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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.
61

Using Computer Vision to Build a Predictive Model of Fruit Shelf-Life

Thor, Nandan G 01 June 2017 (has links) (PDF)
Computer vision is becoming a ubiquitous technology in many industries on account of its speed, accuracy, and long-term cost efficacy. The ability of a computer vision system to quickly and efficiently make quality decisions has made computer vision a popular technology on inspection lines. However, few companies in the agriculture industry use computer vision because of the non-uniformity of sellable produce. The small number of agriculture companies that do utilize computer vision use it to extract features for size sorting or for a binary grading system: if the piece of fruit has a certain color, certain shape, and certain size, then it passes and is sold. If any of the above criteria are not met, then the fruit is discarded. This is a highly wasteful and relatively subjective process. This thesis proposes a process to undergo to use computer vision techniques to extract features of fruit and build a model to predict shelf-life based on the extracted features. Fundamentally, the existing agricultural processes that do use computer vision base their distribution decisions on current produce characteristics. The process proposed in this thesis uses current characteristics to predict future characteristics, which leads to more informed distribution decisions. By modeling future characteristics, the process proposed will allow fruit characterized as “unfit to sell” by existing standards to still be utilized (i.e. if the fruit is too ripe to ship across the country, it can still be sold locally) which decreases food waste and increases profit. The process described also removes the subjectivity present in current fruit grading systems. Further, better informed distribution decisions will save money in storage costs and excess inventory. The proposed process consists of discrete steps to follow. The first step is to choose a fruit of interest to model. Then, the first of two experiments is performed. Sugar content of a large sample of fruit are destructively measured (using a refractometer) to correlate sugar content to a color range. This step is necessary to determine the end-point of data collection because stages of ripeness are fundamentally subjective. The literature is consulted to determine “ripe” sugar content of the fruit and the first experiment is undertaken to correlate a color range that corresponds to the “ripe” sugar content. This feature range serves as the end-point of the second experiment. The second experiment is large-scale data collection of the fruit of interest, with features being recorded every day, until the fruit reaches end-of-life as determined by the first experiment. Then, computer vision is used to perform feature extraction and features are recorded over each sample fruit’s lifetime. The recorded data is then analyzed with regression and other techniques to build a model of the fruit’s shelf-life. The model is finally validated. This thesis uses bananas as a proof of concept of the proposed process.
62

The Hidden Contribution of Food Literacy to Food Waste Reduction / 食品ロス削減に関わるフードリテラシーの隠れた貢献に関する研究

Nomura, Ayaka 23 September 2020 (has links)
学位プログラム名: 京都大学大学院思修館 / 京都大学 / 0048 / 新制・課程博士 / 博士(総合学術) / 甲第22813号 / 総総博第15号 / 新制||総総||2(附属図書館) / 京都大学大学院総合生存学館総合生存学専攻 / (主査)教授 池田 裕一, 教授 山敷 庸亮, 特定講師 Hart Nadav FEUER / 学位規則第4条第1項該当 / Doctor of Philosophy / Kyoto University / DFAM
63

Anaerobic Co-Digestion of Food waste and Primary Sludge

Chari, Pooja Surendra 15 June 2017 (has links)
No description available.
64

Physical Treatments To Modify The Functionality Of Carrot Pomace And The Development Of An Enhanced Beef Patty

Richards, Jordan O.A 01 September 2023 (has links) (PDF)
Approximately one-third of the global food produced for human consumption is lost or wasted somewhere along the food chain. Carrots are one of the most important and widely produced root vegetables grown worldwide; they are rich in many beneficial bioactive compounds such as dietary fiber and carotenoids. Every year, an estimated 29% of processed carrots are lost as waste. The U.S. is the 3rd largest producer of carrots worldwide, 85% of which come from California. During carrot juice processing, up to 50% of the raw material remains as carrot pomace. Carrot pomace may contain up to 55% total dietary fiber, which is thought to have important functional properties such as water holding and fat binding. The objectives of this project were to: 1) Investigate how physical pretreatment and drying treatment affect the functional and chemical properties of carrot pomace, 2) evaluate the impact that carrot pomace as a functional ingredient will have on the physical and chemical properties of beef patties, and 3) validate the developed beef patties using a consumer sensory test to ensure that the products have acceptable sensory attributes. High shearing and hydraulic pressing pretreatments (HSHP) increased the swelling capacity of freeze-dried carrot pomace by 59% and dehydrated carrot pomace by 34%. Freeze-dried carrot pomace also retained 33% more carotenoids compared to dehydrated pomace. The drying method significantly impacted the functional properties of carrot pomace. Freeze drying improved the water holding capacity by 22% and fat binding capacity by 194% over dehydrated carrot pomace. The addition of dried carrot pomace increased the cooking yield and water-holding capacity of beef patties by 5-15% and 12%, respectively, without significantly changing their textural properties or chemical composition. Eighty-six (86) consumers took part in sensory testing to evaluate beef patties formulated with carrot pomace. Overall, there were no significant differences in liking scores between the carrot pomace patties at 1% & 3% and the control patty. Scores were not changed significantly when patties were consumed with a bun. These results suggested that carrot pomaces may be physically modified to be utilized as a functional ingredient in the food industry.
65

Optimization Approaches for Modeling Sustainable Food Waste Management Systems

Kuruppuarachchi, Lakshika Nishadhi 15 September 2022 (has links)
No description available.
66

Unlocking the Potential of Carbonaceous Resource Recovery from the Arrested Anaerobic Digestion of Food Waste: Engineering Design and Meta-omics Analysis

Jiang, Minxi January 2022 (has links)
Organic waste-fueled carbonaceous resource recovery using approaches such as arrested anaerobic digestion generates economically attractive products such as volatile fatty acid (VFA). The production of VFA expands the applications of anaerobic biotechnologies beyond the traditionally produced biogas. Compared to biogas, VFA is produced and recovered in a concentrated form in the aqueous phase, which is more conducive to direct utilization in downstream bioplastic, biodiesel production, and nitrogen/phosphorus removal in water resource-recovery facilities. However, this application is limited by the variability in VFA yield and composition as obtained from different complex solids streams. Additionally, the lack of understanding of the nexus between the performance-structure-function of the microbial community within the arrested anaerobic digestion process leads to the massive gap between the optimized engineering regulations and the high-throughput VFA production. Consequently, this dissertation aimed to unlock the potential of VFA production with maximized yield and regulated composition through the manipulation of the operational parameter (hydraulic retention time (HRT)) and the feedstock condition (thermal hydrolysis pretreatment (THP)). In response, meta-omics-derived approaches were applied to elucidate the dynamic changes of microbial structure, potential, and extant functionality in terms of the two processes (hydrolysis and acidification) within arrested anaerobic digestion of food waste. Specifically, the objectives were (1) Performance: Evaluate the hydrolysis and acidification performance changes including hydrolysis yield, VFA yield, VFA composition, methane yield, etc. under different HRTs and feeding THP or non-THP food waste. (2) Microbial structure: characterize and compare the significance of HRT and feedstock condition in shaping microbial structures. (3) Functional analysis: Interpret the community-level dynamic changes of potential and extant functions within the (3.1) customized acidification metabolic networks and the (3.2) carbohydrate hydrolysis niches. The highlighted findings are as follows: (1) Performance of the arrested anaerobic digestion (including hydrolysis and acidification processes): Neither the hydrolysis yield nor the VFA yield was improved by the extended HRT from 4 to 8 days (P > .05). The inclusion of THP on feedstock didn’t improve the hydrolysis yield (P > .05) while the VFA yield was significantly decreased (P = .003). Among all conditions, the methane production was less than 5% of the chemical oxygen demand (COD) and a propionic acid-dominant type product was robustly formed. (2) Microbial structures in the arrested anaerobic digestors (including core hydrolyzers and acidification microbial communities): Both HRT and the inclusion of THP on feedstock shaped distinct microbial structures in the arrested anaerobic digestors (P = .02 and .01). Although the extension of HRT didn’t change the Shannon diversity Index (P > .05), it was significantly decreased after feeding with THP food waste (P = .03), which might stem from the reduced indigenous microbes in the initial food waste feedstock. Prevotella was always the most abundant genus under all conditions, which might contribute to the dominantly produced propionic acid among all conditions. The successfully suppressed growth of methanogenic archaea was reflected in terms of the low relative abundance (<1.5%) among all conditions. (3.1) Functional analysis of the customized acidification metabolic networks: Under the two selected HRTs, the potential and extant functions of acidification were unchanged between the two reactors (P > .05), which indicated a community-level redundancy in convergent potential and extant acidification functions even under a completely shifted microbial structure. However, the inclusion of THP diminished the potential and extant functions of acidification, in the meantime, shifting the main producer of butyric acid from Bacteroides to Prevotella through the expression of gene buk2. Among all conditions, the highest potential and extant functions in propionic acid production corresponded to the propionic acid-dominant acid profile in all reactors. The prevalently enriched Prevotella contributed to the stable propionic acid-dominant production via the acryloyl-CoA to propionyl phosphate to the propionic acid pathway. (3.2) Functional analysis of the carbohydrate hydrolysis niches: The extension of HRT from 4 days to 8 days didn’t impact the potential and extant functions of carbohydrate-activated enzymes (CAZys) and the hydrolysis of polysaccharides. Only two intermediate steps (gene malQ and lplD) during the hydrolysis of starch and pectin were enhanced with higher absolute transcriptional activities (mRNA/DNA RPKM) under HRT 8 days. The abundance ratio of the two main hydrolysis phyla Firmicutes: Bacteroidetes was unchanged between the two HRTs. When feeding with THP feedstock, the potential and extant functions of CAZys were both enhanced. All steps within the hydrolysis of cellulose (polysaccharides) exhibited increased absolute transcriptional activities (mRNA/DNA RPKM). The abundance ratio of Firmicutes: Bacteroidetes was decreased after the inclusion of THP on feedstock, which corresponded to the increased hydrolysis of polysaccharides- cellulose. Although the carbohydrate hydrolysis functions were improved after feeding with THP food waste, the total hydrolysis yield was not enhanced. The hydrolysis of other compounds such as proteins and lipids could also contribute to the total hydrolysis yield. The taxonomic analysis revealed that in all four conditions, the genus Prevotella presented with the highest potential functions in CAZys, while the genus Pararhodospirillum exhibited the highest extant functions in CAZys. This indicated that distinct bacteria were endowed with different functional potentials of CAZys and mobilized these functions differently. Overall, this research provides practical suggestions for engineering designs to maximize the VFA production profits from arrested anaerobic digestion of food waste: (1) A properly controlled HRT enables a long-term high-throughput production of VFA with stable yield and the unchanged dominant acid type (2) The inclusion of THP to the feedstock was not suggested to be applied to maximize the VFA yield even the dominant acid type may not change. (3) The dominantly produced propionic acid could be targeted by enriching the Prevotella genus to produce the propionic acid through the acryloyl-CoA to propionyl phosphate to the propionic acid pathway. Besides the engineering aspect, this research also specifically elucidates the long-time lumped and simplified acidification and carbohydrate hydrolysis processes with the extended metabolic databases including each reaction, key intermediates, enzymes, and corresponding genes. This expanded database served as an essential upstream process, which could be integrated into the current anaerobic digestion model. Additional applications could be extended to the human digestion systems' microbiome and be exploited commercially for other mixed-culture biosynthesis processes such as bioplastic and biodiesel production. Finally, the application of meta-omics-derived methodology revealed the functional redundancy and the potential discrepancy between the most abundant group and the most actively functional group underlying the formed black box of VFA production performance. This discussion of the nexus of performance-structure-function suggested the importance of applying meta-omics approaches in engineering practice, especially when feeding the mixed-culture community with real complex solid streams. The targeted VFA profiles cannot be reached without identifying the actual functional bacteria under selected engineering conditions.
67

Composting in the Urban Environment Utilizing Yard Waste and Food Waste in Fairfax County, Virginia

Argandona, Walter Solio 21 February 2020 (has links)
Urbanization alters the natural soil structure of landscapes. This has a negative impact on the environment. This degradation of the soil in the urban environment needs management practices that protect and restore the nutrient value in the soil. Soil is one of the most essential elements of landscapes. High quality soils make a major contribution to cleaning water, acting as a filtration system that purifies the water it absorbs. Soil also sustains microorganisms that promote vegetation growth and consequently food production, one of the most important human activities that allows us to thrive as a society. The poor soil conditions in the urban environment make it very difficult to sustain healthy trees and vegetation. Urban soil is "modified through the regrading, compaction, cutting and filling, and, sometimes, contamination that comes with creating buildings, roads and associated land uses", changing the physical, chemical and biological structure of soil. (Trowbridge and Bassuk 3) In general, urban areas require better waste management methods that could use an abundant resource of food and yard waste to make compost. This thesis focuses on composting organic waste in the McNair neighborhood of Fairfax County in order to produce a resource to improve the soil conditions. This improvement would support the vegetation in this urban environment, and, in addition, sequester carbon and divert materials that otherwise would go to landfills. This thesis demonstrates a sustainable method for composting food and yard waste in a mixed-use community in northern Virginia turning waste material into a resource. / Master of Landscape Architecture / The growth of cities has a negative impact on the native soil and vegetation. The expansion of urban areas weakens the microorganisms that live in the soils through soil compaction for the construction of roads and buildings, runoff pollution and the use of chemicals in lawns and gardens. These urban conditions challenge the growth of trees and vegetation in general. Using sustainable waste management practices in cities we can turn organic waste material and turn it into an organic fertilizer to sustain the microorganisms in the soil and promote the growth of vegetation in urban areas. This thesis focuses in composting food waste and yard waste in the McNair neighborhood in Fairfax in order to turn a waste material into a local resource that benefits the community by sustaining green areas and diverting organic waste from going to landfills.
68

Sustainable food security futures: Perspectives on food waste and information across the food supply chain

Irani, Zahir, Sharif, Amir M. January 2016 (has links)
Yes / The purpose of this paper is to signpost the genesis of food security and associated factors such that organisations, enterprises, policy makers and interested stakeholders can seek to explore and understand this important societal issue. The challenges that food security poses are eclectic in nature and cut through country, society, organisation and individual boundaries. Only through identifying these factors – hence identifying underlying factors of food waste and usage of information within food supply chains to untangle them – can we adopt enterprise interventions in order to initiate and mitigate food security risk. As a viewpoint piece, there is no empirical work to report in this paper. An exploratory review of the literature has allowed for the extraction of food security concerns that need the attention of stakeholders across the enterprise to ensure robust food supply chains can be are created, maintained and sustained through a better understanding and usage of information, knowledge and data This paper articulates six constructs that underpin the challenges of establishing food security. It is suggested that information relating to factors may support decision-makers within communities, organisations and enterprises to better understand these factors that then contribute towards enhanced food security. Relevant strategies or policies can then emerge and be developed such that strategic as well as operational interventions can be prioritised across national, regional or industry level. Underpinning the above, the waste within and across the food supply chain contributes to the six factors, also highlighting where additional focus may need to be applied to sustain food supply chains. This paper is a position paper that does not offer factual insight but rather highlights a direction of thought that others can consider exploring as part of wider research agendas in the topical area where enterprise, organisational, and information-based contributions may support the development of strategy-led food security policy. This paper provides reassuring insights that will help decision and policy makers assemble their thoughts when it comes to prioritising their communications and interventions amongst organisational/enterprise-level stakeholder groups involved in food security and food supply chain contexts. This paper has highlighted the need for more research around the human and organisational factors that are identified as both underpinning the need for food security and, as drivers of waste throughout the food supply chain. Indeed, there is further work needed to highlight the inter-relationships that exist and, which then feed into resulting interventions. To raise the importance of food security amongst differing stakeholder community groups at the organisational and enterprise level.
69

Wasted Pumpkins: A Real Halloween Horror Story

Surucu-Balci, Ebru, Berberoglu, B. 10 March 2022 (has links)
Yes / Purpose This study aims to understand pumpkin waste awareness among people by converting unstructured quantitative data into insightful information to understand the public's awareness of pumpkin waste during Halloween. Design/methodology/approach To fulfil the study's purpose, we extracted Halloween-related tweets by employing #halloween and #pumpkin hashtags and then investigated Halloween-related tweets via a topic modelling approach, specifically Latent Dirichlet Allocation. The tweets were collected from the UK between October 25th and November 7th, 2020. The analysis was completed with 11,744 tweets. Findings The topic modelling results revealed that people are aware of the pumpkin waste during Halloween. Furthermore, people tweet to reduce pumpkin waste by sharing recipes for using leftover pumpkins. Originality/value The study offers a novel approach to convert social media data into meaningful knowledge about public perception of food waste. This paper contributes to food waste literature by revealing people's awareness of pumpkin waste during Halloween using social media analytics. Norm activation model and communicative ecology theory are used for the theoretical underpinning of topic modelling.
70

Date labelling and the waste of dairy products by consumers

Thompson, Bethan January 2018 (has links)
The objective of this thesis is to advance our understanding of how consumers use date labels and the implications of date-label use for household dairy product waste. It does this by investigating the effect of psychological, social, and contextual factors on date-label use and willingness to consume dairy products in relation to the expiry date. These effects are tested using structural equation models and survey data gathered from 548 Scottish consumers. The results of this study make two contributions to the literature on date-labelling and food waste. The first contribution is primarily theoretical. By improving our understanding of how consumers use date labels and the implications of date-label use for household dairy product waste, it supports the contention that food waste is best understood, not as a behaviour, but as the outcome of multiple behaviours. It argues that in order to understand why food waste is created, it is important to identify the factors that affect the individual behaviours that lead to it, such as date-label use, and how these behaviours relate to one another. These results also have implications for communications and campaigning around food waste reduction. The second contribution has policy relevance. It provides evidence of the likely limited effect of increasing the number of dairy products labelled with a best-before date rather than a use-by date on food waste. This is an approach recently proposed to reduce household food waste. It finds that better knowledge of the best-before date is associated with a higher willingness to consume products after the best-before date has passed. However, perceived risks about consuming products beyond their best-before date, including not just safety but quality, freshness, and social acceptability, appear to interact with date-label knowledge and dampen its influence. It argues that to be effective, any changes in date-labelling should be accompanied by communication that goes beyond improving date-label knowledge, and addresses the multifaceted nature of related risk perceptions and conceptions of date-label trust.

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