas categorias de salsichas, matérias-primas menos nobres são adicionadas para reduzir o custo, dentre elas a carne mecanicamente separada de aves (CMS) permitidas em concentrações de até 60%. Cloreto de sódio é um ingrediente multifuncional, pois confere propriedades sensoriais, conservantes e tecnológicas em produtos cárneos. Adicionalmente, em formulações contendo alto teor de CMS sua redução pode ser ainda mais desafiadora pela perda de propriedades funcionais da matriz cárnea (presença de proteínas de menor funcionalidade, porções da medula óssea, alto teor de colágeno e gordura). Desta forma, este trabalho teve como objetivos estudar a influência da redução de sódio na qualidade de salsichas com alto teor de CMS. O trabalho foi dividido em três etapas. Na primeira etapa, blends de cloreto de potássio e cálcio, com força iônica equivalente a 2% NaCl, foram utilizados para substituir 25% ou 50% do NaCl em salsichas contendo 60% de CMS. O objetivo desta etapa foi avaliar o efeito da adição dos blends de sais sobre as propriedades físico-químicas e sensoriais das salsichas. Foram determinados: teor de sódio, Aw, estabilidade de emulsão (batter), avaliação de cor instrumental, perfil de textura, microestrutura e teste de aceitação sensorial. Na segunda etapa, uma formulação contendo blend de sais para substituir 50% NaCl foi selecionada com base nos dados da primeira etapa.e adicionada de derivados de alho (fresco, em pó, óleo comercial e extrato obtido via líquido pressurizado). O objetivo foi investigar os efeitos dos derivados de alho como antioxidantes e antimicrobianos nas formulações de salsichas. As determinações realizadas foram a mesmas da primeira etapa, com exceção da microestrutura e acrescidas da quantificação de Substâncias Reativas ao Ácido Tiobarbitúrico e análises microbiológicas durante 60 dias sob refrigeração. Finalmente, para as mesmas formulações de salsichas, uma terceira etapa foi realizada para avaliar o efeito dos derivados de alho como realçadores de sabor por meio da Análise Descritiva Quantitativa e Teste de Aceitação, utilizando-se duas amostras comerciais para efeito comparativo. Alho fresco e extrato de alho PLE, nas concentrações de 1% e 0,02% respectivamente, apresentaram propriedades antioxidantes e antimicrobianas durante a vida útil das salsichas. Dezoito descritores caracterizaram as amostras das salsichas avaliadas pelos assessores na análise descritiva quantitativa. De forma geral, os tratamentos do estudo apresentaram maior intensidade de sabor e aroma de alho e as amostras comerciais apresentaram aroma e sabor defumado. No teste de preferência, as salsichas comerciais foram as mais aceitas para impressão global, no entanto, salsichas elaboradas para o estudo apresentaram muitas similiaridades entre si em seus perfis sensoriais. Assim, a adição de derivados de alho em salsichas com alto teor de carne mecanicamente separada e adicionada de blends de sais substitutos de NaCl mostraram ser uma alternativa promissora neste seguimento / Abstract: The positive correlation between salt intake and the development of diseases including hypertension, and cardiovascular and renal disorders has led health authorities to recommend the reduction of sodium intake. Cooked emulsified meat products, mainly sausages, have high sodium levels and are among the most consumed products in Brazil. In some types of sausages, the mechanically deboned poultry meat (MDPM) stands out as less noble materials used to reduce costs, allowed in concentrations of up to 60%. Sodium chloride is a multi-functional ingredient, since it provides sensory, preservative, and technological properties in meat products. Sodium reduction can be even more challenging in formulations containing high MDPM levels, due to loss of functional properties of the meat matrix (presence of proteins of lower functionality, portions of the bone marrow, high collagen and fat contents). Thus, this study aimed to investigate the effect of sodium reduction on the quality of sausages with high MDPM content. The study was divided into three stages. In the first step, blends of potassium chloride and calcium chloride with ionic strength equivalent to 2% NaCl were used to replace 25% or 50% of NaCl in sausages containing 60% MDPM. The purpose of this step was to evaluate the effect of the addition of salt blends on the physicochemical and sensory characteristics of the sausages. The following parameters were investigated: sodium content, Aw, emulsion stability (batter), instrumental color, texture profile, microstructure, and sensory acceptance. In the second step, a formulation containing a salt blend to replace 50% NaCl was selected from the first step, and garlic derivatives (fresh, powder, commercial oil, extract obtained by pressurized liquid extraction) were added. The objective was to investigate the effects of garlic derivatives as antioxidant and antimicrobial agents in the sausage formulations. The determinations were the same as the first step, except for microstructure, plus measurement of Thiobarbituric Acid Reactive Substances and microbiological analyses during 60 days of refrigerated storage. Finally, a third step was carried out to evaluate the effect of garlic derivatives as flavor enhancers through quantitative descriptive analysis and acceptance tests, using two commercial samples for comparison. Fresh garlic and garlic PLE extract at concentrations of 1% and 0.02%, respectively, presented antioxidant and antimicrobial properties throughout the shelf life of the sausages. The sausage samples were characterized by eighteen descriptors selected by the assessors in the quantitative descriptive analysis. In general, the treatments had higher flavor intensity and garlic flavor, while the commercial samples exhibited smoky aroma and flavor. In the preference test, the commercial sausages were the most accepted for overall impression, and the sausages prepared for the study presented very similar sensory profiles. Thus, the addition of garlic derivatives in sausage formulations containing high mechanically separated poultry and blends of salt substitutes proved to be a promising alternative in this field / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos
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Processamento mínimo de mamão (Carica papaya L.): efeitos de aditivos e atmosfera modificada na qualidade do produto. / Minimum processing of papaya (Carica papaya L.): effects of addictive and modified atmosphere in the product quality

Andrade, Silvana Rodrigues Rabelo de 22 November 2006 (has links)
Este trabalho teve como objetivo avaliar as alterações fisiológicas, físicoquímicas, microbiológicas e sensoriais em mamões minimamente processados, submetidos a tratamentos químicos e atmosfera modificada passiva e ativa. No primeiro experimento foram determinadas a atividade respiratória e produção de etileno em mamões minimamente processados tratados com CaCl2 (1%); ácido ascórbico (0,5%); combinação de CaCl2 (1%) e ácido ascórbico (0,5%); e controle (sem aplicação de tratamento químico). O produto final foi armazenado a 6&#176;C (&#177;1&#176;C) e 90% (&#177;5%) de Umidade Relativa (UR) por um período de 6 dias. Os mamões processados que tiveram a adição de cloreto de cálcio obtiveram atividade respiratória significativamente menor a partir do 1º dia de armazenamento, mostrando que o CaCl2 (1%) pode colaborar para o prolongamento da vida útil do fruto processado. O segundo experimento visou avaliar a qualidade final e o período de conservação de mamões minimamente processados submetidos a 3 tipos de tratamentos químicos: CaCl2 (1%); ácido ascórbico (0,5%); a combinação de CaCl2 (1%) e ácido ascórbico (0,5%); e o controle (sem aplicação de tratamento químico), os quais foram acondicionados em embalagem de polietileno tereftalato rígida (PET) a 6&#176;C por um período de 9 dias. Os mamões tratados com CaCl2 (1%) e a combinação de CaCl2 (1%) e ácido ascórbico (0,5%) preservaram o teor de açúcares, coloração, textura e as caracteristicas sensoriais durante todo o período de armazenamento avaliado (9 dias), enquanto que os tratados com ácido ascórbico tiveram a textura prejudicada evidenciada pela maior solubilização da pectina, denotando maior amolecimento dos tecidos. Os resultados mostraram que a adição de ácido ascórbico não foi eficaz para a preservação da qualidade de mamões minimamente processados e prolongamento da sua vida útil. As contagens de bactérias psicrotróficas mantiveram-se dentro dos limites aceitáveis para todos o tratamentos aplicados. O terceiro experimento avaliou o efeito do uso de atmosfera modificada passiva e ativa na qualidade de mamões minimamente processados, tratados com a combinação de CaCl2 (1%) e ácido ascórbico (0,5%). Após o processamento, os mamões, previamente tratados, foram submetidos a três tipos de acondicionamento: bandejas de poliestireno rígida, recobertas com filme de polipropileno 32 &#956;m, sem e com injeção de gás (5% O2 + 10% CO2) e embalagem de polietileno tereftalato rígida (PET), com tampa, a qual foi utilizada como controle. Foram realizadas análises de O2 e CO2, físico-químicas, sensoriais e microbiológicas. Os mamões acondicionados em PET apresentaram pouca modificação gasosa porém mantiveram as características físico-químicas, sensoriais e microbiológicas, durante todo período de armazenamento avaliado (9 dias). Isto mostrou que a combinação de tratamento químico CaCl2 (1%) e ácido ascórbico (0,5%) foi eficaz e influenciou diretamente nos parâmetros avaliados. Os mamões minimamente processados acondicionados em filme de polipropileno com e sem injeção de gás, apresentaram comportamento semelhante para a maioria dos parâmetros físico-químicos e sensoriais (sabor e aparência), sendo que, a partir do 6&#176;dia de armazenamento, foi constatada coloração alaranjada mais intensa (escurecimento da polpa) a qual se refletiu diretamente na aparência do produto. O uso de atmosfera modificada ativa mostrou-se eficiente no retardamento da proliferação de microorganismos psicrotróficos. / This work had as objective to evaluate the physiologic, physiochemical, microbiological and sensorial alterations in in minimally processed papayas, submitted to chemical treatments and passive and active modified atmosphere. In the first experiment, the respiratory activity and ethylene production were analized in minimally processed papayas treated with CaCl2 (1%); ascorbic acid (0,5%); the combination of CaCl2 (1%) and ascorbic acid (0,5%); and control (without application of chemical treatment). The final product was stored at 6&#176;C (&#177;1&#176;C) and 90% (&#177;5%) of relative humidity for a period of 6 days. The results showed that processed papayas treated with chloride of calcium obtained a significantly smaller respiration activity from the 1st storage day, showing that CaCl2 (1%) may collaborate on the prolongation of the processed fruit shelf life. The second experiment had as objective to evaluate the final quality and the period of conservation of minimally processed papayas submitted to 3 types of chemical treatments: CaCl2 (1%); ascorbic acid (0,5%); the combination of CaCl2 (1%) and ascorbic acid (0,5%); and the control (without application of chemical treatment), which were conditioned in rigid polyethylene terephthalate (PET) packages at 6 C° for a period of 9 days. The papayas treated with CaCl2 (1%) and the combination of CaCl2 (1%) and ascorbic acid (0,5%) preserved some physiochemical characteristics like the sugar rate, texture and color and sensorial characteristics during the whole period of the appraised storage (9 days), while the treatements with ascorbic acid had the texture prejudiced, presenting softening in the tissue. The results showed that the addition of ascorbic acid was ineffective for the preservation of the minimally processed papayas quality and the prolongation of the shelf life. The countings of psychotrophic bacteria stayed inside of the acceptable limits for all the applied treatments. The third experiment had as objective to evaluate the effect of the passive and active modified atmosphere using in the minimally processed papayas quality, treated with the combination of CaCl2 (1%) and ascorbic acid (0,5%). After the processing, the papayas, previously treated, were submitted to three package types: rigid trays of polystyrene, covered with a polypropylene film 32 &#956;m, with and without injection of gas (5% O2 + 10% CO2) and packages of rigid polyethylene terephthalate (PET), with cover, which was used as control. Physical-chemical, sensorial, microbiological, O2 and CO2 analyses were accomplished. The papayas conditioned in PET presented little gaseous modification but maintained the physico-chemical, sensorial and microbiological characteristics, during all the periods of storage (9 days). The experiment showed that the combination of CaCl2 (1%) and ascorbic acid (0,5%) was effective and influenced the appraised parameters. The minimally processed papayas conditioned in polypropylene film with and without injection of gas, presented similar behavior for most of the physicalchemical and sensorial parameters (taste and appearance), and, starting from the 6 day of storage, more intense orange coloration was verified (bronwning of the pulp) which was reflected directly in the appearance of the product. The use of active modified atmosphere was shown efficient in the retardation of the psychotrophic organisms proliferation.
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Využití vedlejších energetických produktů a dalších druhotných surovin pro výrobu alfa sádry / Use of energetic by-products and other secondary raw materials for the alpha gypsum production

Moldrzyk, Jan January 2014 (has links)
Thesis focus on the longterm research in an area of alpha gypsum production by non pressure method in chloride salt solutions production, which is researched by Institute od technology of building materials and components, Faculty of civil engineering for many years. The result of given research is non pressure equipment for alpha gypsum production. The scope of this research was to make a production of alpha gypsum more efficient through modification of the facility itself and through an optimalization of dehydration process. The scientific aim of this process was to compare an influence of dehydratation solutions of CaCl2, NaCl and KCl on the final product provided that molarity of solutions was at the same level.
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Effect of De-icer and Anti-icer Chemicals on the Durability, Microstructure, and Properties of Cement-based Materials

Julio Betancourt, Gustavo Adolfo 24 September 2009 (has links)
A comprehensive study was conducted on the effects of de-icer and anti-icer chemicals on cement-based materials. Portland cement mortars and concretes were exposed to over 16 chloride-based and non-chloride-based generic and commercial products and changes in cement-based material properties were measured. Deleterious chemical actions of several types of these products on cement-based materials were observed, departing from the well-known position that attributes the concrete damage from such salts mainly to physical actions under freezing and thawing exposure. Independent of freezing and thawing exposure, mortars and concretes exposed to concentrated calcium chloride and magnesium chloride solutions were found to undergo severe deterioration whereas those exposed to sodium chloride did not. The mechanisms of deterioration are complex with factors such as concentration, temperature, and availability of calcium hydroxide playing important roles. It was found that the formation of calcium oxychloride of the form 3Ca(OH)2.CaCl2.12H2O, and the 3- and 5-form magnesium oxychloride, 3Mg(OH)2.MgCl2.8H2O and 5Mg(OH)2.MgCl2.8H2O, were the main causes for the severe deterioration, and to a lesser extent brucite, gypsum, and magnesium silicate hydrate (M-S-H). The instability of these oxychloride compounds when subjected to conditions normally encountered in sample preparation is suggested as the reason why field investigations have failed to relate distressed concrete to chemical attack by such de-icer and anti-icer chemicals. Concentrated solutions of calcium magnesium acetate were also found to be harmful to cement-based materials by dissolution of calcium hydroxide and formation of calcium acetate hydrate, whereas low concentrated solutions tended to cause slow deterioration by magnesium attack forming brucite, gypsum, and M-S-H. Potassium acetate chemicals did not cause significant deterioration in mortars when these products were diluted (25% by mass), but undiluted products (50% by mass) caused considerable distress in concrete specimens. The combined effect of chemical attack impairing concrete mechanical properties and subsequent salt scaling damage was proposed as the most likely mechanisms of field deterioration.

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