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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.
11

Using a non-diet approach to prevent overweight and obesity among 6th to 8th grade youth in a low-income racial/ethnic community in Kansas

Li, Yijing January 1900 (has links)
Doctor of Philosophy / Department of Food, Nutrition, Dietetics and Health / Tandalayo Kidd / Objective: The purpose of this study is to promote healthy dietary and physical activity (PA) behaviors in adolescents using a six-module nutrition education resource—Wise Eating (WE)—which was designed specifically for the adolescent population based on the concept and principles of Intuitive Eating (IE).  Study Design: Repeated measures study with pre-assessment and post-assessment. Outcome Measures and Analysis: This study assessed participating adolescents’ breakfast intake, fruit and vegetable (FV) consumption, and PA behaviors; perceptions of IE factors; and perceptions of the Theory of Planned Behavior (TPB) variables. Independent samples t-tests and one-way ANOVAs were used to determine differences in demographic variables and differences between the control and the intervention group. Paired t-tests were performed to compare the behavioral and perception changes from the pre-assessment to the post-assessment. Multiple linear regressions were performed to examine the relationship between TPB variables and FV consumption and PA participation intent and behaviors. Results: The total number of participants at the pre- and the post-assessment was 154 and 148, respectively. Participant’s gender and grade level were evenly distributed. Hispanic was identified as the predominant ethnic population at both the pre- and the post-assessment. At post-assessment, participants in the intervention group significantly increased their breakfast intake frequency, FV consumption frequency, and PA participation frequency (P < .05). Sixth graders had significantly higher breakfast intake frequency, FV consumption frequency, and PA participation frequency when compared with 7th and 8th graders (P < .05). The TPB variables significantly predicted FV consumption and PA intent and behaviors at both the pre- and the post-assessment, and the perceived behavioral control served as the most consistent predictor. For the intervention group, the IE total and Factor 1—Unconditional Permission to Eat scores were significantly increased at the post-assessment when compared with the control group (P .001). Conclusions: These findings tested the effectiveness of WE education modules and further emphasized the need for more interventions on IE to improve dietary and PA behaviors change in the adolescent population.
12

Examining the Influence of Price and Accessibility on Willingness to Shop at Farmers' Markets Among Low-Income Eastern North Carolina Women

McGuirt, Jared T., Jilcott Pitts, Stephanie B., Ward, Rachel, Crawford, Thomas W., Keyserling, Thomas C., Ammerman, Alice S. 01 January 2014 (has links)
Objective: To examine the influence of farmers' market pricing and accessibility on willingness to shop at farmers' markets, among low-income women. Design: Qualitative interviews using scenarios with quantitative assessment of willingness to shop at farmers' markets given certain pricing and accessibility scenarios. Setting: Eastern North Carolina. Participants: A total of 37 low-income women of childbearing age (18-44 years) receiving family planning services at the health department. Phenomenon of Interest: Willingness to shop at a farmers' market. Analysis: Fisher's exact test was used to examine associations between willingness to shop at farmers' markets by urban/rural residence, race, and employment status. Direct quotations relevant to participants' use of farmers' markets were extracted based on a positive deviance framework. Results: Participants were increasingly willing to shop at the farmers' market when price savings increased and when the market was incrementally closer to their residence. Willingness was highest when there was at least a 20% price savings. Participants seemed to be influenced more by a visual representation of a greater quantity of produce received with the price savings rather than a quantitative representation of the money saved by the reduced price. Conclusions and Implications: Future farmers' market interventions should take into account these consumer level preferences.
13

The comparison of the relationship between urinary flavonoid metabolites and 1, 2 or 3 days of diet records

Pashkova, Anna 27 August 2019 (has links)
No description available.
14

Effectiveness of a Parent Health Report in Increasing Fruit and Vegetable Consumption Among Preschoolers and Kindergarteners

Hunsaker, Sanita Lisa 01 June 2015 (has links) (PDF)
Patterns of fruit and vegetable consumption begin in childhood and persist into adulthood. Educating parents regarding appropriate dietary requirements for preschoolers is critical to supporting their appropriate growth and development. The purpose of this study was to determine whether a parent health report (including information about the child's fruit and vegetable consumption and recommendations regarding how to increase fruit and vegetable consumption) resulted in a greater fruit and vegetable intake in preschoolers and kindergarteners. Results from both the open trial and the randomized-controlled trial suggest that the parent health report may be a beneficial tool to increase vegetable consumption in preschoolers and kindergarteners. Increases in vegetable consumption can lead to the establishment of lifelong habits of healthy vegetable intake and decrease risk for chronic diseases in the future.
15

Physical health behaviors of gardening and non-gardening parents and their children

Smith, Ann Marie January 1900 (has links)
Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Candice A. Shoemaker / Professionals in health promotion are starting to look at gardening as a strategy for health behavior change. This popular leisure time activity provides access to physical activity and fresh fruits and vegetables for consumption, two behaviors consistently recommended for optimum physical health. Coupled with a lifestyle low in sedentary behavior these behaviors can offset the health risks of the prevailing trends of overweight and obesity. Spending time outdoors is associated with higher levels of physical activity, while screen based behaviors are associated with unhealthy eating. No studies to date have looked at the health behaviors of gardeners, or the effects it may have on their family’s health behaviors. The purpose of this report is to examine, through descriptive research, the health behaviors of gardening and non-gardening parents and their fourth or fifth grade child. Surveys were administered to a convenience sample of 366 fourth and fifth grade students and their guardians within a school district in Riley County, Kansas. The survey assessed the physical health behaviors mentioned above; comparisons were made according to parental classification of gardener (n=189) or non-gardener (n=177). Significant association was found with gardening classification and adult self-reports of the number of days and amount of time respondents participated in moderate to vigorous physical activity. The median days per week parents reported participation in moderate to vigorous physical activity was 3 for non-gardeners, and 4 for gardeners and was influenced by gender. Eighty-seven percent of gardeners compared to 59.3% of non-gardeners reported meeting the current physical activity recommendation of 150 minutes per week of moderate intensity activity.
16

Parental modelling of eating behaviours

Palfreyman, Zoe January 2013 (has links)
At present, the process of parental modelling of eating behaviours and attitudes has received limited research interest. While often mentioned as a possible factor in relation to child feeding and the development of eating behaviours, only a few studies have explicitly researched parental modelling. The main aims of this thesis were to develop a new measure to assess modelling multidimensionally and to explore the relationships between parental modelling of eating behaviours with a variety of parent and child factors. Initially, a parental self-report measure (the Parental Modelling of Eating Behaviours Scale; PARM) was developed, validated and piloted as part of a series of studies exploring the associations between modelling and a range of self-reported parental and child factors. To provide further validation for the PARM, an observational coding scheme was developed, based on the newly developed modelling measure, and this was utilised in two further studies which looked at self-reported and observed parent and child factors. The key findings from this thesis suggest a number of beneficial relationships. For example, maternal modelling was positively correlated with healthy food intake in both mothers and their children. In addition, both maternal and paternal modelling were associated with children s increased enjoyment of food and lower levels of food fussiness. Observations of maternal modelling were also found to be positively related to other observed adaptive, non-directive feeding practices, such as encouragement to eat. However, less positive relationships were also identified, with modelling being related to parents mental health symptoms and to unhealthy food intake in both mothers and their children. In conclusion, this thesis has identified three distinct facets of modelling and highlighted factors which might be linked to parental role modelling around eating behaviours. While much of the research within this thesis is exploratory, and the findings require replication, they would suggest that parental modelling has the potential to positively influence children s eating behaviours. However, parents should also be made aware of the potential detrimental effect that modelling less adaptive eating behaviours may have on their children s food intake, particularly those eating behaviours that parents may be unaware of modelling.
17

Examining the Association of Fruit and Vegetable intake and Breast and Prostate Cancer Screening

Yu, Mark 11 December 2009 (has links)
Breast and prostate cancer incidence and mortality have been steadily decreasing. Reasons for these reductions may be related to increased rates of cancer screening and other factors such as improvements in diet, including consumption of fruits and vegetables. We wanted to determine if individuals who get screened for breast and prostate cancer are more or less likely to consume adequate servings of fruit and vegetables. A cross-sectional study using the BRFSS survey was conducted. Individuals included in this study (n=26,222), were asked about their breast or prostate cancer screening history. They were also asked about their servings per day of fruit and vegetables. Statistical analyses were conducted using the SAS 9.2 software program. Logistic regression analyses were conducted on the variables and potential confounders. Over 40% of individuals who did not screen for breast and prostate cancer were in the 50-59 years of age category. A trend was seen with younger age groups being less likely to consume 3 or more daily servings of fruit and vegetables than their older counterparts. Another trend was seen in education levels. Individuals with lower education were less likely to consume at least 3 daily servings of fruit and vegetables. There was a statistically significant association between cancer screening and servings of fruit and vegetables per day. Individuals who were screened for either breast or prostate cancer were 52% more likely to consume 3 or more servings of fruit and vegetables than those who did not screen for either breast or prostate cancer (OR=1.52, 95% CI: 1.29-1.79). Further research needs to be conducted related to how other health behaviors may be related to cancer screening adherence and fruit/vegetable intake.
18

A relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes / The relationship between self perceived food environment and fruit and vegetable intake by pregnant women.

Zuccolotto, Daniela Cristina Candelas 14 June 2013 (has links)
Introdução: O consumo adequado de frutas, verduras e legumes (FVL) durante a gestação apresenta impacto positivo sobre a saúde da mulher e da criança. Os fatores ambientais associados ao comportamento alimentar vêm recebendo destaque no âmbito da saúde pública por afetar diretamente a saúde dos indivíduos. Entretanto, desconhecemos a existência de estudos que investigaram a relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes. Objetivo: Verificar a reprodutibilidade de um questionário sobre a percepção do ambiente alimentar e para o consumo de frutas e hortaliças em gestantes (manuscrito 1) e avaliar a relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes (manuscrito 2). Metodologia: O estudo de reprodutibilidade (manuscrito 1) foi conduzido em 2010 entre 48 gestantes usuárias do serviço público de saúde de Ribeirão Preto, SP. O questionário é composto por 12 questões de múltipla escolha que incluem a percepção do ambiente alimentar e para o consumo de frutas e hortaliças. Para verificação da reprodutibilidade, o questionário foi aplicado em duplicata, com intervalo entre 15 e 45 dias. A concordância entre as respostas foi avaliada por meio do teste de Kappa ponderado ou Kappa. A relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes (manuscrito 2) foi avaliada empregando-se os dados de um estudo transversal, conduzido em 2012, entre 282 gestantes adultas. O consumo de FVL foi avaliado por meio de um questionário de freqüência alimentar (QFA) , e dois recordatórios de 24 horas. O Multiple Source Method foi utilizado para estimar o consumo usual de FVL. A percepção do ambiente alimentar foi avaliada mediante a aplicação de questionário estruturado. Para a investigação da relação entre a as variáveis da percepção do ambiente alimentar e consumo adequado de FVL (400g/dia), modelos de regressão logística [OR (95% IC)] foram empregados ajustados por escolaridade, idade e classe econômica das gestantes. Resultados: No manuscrito 1, verificou-se a reprodutibilidade do questionário sobre a percepção do ambiente alimentar e para o consumo de frutas e hortaliças em gestantes. Concordância forte (Kappa entre 0,6 e 0,79) para: número de refeições ao dia, hábito de se alimentar no local de trabalho, distância entre a residência e local de aquisição de FVL e qualidade de FVL no local de aquisição. Concordância moderada (Kappa entre 0,4 e 0,59): hábito de se alimentar fora do domicílio, em restaurantes do tipo self-service ou por quilo, em lanchonetes, se adquire alimentos em mercearias, lojas de conveniência ou padaria, motivo da escolha do local para aquisição de FVL, variedade de FVL no local de aquisição e apoio familiar para ter uma alimentação saudável. Concordância fraca (Kappa entre 0,2-0,39): freqüência em que faz refeições na casa de amigos/ parentes, freqüência em que adquire alimentos em supermercados e varejão ou feira livre e percepção em relação ao preço de FVL. As questões que obtiveram concordância fraca foram reformuladas previamente a sua utilização. No manuscrito 2 observou-se que 35% das mulheres estudadas reportaram o Resumo consumo adequado de frutas e hortaliças durante a gestação, não encontrando uma associação direta entre a percepção do ambiente alimentar e o consumo adequado de frutas e hortaliças entre elas. Entretanto, as gestantes que relataram ter o hábito de fazer quatro ou mais refeições ao dia apresentaram maior chance de consumir a quantidade adequada de furtas e hortaliças quando comparadas àquelas que relataram menor número de refeições ao dia [OR 2.01 (95% IC 1.03, 3.91) p 0.04]. Da mesma forma, as mulheres que referiram o hábito de comprar FVL em varejão ou feira livre apresentaram maior chance de atingir a recomendação de frutas e hortaliças, independente de idade, escolaridade e classe socioeconômica [OR 1.68 (IC95% 1.01, 2.80) p 0.05]. Conclusão: O questionário sobre a percepção do ambiente alimentar e para o consumo de FVL apresentou boa precisão entre gestantes. Não houve associação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças entre as gestantes estudadas. / Introduction: The adequate intake of fruits and vegetables (FV) during pregnancy has a positive impact on the health of women and children. Environmental factors associated with eating behavior have received attention in the context of public health by directly affecting individuals health. However, unaware of the existence of studies that investigated the relationship between self perceived food environment and fruit and vegetable intake in pregnant women. Objective: To evaluate the reliability of a self perceived questionnaerie about the food environment and for the consumption of fruit and vegetable in pregnant women (manuscript 1). To evaluate the relationship between self perceived food environment and the adequate consumption of fruits and vegetables in pregnant women (manuscript 2). Methods: The study was conducted in 2010 among 48 pregnant women attended by the public health service of Ribeirão Preto, SP. The questionnaire consists of 12 multiple choice questions which include the perception of the food environment and consumption of FV. To investigate the reproducibility of the questionnaire, it was administered twice, between 15 and 45 days apart. The agreement between the responses was assessed using the Kappa or Kappa weighted (manuscript 1). A cross-sectional study was conducted in 2012 among 282 adult pregnant women. Fruit and vegetable intake during pregnancy was assessed by a food frequency questionnaire, and 2 dietary recalls. The Multiple Source Method approach was applied to estimate usual FV intake. Self perceived food environment was assessed by a structured questionnaire. For the present analysis, we examined the association of self perceived food environment and the adequate intake of fruit and vegetable (400g/daily) in logistic regression models [OR (95% CI)], adjusted by maternal age, socioeconomic class, and educational level (manuscript 2). Results: Manuscript 1 describes the reliability of a self perceived questionnaire about the food environment and for the consumption of fruits and vegetables in pregnant women. There was strong agreement (Kappa: 0,6 to 0,79) for: meals per day, habit of eating at work, distance between the residence and places to purchase fruit and vegetable, quality of fruit and vegetable at the purchase place. Moderate agreement (Kappa 0,4 to 0,59): habit of eating out of home, habit of eating in self service restaurant, habit of eating in fast food restaurant, purchase food at grocery stores, convenience stores or bakery, variety of fruits and vegetables available and family support for healthy eating. Weak agreement (Kappa 0,2 to 0,39): habit of eating in friends or family house, purchase food at supermarket or FV specialized food market and perception of FV price. All the questions that had weak agreement were reformulated prior to use it. The manuscript 2 showed that 35% of the women intervied reported adequate intake of FV during pregnancy, with no association between self perceived food environment and adequate FV intake. However, a higher meal frequency was associated with a better chance of daily adequate intake of fruit and vegetable [OR 2.01 (95% CI 1.03, 3.91) p 0.04]. Moreover, the habit of buying fruit and vegetable in Abstract specialized food market was associated with the daily intake of 400g of fruit and vegetable [OR 1.68 (IC95% 1.01, 2.80) p 0.05]. Conclusion: The questionnaire of the perceived food environment and for the consumption of fruits and vegetables showed good precision among pregnant women. No association between self-perceived food environment and the adequate intake of FV among pregnant women was found.
19

A relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes / The relationship between self perceived food environment and fruit and vegetable intake by pregnant women.

Daniela Cristina Candelas Zuccolotto 14 June 2013 (has links)
Introdução: O consumo adequado de frutas, verduras e legumes (FVL) durante a gestação apresenta impacto positivo sobre a saúde da mulher e da criança. Os fatores ambientais associados ao comportamento alimentar vêm recebendo destaque no âmbito da saúde pública por afetar diretamente a saúde dos indivíduos. Entretanto, desconhecemos a existência de estudos que investigaram a relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes. Objetivo: Verificar a reprodutibilidade de um questionário sobre a percepção do ambiente alimentar e para o consumo de frutas e hortaliças em gestantes (manuscrito 1) e avaliar a relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes (manuscrito 2). Metodologia: O estudo de reprodutibilidade (manuscrito 1) foi conduzido em 2010 entre 48 gestantes usuárias do serviço público de saúde de Ribeirão Preto, SP. O questionário é composto por 12 questões de múltipla escolha que incluem a percepção do ambiente alimentar e para o consumo de frutas e hortaliças. Para verificação da reprodutibilidade, o questionário foi aplicado em duplicata, com intervalo entre 15 e 45 dias. A concordância entre as respostas foi avaliada por meio do teste de Kappa ponderado ou Kappa. A relação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças em gestantes (manuscrito 2) foi avaliada empregando-se os dados de um estudo transversal, conduzido em 2012, entre 282 gestantes adultas. O consumo de FVL foi avaliado por meio de um questionário de freqüência alimentar (QFA) , e dois recordatórios de 24 horas. O Multiple Source Method foi utilizado para estimar o consumo usual de FVL. A percepção do ambiente alimentar foi avaliada mediante a aplicação de questionário estruturado. Para a investigação da relação entre a as variáveis da percepção do ambiente alimentar e consumo adequado de FVL (400g/dia), modelos de regressão logística [OR (95% IC)] foram empregados ajustados por escolaridade, idade e classe econômica das gestantes. Resultados: No manuscrito 1, verificou-se a reprodutibilidade do questionário sobre a percepção do ambiente alimentar e para o consumo de frutas e hortaliças em gestantes. Concordância forte (Kappa entre 0,6 e 0,79) para: número de refeições ao dia, hábito de se alimentar no local de trabalho, distância entre a residência e local de aquisição de FVL e qualidade de FVL no local de aquisição. Concordância moderada (Kappa entre 0,4 e 0,59): hábito de se alimentar fora do domicílio, em restaurantes do tipo self-service ou por quilo, em lanchonetes, se adquire alimentos em mercearias, lojas de conveniência ou padaria, motivo da escolha do local para aquisição de FVL, variedade de FVL no local de aquisição e apoio familiar para ter uma alimentação saudável. Concordância fraca (Kappa entre 0,2-0,39): freqüência em que faz refeições na casa de amigos/ parentes, freqüência em que adquire alimentos em supermercados e varejão ou feira livre e percepção em relação ao preço de FVL. As questões que obtiveram concordância fraca foram reformuladas previamente a sua utilização. No manuscrito 2 observou-se que 35% das mulheres estudadas reportaram o Resumo consumo adequado de frutas e hortaliças durante a gestação, não encontrando uma associação direta entre a percepção do ambiente alimentar e o consumo adequado de frutas e hortaliças entre elas. Entretanto, as gestantes que relataram ter o hábito de fazer quatro ou mais refeições ao dia apresentaram maior chance de consumir a quantidade adequada de furtas e hortaliças quando comparadas àquelas que relataram menor número de refeições ao dia [OR 2.01 (95% IC 1.03, 3.91) p 0.04]. Da mesma forma, as mulheres que referiram o hábito de comprar FVL em varejão ou feira livre apresentaram maior chance de atingir a recomendação de frutas e hortaliças, independente de idade, escolaridade e classe socioeconômica [OR 1.68 (IC95% 1.01, 2.80) p 0.05]. Conclusão: O questionário sobre a percepção do ambiente alimentar e para o consumo de FVL apresentou boa precisão entre gestantes. Não houve associação entre a percepção do ambiente alimentar e o consumo de frutas e hortaliças entre as gestantes estudadas. / Introduction: The adequate intake of fruits and vegetables (FV) during pregnancy has a positive impact on the health of women and children. Environmental factors associated with eating behavior have received attention in the context of public health by directly affecting individuals health. However, unaware of the existence of studies that investigated the relationship between self perceived food environment and fruit and vegetable intake in pregnant women. Objective: To evaluate the reliability of a self perceived questionnaerie about the food environment and for the consumption of fruit and vegetable in pregnant women (manuscript 1). To evaluate the relationship between self perceived food environment and the adequate consumption of fruits and vegetables in pregnant women (manuscript 2). Methods: The study was conducted in 2010 among 48 pregnant women attended by the public health service of Ribeirão Preto, SP. The questionnaire consists of 12 multiple choice questions which include the perception of the food environment and consumption of FV. To investigate the reproducibility of the questionnaire, it was administered twice, between 15 and 45 days apart. The agreement between the responses was assessed using the Kappa or Kappa weighted (manuscript 1). A cross-sectional study was conducted in 2012 among 282 adult pregnant women. Fruit and vegetable intake during pregnancy was assessed by a food frequency questionnaire, and 2 dietary recalls. The Multiple Source Method approach was applied to estimate usual FV intake. Self perceived food environment was assessed by a structured questionnaire. For the present analysis, we examined the association of self perceived food environment and the adequate intake of fruit and vegetable (400g/daily) in logistic regression models [OR (95% CI)], adjusted by maternal age, socioeconomic class, and educational level (manuscript 2). Results: Manuscript 1 describes the reliability of a self perceived questionnaire about the food environment and for the consumption of fruits and vegetables in pregnant women. There was strong agreement (Kappa: 0,6 to 0,79) for: meals per day, habit of eating at work, distance between the residence and places to purchase fruit and vegetable, quality of fruit and vegetable at the purchase place. Moderate agreement (Kappa 0,4 to 0,59): habit of eating out of home, habit of eating in self service restaurant, habit of eating in fast food restaurant, purchase food at grocery stores, convenience stores or bakery, variety of fruits and vegetables available and family support for healthy eating. Weak agreement (Kappa 0,2 to 0,39): habit of eating in friends or family house, purchase food at supermarket or FV specialized food market and perception of FV price. All the questions that had weak agreement were reformulated prior to use it. The manuscript 2 showed that 35% of the women intervied reported adequate intake of FV during pregnancy, with no association between self perceived food environment and adequate FV intake. However, a higher meal frequency was associated with a better chance of daily adequate intake of fruit and vegetable [OR 2.01 (95% CI 1.03, 3.91) p 0.04]. Moreover, the habit of buying fruit and vegetable in Abstract specialized food market was associated with the daily intake of 400g of fruit and vegetable [OR 1.68 (IC95% 1.01, 2.80) p 0.05]. Conclusion: The questionnaire of the perceived food environment and for the consumption of fruits and vegetables showed good precision among pregnant women. No association between self-perceived food environment and the adequate intake of FV among pregnant women was found.
20

Produção de biogás a partir da co-digestão da fração orgânica dos resíduos sólidos urbanos e resíduos de hortifrutigranjeiros

Pavi, Suelen 19 August 2016 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-12-22T12:31:35Z No. of bitstreams: 1 Suelen Pavi_.pdf: 1636176 bytes, checksum: 0dd7b68d6b59964f41170ff034254b8d (MD5) / Made available in DSpace on 2016-12-22T12:31:35Z (GMT). No. of bitstreams: 1 Suelen Pavi_.pdf: 1636176 bytes, checksum: 0dd7b68d6b59964f41170ff034254b8d (MD5) Previous issue date: 2016-08-19 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / UNISINOS - Universidade do Vale do Rio dos Sinos / A digestão anaeróbia (DA) de resíduos é uma opção ambientalmente adequada para o tratamento de resíduos orgânicos e produção de biogás. Contudo, a eficiência do processo é influenciada por diversos fatores, incluindo a composição do substrato. Resíduos de hortifrutigranjeiros (RHF) apresentam propriedades físico-químicas adequadas para sua utilização como fonte energética. Porém, o alto teor de açúcares simples contido nas frutas e vegetais tende a acidificar o meio, inibindo a atividade dos microrganismos metanogênicos. A co-digestão com outros resíduos é uma alternativa para melhorar a estabilidade do processo. A fração orgânica dos resíduos sólidos urbanos (FORSU) também possui grande potencial energético que pode ser recuperado, e quando em co-digestão com RHF, a produção de biogás pode ser aumentada. Nesse contexto, o presente estudo buscou avaliar a produção de biogás a partir da co-digestão da FORSU com RHF, visando estabelecer uma proporção ótima onde a produção de biogás é máxima, sem danos à estabilidade do processo. O estudo foi realizado em quatro fases, em regime de batelada a 35 °C, empregando lodo anaeróbio como inóculo na relação S/I de 1/1 em termos de sólidos totais voláteis (STV). A massa de STV adicionada nos reatores foi a mesma em todas as condições. Foram testados a FORSU (Fase I) e os RHF (Fase IV) como mono-substrato e a co-digestão desses resíduos nas relações FORSU/RHF de 1/1 (Fase II) e de 1/3 (Fase III) em termos de STV. Os parâmetros monitorados foram pH, teor de sólidos totais e voláteis, carbono orgânico total, alcalinidade, ácidos graxos voláteis, ácidos orgânicos voláteis e volume de biogás. O biogás foi caracterizado quanto a teores de metano. Os resíduos aplicados na co-digestão e o biossólido final foram caracterizados quanto ao pH, teores de sólidos totais e voláteis, carbono orgânico total, alcalinidade, ácidos graxos voláteis, ácidos orgânicos voláteis, nitrogênio total e amoniacal e fósforo total. O processo de DA manteve-se estável em todas as condições de alimentação. Os resultados revelaram que a produção de biogás foi maior nas bateladas onde a FORSU e os RHF foram aplicados em co-digestão, em relação às bateladas que utilizaram FORSU e RHF como mono-substrato. A relação FORSU/RHF de 1/3 produziu o maior volume de biogás e obteve o maior rendimento de metano em função dos STV de resíduos aplicados, sendo 493,46 NL/kgSTV e 393,64 NL/kgSTV, respectivamente. / Anaerobic digestion (AD) of waste is an environmentally sound option for the treatment of organic waste and produce biogas. However, the process efficiency is influenced by several factors, including the composition of the substrate. Fruit and vegetable waste (FVW) have suitable physicochemical properties for use as an energy source. However, the high content of simple sugars contained in fruits and vegetables tend to acidify, inhibiting the activity of methanogens. The co-digestion of wastes is an alternative to improve process stability. The organic fraction of municipal solid waste (OFMSW) also has great energy potential that can be recovered, and when co-digestion with FVW, biogas production can be increased. In this context, this study aimed to evaluate the production of biogas from the co-digestion of OFMSW with FVW, to establish a great proportion where biogas production is maximum, without damage to the process stability. The study was conducted in four phases, batch system at 35 ° C, using anaerobic sludge as inoculum in the ratio S/I 1/1 in terms of the total volatile solids (VS). The VS mass added in the reactors was the same in all conditions. Were tested OFMSW (Phase I) and FVW (Phase IV) as mono- substrates and co-digestion of these wastes in relationships OFMSW/FVW 1/1 (Phase II) and 1/3 (Phase III) in terms of VS. The monitored parameters were pH, total and volatile solids, total organic carbon, alkalinity, volatile fatty acids, volatile organic acids and volume of biogas. Biogas was characterized as methane levels. Waste applied in co-digestion and the final biosolids were analyzed for pH, total and volatile solids content, total organic carbon, alkalinity, volatile fatty acids, volatile fatty acids, and total ammonia nitrogen and total phosphorus. The AD process remained stable in all power conditions. The results show that biogas production was higher in batches where OFMSW and FVW were applied by co-digestion in relation to batches that used OFMSW and FVW as mono-substrate. The relationship OFMSW/FVW of 1/3 produced the highest volume of biogas and obtained the higher yield of methane due to the VS applied to waste, being 493,46 NL/kgVS and 393,64 NL/kgVS respectively.

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