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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.
51

Probiotics, prebiotics and synbiotics use in neonates : a critical appraisal of the evidence and evaluation of its application by the food industry

Mugambi, Mary Letizia Nkatha 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Background: Synbiotics, probiotics and prebiotics are being added to infant formula. This study was an in-depth evaluation of research on infants fed infant formula containing synbiotics, probiotics or prebiotics and was carried out in two phases. Phase one included two systematic reviews that assessed if synbiotics, probiotics or prebiotics led to improved growth and clinical outcomes in formula fed full term and preterm infants. Phase two included two studies: A systematic review compared the methodological quality and outcomes of industry and non-industry sponsored randomized controlled trials (RCTs) and a descriptive study evaluated how the food industry applies the knowledge and evidence gained from probiotics, prebiotics or synbiotics research in infants. The research questions were: Does the consumption of probiotics, prebiotics or synbiotics supplemented infant formula lead to improved clinical outcomes in infants? Is there an association between source of funding and methodological quality, clinical outcomes and author’s conclusions in trials using probiotics, prebiotics or synbiotics supplemented formula in infants? Does the food industry use the evidence gained through probiotics, prebiotics and synbiotics research trials on infants for the benefit of the general paediatric population? The hypotheses were: Consumption of probiotics, prebiotics or synbiotics by infants leads to improved clinical outcomes; The source of funding in research trials using probiotics, prebiotics or synbiotics supplemented formula in infants is associated with outcomes in favour of the sponsor’s products and authors’ conclusions; Methodological qualities of non-industry sponsored trials are equivalent to industry sponsored trials; Evidence gathered through probiotics, prebiotics and synbiotics research is implemented by the food industry. Methods: Phase one: Both systematic reviews on preterm and full term infants: Cochrane methodology was followed using RCTs which compared preterm or full term formula containing probiotics, prebiotics or synbiotics to conventional infant formula with / without placebo among healthy preterm or full term infants. The mean difference (MD) and corresponding 95% confidence intervals (CI) were reported for continuous outcomes, risk ratio (RR) and corresponding 95% CI for dichotomous outcomes. Phase two: In the systematic review, Cochrane methodology was used to assess the risk of bias of included RCTs. Association between source of funding and risk of bias, clinical outcomes and conclusions were assessed. In the descriptive study, all listed companies that manufacture infant food products with added synbiotics, probiotics or prebiotics for infants were identified and invited to participate. A letter of invitation was sent and if they expressed willingness to take part in the study, a questionnaire with a written consent form was sent. Descriptive statistics and associations between categorical variables were to be tested using a Chi-square test. Results: Phase one: Review on preterm infants: 8 studies were included. Probiotics increased stool frequency with no effect on other clinical outcomes. Prebiotics increased stool frequency and bifidobacteria counts only. Review on full term infants: 25 studies were included. Synbiotics improved stool frequency but had no effect on other clinical outcomes. Probiotics did not have an effect on any clinical outcome. Prebiotics increased weight gain and stool frequency with no effect on other outcomes. Phase two: Systematic review: 67 studies were included, majority were funded by food industry. There was no significant association between the source of funding and four domains (sequence generation, allocation concealment, blinding, selective reporting), majority of reported clinical outcomes or authors’ conclusions. Source of funding was significantly associated with two domains (incomplete outcome data, free of other bias), antibiotic use and conclusions on weight gain. Descriptive study: 25 companies were identified and invited to participate. No company agreed to participate in the survey for different reasons. Conclusions Phase one: Review on preterm infants: There is not enough evidence to state that supplementation with probiotics or prebiotics results in improved growth and clinical outcomes in exclusively formula fed preterm infants. Review on full term infants: There is not enough evidence to state that supplementation of term infant formula with synbiotics, probiotics or prebiotics does result in improved growth or clinical outcomes in term infants. There is no data available to establish if synbiotics are superior to probiotics or prebiotics. Phase two: Systematic review: In RCTs on infants fed infant formula containing probiotics, prebiotics or synbiotics, the source of funding does not influence majority of outcomes in favour of the sponsors’ products. More non-industry funded research is needed to further assess the impact of funding on reported clinical outcomes and authors’ conclusions. Descriptive study: Due to companies refusing to participate in this study, no conclusion could be drawn on how the food industry applies evidence gained through probiotics, prebiotics or synbiotics research on infants. More transparency is needed from the infant formula manufactures on how they apply the evidence gained from probiotic, prebiotic or synbiotic research on infants. / AFRIKAANSE OPSOMMING: Agtergrond Synbiotika, probiotika en prebiotika word gereeld by baba formule gevoeg. Hierdie studie was 'n in-diepte evaluering van navorsing oor babas gevoed met formule melk wat synbiotika, probiotika of prebiotika bevat en is uitgevoer in twee fases. Fase een het twee sistematiese oorsigte ingesluit wat die rol van synbiotika, probiotika en prebiotika op verbeterde groei en kliniese uitkomste van formule gevoede volterm babas en vroeg gebore babas evalueer het. Fase twee het bestaan uit twee studies: 'n sistematiese oorsig wat die metodologiese kwaliteit en uitkomste van die bedryf en nie-bedryf geborgde ewekansige gekontroleerde proewe (RCTs) evalueer het, asook 'n beskrywende studie wat die kennis en toepassing van bewyse oor die effektiewiteit van probiotika, prebiotika of synbiotika in die voedsel industrie bestudeer het. Die hipotese stellings was: verbruik van probiotika, prebiotika of synbiotika by babas lei tot verbeterde kliniese uitkomste; die bron van befondsing vir synbiotics, probiotika of prebiotika navorsing beïnvloed uitkomste ten gunste van die borg se produkte; bewyse ingesamel deur middel van probiotika, prebiotika en synbiotika navorsing word geïmplementeer deur die voedselindustrie. Metodes Fase een: Beide sistematiese oorsigte op volterm en premature babas: Cochrane metodes is gevolg deur ewekansige, gekontroleerde studies wat vol termyn of premature formule met probiotika, prebiotika of synbiotika met konvensionele baba formule met / sonder plasebo onder gesonde volterm of premature babas bestudeer. Die gemiddelde verskil (MD) en die ooreenstemmende 95% vertrouensintervalle is gebruik vir deurlopende uitkomste, risiko verhouding (RR) en die ooreenstemmende 95% CI vir tweeledige uitkomste. Fase twee: In die sistematiese oorsig is Cochrane metodiek gebruik om die risiko van vooroordeel van ingesluite ewekansige, gekontroleerde studies te evalueer. Assosiasie tussen bron van befondsing en die risiko van vooroordeel, asook kliniese uitkomste en gevolgtrekkings was beoordeel. In die beskrywende studie, is alle genoteerde maatskappye wat babavoeding produkte vervaardig met bygevoegde synbiotika, probiotika of prebiotika vir babas geïdentifiseer en uitgenooi om deel te neem. 'n Uitnodigingsbrief is vir die relevante maatskappye gestuur om hul bereidwilligheid om deel te neem te bevestig. Indien hulle wel bereid was om deel te neem was 'n vraelys met 'n skriftelike toestemming vorm gestuur. Beskrywende statistiek en assosiasies tussen kategoriese veranderlikes was getoets met behulp van 'n Chi-kwadraat toets. Resultate Fase een: Oorsig oor premature babas: 8 studies was ingesluit. Probiotika verhoog stoelgang frekwensie met geen effek op ander kliniese uitkomste. Prebiotika verhoog ook stoelgang frekwensie en slegs bifidobakteriële tellings. Oorsig oor die vol termyn babas: 25 studies was ingesluit. Synbiotika verbeter stoelgang frekwensie, maar het geen effek op ander kliniese uitkomste gehad nie. Probiotika het nie 'n effek op enige kliniese uitkoms gehad nie. Prebiotika verhoog gewigstoename en stoelgang frekwensie met geen effek op ander uitkomste. Fase twee: Sistematiese oorsig: 67 studies was ingesluit, en die meerderheid was befonds deur die voedsel bedryf. Daar was geen beduidende assosiasie tussen die bron van befondsing en vier gebiede (toekenningsvolgorde, toekenningsverberging, studie verblinding, selektiewe verslaggewing), en die meerderheid van gerapporteerde kliniese uitkomste of skrywers se gevolgtrekkings. Die bron van befondsing was beduidend verbind met twee gebiede (onvolledige uitslag data, vry van ander vooroordeel), antibiotika gebruik en gevolgtrekkings op gewigstoename. Beskrywende studie: 25 maatskappye is geïdentifiseer en genooi om deel te neem. Geen maatskappy het ingestem om deel te neem aan die studie om verskillende redes. Gevolgtrekkings Fase een: Oorsig oor premature babas: Daar is nie genoeg bewyse dat die aanvulling met probiotika of prebiotika resultate in verbeterde groei en kliniese uitkomste in uitsluitlik formule gevoede premature babas tot gevolg het nie. Oorsig oor die volle termyn babas: Daar is nie genoeg bewyse om te sê dat die aanvulling van term baba formule met synbiotika, probiotika of prebiotika lei tot verbeterde groei of kliniese uitkomste in termyn babas. Daar is geen inligting beskikbaar om te stel of synbiotika beter is as probiotika of prebiotika nie. Fase twee: Sistematiese oorsig: In studies op babas gevoed met formule melk wat probiotika, prebiotika of synbiotika bevat het, het die bron van befondsing nie meerderheid van die uitkomste in die guns van die borge se produkte beïnvloed nie. Meer nie-industrie befondsde navorsing is nodig om verder die impak van befondsing op kliniese uitkomste en skrywers se gevolgtrekkings te evalueer. Beskrywende studie: Aangesien al die maatskappy deelname geweier het, kon geen gevolgtrekking gemaak word of die voedsel bedryf bewyse oor die gebruik van probiotika, prebiotika of synbiotika toepas nie. Meer deursigtigheid is nodig van die formule vervaardigers oor hoe hulle die bewyse oor die gebruik van probiotika, prebiotika of synbiotika toepas.
52

Desenvolvimento, avaliação e aplicação de micropartículas simbióticas produzidas por spray chilling / Development, evaluation and application of symbiotic microparticles produced by spray chilling technology

Okuro, Paula Kiyomi 12 July 2013 (has links)
Foram produzidas micropartículas simbióticas com carreador de natureza lipídica, obtidas por spray chilling. Como materiais ativos foram utilizadas duas cepas de micro-organismos probióticos (L. acidophilus-LA e L. rhamnosus-LR), dois prebióticos (inulina e polidextrose) e gordura de palma e palmiste interesterificada. Estudou-se a resistência destes probióticos ao processo aplicado, o comportamento das micropartículas sólido lipídicas (MSLs) frente ao fluido gástrico e intestinal simulados e suas viabilidades durante 120 dias de armazenamento à -18, 7 e 22°C sob vácuo ou umidade relativa controlada. A caracterização morfológica, granulometria, análise térmica (DSC), atividade de água, espectroscopia na região do infravermelho (FTIR) e difração de raios-X (XRPD) foram estudados. Spray chilling configurou-se como processo adequado aos probióticos, devido à baixa perda de células viáveis durante a obtenção das micropartículas, sendo que não foi observado interferência da ausência, presença e do tipo de prebiótico. Foram obtidas MSLs esféricas com superfície relativamente uniforme, e com tamanho médio entre 62,4±2,8 a 69,6±5,1 µm, sendo que não houve diferença significativa entre as formulações. As análises de difração de raios-X indicaram que não ocorreram alterações polimórficas durante o armazenamento refrigerado das MSLs. Quanto à análise térmica pode-se dizer que a presença de probióticos e prebióticos praticamente não interferiu na alteração da temperatura de fusão para todas as formulações estudadas, que variou de 45,37°C a 47,58°C, inferindo-se a ausência de interações significativas entre os ingredientes microencapsulados e o carreador, ausência que foi reafirmada pelos espectros de infravermelho. A microencapsulação favoreceu a sobrevivência frente aos fluidos gástrico e intestinal simulados, e possibilitou a manutenção de células viáveis acima de 106 UFC por grama até 120 dias de armazenamento em umidade relativa controlada para a formulação com L. acidophilus e polidextrose, a qual foi influenciada pela atividade de água da partícula, que por sua vez foi afetada pela incorporação de prebióticos. Tendo em vista o potencial da MSLs desenvolvidas, estas foram incorporadas ao sorvete. Nesta matriz as micropartículas não apresentaram um bom desempenho, seja na sobrevivência de L. acidophilus durante o armazenamento do produto, como na proteção diante da exposição às condições gastrointestinais simuladas. Além disso, sorvetes com adição das MSLs foram avaliados com notas significativamente menores (p≤0,05) nos atributos textura, sabor e aceitação global em relação a amostras controle e a com adição de probióticos livres na análise sensorial do produto desenvolvido. As micropartículas lipídicas produzidas mostraram-se aptas como ingrediente alimentício, porém no sorvete não atenderam as premissas de proteção e extensão de contagens apropriadas do probiótico. As MSLs também foram incorporadas em polpas de fruta, abacate e melão, neste tipo de matriz as MSLs conferiram proteção ao micro-organismo pois aumentaram sua viabilidade em relação aos micro-organismos livres. / Symbiotic microparticles were produced with a lipid carrier, obtained by spray chilling technology. In this study were used two strains of probiotic (L. acidophilus-LA and L. rhamnosus-LR) and two prebiotics (inulin and polydextrose) as active or core materials. The resistance of these probiotics to the spray chilling process was evaluated, as well as the viability of the solid lipid microparticles (SLMs) during the exposition to the simulated gastric and intestinal fluids and stability during 120 days of storage at -18, 7 and 22°C, in vacuum or controlled relative humidity. Morphology characterization, particle size, water activity, thermal analysis (DSC), infrared spectroscopy and X-ray diffraction (XRPD) were studied. Spray chilling process was configured as a suitable technology to probiotics due to low loss of viable cells in processing of the particle, and no interference was observed from the presence/absence and type of prebiotic component. MSLs were obtained with relatively uniform spherical surface, and average size between 62.4 ± 2.8 µm to 69.6 ± 5.1 µm, there was no significant difference between formulations. Analyses of X-ray diffraction indicated that there were no polymorphic changes during refrigerated storage of SLMs. As for the thermal analysis it can be said that the presence of probiotics and prebiotics had practically no effect on the melting temperature for all formulations, which was 45.37° C up to 47.58° C, inferring with this the absence of significant interactions between the lipid carrier and microencapsulated ingredients, absence that was reaffirmed by the infrared spectra. Microencapsulation favored the survival against gastric and simulated intestinal fluids, and was possible to maintain viable cells up to 106 CFU per gram up to 120 days of storage for formulation with L. acidophilus and polydextrose in low temperatures and relative humidity (11%), which the stability was influenced by the water activity of the particle, which in turn is affected by the incorporation of prebiotics to the formulation of the SLMs. Given the potential of SLMs developed, they were incorporated into the ice cream. In this matrix microparticles not performed well, either on the survival of L. acidophilus during product storage, such as in protection against exposure to simulated gastrointestinal conditions. Furthermore, the addition of SLMs on strawberry ice cream was evaluated with grades significantly lower (p ≤ 0.05) in the attributes texture, flavor and overall acceptability compared to the control samples and with added of free probiotic sensory analysis of the product developed. The lipid microparticles produced were shown to be suitable as a food ingredient, but the ice cream did not meet the assumptions of protection and extension of appropriate probiotic counts. The MSLs were also incorporated in the fruit pulp, avocado and melon, in this application the SLMs provided protection to the micro-organism increasing the probiotic viability in relation to the free microorganisms.
53

Desenvolvimento e caracterização de géis polissacarídicos carregados com emulsões e enriquecidos com nutrientes para suplementação de alimentação de leitões / Development and characterization of emulsion-filled polysaccharide gels enriched with nutrients for feeding supplementation of piglets

Souki, Nayla Padua Del Bianco Gontijo 17 March 2017 (has links)
O presente trabalho de Mestrado teve como objetivo produzir géis carregados de emulsão contendo nutrientes incorporados, visando a complementação da alimentação de leitões neonatos. Para alcançar tal objetivo, foram produzidas emulsões utilizando-se diferentes lipídios e tensoativos para definição preliminar sobre quais destes ingredientes seriam mais eficientes na formação de emulsões estáveis. As emulsões produzidas foram avaliadas em relação à distribuição de tamanho de gota e aspecto visual dentro de 24 h após a produção. A partir de tais resultados, algumas amostras foram escolhidas e foi estudado o aumento da concentração de lipídios, bem como a razão óleo:tensoativo e intensidade de agitação. Para cada emulsão estudada, esta era incorporada ao gel polissacarídico, e então realizava-se um estudo da estabilidade térmica a 40 e 50 °C. Após a definição da melhor concentração de lipídios, ocorreu o estudo da incorporação de nutrientes em diversas concentrações na emulsão. Novamente, as emulsões foram avaliadas por meio da distribuição de tamanho de gota, bem como pelo aspecto visual. Foi avaliada a estabilidade da emulsão ao longo de 28 dias, que indicou um sistema estável para o período indicado. Os géis carregados foram analisados quanto à quantidade de energia e à atividade de água, apresentando um baixo valor energético e atividade de água alta. Foram também caracterizados por análises reológicas, que indicaram que a presença da emulsão fortaleceu a estrutura do gel, indicando adesão das gotas à matriz biopolimérica. O gel carregado de emulsão apresentou estabilidade microbiológica, não tendo havido crescimento de fungos filamentosos e não-filamentosos, bem como a manutenção do pH. No entanto, houve alteração da cor ao longo da estocagem. Assim, foi possível produzir um gel carregado de emulsão contendo nutrientes, possibilitando a formação de um sistema estável. / The aim this work was to produce emulsion filled gels with the incorporation of nutrients for the complementation of nutrition of neonates piglets. For this, the emulsions were produced from a variety of lipids and surfactants to define, preliminarily, which of these ingredients would be efficient to form stable emulsions. The emulsions produced were evaluated by droplet size distribution and visual appearance within 24 hours after production. From these results, some samples were selected and the increase of lipid concentration was studied as well as the ratio oil:surfactant and the stirring intensity. For each emulsion studied, this was incorporated into the polysaccharide gel and then the thermal stability study at 40 and 50 °C was made. After setting the optimal concentration of lipids and a stirring intensity, there was the study of nutrientse incorporation at different concentrations in the emulsion. Again, the emulsions were evaluated by droplet size distribution, as well as by visual appearance. The emulsion stability was evaluated over 28 days, which indicated a stable system for this time. The emulsion filled gels were characterized for the amount of energy and water activity and presented as results low amount of energy and high water activity. In the rheological characterization, the results showed that the presence of emulsion strengthened the gel structure, indicating adhesion of the droplets to the biopolymer matrix. The emulsion filled gel showed microbiological stability has not been growing of filamentous and non-filamentous fungi, as well as pH stability. However, there was a change in color over the storage. Thus, it was possible to produce an emulsion-filled gel with nutrients, on which occurred the formation of a stable system.
54

Desenvolvimento e caracterização de produto tipo patê de base láctea potencialmente simbiótico / Development and characterization of a potentially synbiotic dairy-based spread product

Staliano, Cristina Dini 09 February 2012 (has links)
Uma notável tendência na área de alimentos é o desenvolvimento de produtos que agreguem sabor, praticidade, conveniência e tragam benefícios à saúde. Dentro desse cenário, encontram-se os alimentos funcionais, que têm sido alvos de pesquisas científicas para elucidar os benefícios que trazem ao homem. Os probióticos e prebióticos são os ingredientes fisiologicamente ativos que compõem o alimento e agem na manutenção do equilíbrio da microbiota do trato gastrintestinal humano. A combinação de probióticos e prebióticos resulta em um produto simbiótico. Com outro apelo de alimento funcional, pode-se citar o tomate, fruto que apresenta licopeno em sua composição, pigmento com potencial antioxidante e ação preventiva contra diversos tipos de câncer. O presente trabalho teve como objetivo desenvolver um produto tipo patê potencialmente simbiótico, à base de queijo quark, adicionado de derivados de tomate, manjericão e queijo parmesão, bem como avaliar as suas características físico-químicas, microbiológicas, de textura instrumental e sua aceitabilidade sob o ponto de vista sensorial durante o seu armazenamento a 4 ± 1 °C por até 28 dias. Foram produzidos três tratamentos do produto tipo patê (em triplicata), todos eles suplementados com inulina: T1 (controle) com a cultura starter Streptococcus thermophilus ST-M6; T2 com a cultura starter ST-M6 e a adição dos probióticos Bifidobacterium animalis subsp. lactis Bb-12 e Lactobacillus acidophilus NFCMe T3 com a cultura starterST-M6, a cultura probiótica Bb-12 e a adição de Lactobacillus sakei 2a. Os produtos foram armazenados a 4 ± 1 °C e durante os períodos de amo stragem (1, 7, 14, 21 e 28 dias), foi analisada a viabilidade dos probióticos, da cultura starter e de L. sakei 2a, a fim de avaliar a possível adaptação desta cepa bacteriocinogênica ao meio lácteo, uma vez que foi isolada de linguiça frescal. Adicionalmente, o pH e o perfil de textura instrumental do produto (teste de dupla penetração de amostras em analisador de textura TA-XT2) foram analisados e, a partir de amostras mantidas congeladas no dia seguinte à sua fabricação, foi determinada a composição centesimal das diferentes formulações. Além disso, aos 7, 14 e 21 dias, as amostras foram avaliadas sensorialmente (teste de aceitabilidade com escala hedônica estruturada de 9 pontos) por 50 provadores em cada seção. Paralelamente, foi feito um monitoramento microbiológico das amostras quanto à presença de contaminantes. O pH dos três tratamentos apresentou uma queda significativa ao longo dos 28 dias (0,16 a 0,21) e foi significativamente menor (p<0,05) para T2 (4,67 após 28 dias) em relação a T1 (4,85) e T3 (4,76). Quanto à viabilidade da cultura starter, os produtos apresentaram populações médias ao longo do armazenamento sempre acima de 8,95 log UFC/g. As culturas probióticas NCFM e Bb-12 apresentaram contagens acima do mínimo recomendado pela legislação durante o armazenamento, com populações acima de 8 log UFC/g para Bb- 12 e populações de NCFM que diminuíram significativamente (p<0,05) de 8,61 (7 dias) a 7,93 log UFC/g (28 dias) para T2. L. sakei 2a mostrou-se adaptar bem ao produto lácteo, com viabilidade que se manteve na faixa de 8,10 a 8,18 log UFC/g ao longo dos 28 dias. Quanto ao perfil de textura, T2 foi mais estável durante o armazenamento, com parâmetros mais constantes ao longo do estudo, em comparação a T1 e T3. Na análise sensorial, não foram encontradas diferenças significativas (p>0,05) entre os tratamentos durante os dias avaliados e, tampouco, entre os dias estudados para um mesmo tratamento. As amostras tiveram uma boa aceitação pelos provadores, principalmente T2, com notas médias acima de 7 (gostei regularmente), apesar de não diferirem significativamente. O produto inovador tipo patê de base láctea no sabor tomate desenvolvido mostrou-se um bom veículo para os micro-organismos probióticos B. animalis Bb-12 e L. acidophilus NCFM e para L. sakei 2a, potencialmente simbiótico e sensorialmente aceitável. / A remarkable trend in the food area is the development of products that are tasty, convenient, and able to bring healthy benefits. Within this scenario, functional foodshave been object of scientific studies to elucidate their benefits to the human being. Probiotics and prebiotics are physiologically active ingredients in food which positively influence the maintenance of the human gastrointestinal tract balance. A synbiotic product combines probiotic and prebiotics ingredients. The tomato is also remarkable, regarding some compounds with functional attributes in its composition. Lycopene is the pigment present in the fruit that has antioxidant potential and is correlated with reduced incidence of some cancer types. This study aimed to develop a potentially synbiotic quark cheese-based spread product containing tomato and with basil and parmesan cheese, as well as evaluating its physico-chemical and microbiological features, and its instrumental texture profile and sensory acceptability, during storage at 4 ± 1 °C f or up to 28 days. Three different trials of quark cheese-based spread product were produced (in triplicates), all supplemented with inulin: T1 (control) with the starter culture Streptococcus thermophilus ST-M6; T2 with the starter culture ST-M6 plus the addition of the probiotics Lactobacillus acidophilus NCFM and Bifidobacterium animalis subsp. lactis Bb-12, and T3 with the starter culture ST-M6, the probiotic culture Bb-12, and the addition of Lactobacillus sakei 2a. The products were stored at 4 ± 1 °C and, duri ng the sampling periods (1, 7, 14, 21, and 28 days), the viability of probiotics, starter culture, and L. sakei 2a was assessed. The adaptation of L. sakei 2a to the dairy matrix was also evaluated, once this bacteriocin-producing strain was isolated from a Brazilian sausage. Additionally, the pH and instrumental texture profile of the product was assessed (double penetration of samples test, using a TA-XT2 texture analyzer), and the chemical composition was determined, using samples kept frozen after the first day of production. Besides, the trials were sensory evaluated (acceptability test, using a 9-point structured hedonic scale), after 7, 14, and 21 days, by 50 consumers in each session. At the same time, samples were microbiologically monitored for the presence of contaminants. The pH of the three trials displayed a significantly decrease throughout the 28 days of storage (0.16 up to 0.21), and it was significantly lower (p<0.05) for T2 (4.67 after 28 days), compared to T1 (4.85) and T3 (4.76). Regarding the viability of the starter culture, the products showed mean populations always above 8.95 log CFU/g during storage. The probiotic cultures NCFM and Bb-12 displayed counts above the minimum recommended by the Brazilian regulatory standards throughout storage, with populations above 8 log CFU/g for Bb-12, and counts of NCFM decreased significantly (p<0.05) from 8.61 (7 days) to 7.93 log CFU/g (28 days) for T2. L. sakei 2a was able to adequately adapt to the dairy product, with populations that maintained between 8.10 and 8.18 log CFU/g during the 28 days of storage. With respect to the texture profile, T2 was considered the most stable trial during storage, as displayed preservation ofmore homogeneous parameters throughout study, compared to T1 and T3. Regarding sensory evaluation, there were neither significantly differences (p>0,05) among the trials during the studied period nor among the studied periods for the same trial. The samples had a good acceptance by consumers, with mean scores above 7 (like regularly), mainly T2, although the trials did not differ significantly. The innovative tomato dairy-based spread product developed revealed to be an adequate matrix for the probiotic microorganisms B. animalis Bb-12 and L. acidophilus NCFM, and for L. sakei 2a, potentially synbiotic, and sensory acceptable.
55

Estudo da viabilidade de microrganismos probióticos encapsulados em matriz polimérica natural contendo ingredientes prebióticos e fibras alimentares / Study of the viability of probiotic microorganisms naturally encapsulated in polymeric matrix containing probiotics and dietary fiber ingredients

Aline Francisca de Souza 14 August 2015 (has links)
A saúde e o bem estar estão diretamente relacionados com a alimentação saudável. O consumo de alimentos funcionais como fibras, ingredientes prebióticos e probióticos pode promover diversos benefícios para a saúde, como a melhoria do funcionamento do organismo e a prevenção de diversas doenças. Neste contexto, o presente trabalho teve como objetivo estudar o encapsulamento de Lactobacillus delbrueckii UFV H2B20 em matriz polimérica natural constituída por alginato e farinhas de banana verde, maracujá, feijão branco, maçã e laranja. Para tanto, foi realizado planejamento fatorial 24 completo visando a identificação dos parâmetros que influenciam na eficiência do encapsulamento em diferentes matrizes poliméricas e na viabilidade celular do micro-organismo probiótico estudado. As variáveis independentes estudadas foram velocidade de agitação, volume de tween 80, alginato e farinhas funcionais. Os resultados demonstraram que a técnica de emulsificação utilizada apresentou alta eficiência de encapsulamento (acima de 80 %) das células de L. delbrueckii UFV H2B20 nas diferentes matrizes poliméricas estudadas. A análise dos resultados mostrou que os principais parâmetros que afetaram a microencapsulação de L. delbrueckii UFV H2B20 foram a velocidade de agitação e a concentração de alginato. Em condições de fluido gástrico simulado (FGS), somente as microcápsulas constituídas de alginato e farinha de banana verde ou maracujá apresentaram sobrevivência média de 60,5 % e 41,0 %, respectivamente, após 30 minutos de exposição ao FGS, sendo selecionadas para os estudos posteriores. A adição de inulina à matriz polimérica contendo alginato e farinha de banana verde ou maracujá apresentou eficiência de encapsulamento acima de 80 %, porém não conferiu proteção às células quando expostas a condições de FGS. Verificou-se também que após 28 dias de armazenamento, a 4°C ou em sorvete a -18°C, a sobrevivência das células de L. delbrueckii UFV H2B20 microencapsuladas em matriz contendo farinha de banana verde ou maracujá foi superior a 90 %. A adição de sacarose ou leite desnatado reconstituído na referida matriz não interferiu significativamente na proteção das células microencapsuladas quando armazenadas a 4° C ou em sorvete a -18°C. Estes resultados revelaram que as farinhas de banana verde e maracujá, quando associadas ao alginato de sódio, são promissoras para a microencapsulação de bactérias probióticas, nas condições do presente trabalho. / Health and wellness are directly related to the consumption of healthy foods containing functional ingredients such as fibers, pre- and probiotics, which promote many health benefits, regarding body functions and prevention of several diseases. Therefore, this work aimed to study the encapsulation of Lactobacillus delbrueckii UFV H2B20, by emulsification technique, in natural polymeric matrices composed of alginate and flours of pulp of unripe banana, passion fruit husk, integral white beans, bagasse of apple and orange. The experiments were undertaken based on a 24 factorial design in order to identify the parameters that affect the encapsulation efficiency in different polymer matrices and microorganisms viability, as well. It was studied the effect of stirring speed, and concentrations of Tween 80, sodium alginate and the mentioned functional flours. The results showed that the emulsification technique showed high encapsulation efficiency (> 80%) of the Lactobacillus cells in the different polymer matrices evaluated. In addition, the main parameters that affected microencapsulation of L. delbrueckii UFV H2B20 included stirring speed and alginate concentration. Regarding the \"simulated gastric fluid\" (SGF) assays, microcapsules made of alginate, and flours of pulp of unripe banana or husk of passion fruit showed cell survival average than 60,5 % and 41,0 %, respectively, after 30 minutes of exposure to SGF, being selected for further studies. Although the addition of inulin to the polymeric matrix containing alginate and flour of unripe banana pulp or husk of passionfruit presented encapsulation efficiency higher than 80%, they did not show any protection effect to the cells when exposed to SGF. It was also showed, after 28 days of storage at 4 °C or in ice cream at -18 °C, that the cell survival of L. delbrueckii UFV H2B20 microencapsulated in matrices containing flours of unripe banana pulp or husk of passion fruit was higher than 90%. The addition of sucrose or reconstituted skim milk in these matrixes, as thermoprotector, did not interfere significantly in the protection of microencapsulated cells when stored at 4 °C or -18 °C. These results revealed that flours made of unripe banana pulp and husk of passion fruit, when combined with sodium alginate, represent a promising alternative for microencapsulation of probiotic bacteria under the conditions evaluated in this work.
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Desenvolvimento de queijo caprino tipo petit-suisse simbiótico com polpa de açaí (Euterpe oleracea Martius) / Development of synbiotic caprine petit-suisse cheese with açai (Euterpe oleracea Martius) pulp.

Antonio Diogo Silva Vieira 11 October 2013 (has links)
Os objetivos do trabalho foram desenvolver um queijo petit-suisse simbiótico a partir de leite de cabra e polpa de açaí, com a cultura probiótica Lactobacillus paracasei LPC-37 e os prebióticos inulina e fruto-oligossacarideos (FOS), verificar a viabilidade e sobrevivência do probiótico no produto e frente às condições gástricas e entéricas simuladas in vitro e avaliar as características dos queijos ao longo de seu armazenamento a 4ºC, bem como comparar o queijo petit-suisse simbiótico de cabra com o similar produzido a partir de leite de vaca. O delineamento experimental consistiu-se de três tipos de queijo petit-suisse caprino, em triplicata, todos utilizando S.thermophilus TA-40 como cultura starter: QCC = controle; QCP = probiótico (com cultura probiótica LPC-37); QCS = queijo simbiótico (com LPC-37 + prebióticos). Os queijos foram armazenados a 4ºC e analisados semanalmente por até 28 dias. Adicionalmente, para fins de comparação com o QCS, foi, também, produzido um queijo similar com leite de vaca: QVS = queijo simbiótico de leite de vaca (com culturas starter e probiótica LPC-37 + prebióticos). A viabilidade dos probióticos e da cultura starter, a sobrevivência in vitro do probiótico incorporado aos produtos frente às condições gastrintestinais simuladas, bem como as análises de pH, acidez titulável e dureza instrumental dos queijos foram monitorados no produto final e semanalmente até 28 dias de armazenamento. A partir de amostras do dia 1 de armazenamento mantidas congeladas e liofilizadas, respectivamente, foi determinada a sua composição centesimal e de ácidos graxos. A aceitabilidade sensorial dos queijos frente a públicos de duas localidades distintas - de Sobral/CE e de São Paulo/SP foi realizada, respectivamente, aos 7, 14, 21 dias e aos 14 e 21 dias de armazenamento dos queijos. A avaliação sensorial em São Paulo foi conduzida somente em dois pontos, em virtude de dificuldades quanto à logística, envolvendo o transporte dos queijos até São Paulo. Os queijos petit-suisse caprinos apresentaram populações de LPC-37 superiores a 7,93 log UFC/g até 28 dias de armazenamento. As populações de S. thermophilus tiveram reduções significativas (p<0,05) de até 1 ciclo log ao longo do armazenamento nos queijos QCP e QCS. A sobrevivência in vitro de LPC-37 foi baixa, com uma taxa de sobrevivência decrescente ao longo do armazenamento de QCS (de 47,0 para 32,5%) e de QVS (de 48,8 para 30,0%) e crescente para QCP (de 26,5 para 55,9%) para na fase entérica. Quanto à sobrevivência in vitro da LPC-37 na fase gástrica, o queijo de leite de vaca mostrou maior queda da taxa de sobrevivência (de 54,5 para 44,4%) ao longo do armazenamento (p<0,05). A adição de prebióticos influenciou significativamente (p<0,05) o aumento da dureza do queijo QCS. Não foi observada diferença (p>0,05) entre a aceitabilidade dos queijos caprinos frente aos consumidores das duas localidades avaliadas, com exceção do QCS aos 21 dias, onde se observou uma menor aceitabilidade por parte dos consumidores de São Paulo, os quais também revelaram menores intenções de compra. Entre os queijos simbióticos, o de vaca (QVS) foi mais aceito que o seu equivalente de cabra (QCS) em ambas as localidades, com intenção de compra >80% e >55%, respectivamente, em Sobral e em São Paulo. Os resultados revelaram que os queijos petit-suisse caprinos apresentam-se como matrizes alimentares adequadas para a incorporação de L. paracasei LPC-37 em combinação com os prebióticos inulina e FOS, com boa aceitabilidade sensorial, principalmente pelos consumidores de Sobral/CE. / This study aimed to develop a synbiotic petit-suisse from goat milk and acai pulp, with the probiotic strain Lactobacillus paracasei LPC-37 and the prebiotic ingredients inulin and fructo-oligosaccharides (FOS), to verify the probiotic viability in the product and its survival under in vitro simulated gastric and enteric conditions and the characteristics of cheeses during storage at 4 ºC, and to compare the goat synbiotic petit-suisse cheese with the equivalent product produced from cow\'s milk. The experimental design consisted of three types of goat petit-suisse cheese, in triplicates, all of them produced using S.thermophilus TA-40 as the starter culture: CGC = control goat cheese; PGC = probiotic goat cheese (with LPC-37); SGC = synbiotic goat cheese (with LPC-37 + prebiotics). The cheeses were stored at 4 ºC and analyzed weekly for up to 28 days. Additionally, for comparison purposes with the SGC, a similar cheese produced from cow\'s milk: SCC = synbiotic cow cheese (with the starter and the probiotic culture LPC- 37 + prebiotics). The viability of the probiotic and of the starter culture, the probiotic survival under in vitro simulated gastrointestinal, as well as the pH, titratable acidity, and instrumental hardness of cheeses were monitored in the final product and weekly until 28 days of storage. Cheese samples were kept frozen and freeze-dried one day after production, respectively, for analyses of their chemical composition and their fatty acids profile. The sensory acceptability of cheeses by consumers from two different locations - Sobral/ CE and São Paulo/ SP was conducted, respectively, on days 7, 14, and 21 and on days 14 and 21 of storage. Sensory evaluation in São Paulo was conducted at two points due to difficulties regarding transportation of the cheeses to São Paulo.The petit-suisse goat cheeses LPC-37 populations were always above 7.93 log CFU/ g up to 28 days of storage. Populations of S. thermophilus presented significant reductions (p <0.05), up to 1 log cycle, during storage of cheeses PGC and SGC. The in vitro survival of LPC-37 was low, with a decreasing survival rate during storage of SGC (from 47.0 to 32.5%) and SCC (from 48.8 to 30.0%) and an increasing survival for PGC (from 26.5 to 55.9%) during the enteric phase. As for the in vitro survival of LPC-37 in the gastric phase, cheese from cow\'s milk showed a higher decrease in the survival rate (from 54.5 to 44.4%) during storage (p <0,05). The addition of prebiotics significantly increased (p <0.05) the hardness of SGC. No significant difference was observed (p> 0.05) between the acceptability of goat cheeses by the consumers of the two localitions evaluated, except for the SGC on day 21, for which a lower acceptability was observed for the consumers of São Paulo, who also revealed lower purchase intentions. Among the synbiotic cheeses, the cow cheese (SCC) was more accepted than the equivalent goat cheese (SGC) in both locations, with the purchase intentions above 80% and above 55%, respectively, in Sobral and in São Paulo. The results showed that the goat petit-suisse cheeses revealed to be suitable as food matrices for the incorporation of L. paracasei LPC-37 in combination with the prebiotics inulin and FOS, with good sensory acceptability, especially regarding consumers of Sobral/ CE.
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In vitro evaluation of the prebiotic effects of sugar alcohols.

January 2006 (has links)
Ma Ka Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 99-118). / Abstracts in English and Chinese. / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- What are prebiotics? --- p.1 / Chapter 1.2 --- Current prebiotics and their development --- p.2-3 / Chapter 1.3 --- The intestinal microflora --- p.3-4 / Chapter 1.3.1 --- Bacteroides --- p.5 / Chapter 1.3.2 --- Bifidobacteria --- p.5 / Chapter 1.3.3 --- Clostridia --- p.5-6 / Chapter 1.3.4 --- Lactobacilli --- p.6 / Chapter 1.4 --- Bacterial colonic fermentation --- p.7-8 / Chapter 1.4.1 --- Carbohydrates metabolism in colonic bacteria --- p.8-10 / Chapter 1.4.1.1 --- Carbohydrates metabolism in Bacteroides --- p.11 / Chapter 1.4.1.2 --- Carbohydrates metabolism in Bifidobacteria --- p.11 / Chapter 1.4.1.3 --- Carbohydrates metabolism in Clostridia --- p.11 / Chapter 1.4.1.4 --- Carbohydrates metabolism in Lactobacilli --- p.12 / Chapter 1.5 --- Health benefits of prebiotics --- p.12-13 / Chapter 1.6 --- Metabolites of fermentation: Short-chain fatty acids (SCFAs) --- p.14-15 / Chapter 1.7 --- Applications of prebiotics as functional food ingredients --- p.16 / Chapter 1.8 --- Methodology for evaluating prebiotics --- p.17 / Chapter 1.8.1 --- In vivo fermentation study --- p.17 / Chapter 1.8.2 --- Human clinical study --- p.17-18 / Chapter 1.8.3 --- In vitro fermentation study --- p.18-19 / Chapter 1.9 --- Methods of bacterial enumeration --- p.19-20 / Chapter 1.9.1 --- Fluorescent in situ hybridisation --- p.20-22 / Chapter 1.9.2 --- Bacterial enumeration by automatic image analysis --- p.22-23 / Chapter 1.10 --- Sugar alcohols --- p.23 / Chapter 1.10.1 --- Sugar alcohols and their functions --- p.23-25 / Chapter 1.10.2 --- Digestion and absorption of sugar alcohols --- p.25-26 / Chapter 1.10.3 --- Metabolism of sugar alcohols in humans --- p.26 / Chapter 1.10.4 --- Adverse effect of sugar alcohols --- p.26-27 / Chapter 1.11 --- Fermentation of sugar alcohols in colonic bacteria --- p.27 / Chapter 1.12 --- Project objectives --- p.28 / Chapter Chapter 2. --- Materials and Methods --- p.29 / Chapter 2.1 --- Materials --- p.29 / Chapter 2.2 --- Static batch culture fermentation --- p.29 / Chapter 2.2.1 --- Substrate preparation --- p.29-30 / Chapter 2.2.2 --- Human fecal inoculum preparation --- p.30-31 / Chapter 2.3 --- Dry matter and organic matter disappearance in batch fermentation --- p.31 / Chapter 2.4 --- Determination of flow rate in the continuous fermentation system. --- p.32-33 / Chapter 2.5 --- Three-stage continuous fermentation culture system --- p.34 / Chapter 2.5.1 --- Initial set-up --- p.34-35 / Chapter 2.5.2 --- Continuous fermentation --- p.35-36 / Chapter 2.6 --- Validation of fluorescent in situ hybridisation (FISH) method --- p.36 / Chapter 2.6.1 --- Oligonucleotide probes for FISH --- p.36-37 / Chapter 2.6.2 --- Cultivation of pure human intestinal bacterial culture --- p.37-38 / Chapter 2.6.3 --- Validation of oligonucleotide probes for FISH --- p.38-40 / Chapter 2.7 --- Bacterial enumeration of fermentation broth by FISH --- p.41 / Chapter 2.7.1 --- Automated image analysis --- p.41-42 / Chapter 2.7.2 --- Quantification of bacteria --- p.43 / Chapter 2.8 --- Gas chromatographic determination of short-chain fatty acids (SCFAs) --- p.44-46 / Chapter 2.9 --- Statistical analysis --- p.46 / Chapter Chapter 3: --- Results and Discussion --- p.47 / Chapter 3.1 --- Dry matter and organic matter disappearance in batch fermentations --- p.47-48 / Chapter 3.2 --- Validation of genus-specific oligonucleotide probes for FISH by pure bacterial culture --- p.48-50 / Chapter 3.3 --- FISH and multi-color FISH of human fecal bacteria --- p.50-53 / Chapter 3.4 --- Enumeration of fecal bacteria with the CellC software --- p.53-54 / Chapter 3.5 --- Colonic bacterial profile in batch culture in vitro fermentation --- p.55 / Chapter 3.5.1 --- Total colonic bacteria --- p.55-56 / Chapter 3.5.2 --- Bacteroides --- p.57-59 / Chapter 3.5.3 --- Bifidobacteria --- p.60-62 / Chapter 3.5.4 --- Clostridia --- p.63-64 / Chapter 3.5.5 --- Lactobacilli --- p.65-66 / Chapter 3.6 --- Short-chain fatty acids (SCFAs) in batch in vitro fermentation --- p.67 / Chapter 3.6.1 --- Total SCFAconcentration --- p.67-68 / Chapter 3.6.2 --- Acetate --- p.68 / Chapter 3.6.3 --- Propionate --- p.69 / Chapter 3.6.4 --- Butyrate --- p.69-70 / Chapter 3.7 --- Determination of flow rate in three-stage continuous fermentation system --- p.71-73 / Chapter 3.8 --- Colonic bacterial profile in three-stage continuous fermentation system --- p.74 / Chapter 3.8.1 --- Total colonic bacteria --- p.74-75 / Chapter 3.8.2 --- Bacteroides --- p.76 / Chapter 3.8.3 --- Bifidobacteria --- p.77-78 / Chapter 3.8.4 --- Clostridia --- p.79-80 / Chapter 3.8.5 --- Lactobacilli --- p.81 / Chapter 3.9 --- SCFAs in three-stage continuous fermentation system --- p.82 / Chapter 3.9.1 --- Total SCFA concentration --- p.82-87 / Chapter 3.9.2 --- SCFA molar ratio --- p.88-89 / Chapter 3.9.3 --- Acetate --- p.90-91 / Chapter 3.9.4 --- Propionate --- p.92-93 / Chapter 3.9.5 --- Butyrate --- p.94-95 / Chapter Chapter. 4 --- Conclusions and Future Works --- p.96-98 / List of References --- p.99-117 / Related Publications --- p.118
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Estudo da viabilidade de microrganismos probióticos encapsulados em matriz polimérica natural contendo ingredientes prebióticos e fibras alimentares / Study of the viability of probiotic microorganisms naturally encapsulated in polymeric matrix containing probiotics and dietary fiber ingredients

Souza, Aline Francisca de 14 August 2015 (has links)
A saúde e o bem estar estão diretamente relacionados com a alimentação saudável. O consumo de alimentos funcionais como fibras, ingredientes prebióticos e probióticos pode promover diversos benefícios para a saúde, como a melhoria do funcionamento do organismo e a prevenção de diversas doenças. Neste contexto, o presente trabalho teve como objetivo estudar o encapsulamento de Lactobacillus delbrueckii UFV H2B20 em matriz polimérica natural constituída por alginato e farinhas de banana verde, maracujá, feijão branco, maçã e laranja. Para tanto, foi realizado planejamento fatorial 24 completo visando a identificação dos parâmetros que influenciam na eficiência do encapsulamento em diferentes matrizes poliméricas e na viabilidade celular do micro-organismo probiótico estudado. As variáveis independentes estudadas foram velocidade de agitação, volume de tween 80, alginato e farinhas funcionais. Os resultados demonstraram que a técnica de emulsificação utilizada apresentou alta eficiência de encapsulamento (acima de 80 %) das células de L. delbrueckii UFV H2B20 nas diferentes matrizes poliméricas estudadas. A análise dos resultados mostrou que os principais parâmetros que afetaram a microencapsulação de L. delbrueckii UFV H2B20 foram a velocidade de agitação e a concentração de alginato. Em condições de fluido gástrico simulado (FGS), somente as microcápsulas constituídas de alginato e farinha de banana verde ou maracujá apresentaram sobrevivência média de 60,5 % e 41,0 %, respectivamente, após 30 minutos de exposição ao FGS, sendo selecionadas para os estudos posteriores. A adição de inulina à matriz polimérica contendo alginato e farinha de banana verde ou maracujá apresentou eficiência de encapsulamento acima de 80 %, porém não conferiu proteção às células quando expostas a condições de FGS. Verificou-se também que após 28 dias de armazenamento, a 4°C ou em sorvete a -18°C, a sobrevivência das células de L. delbrueckii UFV H2B20 microencapsuladas em matriz contendo farinha de banana verde ou maracujá foi superior a 90 %. A adição de sacarose ou leite desnatado reconstituído na referida matriz não interferiu significativamente na proteção das células microencapsuladas quando armazenadas a 4° C ou em sorvete a -18°C. Estes resultados revelaram que as farinhas de banana verde e maracujá, quando associadas ao alginato de sódio, são promissoras para a microencapsulação de bactérias probióticas, nas condições do presente trabalho. / Health and wellness are directly related to the consumption of healthy foods containing functional ingredients such as fibers, pre- and probiotics, which promote many health benefits, regarding body functions and prevention of several diseases. Therefore, this work aimed to study the encapsulation of Lactobacillus delbrueckii UFV H2B20, by emulsification technique, in natural polymeric matrices composed of alginate and flours of pulp of unripe banana, passion fruit husk, integral white beans, bagasse of apple and orange. The experiments were undertaken based on a 24 factorial design in order to identify the parameters that affect the encapsulation efficiency in different polymer matrices and microorganisms viability, as well. It was studied the effect of stirring speed, and concentrations of Tween 80, sodium alginate and the mentioned functional flours. The results showed that the emulsification technique showed high encapsulation efficiency (> 80%) of the Lactobacillus cells in the different polymer matrices evaluated. In addition, the main parameters that affected microencapsulation of L. delbrueckii UFV H2B20 included stirring speed and alginate concentration. Regarding the \"simulated gastric fluid\" (SGF) assays, microcapsules made of alginate, and flours of pulp of unripe banana or husk of passion fruit showed cell survival average than 60,5 % and 41,0 %, respectively, after 30 minutes of exposure to SGF, being selected for further studies. Although the addition of inulin to the polymeric matrix containing alginate and flour of unripe banana pulp or husk of passionfruit presented encapsulation efficiency higher than 80%, they did not show any protection effect to the cells when exposed to SGF. It was also showed, after 28 days of storage at 4 °C or in ice cream at -18 °C, that the cell survival of L. delbrueckii UFV H2B20 microencapsulated in matrices containing flours of unripe banana pulp or husk of passion fruit was higher than 90%. The addition of sucrose or reconstituted skim milk in these matrixes, as thermoprotector, did not interfere significantly in the protection of microencapsulated cells when stored at 4 °C or -18 °C. These results revealed that flours made of unripe banana pulp and husk of passion fruit, when combined with sodium alginate, represent a promising alternative for microencapsulation of probiotic bacteria under the conditions evaluated in this work.
59

Desenvolvimento de queijo \'petit-suisse\' simbiótico / Development of a synbiotic \'petit-suisse\' cheese

Haissa Roberta Cardarelli 04 August 2006 (has links)
A associação de ingredientes prebióticos com microrganismos probióticos na elaboração de produtos lácteos pode resultar na obtenção de produtos simbióticos, com os efeitos benéficos dos probióticos, aliado ao estímulo seletivo das bifidobactérias endógenas do cólon. Objetivou-se desenvolver um queijo petit-suisse simbiótico, suplementado com os probióticos Lactobacillus acidophilus e Bifidobacterium lactis e os prebióticos inulina, oligofrutose e mel; avaliar a viabilidade dos probióticos e do starter, a concentração de frutanos, a aceitabilidade sensorial e parâmetros físico-químicos durante o seu armazenamento a 4±1°C por até 28 dias; otimizar as misturas envolvendo os prebióticos, garantindo a boa viabilidade probiótica e o potencial efeito prebiótico, associados a características tecnológicas e sensoriais satisfatórias. Para esse fim, foram desenvolvidas formulações de queijo petit-suisse, com Lactobacillus acidophilus e Bifidobacterium lactis, utilizando Streptococcus thermophilus como starter, conforme o delineamento da superfície de resposta para misturas com três fatores: oligofrutose, inulina e mel. Os fatores foram combinados em diferentes proporções, de modo a obter 10% da formulação final, totalizando 7 ensaios e um controle (T1 a T8). As populações dos probióticos estiveram sempre superiores ao recomendado para a promoção dos efeitos benéficos, tendo variado de 7,20 a 7,69 log ufc g-1 (B. lactis) e de 6,08 a 6,99 log ufc g-1 (L. acidophilus). Os valores de pH decresceram e de acidez cresceram ao longo do tempo, devido à atividade dos microrganismos acidificantes presentes, tendo diferido significativamente entre os ensaios (p<0,05). A umidade permaneceu estável e diferiu significativamente entre os ensaios (p<0,05). O ingrediente que mais afetou a textura instrumental foi a inulina, fornecendo produtos mais firmes, mais coesos e com adesividade e gomosidade maiores. Oligofrutose e mel, como ingredientes únicos, produziram queijo petit-suisse com menor firmeza, adesividade e gomosidade, parâmetros estes correlacionados negativamente com o pH nos diferentes produtos estudados, ao contrário do que ocorreu com a coesividade. Os ensaios não diferiram significativamente quanto à aceitabilidade sensorial com painel de consumidores, exceto aos 28 dias de armazenamento (p<0,05). Aqueles contendo oligofrutose (T1) e oligofrutose mais inulina (T4) foram os mais bem aceitos, enquanto o controle (T8) foi o menos aceito. Todos os resultados ficaram entre \"gostei ligeiramente\" e \"gostei moderadamente\". A aceitabilidade foi crescente durante o armazenamento, significativamente (p<0,05) apenas para os ensaios que continham oligofrutose ou inulina sozinhos e sua combinação. Os atributos mais citados pelos consumidores foram o sabor - mais preferido nos ensaios T1 (oligofrutose), T3 (mel) e T5 (oligofrutose mais mel) e menos preferido no T8 (controle), e a textura, sempre menos preferida, em virtude de \"arenosidade\". Todas as combinações dos ensaios estudadas, exceto o T3 (mel), podem ser consideradas prebióticas, partindo-se da recomendação de 4 a 5 g dia-1 de frutanos e com uma porção diária de 100 g de queijo petit-suisse. A Metodologia da Superfície de Resposta aplicada para otimizar a viabilidade dos probióticos, a firmeza instrumental, o teor de frutanos e o custo, resultou na mistura ótima contendo 25% de oligofrutose, 70% de inulina e 5% de mel e desejabilidade global de 99,55%. / Due to the potential synergy between probiotics and prebiotics, dairy products containing a combination of these ingredients are often referred to as synbiotic, providing the beneficial effects of the probiotics combined with the effect of selectively stimulating the growth and/or activity of bifidobacterium in the colon. The purpose of this study was to develop a synbiotic petit-suisse cheese, supplemented with the probiotics Lactobacillus acidophilus and Bifidobacterium lactis and the prebiotics inulin, oligofructose and honey; to monitor the viability of the probiotics and the starter, the concentration of fructans, and also the sensory acceptance and physico-chemical parameters during refrigerated storage (4±1°C) for up to 28 days; to optimize the mixtures involving the prebiotic ingredients, in order to guarantee good probiotic viability and potential prebiotic effects, together with to satisfactory technological and sensory properties. The formulations were developed according to the surface response methodology for mixtures including three factors: oligofructose, inulin and honey. The prebiotics were combined in different proportions (to achieve 10% of total mixture), and 7 trials plus a control trial were obtained (T1 to T8). Probiotic populations were always above the minimum counts suggested for providing health benefits, and varied from 7.20 up to 7.69 log cfu g-1 (B. lactis) and from 6.08 up to 6.99 log cfu g-1 (L. acidophilus). The pH values decreased and the acidity values increased significantly during storage, and were statistically different in the various trials (P<0.05), due to the acidifying effect of the organisms present. The moisture remained stable during storage and also varied statistically in the trials (P<0.05). Instrumental texture profile was greatly influenced by inulin, resulting in firmer, more cohesive and adhesive products, and with higher gumminess. Oligofructose and honey added as sole ingredients produced a less firm, adhesive and gummy cheese. The pH influenced the instrumental firmness, adhesiveness and gumminess negatively, and cohesiveness positively. There was no significant difference in sensory acceptance for the consumer panel between the different trials, except after 28 days of storage (P<0.05). The acceptance was significantly higher for cheeses supplemented with oligofructose (T1) and oligofructose plus inulin (T4), whereas the control (T8) was less accepted. The results always ranged from like slightly to like moderately. Acceptability increased during storage, though significantly (P<0.05) only for cheeses supplemented with oligofructose and/or inulin. Taste was the most preferred attribute for trials T1 (oligofructose), T3 (honey), and T5 (oligofructose plus honey) and less preferred for T8 (control). Texture attribute was always the least preferred, due to the \"dust\" present. All cheese trials, except T3 (honey), can be considered prebiotic, according to the recommended ingestion of 4 to 5 g day -1 of fructans for a 100g daily portion. The response surface methodology, applied to optimize probiotic viability, instrumental firmness, fructans content and cost, resulted in an optimum mixture containing 25% oligofructose, 70% inulin and 5% honey and global desirability of 99.55%.
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Avalia??o cl?nica e laboratorial do tratamento com lactulose de c?es com doen?a renal cr?nica / Clinical and laboratorial evaluation of the treatment with lactulosis of dogs with chronic kidney disease

PEREIRA, Juliana de Abreu 27 April 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-03-15T19:04:01Z No. of bitstreams: 1 2017 - Juliana de Abreu Pereira.pdf: 2216195 bytes, checksum: 788fd1f8f4db4f3012004d0eec09d439 (MD5) / Made available in DSpace on 2018-03-15T19:04:01Z (GMT). No. of bitstreams: 1 2017 - Juliana de Abreu Pereira.pdf: 2216195 bytes, checksum: 788fd1f8f4db4f3012004d0eec09d439 (MD5) Previous issue date: 2017-04-27 / CAPES / Prebiotics, such as lactulosis, may favor the switch on the fermentative pattern of the colonic microbiota from proteolytic to saccharolytic, which allows bigger assimilation of nitrogenous compounds by the microrganisms of the colon. The present study aimed to evaluate, in dogs with CKD, the effect of the continued orally use of lactulosis over the nitrogenous compounds metabolisms?, the iron metabolism and on serum levels of albumin, magnesium, calcium and phosphorus. Twenty-one animals with CKD in IRIS II and III stages, under normal handling and feeding, were clinically and laboratorially evaluated by a 28 days period; divided in three groups according to treatment: T1 ? lactulosis + therapeutic diet, T2 ? lactulosis + standard treatment + therapeutic diet, T3 ? standard treatment + therapeutic diet . For the three groups (T1, T2 and T3), clinical parameters indicated anaemia and body score from regular to bad, according to the disease?s degree, during the hole treatment. The haematological and biochemical?s averages are consistent with common laboratorial findings in nephrophatic patients, with high levels of urea and creatinine; and low leves of haematocrit. For all the evaluated parameters in this study, the averages? variations during the period didn?t show any significant difference between times and treatments, with the exception of the calcemia averages that were greater for T1 group; which may indicate that for this animals? group the monotherapy with lactulosis could have increased the absorption of this mineral in those patients. With regard to iron metabolism, this study?s data revealed that the anaemia found in the dogs throughout the experimental period presented chronicity features, since the groups? means remained within the iron and transferrin references, besides high ferritin averages, without significant differences between groups and moments. The obtained data allowed to conclude that there was no difference between the proposed treatments in relation to clinical state and the biochemical and mineral profiles, such as iron metabolism; which justifies that the action mechanisms of prebiotics in nephrophatic patients should be evaluated with more details. / Prebi?ticos, como a lactulose, podem favorecer a altera??o do padr?o fermentativo da microbiota col?nica de proteol?tico para sacarol?tico; o que possibilita maior assimila??o de compostos nitrogenados pelos microrganismos do c?lon. O presente estudo teve por objetivo avaliar, em c?es com DRC, o efeito da utiliza??o continuada de lactulose por via oral, sobre o metabolismo de compostos nitrogenados; o metabolismo do ferro, e sobre as concentra??es s?ricas de albumina, magn?sio, c?lcio e f?sforo. Vinte e um animais portadores de DRC em est?gios IRIS II e III, com manejo e alimenta??o normais, foram avaliados clinicamente e laboratorialmente por um per?odo de 28 dias; divididos em tr?s grupos conforme o tratamento: T1 ? lactulose + ra??o terap?utica, T2 ? lactulose + tratamento convencional + ra??o terap?utica, T3 ? tratamento convencional + ra??o terap?utica. Para os tr?s grupos (T1, T2 e T3), os par?metros cl?nicos foram indicativos de anemia e escore corporal de regular a ruim, de acordo com o grau da enfermidade, ao longo de todo tratamento. As m?dias dos par?metros hematol?gicos e bioqu?micos s?o condizentes com achados laboratoriais comuns em nefropatas; com elevados valores de ureia e creatinina e valores decrescidos de hemat?crito. Para todos os par?metros as varia??es durante o per?odo n?o apresentaram diferen?a significativa entre os tempos e tratamentos, ? exce??o das m?dias de calcemia que foram maiores para o grupo T1; o que pode indicar que para os animais deste grupo a monoterapia com lactulose pode ter aumentado a absor??o deste mineral. Com rela??o ao metabolismo de ferro, os dados revelaram que a anemia encontrada nos c?es em todo o per?odo experimental apresentou caracter?sticas de cronicidade, uma vez que as m?dias dos grupos permaneceram dentro dos intervalos de refer?ncia para ferro e transferrina; al?m de m?dias elevadas de ferritina, sem diferen?as significativas entre grupos e momentos. Os dados obtidos permitiram concluir que n?o houve diferen?a entre os tratamentos propostos com rela??o ao estado cl?nico e aos perfis bioqu?micos e minerais, bem como ao metabolismo de ferro; o que justifica que os mecanismos de a??o dos prebi?ticos em nefropatas devem ser avaliados com maiores detalhes.

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