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INVESTIGATING GERMINATING SEEDS AS OXYGEN SCAVENGERS IN HERMETIC STORAGE: IMPLICATIONS FOR INSECT MORTALITYGunakeshari Lamsal (16642938) 01 August 2023 (has links)
<p>Hermetic storage systems have gained global popularity for their ability to minimize stored product losses by depleting oxygen. However, relying solely on insects to deplete oxygen in hermetic storage, when this process takes longer, can result in (further) damage to stored commodities. This study was conducted to investigate: (i) the potential of four different germinating seeds (soybean, rice, cowpea, and corn) in scavenging oxygen within hermetic storage systems; (ii) the impact of container volume and the number of germinating seeds on oxygen depletion; and (iii) the effects of germinating seeds on insect mortality and grain quality. Among the crops tested, cowpea, during their fourth, fifth, and sixth germination stages (T4, T5, and T6), depleted oxygen below 5% within 12 hours. The fourth stage of cowpea (T4) was identified as a potential oxygen scavenger due to its shorter germination time and ease of handling. Moreover, increasing the number of germinating seeds resulted in a faster initial rate of oxygen depletion in all-sized jars. Doubling both the volume of the jars and the number of germinating seeds had a similar rate of oxygen depletion. Additionally, an equation was derived to predict the required number of germinating seeds based on data from different numbers of seed and container volume combinations. Relative humidity levels increased to approximately 90% when empty jars were used but remained consistent at 40% when the jars were filled with grains. Furthermore, using 10, 20, and 30 germinating cowpea seeds with stored grains and insects, oxygen levels were reduced below 5% at different time intervals. Complete adult mortality of <em>C. maculatus</em> was achieved within 3-5 days of exposure, depending upon the number of germinating seeds. 20 and 30 seeds achieved complete mortality within 72 hours, while 10 seeds required 120 hours. As the number of germinating seeds increased, egg counts decreased, and moisture content significantly increased in the treatment involving 30 seeds. Furthermore, no adult emerged after 96 and 120 hours of exposure to normoxia for the 30 and 20 seed treatments, respectively. However, in the 10 seeds treatment, a small percentage of adults (0.29%) did emerge even after 120 hours of exposure.</p>
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Effects of Storage Conditions of Aspergillus Growth and Aflatoxin Production in Peanuts. A Study in GhanaDarko, Clara Bernice 13 February 2017 (has links)
Peanuts (Arachis-hypogaea) are one of the staples in Ghana, Sub-Saharan Africa, and other developing countries. This leguminous crop is frequently contaminated with aflatoxins, which are secondary metabolites of some Aspergillus fungi, mostly Aspergillus. flavus and Aspergillus parasiticus. Aflatoxins in foods are known to cause liver cancer, stunted growth in children, immune system disorders and economic losses. Aflatoxin contamination of peanuts during storage is worse in the tropics because climatic storage conditions there are almost the same as the optimum conditions for Aspergillus growth: temperature conditions of about 26-43 °C and relative humidity of 62-99%. This study investigated the growth of Aspergillus and the production of aflatoxin in shelled peanuts under varying treatment and packaging conditions. In addition, the appropriate pre-storage treatments and packaging needed to reduce aflatoxin production and to maintain quality of shelled and in-shell peanuts in storage under tropical environments were studied. Another aim was to determine the impact of the switch to hermetic storage on peanut farming and marketing profitability in Ghana.
Different peanut treatments, with and without Aspergillus flavus fungi, were packaged in different systems; specifically, polypropylene woven sacks and hermetic packaging. Peanuts were analyzed for fungi growth, aflatoxin production and lipid oxidation (peroxide value and p-Anisidine value).
Partial roasting and blanching of peanuts eliminated aflatoxigenic fungi and halted aflatoxin production in stored peanuts, increased the effectiveness of peanut sorting and, hence, helped reduce or eliminate aflatoxin levels along the peanut value chain. Additionally, the results of this study demonstrated that hermetic storage, by suppressing aflatoxin production, has the potential for maintaining peanut quality vis a vis polypropylene woven packaging. Profitability analysis conducted as part of this study revealed that the use of the hermetic storage system would not only improve farmer and trader profits, but also reduce the incidence of various ailments attributed to aflatoxins. / Ph. D.
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<b>Accelerating oxygen depletion in hermetic storage using hand warmers to improve pest control</b>Wenbo Li (19337320) 06 August 2024 (has links)
<p dir="ltr">This study explores the use of hand warmers to enhance hermetic storage. Hand warmers work similarly to conventional oxygen scavengers by consuming oxygen through oxidation. This research aimed to determine how effective hand warmers are in accelerating oxygen reduction and insect mortality in hermetic storage, hence preserving grain quality. The experiments conducted in hermetic containers showed that hand warmers rapidly reduce oxygen levels, achieving insect-lethal conditions much faster than conventional oxygen absorbers like Oxy-Sorb. Our results show that hand warmers brought oxygen levels down to below 5% within 24-48 h and kept them low for an extended period up to 240 h. This quick oxygen depletion led to high insect mortality, reduced oviposition, and inhibited progeny development. Additionally, hand warmers did not negatively impact seed moisture content or germination rates, demonstrating their effectiveness in maintaining grain quality during storage.</p>
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Qualidade de Grãos de Feijão Armazenados sob Atmosfera Modificada / Quality of beans stored under modified atmosphereFreitas, Romenique da Silva de 18 March 2009 (has links)
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Previous issue date: 2009-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study was conducted at the Experimental Farm Rafael Fernandes, Mossoró city, Rio Grande do Norte State, Brazil, with the objective to verify the effect of irrigation levels and planting densities on the castor bean production, BRS ENERGIA . Thus, we used the experimental design in randomized blocks in a split-plot 5 x 2, with four replications. The treatments consisted of irrigation levels (0.6, 0.8, 1.0, 1.2 and 1.4 of ETc) in main plots and plant densities in the sub-plots formed by arrangements 1.50 m x 0.30 m x 0.30 m (D1 - 37,037 plants ha-1) and 1.50 m x 0.30 m x 0.40 m (D2 - 27,778 plants ha-1). The main plots were 18 m in length, 9 m for each of the densities. The irrigation levels were differentiated by the application time using the tubes, each of which had a strip of the water distribution system independent. The main bunches fruits income decreased with the applied levels and the secondary bunches income (in fruits and grains) followed quadratic polynomial model. How much to the total income, was gotten 3,974 kg ha-1 of fruits and 2,691 kg ha-1 of grains with irrigation based on 1,20 and 1,25 of the etc, respectively. / FREITAS, Romenique da Silva. Qualidade de grãos de feijão armazenados sob atmosfera modificada. Mossoró, UFERSA, 2009. 62 f. Dissertação (Mestrado em Agronomia: Fitotecnia) Universidade Federal Rural do Semi-Árido (UFERSA), Mossoró-RN, 2009. Professor Orientador: D. Sc. Patrício Borges Maracajá. Co- orientador: Profa. D. Sc. Lêda Rita D Antonino Faroni. Conselheiros: Prof. D. Sc. Glauber Henrique de Sousa Nunes e Profa. D. Sc. Danila Kelly Pereira Neri.
Este trabalho teve por objetivo avaliar a qualidade de grãos de feijão com diferentes teores de água, armazenados em condições herméticas, ao longo do armazenamento. O experimento foi realizado no Setor de Pré-Processamento e Armazenamento de Produtos Agrícolas do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa (UFV). Foram utilizados grãos de feijão (Phaseolus vulgaris L.) do grupo vermelho, cultivar vermelhinho, com teores de água de 12,3, 15,7 e 17,8% b.u., produzidos na safra de inverno (2008), no município de Viçosa-MG. Os grãos foram acondicionados em embalagens herméticas e armazenados em câmara climática, por 0, 30, 60, 90 e 120 dias, à temperatura de 25 °C e umidade relativa de 70±5%. No armazenamento foram utilizadas bolsas plásticas, impermeáveis com capacidade para três quilogramas e garrafas pet transparente com capacidade para 1,5 L. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial com parcelas subdivididas e três repetições, sendo as parcelas representadas pelo fatorial condição de armazenamento (silo tipo bolsa, garrafa pet e testemunha) e teor de água do grão (12,3, 15,7 e 17,8% b.u.) e as subparcelas representadas pelos períodos de armazenamento (0, 30, 60, 90 e 120 dias). Avaliou-se o teor de água, grau de infestação por insetos-praga, massa específica aparente, condutividade elétrica, percentual de germinação, tempo de cocção e classificação dos grãos, após cada período de armazenamento. Todas as variáveis analisadas variaram significativamente (p<0,05) entre os teores de umidade, condições (hermética/não
hermética) e períodos de armazenamento. Grãos de feijão com teores de água de 12,3 e 15,7% b.u., armazenados em condições herméticas, mantiveram as características analisadas por 120 dias, exceto o tempo de cocção. Grãos de feijão com teores de água de 17,8% b.u., armazenados em condições herméticas, mantiveram as características analisadas por um período de 60 dias, exceto o tempo de cocção. A perda de qualidade, caracterizada pelo aumento no tempo de cocção, foi maior nos grãos com maior teor de água, armazenados em condições herméticas. Nos grãos com menor teor de água o tempo de cocção foi mantido por 90 dias. O armazenamento hermético é capaz de manter a qualidade de grãos de feijão com teores de água variando de 12,3 a 15,7% b.u. por 120 dias.
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Qualidade de Grãos de Feijão Armazenados sob Atmosfera Modificada / Quality of beans stored under modified atmosphereFreitas, Romenique da Silva de 18 March 2009 (has links)
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Previous issue date: 2009-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study was conducted at the Experimental Farm Rafael Fernandes, Mossoró city, Rio Grande do Norte State, Brazil, with the objective to verify the effect of irrigation levels and planting densities on the castor bean production, BRS ENERGIA . Thus, we used the experimental design in randomized blocks in a split-plot 5 x 2, with four replications. The treatments consisted of irrigation levels (0.6, 0.8, 1.0, 1.2 and 1.4 of ETc) in main plots and plant densities in the sub-plots formed by arrangements 1.50 m x 0.30 m x 0.30 m (D1 - 37,037 plants ha-1) and 1.50 m x 0.30 m x 0.40 m (D2 - 27,778 plants ha-1). The main plots were 18 m in length, 9 m for each of the densities. The irrigation levels were differentiated by the application time using the tubes, each of which had a strip of the water distribution system independent. The main bunches fruits income decreased with the applied levels and the secondary bunches income (in fruits and grains) followed quadratic polynomial model. How much to the total income, was gotten 3,974 kg ha-1 of fruits and 2,691 kg ha-1 of grains with irrigation based on 1,20 and 1,25 of the etc, respectively. / FREITAS, Romenique da Silva. Qualidade de grãos de feijão armazenados sob atmosfera modificada. Mossoró, UFERSA, 2009. 62 f. Dissertação (Mestrado em Agronomia: Fitotecnia) Universidade Federal Rural do Semi-Árido (UFERSA), Mossoró-RN, 2009. Professor Orientador: D. Sc. Patrício Borges Maracajá. Co- orientador: Profa. D. Sc. Lêda Rita D Antonino Faroni. Conselheiros: Prof. D. Sc. Glauber Henrique de Sousa Nunes e Profa. D. Sc. Danila Kelly Pereira Neri.
Este trabalho teve por objetivo avaliar a qualidade de grãos de feijão com diferentes teores de água, armazenados em condições herméticas, ao longo do armazenamento. O experimento foi realizado no Setor de Pré-Processamento e Armazenamento de Produtos Agrícolas do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa (UFV). Foram utilizados grãos de feijão (Phaseolus vulgaris L.) do grupo vermelho, cultivar vermelhinho, com teores de água de 12,3, 15,7 e 17,8% b.u., produzidos na safra de inverno (2008), no município de Viçosa-MG. Os grãos foram acondicionados em embalagens herméticas e armazenados em câmara climática, por 0, 30, 60, 90 e 120 dias, à temperatura de 25 °C e umidade relativa de 70±5%. No armazenamento foram utilizadas bolsas plásticas, impermeáveis com capacidade para três quilogramas e garrafas pet transparente com capacidade para 1,5 L. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial com parcelas subdivididas e três repetições, sendo as parcelas representadas pelo fatorial condição de armazenamento (silo tipo bolsa, garrafa pet e testemunha) e teor de água do grão (12,3, 15,7 e 17,8% b.u.) e as subparcelas representadas pelos períodos de armazenamento (0, 30, 60, 90 e 120 dias). Avaliou-se o teor de água, grau de infestação por insetos-praga, massa específica aparente, condutividade elétrica, percentual de germinação, tempo de cocção e classificação dos grãos, após cada período de armazenamento. Todas as variáveis analisadas variaram significativamente (p<0,05) entre os teores de umidade, condições (hermética/não
hermética) e períodos de armazenamento. Grãos de feijão com teores de água de 12,3 e 15,7% b.u., armazenados em condições herméticas, mantiveram as características analisadas por 120 dias, exceto o tempo de cocção. Grãos de feijão com teores de água de 17,8% b.u., armazenados em condições herméticas, mantiveram as características analisadas por um período de 60 dias, exceto o tempo de cocção. A perda de qualidade, caracterizada pelo aumento no tempo de cocção, foi maior nos grãos com maior teor de água, armazenados em condições herméticas. Nos grãos com menor teor de água o tempo de cocção foi mantido por 90 dias. O armazenamento hermético é capaz de manter a qualidade de grãos de feijão com teores de água variando de 12,3 a 15,7% b.u. por 120 dias.
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Constantes de viabilidade para sementes de feijoeiro dos cultivares Tibatã e Una / Viability equation constants for two Phaseolus vulgaris cultivarsFrancisco, Fabiana Gonçalves 17 February 2006 (has links)
Orientador: Roberto Usberti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-06T12:54:09Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: O conhecimento do comportamento das sementes em relação às condições de armazenamento a que são submetidas é de extrema importância para a avaliação de sua armazenabilidade. Este experimento analisou o armazenamento de sementes de Phaseolus vulgaris visando a obtenção das constantes da equação de viabilidade para dois cultivares, para a sua conservação e para garantir a sua disponibilidade. As sementes de feijoeiro foram reidratadas com água e/ou secas em sílica gel, ambas a 25°C, a partir dos seus valores iniciais até a obtenção dos valores de umidade desejados. Amostras de sementes com graus de umidade para os cultivares Tibatã e Una (3,28 a 16,65 e 3,14 a 17,26, com valores iniciais de 13,61 e 12,35%, respectivamente) foram acondicionadas em embalagens de alumínio termo soldadas e armazenadas a 40, 50 e 65°C até a obtenção de curvas completas de deterioração. As análises estatísticas foram realizadas pelo programa ¿Glim¿. Dois grupos de constantes foram obtidos para prever a longevidade de sementes dos cultivares Tibatã e Una, a saber: KE = 5,759; 4,556; CW = 4,598; 5,209; CH =0,0451; 0,1213; CQ = 0,001014; 0,001764, respectivamente. Foi observada uma relação inversa entre o grau de umidade e a longevidade das sementes. O limite inferior calculado para aplicação da equação para os dois cultivares de Phaseolus vulgaris a 65°C situa-se ao redor de 4,52 e 6,15% para Tibatã e Una, respectivamente em equilíbrio com valores de UR ao redor de 20% / Abstract: The previous knowledge of seed performance during storage is important to evaluate its storability. This experiment analysed Phaseolus vulgaris seed storage aiming to get viability equation constants for two cultivars, as to guarantee seed disposal and conservation. Seeds were rehydrated over water or dried over silica gel, both at 25°C, from the initial moisture contents, until achieved desired mc values. Seed samples with mc ranging from 3.28 to 16.65 and 3.14 to 17.26 (Tibatã and Una), with initial mc of 13.61 and 12.35%, respectively, were then placed in aluminium foil packets and stored at 40, 50 e 65°C until obtaining complete survival curves. Statistical analysis was performed through Glim software. Two different groups of constants were calculated as to predict seed longevity of Tibatã and Una cultivar, as follows: KE = 5.759; 4.556; CW = 4.598; 5.209; CH =0.0451; 0.1213; CQ = 0.001014; 0.001764, respectively. An inverse relationship was observed between moisture content and seed longevity. The lower limit for viability equation application at 65°C for the cultivars Tibatã and Una were 4.52 and 6.15%, respectively, on equilibrium with RH around 20% / Doutorado / Tecnologia Pós-Colheita / Doutor em Engenharia Agrícola
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After the Project is Over: Measuring Longer-Term Impacts of a Food Safety Intervention in SenegalLaura Elizabeth Leavens (9183350) 30 July 2020 (has links)
<p>We followed up with about 2,000 smallholder households in Senegal, two years after these households participated in a randomized controlled trial (RCT) aimed at reducing levels of aflatoxins in smallholders’ stored maize. In the initial intervention, treated households were provided with training on proper post-harvest practices, low-cost moisture meters for testing if maize was sufficiently dry to store, plastic tarps for drying maize of the ground, and hermetic (airtight) storage bags to mitigate aflatoxin development in stored maize. Using cross-sectional follow up data on aflatoxins levels and drying and storage practices from 2019 along with baseline demographic data from 2016, we estimate both the longer-term intention-to-treat (ITT) effects and the treatment on the treated (TOT) effects that the four inputs provided on households’ aflatoxins levels in stored maize. The ITT analyses estimate the intervention’s average effect by treatment group, but this may underestimate the true impact for households who complied with recommended post-harvest practices and adopted the recommended technologies. The TOT analyses estimate the local average treatment effects (LATE) of the intervention, that is its impacts on those who were driven by the intervention to follow best practices or use a given technology. Since the decision to follow these practices or adopt a technology was not random, we instrumented the usage decision with the exogenous, random treatment group assignment to get an unbiased estimate. Outside of our main models, we conducted a heterogeneity analysis to test if households with different characteristics benefit differently from the intervention. We interacted each treatment assignment with various household characteristics, including the woman’s level of involvement in the intervention. Additionally, we estimate the cost-effectiveness of providing training and a tarp, according to WHO guidelines for public health interventions. </p>
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