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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.
1

Food Security on Maui: Reinventing Agriculture in the Aloha State

Silver, Jade 01 April 2013 (has links)
This thesis focuses on the past, present, and future of food sustainability on Maui. It begins by explaining ancient Hawaiian agriculture and how this complex system of agriculture was deeply rooted in the customs and traditions of the Hawaiian people. The second section explores how this sustainable agricultural system changed after the arrival of Captain Cook in 1778. After western settlement, land that was once a communal resource became privatized. As land ownership shifted, the traditional subsistence agricultural system of Hawai’i began to change. Export crops such as sugar cane and pineapple became more widespread. As these crops shifted the way land was utilized in Hawai’i, the islands reduced the amount of crops grown for local consumption and became increasingly reliant on imported foods. The last section stresses the necessity of increasing the production of locally grown food on Maui. It discusses the locally grown food movement that has developed on Maui, and addresses the obstacles that prevent more food from being grown locally. Lastly, it suggests strategies to increase the amount of food produced for local consumption so that Maui can secure a more sustainable agricultural future.
2

The Foundations and Limitations of Public Information on Sustainability and Food Purchasing in Sweden

Alimohammad, Roohollah January 2015 (has links)
This thesis examines the nature and effects of current public information about food production, purchasing and sustainability that is available in Sweden. The thesis follows a two part structure based on the Action Research Cycle; it focuses predominantly on the initial diagnostic stage, using document review, questionnaires and Cultural Probes to examine what information is currently available to Swedish consumers, as well as how they respond to this information. The thesis then moves towards the action planning stage of the Action Research Cycle, using current academic literature in IS with the findings of my diagnostic research to suggest ways in which information-communication technology can be used to improve upon the current situation, and paving the way for future research in the area of public information and food sustainability.
3

DEVELOPMENT AND CHARACTERIZATION OF MICROBUBBLE BASED CLEAN IN PLACE FOR FOOD MANUFACTURING SYSTEM

Javier Estuardo Cruz Padilla (12660106) 17 June 2022 (has links)
<p> Fouling is one of the main problems in the food processing industry. The formation of fouling generates complications that could significantly impact the cost of production due to a reduction in heat transfer capacity or sanitation problems. Fouling formation inside enclosed systems can also lead to the growth of biofilms, causing food safety hazards. The fouling layers are firmly attached to the food contact surface of the equipment in ultra-high temperature (UHT) systems where a food product gets sterilized. Clean in place (CIP) is the most common process for cleaning and removal of fouling as it reduces cleaning time, chemicals, and water consumption compared to a regular cleaning out of place process. While cleaning and solids removal, microbubbles (MB) have shown improvement by enhancing the interaction of the components in the cleaning process with the source of contamination. Therefore, a novel pilot-scale microbubble-based CIP (MBCIP) technology was used for cleaning of fouled surfaces and compared to the traditional CIP process in terms of efficiency and reduction in water usage. The fouling layers attached to the food contact surface of the equipment in UHT was the main area examined. The research evaluated the fouling created at 110ºC in sections of stainless-steel pipes heated in a convection oven and at 121 ºC during regular processing in a UHT with coil heat exchangers system. Reconstituted Non-fat Dry Milk Powder (NFDM) was used as the primary source of protein to evaluate the cleaning efficiency. CIP factors were combined with temperatures at 21.11 ºC, 43.33 ºC, and 76.66 ºC, together with water, alkali, and acid, respectively. The optimal conditions for MBCIP were established and applied to a pilot-scale UHT system representative of a commercial-scale UHT system. The sequence of the CIP was water, alkali, water, acid, and water. The results showed that the acid solution at 76.66 ºC with microbubbles had a significantly higher protein removal compared to the rest of the evaluated conditions, removing 72% of the initial protein content compared to alkali and water which were 10 and <2.55%, respectively during 60 minute of CIP. During the full CIP with the combination of water, alkali, and acid, the effect of alkali was significantly higher than in the rest of the steps performed individually. With the addition of MB overall, CIP removed a considerable amount of protein (>21.5%) in a UHT system compared to the traditional CIP method within the 60 minutes period. CIP chemicals were the main factor contributing to the protein removal, and the gas content was the second most crucial factor in determining the removal. The addition of MB will have a meaningful impact when interacting with cleaning chemicals for industrial CIP. MB also occupies a very small amount of space inside the pipelines representing <0.05% of the volume fraction of the fluid inside the pipes, nevertheless, it can potentially reduce water consumption and provides a sustainable cleaning method for the food industry </p>
4

Sustainability in the Regional Food Supply Chain of Lahti

Snell, Johanna January 2017 (has links)
Unsustainable food production and consumption patterns are threatening our living environment and our lives on earth. There is a need for profound transition in our ways to produce and consume food. Food, its production and consumption is a hot topic currently – as can be seen in media and in several projects run by various institutions. Circular economy and sustainable resource management address different actors as well. The City of Lahti joined the FISU-network and is taking steps towards sustainable resource management. This thesis contributes to the ongoing work of the City of Lahti in developing its food sustainability strategic work through its participation in the FISU-network. The study aims to investigate the state of the regional food supply chain of Lahti, Finland, and its path on sustainability transition. Further on, it examines how alternative food networks may impact different aspects of sustainable local development and what kind of a role actors of regional food supply chain play in promoting food sustainability. This study applied a case study approach and used qualitative research methods in the forms of workshop and semi-structured interviews. The results were examined applying the theoretical framework which included Activity theory, Co-Creation and Economy of Common Good. There are various policies and strategies on global, national and regional level aiming to sustain the food system, food production and consumption, as well as promoting the use of local food. Few of them were used to reveal the present state of the regional food supply chain together with the results gained at the workshop and interviews to find the desired way. Alternative food networks may shorten the food supply chain and allow everyone a chance to contribute to local food sustainability. They may have social meaning by bringing the food supply chain actors together and offering more value than purchasing goods. Consumers can act as co-creators having possibility to influence what is produced, where and how. Alternative food networks may not necessarily be ecological, but they may have wider implications for the regional and local communities on economic, social and cultural levels by offering jobs, interaction, as well as giving a face and a story to the food.
5

Monique Chung Final Dissertation JYH MCv2.pdf

Monique Mi Song Chung (13943625) 08 December 2022 (has links)
<p>  </p> <p>Fouling is a severe problem for food processing equipment, including heat exchanger, filtration system, etc., which can decrease heat transfer efficiency, increase pressure drop, and affect food quality and safety. To ensure process efficiency and product quality, regular cleaning is necessary. On manufacturing lines in the food industry, cleaning is usually performed by cleaning-in-place (CIP) operations, which mainly comprise water rinse, alkaline wash and acid wash steps. Although CIP can ensure uniform cleaning of equipment, lower costs associated with labor and plant downtime, and improve personnel safety, it consumes large amounts of energy, chemicals and water and thus affects the environmental sustainability.</p> <p>Microbubbles (MBs) are fine gas bubbles with very different physicochemical properties from millimeter-sized bubbles, including longer residence time in liquid, higher mass transfer rate, larger surface-area-to-volume ratio, and generation of free radical when bubbles collapse. In addition, MBs feature hydrophobic liquid-gas interface, allowing hydrophobic and amphipathic substances to attach to and spread on bubble surfaces. MBs have been used in cleaning processes, such as oil flotation and fresh produce washing; however, their applications in CIP operations in food processing have not been explored.</p> <p>The objective of this dissertation is to develop a novel CIP operation with the incorporation of MBs for cleaning of food processing equipment. MBs were incorporated into rinsing water to clean milk deposit fouled on heat transfer surface. A computational fluid dynamics model was built to predict the contact frequency of MBs with deposit and further identify the flow conditions that provided maximum MB-deposit contact. Moreover, MBs were confirmed to be able to attach to milk deposit by microscopic imaging. Rinsing with MB-incorporated water noticeably enhanced the deposit removal at Re of 4392 and 5403, by 27−31%. For cleaning of microfiltration membrane reversibly fouled by palm oil-in-water emulsions as model wastewater, although adding MBs into alkaline wash increased the membrane flux recovery by 235%, increasing the crossflow velocity of MB-incorporated liquid did not guarantee the enhancement in cleaning performance. Lastly, a MB-assisted full CIP process was tested on an ultrafiltration system used for milk concentration. MB-assisted CIP showed an increased cleaning efficiency with up to 72% higher flux recovery than conventional CIP, and alkaline wash with MBs added was the major step accounting for enhanced protein removal.</p> <p>Overall, this dissertation proves the effectiveness of MBs in cleaning of different types of food deposits, and provides groundwork knowledge of MB incorporation into CIP operations for different food processing equipment. The results are expected to guide the scale-up of MB-assisted CIP processes that can reduce the water and chemical usage in food manufacturing sectors, ultimately improving both economic and environmental sustainability of the food industry.</p>
6

FUNCTIONAL PROPERTIES OF SOLUBLE HYDROCOLLOIDS EXTRACTED FROM <i>THEOBROMA BICOLOR</i><i> </i>(MACAMBO) PROCESSING WASTE AND IN-FIELD PRECOOLING UNITS TO REDUCE PRODUCE WASTE IN THE UNITED STATES

Rae Silver (15307708) 01 December 2023 (has links)
<p dir="ltr">Macambo (<i>Theobroma bicolor</i>) is a relative of cacao that was identified as an underutilized crop in San Martín, Peru with potential for valorization. Current processing for macambo seeds results in waste of two-thirds of the fruit, so the two waste streams (husk and pulp-shell) were characterized by proximal analysis to identify useable components. From the pulp-shell waste, soluble polysaccharides and proteins were extracted. The resulting hydrocolloid formed physical gels that had predominantly solid-like elastic behavior and can partially recover after being deformed by a constant stress. Macambo pulp-shell waste has potential for extracting functional ingredients for thickening, forming gels, retaining water, and stabilizing emulsions.</p><p dir="ltr">One third of food in the United States is never eaten, and waste occurs throughout the food system. Produce is a significant portion of food waste, but shelf life can be extended by optimizing postharvest practices. Conducting precooling in-field at point of harvest with mobile units was proposed by researchers in the field of food waste reduction as an adaptable method to reduce food waste and was evaluated in this study for innovation and barriers to use. Based on expert interviews and a literature review, it was concluded that in-field precooling units are hindered by infrastructure requirements and effective precooling is already optimized at large scale with centralized cooling activities. Flexible cooling technology could be part of a solution for very small growers in the United States and internationally in developing economies, where access to precooling and full cold chain is still lacking.</p>
7

An Eritrean Perspective of Africa's Potential for Indigenous, Independent Food Sustainability

Tesfagabir, Tewelde W. 01 January 2017 (has links)
Food insecurity in Africa is a threat to future generations because many countries rely on potentially unsustainable food policies. Eritrea's indigenous food sustainability policy has not been explored or analyzed in a scholarly manner. This qualitative case study analyzed the effectiveness of the current policy of food sustainability without relying on foreign food aid in Eritrea. The main research question addressed relates to how Eritrean irrigation farmers understand and implement the Eritrean government's food sustainability policy. The theoretical framework for this study, Kingdon's policy stream, set the agenda for a policy of sustainable indigenous Eritrean agricultural development without food aid. I have collected data by conducting semistructured interviews with 15 farmers who each have at least 7 years' experience providing food for their own families. Data from the interviews was audio recorded, transcribed, reviewed by the interviewees for increased credibility and reliability, translated in to English, and emergently coded and categorized for theme and pattern analysis. This study`s findings contain important lessons relative to advancing food self-sufficiency in Eritrea. The implications for social change across Africa may include informing practitioners and policymakers of the importance of applying appropriate policies to encourage food self-sufficiency.
8

The adoption of sustainable menu practices in healthcare institutions in Quebec : a study of feasibility

Dagenais, Béatrice 08 1900 (has links)
Problématique : La société québécoise affiche un intérêt marqué vers des systèmes alimentaires durables, visant à maintenir la santé humaine et de la planète par l’entremise des aliments nutritifs, tout en favorisant le développement économique et social. Dans cette perspective, les gestionnaires de services alimentaires d’établissements de santé peuvent privilégier des pratiques de menus durables (PMD). Peu de recherches existent sur les PMD dans ce contexte, et il s’avère donc important d’étudier leur faisabilité dans les établissements de santé québécois. Objectif : Cette étude vise à évaluer la faisabilité de l’adoption de PMD dans les services alimentaires des établissements de santé québécoises. Méthodologie : Suivant une approche d’application de connaissances intégrée et en partenariat avec le programme Nourrir la Santé (Fondation McConnell), une étude qualitative a été réalisée au moyen d’entretiens individuels semi-dirigés auprès de dix-sept gestionnaires de services alimentaires, recrutés par échantillonnage intentionnel dans dix des trente établissements de santé du Québec. La théorie révisée de la diffusion des innovations, décrivant les neuf déterminants principaux liés aux processus de diffusion d’une innovation (les PMD) dans un système social complexe (les organisations de santé), a structuré la collecte et l’analyse des données. Résultats : Les gestionnaires rapportent être motivés par les PMD. Toutefois, la mise en oeuvre d’actions concrètes s’avère difficile par manque de priorisation organisationnelle. Les défis, plus nombreux que les éléments facilitateurs, incluent la complexité perçue des PMD, le contexte du système de santé, le manque considérable de ressources et l’absence de politiques claires du Ministère de la Santé. Pour une meilleure adoption des PMD, les gestionnaires de services alimentaires ont besoin d’un soutien organisationnel accru, des directives ministérielles claires et plus de collaboration entre tous les acteurs du système alimentaire. Discussion : Cette recherche contribue à une compréhension approfondie de l’expérience de gestion en matière d’adoption de PMD dans divers contextes régionaux et institutionnels. Les résultats suggèrent un besoin de création de partenariats, ainsi que du soutien et des stratégies pouvant éliminer les barrières principales à l’adoption de PMD. / Background: In many societies, as in Quebec, there is an increased interest towards sustainable food systems. Food sustainability aims to maintain human and planetary health through nutritious food, all the while promoting economic and social development. In this perspective, foodservice managers in healthcare institutions can prioritize sustainable menu practices (SMPs). As there is little research on SMPs in this context, it is of uttermost importance to understand their feasibility in healthcare institutions. Objective: This study aimed to analyze the feasibility of adopting SMPs in Quebec healthcare institutions. Methods: Following an integrated knowledge translation and exchange approach and in partnership with Nourish (McConnell Foundation), a qualitative study was carried out using semi-structured interviews with seventeen foodservice managers, recruited through purposeful sampling in ten of thirty healthcare institutions in Quebec. The revised Diffusion of innovations theory, describing the nine principal determinants of the processes of the diffusion of an innovation (SMPs) in a complex social system (healthcare organization), structured the interview guide for data collection and the codebook for data analysis. Results: Managers report being motivated by food sustainability, however this does not always translate to concrete actions due to its lack of prioritization in foodservices. Challenges to adopt and implement SMPs are considerably more recurrent than facilitators. Key barriers include perceived SMP complexity, the context of the healthcare system, a substantial lack of resources and shortfalls in clear political directives from Ministry of Health. Amongst enhanced support and ministry guidance, foodservice managers need increased collaboration between all food system actors for better SMP adoption. Discussion: This research contributes to in-depth understanding of the managerial experience in SMP adoption in various regional and institutional settings. Findings suggest the need for food system partnerships, as well as support and strategies that would remove important barriers in SMP adoption.
9

Novel Microplastics Remediation Strategy Using High-Voltage Atmospheric Cold Plasma

Juan Velasquez (15353575) 27 April 2023 (has links)
<p>  </p> <p>Plastics are the most common polymers used in various industries. However, million tons of plastics are produced and disposed every year around the world, and part of them end up entering the environment and agricultural ecosystems in the form of microplastics. Microplastics have become an environmental and health threat to aquatic species and humans because they are small and can easily reach water bodies for municipal and agricultural uses. Microplastics have been traced in food commodities and products derived from animals and even found in bottles of drinking water. As an approach to permanently remediating microplastics, current microplastic degradation techniques, however, require high energy inputs and thus are generally not cost-efficient. High-voltage atmospheric cold plasma (HVACP) is a low-cost energy-efficient technology to produce highly reactive species that can induce physicochemical changes in polymers. This study, for the first time, used HVACP as a novel remediation strategy for microplastics. HVACP was generated by dielectric barrier discharge at 50 kV using oxygen, nitrogen, or their mixture as working gas. Two types of microplastics, polypropylene (PP) and low-density polyethylene (LDPE), were treated for 30 min, and the effect of 24-h post-treatment was also studied. The properties of HVACP-treated microplastics, including weight, particle size, crystallinity, melting point, carbonyl index (CI), and surface morphology, were comprehensively analyzed. HVACP treatments were found effective in degrading both PP and LDPE microplastics. A larger extent of degradation was observed with PP microplastics treated by O/N mixture plasma, but the nitrogen plasma-treated sample showed a higher degree of oxidation according to its CI. For PE microplastics, oxygen plasma caused more degradation, but post-treatment did not promote further oxidation. The results indicated two potential mechanisms for microplastic degradation by HVACP. LDPE microplastics were degraded by oxidative reactions caused by highly reactive oxygen species, and PP microplastics followed a hydrolytic pathway of degradation as they became more hydrophilic after HVACP treatment. This study proved that HVACP is a promising method for microplastic degradation, and thus has great potential for addressing the severe challenges of microplastics that the food and agriculture sectors are currently facing.</p>
10

Life Cycle Assessment for Improving Sustainability of Aquaculture and Aquaponics

April Janai Arbour (17583837) 09 December 2023 (has links)
<p dir="ltr">Controlled environment agriculture (CEA) is a practice of food production under optimized conditions to intensify production yield, and thus has potential for addressing food security for a growing population. Aquaculture and aquaponics are two types of CEA that can produce aquatic animals along with plants using non-arable lands and lower inputs of water and nutrients. However, their operations have high energy consumption and generate considerable nutrient-rich sludge and wastewater, making their environmental performance an emerging research focus. This thesis quantitively analyzed the environmental sustainability of aquaponics and aquaculture production using life cycle assessment (LCA).</p><p dir="ltr">The LCA on aquaponics evaluated a marine aquaponics production system that grew shrimp, red orache, minutina and okahajiki, and analyzed the effect of salinity, C/N ratio, and shrimp-to-plant stocking density. The grow-out stage accounted for over 90% of total environmental impacts with electricity use as the predominant contributor. The marine aquaponic production exhibited best environmental performance when operated at low salinity (10 ppt), and high C/N ratio (15) and stocking density (5:1), which can be further improved by 95–99% via the use of wind power as electricity source. Additionally, variation in the prices of aquaponic products was found to improve the system’s environmental impacts by up to 8%.</p><p dir="ltr">The aquaculture LCA focused on shrimp recirculating aquaculture systems (RAS) and evaluated the environmental feasibility of microalgae-based wastewater treatment. Microalgae treatment effectively removed 74% of phosphate in RAS wastewater and thus reduced the freshwater eutrophication potential by 55%. However, its remediation performance was inferior to activated sludge treatment due to different operation scales. Electricity was the principal hotspot of microalgae treatment and made up over 99% of all the environmental impacts, which can be considerably decreased by reducing coal use in the electricity supply. Three utilization pathways for algal biomass (feed ingredient, biodiesel and biogas) were investigated; however, only biogas production was found to show environmental benefits to marine eutrophication remediation owing to the low biomass quantity produced.</p><p dir="ltr">While <a href="" target="_blank">aquaculture and aquaponics</a> play important roles in meeting the globally growing demand for seafood, this thesis provides valuable life cycle inventory data for these fields. Moreover, the LCA models developed in this thesis are useful decision-making tools for aquaculture and aquaponic producers to adapt farming practices with lower environmental footprint.</p>

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