Made available in DSpace on 2015-04-17T14:49:20Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1039445 bytes, checksum: c9718b3d3af181ba84c4ac635660ce79 (MD5) Previous issue date: 2009-09-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed to evaluate the use of modified atmosphere (MA) in the conservation of sweet cassava variety 'Pernambuana' minimally processed in plastic containers. In the first stage determined the chemical composition (macro and micronutrients), heavy metals, the cooking time (DTC), quality of cooking and cyanogenic compounds. Minimal processing was the subdivision into two areas, dirty areas: reception of raw materials, selection, classification and pre-wash. In the second step, the clean area: processing (peeling and cutting), rinse, sanitizing, spinning, packing, storage. We analyzed the gas concentration (O2 and CO2) inside the package by 70 pm. The experiment was conducted at temperature 10 °C and stored in polystyrene containers terephthalate (PET) without PVC (CONT), PET with PVC (AMCF), sealed polyethylene bags without vacuum (AMSV) and vacuum (AMCV) at 5 ± 0.2 º C, RH 43% for 20 days. Were performed physical and chemical analysis. The increase in browning (IE), staining of cuttings (L *, C *, H *). and enzyme activity were performed every four days until the 16th day. The microbiological analysis of fecal and total coliforms were performed on the day of processing, with eight and sixteen days. The variety 'Pernambucana‟ has got cooking time of 20 minutes, quality mass formed after cooking and low levels of cyanogenic compounds. It was observed that the pH, ascorbic acid, varied significantly during storage. There were statistical differences (P ≤ 0.05) for the values of reducing sugars, total soluble sugars during periods of storage. Packaging (AMSV and AMCV) had the highest values of L *, the lowest increment of darkening, a smaller reduction of ascorbic acid, however, had the highest pH values. The enzymes showed no statistical differences (P ≤ 0.05) for the activity of peroxidase and polyphenol in storage periods and between treatments. Considering the physico-chemical and microbial life of cassava was 12 days for treatments AMSVand AMCV and eight days for the treatment AMCF. According to the microbiological analysis of cassava breeding minimally processed showed an absence of coliform bacteria at 45 °C, however, treatment with AMCF, and AMSV AMCV showed total coliform counts considered high. / Este trabalho teve como objetivo avaliar o uso de atmosfera modificada (AM) na conservação de mandioca de mesa da variedade Pernambucana‟ minimamente processada em embalagens plásticas. Na primeira etapa determinou-se a composição química, (macro e micronutrientes), metais pesados, o tempo de cocção (DTC), qualidade de massa cozida e compostos cianogênicos. O processamento mínimo consistiu na subdivisão em duas áreas, área suja: recepção da matéria-prima, seleção, classificação e pré-lavagem. Na segunda etapa, na área limpa: processamento (descascamento e corte), enxague, sanificação, centrifugação, embalagem, armazenamento. Analisou-se a concentração gasosa (O2 e CO2) no interior das embalagens, por 70 hs. O experimento foi realizado em câmara fria a 10ºC e armazenados nas embalagens Poliestireno tereftalato (PET) sem PVC (CONT), PET com PVC (AMCF), saco de polietileno selado sem vácuo (AMSV) e com vácuo (AMCV) à temperatura de 5 ± 0,2ºC, UR 43% por 20 dias. Foram realizadas as análises físico-químicas. O incremento de escurecimento (IE), coloração dos toletes (L*, C*, H*). e atividade enzimática foram realizadas a cada quatro dias até o 16º dia. As análises microbiológicas de coliformes totais e termotolerantes foram realizadas no dia do processamento, com oito e dezesseis dias. A variedade Pernambucana apresenta obteve tempo de cozimento de 20 minutos, qualidade massa formada após cozimento e baixo teores de compostos cianogênicos. Observou-se que os valores de pH, ácido ascórbico, variaram significativamente durante o armazenamento. Houve diferenças estatísticas (P≤0,05) para os valores de açúcares redutores, açúcares solúveis totais nos períodos de armazenamento. As embalagens (AMSV e AMCV) obtiveram os maiores valores de L*, os menores valores de incremento de escurecimento, menor redução de ácido ascórbico, no entanto, obteve os maiores valores de pH. As enzimas apresentaram diferenças estatísticas (P≤0,05) para a atividade da polifenol e peroxidase nos períodos de armazenamento e entre os tratamentos. Considerando-se a análise físico-química e microbiológica, a vida útil da mandioca foi de 12 dias para os tratamentos AMSV e AMCV e oito dias para o tratamento AMCF. De acordo com as análises microbiológicas a mandioca de mesa minimamente processada apresentou ausência de coliforme a 45ºC, no entanto, os tratamentos com AMCF, AMSV e AMCV apresentaram contagem de coliformes totais consideradas altas. Palavras-

Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-13Bitstream added on 2014-06-13T21:06:45Z : No. of bitstreams: 1 hojo_etd_dr_jabo.pdf: 1539570 bytes, checksum: 9a8c4375124457a8e811faf5f3693cc6 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Visando prolongar a vida útil da lichia, principalmente quanto à manutenção da cor e da qualidade, executaram-se experimentos para avaliar a eficiência dos tratamentos hidrotérmico e com solução de ácido clorídrico (HCl); do armazenamento sob refrigeração, em atmosfera controlada e em diferentes embalagens plásticas e de coberturas com quitosana. No Experimento I, testou-se a imersão em HCl a 0,087M por 6 minutos; o tratamento hidrotérmico por imersão a 52ºC por 1 minuto, seguido de resfriamento em água a 10ºC por 6 minutos; e o tratamento hidrotérmico com resfriamento em HCl a 0,087M a 10ºC por 6 minutos. O tratamento hidrotérmico seguido de resfriamento em HCl conservou a coloração dos frutos até o 3º dia, e a polpa com qualidade adequada até o 12º dia. No Experimento II, utilizou-se o melhor tratamento do experimento anterior (hidrotérmico com resfriamento em HCl) e testaramse diferentes temperaturas de armazenamento: 2ºC (91% UR); 5ºC (98% UR); 10ºC (80% UR); e 20ºC (70% UR). Os frutos foram analisados após 1, 4, 7, 10, 13, 16, 19, 22 e 25 dias. O armazenamento de lichia a 5 ºC manteve a boa aparência por até 13 dias e a qualidade da polpa até o final do período, 25 dias. O armazenamento a 2 ºC levou a maiores prejuízos na aparência. As temperaturas, de 10 ºC e 20 ºC, não foram efetivas para a manutenção da cor vermelha da casca. No Experimento III, foi testado o efeito da atmosfera controlada, associado aos melhores tratamentos dos experimentos anteriores. Os frutos foram armazenados a 5ºC e 94% UR, em atmosfera controlada contendo 5%, 10%, 20% e 80% de O2, com avaliações após 0 (inicial), 3, 7, 14, 21, 28 dias. As lichias de todos os tratamentos mantiveram a boa qualidade da polpa por até 21 dias, com os frutos sob atmosfera com 5% de O2, apresentando menor escurecimento da casca. As lichias apresentaram escurecimento da casca... / Aiming to extend litchi life, especially regarding to color and quality maintenance, experiments were performed to evaluate the treatment efficiency under heat and using hydrochloric acid solution (HCl), refrigerated storage, controlled atmosphere, different plastic containers, and chitosan coatings. In Experiment I, it was tested immersion in 0,087M HCl for 6 minutes; hydrothermal treatment by immersion at 52ºC for 1 minute, followed by water cooling at 10ºC for 6 minutes; and hydrothermal treatment with 0,087M HCl cooling at 10 ºC for 6 minutes. Hydrothermal treatment followed by HCl cooling preserved fruit color until the 3rd day and adequate pulp quality until the 12th day. In Experiment II, it was used the best treatment in the previous experiment (hydrothermal with HCl cooling) and different storage temperatures were tested: 2ºC (91% RH), 5ºC (98% RH), 10ºC (80% RH), and 20ºC (70% RH). Fruits were analyzed after 1, 4, 7, 10, 13, 16, 19, 22, and 25 days. Storage at 5ºC kept the good fruit appearance for up to 13 days, and pulp quality until the 25th day. The 2ºC led to to ligher losses in appearance. The temperatures of 10ºC and 20ºC, were not effective for maintaining the red color of the skin. In Experiment III, the effects of controlled atmosphere combined with improved treatments of previous experiments were tested. Fruits were stored at 5ºC and 94% RH in a controlled atmosphere containing 5%, 10%, 20% and 80% O2, with evaluations after 0 (initial), 3, 7, 14, 21, 28 days. Litchis in all treatments maintained good pulp quality for up to 21 days, with the fruits under a 5% O2 atmosphere showing a lower skin browning. Litchis showed over 50% skin browning after 7 days. In Experiment IV, different concentrations of CO2 (0%, 5%, 10%, 15%, and 20%) combined with the best concentration in the previous experiment, 5% O2, were tested... (Complete abstract click electronic access below)

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of the present work was to evaluate the efficiency of pre-harvest application of fungicides on control of brown rot on postharvest and verify their effect when associated with fungal antagonists, ensuring efficiency in the control of disease and quality of fruit. We evaluated the effect of application of fungicides on pre-harvest in the control of brown rot after 15 and 40 days of refrigerated storage of fruits, in addition to the association of fungicides with postharvest treatment with the fungus antagonist, Trichoderma harzianum. To do this, were established two experiments. At the first, phytosanitary programs (active ingredients) were evaluated: [1] control (application of water); [2] captan; [3] iprodione; [4] iminoctadine; [5] tebuconazole; [6] procymidone; [7] azoxystrobin; [8] difenoconazole; [9] fungicide (azoxystrobin/difenoconazole); [10] fungicide (trifloxystrobin/tebuconazole); [11] sequence iminoctadine + captana; [12] sequence of iprodione + iminoctadina; [13] sequence of tebuconazole + captan; [14] sequence of tebuconazole + iprodione. All treatments were applied in the pre-harvest phase, in recommended doses for culture. After harvesting the fruits were stored at -0.5 °C for 15 and 40 days. In the second experiment were evaluated the pre-harvest application of following products: [1] control (application of water); [2] captan; [3] iprodione; [4] iminoctadine; [5] tebuconazole. After harvesting the fruits were stored at -0.5 °C for 40 days and following, in half of the fruits of each treatment was applied the antagonist Trichoderma harzianum, through immersion. Both experiments were evaluated after exposure of fruit to 20 °C for a period that varied from four to 12 days, depending on the storage time of each experiment. The parameters evaluated were: incidence of brown rot, percentage of healthy fruits, respiratory rate, ethylene production and skin browning. Until the time of harvesting the fungicide which best controlled the brown rot was the difenoconazole, whereas, the fungicides tebuconazole and iminoctadina have satisfactory results in control of brown rot, after 15 and 40 days of refrigerated storage. The use of Trichoderma harzianum has no effect on postharvest control of brown rot, however, when associated with fungicides is effective in the control of Rhizopus stolonifer. Pre-harvest application of fungicide captan and postharvest of Trichoderma harzianum affect postharvest quality of fruits, causing skin browning. / O objetivo do presente trabalho foi avaliar a eficiência da aplicação pré-colheita de fungicidas no controle da podridão parda em pós-colheita e verificar o seu efeito quando associado a fungos antagonistas, assegurando eficiência no controle da doença e qualidade dos frutos. Para tanto, avaliou-se o efeito da aplicação de fungicidas em pré-colheita no controle da podridão parda do pessegueiro após 15 e 40 dias de armazenamento refrigerado dos frutos, além da associação de fungicidas com o tratamento pós-colheita com o fungo antagonista, Trichoderma harzianum. Para isso, foram instalados dois experimentos. No primeiro foram avaliados programas fitossanitários com os seguintes produtos (ingredientes ativos): [1] testemunha (aplicação de água); [2] captana; [3] iprodiona; [4] iminoctadina; [5] tebuconazol; [6] procimidona; [7] azoxistrobina; [8] difenoconazol; [9] fungicida (azoxistrobina/difenoconazol); [10] fungicida (trifloxistrobina/tebuconazol); [11] sequência de iminoctadina + captana; [12] sequência de iminoctadina + iprodiona; [13] sequência de tebuconazol + captana; [14] sequência de tebuconazol + iprodiona. Todos os tratamentos foram aplicados na fase pré-colheita, nas doses recomendadas para a cultura. Após a colheita os frutos foram armazenados a -0,5 ºC por 15 e 40 dias. O segundo experimento constituiu-se da aplicação pré-colheita dos seguintes produtos: [1] testemunha (aplicação de água); [2] captana; [3] iprodiona; [4] iminoctadina; [5] tebuconazol. Após a colheita os frutos foram armazenados a -0,5 ºC por 40 dias e na sequência, na metade dos frutos de cada tratamento foi aplicado o fungo antagonista Trichoderma harzianum, por meio de imersão. Ambos os experimento foram avaliados após a exposição dos frutos à temperatura de 20 ºC, por um período que variou de quatro a 12 dias, dependendo do tempo de armazenamento de cada experimento. Os parâmetros avaliados foram: incidência de podridão parda, porcentagem de frutos sadios, taxa respiratória, produção de etileno e escurecimento da epiderme. Até o momento da colheita, o fungicida que melhor controlou a podridão parda foi o difenoconazol, enquanto que, os fungicidas iminoctadina e tebuconazol apresentam resultados satisfatórios no controle da podridão parda, após 15 e 40 dias de armazenamento refrigerado. A utilização do Trichoderma harzianum em pós-colheita não apresenta efeito no controle da podridão parda do pessegueiro, entretanto, quando associado a fungicidas é eficiente no controle de Rhizopus stolonifer. A aplicação pré-colheita do fungicida captana e a utilização pós-colheita de Trichoderma harzianum afetam a qualidade pós-colheita dos frutos, causando escurecimento da epiderme.

Orientador: Miriam Dupas Hubinger / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T06:04:01Z (GMT). No. of bitstreams: 1 Bierhals_VaniadaSilva_M.pdf: 6398084 bytes, checksum: 029e237ca3d107d4de42a993f603c6dd (MD5) Previous issue date: 2010 / Resumo: A produção de frutas minimamente processadas representa uma alternativa para a redução das perdas pós-colheita e uma maneira de agregar valor ao produto, atendendo a atual demanda do mercado por alimentos prontos para o consumo com qualidade, frescor e conveniência. O abacaxi destaca-se, em função de sua excelente qualidade sensorial e de certa dificuldade para consumo imediato. Entretanto, sua vida útil é limitada pelas mudanças indesejáveis de cor, textura, sabor, aroma e crescimento microbiológico. Assim, o objetivo do presente trabalho foi estudar o efeito da aplicação das coberturas comestíveis a base de fécula de mandioca ou alginato de sódio na vida útil de abacaxis minimamente processados em rodelas, pré-tratadas com ácido ascórbico (1%) e cítrico (0,5%), adicionadas ou não de lactato de cálcio (2%), e armazenados a 5 °C. Amostras tratadas somente com os agentes inibidores de escurecimento foram usadas como controle. Concentrações de 1% a 3% de fécula de mandioca e 1% e 2% de alginato de sódio foram testadas previamente. A aplicação das coberturas não alterou significativamente as propriedades mecânicas (força máxima de penetração e tensão e deformação na ruptura) e a cor (L*, C* e H*) das rodelas de abacaxi. Todos os tratamentos foram bem avaliados sensorialmente, apresentando notas acima de 6,5. Os tratamentos com 2% de fécula de mandioca e 2% de alginato de sódio reduziram significativamente a perda de peso e a taxa respiratória e aumentaram a resistência à difusão de água quando comparadas à amostra controle. Com base nestes resultados, foram selecionadas para o estudo da vida útil coberturas com 2% de fécula ou alginato, utilizando ou não lactato de cálcio. Neste estudo verificou-se que ao longo de 12 dias de armazenamento a 5° C, as coberturas foram eficientes em reduzir a perda de peso, o suco drenado na embalagem e mantiveram as propriedades mecânicas das frutas. Entretanto, as amostras apresentaram maior escurecimento da fruta e redução mais acentuada no teor de ácido ascórbico durante o estudo da vida útil. Todos os tratamentos foram bem avaliados sensorialmente, apresentando notas acima de 6, com exceção das amostras com cobertura de alginato e pré-tratadas com cálcio, que apresentaram notas próximas ao limite de aceitabilidade (4,5). O fator determinante da vida útil das rodelas de abacaxi foi a contaminação fúngica em todos os tratamentos, sendo que ela foi maior nas amostras revestidas com as coberturas de fécula de mandioca ou alginato de sódio, que apresentaram vida útil de 7 e 8 dias, respectivamente. Já as rodelas de abacaxi tratadas somente com agentes inibidores de escurecimento obtiveram, em média, vida útil de 10 dias, indicando que apenas o pré-tratamento com sanitizante e solução de ácido ascórbico e cítrico permitiu um prolongamento da vida útil de abacaxis minimamente processados / Abstract: The production of minimally processed fruits represents an alternative to the reduction of postharvest losses and a way to add value to the product, considering the current market demand for ready-to-eat food with quality, freshness and convenience. The pineapple is appreciated due to its sensorial characteristics and some difficulty for immediate consumption. However, its shelf life is limited by changes in color, texture, taste, off-flavors and microbial growth. The aim of this work was to study the effect of application of edible coatings of cassava starch or sodium alginate in the shelf life of minimally processed pineapple in slices, pretreated with ascorbic (1%) and citric acid (0.5%), with or without added calcium lactate (2%), and stored at 5 °C. The samples treated on ly with anti-browning agents were used as control. Coatings with cassava starch concentrations between 1% to 3% and sodium alginate from 1% and 2% were previously tested. The coating application did not affect mechanical properties (maximum mechanical penetration, stress and strain at failure) and color (L*, C* and H*) of pineapple slices and all treatments received good scores on the sensory analyses (all scores above 6.5). The treatments with 2% cassava starch and 2% sodium alginate significantly reduced the weight loss and respiration rate and increased water vapor resistance, when compared to control samples. Considering these results the conditions selected for shelf life studies were: coating concentrations with 2% of starch or alginate, using or not calcium lactate. Edible coatings were efficient in reducing weight loss, juice leakage and mechanical properties maintenance. However, the coated samples showed more browning and ascorbic acid content was reduced throughout the shelf life study. All treatments presented good sensory acceptance (scores above 6), except for alginate coating pre-treated with calcium, which presented scores close to the limit of acceptability (4.5). The determining factor of shelf life of pineapple slices was the microbial spoilage. The samples coated with cassava starch and sodium alginate coatings showed a reduced shelf life of 7 and 8 days, respectively and higher yeast and mould growth. A shelf life of 10 days was obtained for pineapple slices treated only with anti-browning agents, indicating that the treatment with sanitizing agent and ascorbic and citric acid solution was efficient in increasing the shelf life of minimally processed pineapple / Mestrado / Mestre em Engenharia de Alimentos

Le séchage est un procédé de transformation largement répandu dans le monde qui permet d'augmenter significativement la durée de conservation des denrées alimentaires et d'apporter une valeur ajoutée aux produits. Le traitement thermique appliqué lors de cette opération peut causer des modifications physiques, chimiques et biochimiques aboutissant à des altérations des qualités nutritionnelles et organoleptiques des produits séchés. La couleur est le premier attribut perçu par le consommateur et est généralement corrélé à une représentation de la qualité globale du produit. La maîtrise du brunissement est donc capitale pour préserver le potentiel commercial des produits alimentaires. La filière mangue séchée biologique du Burkina Faso constitue le cadre d'étude de ces travaux de thèse axés sur la compréhension des phénomènes impliqués dans le brunissement des mangues au cours de l'opération de séchage et pendant le stockage. L'objectif principal est d'identifier les paramètres majeurs influant sur le brunissement enzymatique et non-enzymatique afin de proposer des voies d'amélioration de la qualité du produit pertinentes. Une approche expérimentale permettant d'étudier les effets spécifiques de la température et de l'activité de l'eau indépendamment des autres paramètres nous a permis d'identifier les points critiques du procédé induisant des altérations de la couleur. / Drying is a world common transformation process which significantly increase the food shelf-life and the added value of the products. The heat treatment applied during this operation can provoke physical, chemical and biochemical modifications resulting to alterations in nutritional and organoleptic properties of dried products. Color is the first property perceived by the consumer and is generally correlated with a global representation of product quality. Browning knowledge is essential to conserve the commercial potential of food. Dried mango sector in Burkina Faso constitute a part of my course thesis based on the understanding of phenomena involved in the mango browning during drying process and then during the storage. The global objective is to identify the main parameters affecting the enzymatic and non-enzymatic browning in order to propose optimized technological ways improving the final quality of the dried mango products. Experimental approach offering possibility to study temperature and water activity specifics effects independently to other parameters allowed us to identify critical points of the process occurring color variations.

Thesis (MSc. (Horticulture)) -- University of Limpopo, 2019 / After harvesting litchi fruit, the red pericarp colour is rapidly lost resulting in discolouration and browning during storage and marketing. To mitigate this challenge, the South African litchi industry uses sulfur dioxide fumigation to retain litchi fruit red pericarp colour during extended storage and shelf-life. However, there are health concerns regarding the commercially used (SO2) fumigation for litchi pericarp colour retention due to high levels of SO2 residues in fruit aril. Therefore, this study aimed to explore the possibility of Uvasys slow release SO2 sheets to retain ‘Mauritius’ litchi fruit red pericarp colour when packaged in plastic-punnets and bags. Treatment factors were two packaging materials (plastic-punnets and bags), six SO2 treatments (control; SO2 fumigation and four SO2 sheets viz. Uva-Uno-29% Na2S2O5; Dual-Release-Blue35.85% Na2S2O5; Slow-Release-36.5% Na2S2O5 and Dual-Release-Green-37.55% Na2S2O5) and four shelf-life periods (day 0, 1, 3 and 5). ‘Mauritius’ fruit were assessed for pericarp Browning Index (BI), Hue angle (ho), Chroma (C*) and Lightness (L*). In this study, an interactive significant effect (P < 0.05) between packaging type and SO2 treatments was observed on ‘Mauritius’ fruit pericarp L*, C* and ho during shelf-life. Fruit stored in plastic-bags and treated with SO2 fumigation showed higher pericarp C* and L*, while SO2 fumigated fruit in plastic-punnets had higher pericarp ho. Lower pericarp BI was observed in SO2 fumigated fruit stored in plastic-bags, which showed less pericarp browning than fruit in other treatments. In general, commercial SO2 fumigation resulted in lower pericarp BI, and higher pericarp L*, C* and ho throughout the storage and shelf-life. Our correlation analyses results further showed that litchi fruit red pericarp colour was better preserved as SO2 treatment levels increased, especially in plastic-bags. In retaining ‘Mauritius’ litchi fruit red pericarp colour, Uvasys SO2 sheets were not effective when compared with commercial SO2 fumigation. However, commercially SO2 fumigated fruit were bleached throughout the storage and shelf-life. Furthermore, fruit from all treatments were spoiled due to decay and mould growth after day 5 of shelf-life. Inclusion of pathogen protectants is important in future research to demonstrate whether Uvasys SO2 sheet-packaging technology can retain ‘Mauritius’ litchi fruit pericarp colour. / Agricultural Research Council and National Research Foundation (NRF)

<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Nastajanje i inhibicija stvaranja melanoidina u nečistim rastvorima saharoze je ispitivana na uzorcima neafinisanog i afinisanog C produkta na 80 [&deg;C].</p><p>Utvrdjena je zavisnost obrazovanja bojenih materija tipa melanoidina od vremena reakcije, od sadržaja suve materije, kao i od sadržaja i vrste aminokiselina.<br />Smanjenje obojenosti rastvora zavisi od koncentracije natrikum-sulfita i matematički je definisano Baule-Mitscherlichovim krivama zasićenja. Maksimalni efekat odbojavanja koji se može postići iznosi 30 [%] na 560 [nm], odn. 20 [%] na 420 [nm], ne razlikuje se za rastvore neafinisanog i afinisanog C produkta, a ostaje nepromenjen u vremenu od 1620 [min].</p><p>Povećanje koncentracike vodonik-peroksida je praćeno porastom količine bojenih materija prevedenih u leuko oblike, i produžavanjem vremena oksidacije. U odsustvu slobodnog vodonik-peroksida dolazi do reverzije boje rastvora.<br />Smanjenje obojenosti rastvora neafinisanog i afinisanog C produkta je signifikantno veće pri uzastopnom delovanju oksidacionog i redukcionog sredstva od smanjenja obojenosti postignutog njihovim pojedinačnim delovanjem. Efekti uzajamnog delovanja se ne menjaju u ispitivanom vremenu.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>Reaction and inhibition of melanoidine formation in inpure solutions of sucrose were investigated on affinated and unaffinated C sugar samples carried out on 80 [&deg;C].<br />Melanoidin type colour formation dependending on reaction time, dry matter content and content and variety on amino acids has been studied.<br />Colour decrease in solutions depended on concentration of sodium sulphite and was mathematically defined by Baule-Mitscherlich curve of saturation. Maximum effect of colour decrease wich can be obtained was 30 [%] at 560 [nm], and 20 [%] at 420 [nm] wavelength respectively, and without any difference between affinated and unaffinated C sugar solutions, but it has stayed unchanged during reaction time of 1620 [min]. Hydrogen peroxide concentration rise was followed by increasing amounts of colour compounds transferred in leuco forms and by prolonged oxidation time. Absence of free hydrogen peroxide has induced the reverse formation of colour solutions.</p><p>Colour decrease in unaffinated and affinated C sugar solution was significantly larger, during subsequent treatment of oxidizing and reducing compounds, than during separate reactions. During reaction time the mutual treatment effect was unchangeable.</p>

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