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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.
71

An assessment of the household food wastage in a developing country: a case study of five areas in the City of Tshwane Metropolitan Municipality, Gauteng Province, South Africa

Ramukhwatho, Fhumulani Ruth 24 August 2016 (has links)
Food waste has been proclaimed to be the key issue of concern that has drawn the attention of national and international scientific communities. This is due to changes in food systems and global situations. The issue of food waste is important because a large amount of food is being wasted during the production and distribution of food. One-third of food produced globally is wasted or lost from farm to fork. The primary aim of this study was to evaluate and quantify the factors that contribute to generation of household food waste. The evaluation was done using face-to-face interviews based on a structured questionnaire and the actual weighing of households’ food wasted was quantified using a weighing kitchen scale. A total of 210 participants were interviewed. Food waste samples were collected from five selected study areas of the City of Tshwane Metropolitan Municipality (CTMM): Atteridgeville Ext 6, 16 and 17, Lyttelton, Montana Park, Olievenhoutbosch Ext 36 and Silver Lakes Golf Estate, in Gauteng province, South Africa. The acquired data was captured into Microsoft Excel, and analysed. The chi-square statistical test was done using SAS statistical software. Out of 210 interviewed participants, 55% of the households had a monthly income of R10 000+ and 45% had a monthly income of less than R10 000. A total of 59% of respondents agreed that they wasted food, while 41% thought they did not waste food at all. The results also show that 35% of households included in the survey in selected areas of the CTMM threw away pap (referred as maize porridge), 26% wasted rice, 25% bread and 14% fruit and vegetables. Households wasted an average total of 6 kg per week per household. This was attributed to over preparation of porridge and rice; buying too much food; falling for special offers; poor storage; food residue, and fruit and vegetables going off. Households with a monthly income of R500 - R5 000 wasted more food than households with an income of more than R5 000. As such, it can be concluded that income has an impact on the amount of food wasted within the selected areas of CTMM. Moreover, analysis of the data confirmed that there is a statistically significant relationship between income level and food waste. The statistical chi-square test was applied and a probability value (p-value) of < 0.0001 was obtained, indicating that the difference between income categories was more than just a random pattern. (Note that any p-value of < 0.05 is considered to be statistically significant, i.e. an indication of an underlying consistent, non-random pattern.) / Environmental Sciences / M. Sc. (Environmental Management)
72

Food corporations and government rethinking food waste strategies in Johannesburg City

Pheto, Bokang January 2018 (has links)
Global nations are awakening to the realisation and manifestation of actual food insecurity. Voices which advocate for food security have always been there but were overshadowed by corporate ignorance and overpopulation. Corporate food waste plays a major role in contributing to food insecurity although the spotlight is hardly put on them. As the economic hub of South Africa, the City of Johannesburg (CoJ) must take the lead in rethinking food waste reduction strategies in food corporations selling fruits and vegetables where the most waste occurs in the country. The level of fruit and vegetable wastage should decline in order to counter the adverse effects of food waste. The aim of this study is to establish strategic ways to decrease fruit and vegetable wastage at corporate level in the CoJ. This is achieved by determining contributing factors to food waste including improving food waste reduction models with the intervention and collaboration of food and wholesale stores as well as government. Face-to-face interviews, online surveys and a case study were methods used to answer the study objective. Responses from the field work show that many fruit and vegetable customers opt for conventional or ‘ordinary’ looking foods than ‘wonky’ looking ones. Also, many of the food stores do not have food waste reduction models to guide them, leading to a lot of food being dumped. Furthermore, the food health and safety criteria seem to be a leading contributor to food waste. These results indicate that food waste reduction is also important at pre-consumer stages. On this basis, it is recommended that a solid partnership between food corporations and Johannesburg city is formed in solidarity against food waste. Serious measures must be put in place in order to minimise fruit and vegetable wastage on both sides. These changes have potential to have an immense impact on the economy, environment and society. Further research should be undertaken to identify other factors that could be helpful in the quest to limit food waste in food corporations. / Development Studies / M.A. (Development Studies)
73

Plýtvání potravinami v USA jako otázka tvorby federální politiky / Food Waste in the United States as an Issue of Federal Public Policy Making

Hlaváčková, Anna January 2020 (has links)
The Master's thesis "Food Waste in the United States as an Issue of Federal Public Policy Making" analyzes the role of the federal government in dealing with food waste. It mainly focuses on federal legislation, but it also examines actions on the state level to illustrate the contrast between the two. In the thesis, the author examines the causes and sources of food waste, federal jurisdiction for intervention, and the history of passed legislation, as well as proposed legislation, and solutions. The main goal of the thesis is to demonstrate that federal involvement is fundamental in achieving any significant change, but so far has failed to do so. Primary literature consisting largely of bills, materials published by federal agencies, and reports by non-profit organizations were used to uncover the character of passed legislation. Academic secondary literature in the form of articles, reports, and factsheets offered context to understand the scope and impacts of the legislation. Analysis of those sources revealed federal authority to deal with the issue, as well as possible obstacles standing in the way of an extensive federal intervention. Research also showed that in the absence of federal action, some states have stepped up to introduce legislation to reduce food waste, but this legislation is...
74

Food Waste Diversion Programming in Post-Secondary Education

Alattar, Manar Arica 30 March 2018 (has links)
The urgent need for reform of USA and global food systems is evident in the pervasiveness of both food waste and food insecurity. Such an inefficient system strains the environmental, social, and economic systems on which it relies. Although policy and infrastructure changes are essential, consumers can play a significant role by decreasing their food waste, given that consumer waste represents 60% of the waste along the food cycle in developed countries. Incorporation of food literacy and food waste education in school curricula may provide a meaningful entry point for promoting food waste reduction skills. This dissertation presents context on the suitability of food systems for science and climate change education. Practical implementation of this concept is then explored through a survey of 495 students at Portland State University that presents the reported knowledge, attitudes, emotions, and beliefs related to food waste. The underlying factors that influence student food waste behavior and intent to change such behavior are likewise explored. I also provide a description and assessment of a food waste diversion program, No Scrap Left Behind, that was developed and piloted at PSU. I found that knowledge, attitudes, emotions, beliefs, and reported food-related behaviors were generally positive. Students were also interested in taking action and perceived that their food-related actions could make a difference. Intent to change food waste behaviors was influenced by: 1) sustainability actions, 2) food waste diversion actions, 3) attitudes about composting, 4) composting, 5) reported household food waste, 6) material reuse attitudes. Reported food waste diversion behaviors were related to: 1) intent to reduce food waste, 2) knowledge and attitudes towards composting, and 3) attitudes about reuse. The measures of reported knowledge, attitudes, emotions, beliefs, and behaviors were not significantly influenced by No Scrap Left Behind programming, but actual measured food waste was decreased by one-fourth both over an academic year and within an academic term of programming. This indicates that students are amenable to food waste behavior change when given the encouragement and infrastructure to make that change. Further research may consider opportunities for food waste education beyond the cafeteria setting, particularly as an entry into more complex discussions around environmental, social, and economic systems and concepts.
75

Fett i de kommunala avloppssystemen – matavfall på fel plats / Fat in the municipal sewer system – food waste in the wrong place

Lundgren, Johan, William, Hultqvist January 2018 (has links)
Tidigare undersökningar visar att fettproblematiken i de kommunala ledningsnäten är ökande. Fettet som hamnar i avloppen leder till drift- och underhållskostnader, men leder även till problem för att nå de lagar och regler som ställs på VA-huvudmännen. Vad gör huvudmännen åt detta problem? Är användningen av bioteknik en lösning? Vilka åtgärder finns mot hushållen? I denna uppsats har en litteraturstudie genomförts om fett i avlopp, en enkätstudie för att undersöka privatpersoners kunskap om matavfallssortering och även intervjuer med personer från företag inom VA. Resultaten visar att det finns indikationer på att informationen ut till privatpersoner kan förbättras från enkätstudien. Informationen som finns på kommunens hemsida som är riktad mot privatpersoner är svåråtkomlig. Fett i avlopp är ofta ett osynligt problem för allmänheten. Därför krävs informationsinsatser för att minska uppkomsten. Användandet av fettavskiljare är en effektiv åtgärd så länge de är tillräckligt dimensionerade och töms varje månad. Bioteknikens påverkan i de kommunala ledningsnäten bör undersökas vidare i en större studie. / Previous studies show that problems with fat in the municipal sewer systems are increasing. The fat that ends up in the drain leads to costs related to operation and maintenance, as well as issues with reaching the laws and rules that the owners of the water- and wastewater infrastructure needs to apply. What are the sewer system owners doing against this problem? Is the use of biotechnology a part of the solution? What actions are available towards the households? In this study we have done a literature study about fat in sewers, a survey to investigate the publics knowledge about food waste separation. We have also performed interviews with companies within the field. The results from the survey shows indications that the information to the public can be improved. The accessible information aimed towards the public on the municipality's website is hard to reach. Fat in sewers is often an invisible problem to the individuals. Because of this efforts with information is needed to lower the emergence of fat. The use of grease traps is an effective solution if they are correctly dimensioned and are emptied every month. The effect that biotechnology have on the wastewater system ought to be investigated in a larger study.
76

Predictive Regression Model Evaluation : Evaluating Predictive Machine Learning Models to Reduce Food Waste in the Dairy Industry / Utvärdering av prediktiva regressionsmodeller : Utvärdering av prediktiva maskininlärningsmodeller för att minska matsvinn i mejeriindustrin

Carlsson, Alexander January 2023 (has links)
Food waste in the food industry is often a result from the complex nature of food production. Uncertainty is always present as yields vary and as there is a chain of consumer demand from stores to producers. Food waste is a waste of both natural and economic resources affecting both the planet and the producer. The environmental impact is further affected as excessive production that leads to waste correlates to an excessive carbon footprint from excessive farming, transports, and processing. Additional environmental impacts are excessive land usage and overfertilization. In order to aid in the reduction of food waste in the food industry, this thesis evaluates a machine learning approach to predicting commercial waste. This thesis evaluates 11 predictive machine learning models on their predictability on commercial food waste at a large product producing company in the dairy industry. The models are evaluated according to the two metrics; Root Mean Squared Error (RMSE) and Mean Absolute Error (MAE). Based on the models’ RMSE and MAE metrics, the Random Forest model proved to be the most suitable model. It presented the best and statistically significant RMSE. It also produced the best MAE but without statistical significance to gradient boost and Support Vector Regression (SVR), indicating that the difference in performance between the models, according to MAE, are within a variation span that can occur due to chance. / Matsvinn inom matrindustirn är ofta ett resultat av komplexiteten inom matproduktion. Variation i skördar och efterfrågan genom hela kedjan av kunder och konsumenter är alla bidragande faktorer. Matsvinn är ett slöseri på både naturliga och ekonomiska resurser som påverkar både miljön och produktionsbolagets ekonomi negativt. Miljöpåverkan påverkas ytterligare då överproduktion som leder till avfall korrelerar med överdrivet utsfläpp av koldioxid från överdrivet jordbruk, transporter, och tillverkning. Överproduktion av mat leder även till överdriven använding av mark och övergödning. För att bidra till minskat matsvinn i matindustrin, utvärderar denna avhandling 11 prediktiva regressionsmodeller om deras förmåga att förutse matsvinn inom produktion vid en mejeriproducent. Modellerna utvärderas enligt två mått; RMSE och MAE. Baserat på modellernas RMSE-mått visade sig Random Forest vara den mest lämpliga modellen. Den producerade bäst och statistiskt signifikant RMSE. Modellen producerade även bäst MAE men icke signifikanta resultat till gradient boost och SVR indikerar skillnaden mellan dessa modellers prestanda, enligt MAE, ligger inom ramen för slumpmässig varians.
77

Strategier för ett minskat matsvinn inom kommunal skolverksamhet

Mårtensson, Adina, Suhonjic, Meliha January 2016 (has links)
Today we stand in front of major environmental problems both at global and national level. This report deals with the issue of food waste which is a significant environmental problem worldwide. Food waste also has a strong impact on the economy. The aim of this work was to examine what strategies the municipalities work with to reduce food waste in school catering. The aim was also to analyze and suggest strategies that could be successful in decreasing the problem with food waste. The study included four municipalities with a variety of size and population. Our method consisted of interviews with 11 key persons working both in the selected school kitchens and at least one nutrition manager in each municipality. The result of the study showed that municipalities work with different strategies to reduce food waste in schools. Some of them focus on educating their staff, others have different methods to measure food wastage in school kitchens in order to understand how much is thrown away and encourage improvements. Furthermore the result of the study points at the importance of communication as a key factor in dealing with food waste. Communication between students, teachers and the kitchen staff could improve in order to make awareness of the problem with food waste. The study showed that there is not a reference value for what little or much food waste is. A reference value can increase the motivation of school kitchens to develop new strategies for reduced food waste.
78

Hygienisering av torkat bioavfall

Svensson, Malin January 2007 (has links)
<p>The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc. Thesis Work was to first find a suitable method to attain hygienic safety through a literature study, to test and evaluate the method and to test if a method changes the composition or structure of the material. An existing recipe for food waste was developed and used throughout the work.</p><p>Heating of the dried biowaste is probably the most suitable method to reach and attain a hygienically safe product. Three time-temperature proportions were tested, 55, 70 and 80°C. The results show that a raise in temperature lead to a change in the composition of the dried biowaste, most distinctively for the highest temperature. Nitrogen losses of 21% of the total nitrogen content were noticed. A composting experiment showed that the biowaste heated to the highest temperature was decomposed to a higher degree. It does not, however, seem like a heating process will decrease the possibility to use dried biowaste as a soil improvement.</p> / <p>Projektet Torrkonservering av matavfall från hushåll innefattar en ny teknik för torkning och lagring av bioavfall, hushållens sortering och vidare användning av det torkade materialet. För att sluta det naturliga kretsloppet utreds om det torkade bioavfallet kan användas som ett jordförbättringsmedel. När organiskt avfall ska användas som ett jordförbättringsmedel ställs krav på hygienisk säkerhet. Examensarbetets syfte var att, genom litteraturstudier, utreda lämplig hygieniseringsmetod att vidare testa praktiskt, samt att testa om en hygieniseringsprocess medför några förändringar på det torkade bioavfallets materialegenskaper. Ett befintligt standardrecept på matavfall vidareutvecklades och användes.</p><p>Resultaten tyder på att upphettning av det torkade bioavfallet förmodligen är den mest lämpliga hygieniseringsmetoden. Tre olika tid- temperaturförhållanden testades, 55, 70 och 80°C. Laborationer och analyser tyder på att det torkade bioavfallet genomgår en viss förändring av den kemiska sammansättningen vid upphettning, vilket är tydligast för den högsta hygieniseringstemperaturen. Bland annat sker kväveförluster på upp till 21 % av totalkvävet. Komposteringstester visar på att nedbrytningsgraden är högst för bioavfall som hygieniserats vid den högsta temperaturen. Det verkar inte som om hygienisering, genom upphettning, minskar möjligheten att använda torkat bioavfall som ett jordförbättringsmedel.</p>
79

Bäst före 2014 : En studie om matsvinn i livsmedelsbutiker

Forssell, Mikael, Hedlund, Jonas, Ribinge, Oskar January 2014 (has links)
Syfte Vårt syfte är att ge en djupare förståelse för det matsvinn som uppstår i livsmedelsbutiker genom att analysera och utreda servicelandskapets, personalens och kundens påverkan på matsvinn. Med koppling till detta syfte har vi valt följande forskningsfråga: På vilka sätt kan livsmedelsbutiker arbeta för att minimera sitt matsvinn med hänsyn till butikernas lönsamhet och kundnöjdhet? Metod Denna uppsats är en kvalitativ studie som haft sin början i ett empiriskt problem som vi ville skapa en djupare förståelse kring, vilket innebär att vår uppsats haft sin början i induktionen. Under processens gång har vi arbetat parallellt med empiri och teori, därför har studien haft ett växelspel mellan induktion och deduktion. Insamlingen av material har skett genom primära och sekundära källor där det empiriska materialet skett genom semistrukturerade intervjuer. Slutsatser I vår arbetsprocess har vi kunnat urskilja att servicelandskapet, personalen och kunden är de faktorer som påverkar matsvinnet inom dagligvaruhandeln. Vi har lyft fram att exponeringar, inköp, service och kunskap är återkommande tendenser som är avgörande för matsvinnet som uppstår. Under arbetsprocessens gång har vi identifierat att butikernas främsta fokus är lönsamhet. Baserat på våra föreslagna arbetssätts möjliga påverkan på matsvinn, försäljning och kundnöjdhet, ser vi att livsmedelsbutikers lönsamhet har potential att öka eller förbli opåverkad, samtidigt som deras matsvinn har potential att minska.
80

Mixed fuels composed of household waste and waste wood : Characterization, combustion behaviour and potential emissions

Edo Giménez, Mar January 2016 (has links)
Incineration with energy recovery is the main disposal strategy for waste that cannot be reused or recycled, and a well-established source of energy in Europe, especially in Sweden where 2.2 Mtonnes of waste including domestic and imported municipal solid waste (MSW) and waste wood (WW) were combusted during 2015. However, owing to its inherent heterogeneous composition, inclusion of such waste in Waste-to-energy (WtE) technologies is challenging. These heterogeneities may lead to operationally-related issues in the WtE facilities and contribute to toxic emissions, which can be reduced by waste pre-treatment technologies.    This thesis examines the variations in the composition of MSW and WW streams used as a fuel supply in WtE facilities after undergoing waste pre-treatment technologies, and the effect of fuel composition on its combustion behaviour and formation of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The overall objective is to contribute to a more thorough understanding of the selection of waste pre-treatment technologies to mitigate harmful emissions into the atmosphere when waste fuels are combusted in WtE facilities.    This thesis describes the high variability of contaminants in domestic and imported WW and suggests adaptation of WW pre-treatment techniques to produce fuels with a low potential for generating pollutants. A comparison of mechanical solid waste pre-treatments revealed that screening and shredding is more efficient than extrusion for reducing emissions of pollutants such as PCDDs and PCDFs in combustion. The evaluation of the combustion behaviour of MSW-based fuels showed a three-stage oxidative decomposition, and an acceleration of the decomposition of the MSW compared to the lignocellulosic materials, which may be attributed to the presence of food waste and plastics in the MSW. Combustion tests of fuel blends containing WW and MSW-based fuels with different food waste content suggested that WW, not food waste content, is the key factor for the formation of PCDDs, PCDFs, and polychlorinated biphenyls (PCB), benzenes (PCBzs) and phenols (PCPhs). Torrefaction may be a suitable technology for improving the properties of waste as a fuel e.g. due to its low PCDD and PCDF emissions. / Förbränning med energiåtervinning är det huvudsakliga sättet att ta hand om avfall som inte kan återanvändas eller återvinnas. Det är en väletablerad energikälla i Europa och särskilt i Sverige där 2,2 miljoner ton avfall, däribland inhemskt och importerat hushållsavfall och returträ, förbrändes under 2015. På grund av den heterogena sammansättningen hos hushållsavfall och returträ är förbränning av dessa material i anläggningar med energiåtervinning (så kallade WtE-anläggningar) förknippade med en del driftsrelaterade utmaningar. Det kan även ge upphov till miljöfarliga utsläpp, som dock kan reduceras genom förbehandling av avfallet. I denna avhandling har variationer i sammansättningen hos hushållsavfall och returträ som förbränns i WtE-anläggningar undersökts. Effekten av bränslemixens sammansättning och ev förbehandling på bränslets förbränningsegenskaper samt bildning av långlivade organiska föroreningar (så kallade POPar) såsom polyklorerade dibenso-p-dioxiner och polyklorerade dibensofuraner vid förbränning har utvärderats. Det övergripande målet är att bidra till en djupare förståelse av hur valet av förbehandlingsteknik för avfall kan bidra till att minska skadliga utsläpp till luft när avfallsbränslen förbränns i WtE-anläggningar. Denna avhandling beskriver den stora variabiliteten av metall- och materialföroreningar i inhemskt och importerat returträ och föreslår förbehandlingstekniker för att producera bränslen med låg potential att generera föroreningar. En jämförelse av mekaniska förbehandlingstekniker visade att mekanisk sönderdelning och separering (krossning och siktning) är mer effektivt än s.k. högtrycks-pressning för att minska utsläppen av föroreningar som dioxiner och furaner vid förbränning. Utvärderingen av bränslemixar innehållande hushållsavfall uppvisade en oxidativ nedbrytning i tre steg vid förbränning, och en accelererad nedbrytning av avfallsmaterialet jämfört med vedmaterialet i bränslet, troligen som effekt av innehållet av matavfall och plast i hushållsavfallet. Förbränningsförsök med bränsleblandningar av returträ och hushållsavfall med olika innehåll av matavfall visade att mängden returträ, och inte mängden matavfall, är den viktigaste faktorn för bildning av dioxiner, furaner, klorbifenyler, klorbensener, och klorfenoler. Torrefiering kan vara en lämplig teknik för att förbättra avfallets bränsleegenskaper, t.ex. på grund av dess låga emissioner.

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