Tesis: "Food contamination"

1

Plummer, Stephanie C. "Food Contamination Narratives in United States News Media". Bowling Green State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1237761803.

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2

Tudor, E. A. "Yeast contamination of meats and processing equipment". Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234640.

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3

Pastorini, Elisabetta. "Analytical methodologies for evaluating mycotoxin contamination in food safety". Doctoral thesis, La Sapienza, 2006. http://hdl.handle.net/11573/916869.

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4

Fapohunda, Ajibola Oladapo Idowu. "Bacterial contamination and growth on red meat and fish". Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321397.

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5

Gautam, Omprasad. "Food hygiene intervention to improve food hygiene behaviours and reduce food contamination in Nepal : an exploratory trial". Thesis, London School of Hygiene and Tropical Medicine (University of London), 2015. http://researchonline.lshtm.ac.uk/2531624/.

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Objectives: This thesis describes a study that designed, implemented and assessed the effect of a food hygiene intervention on mothers’ food hygiene practices as primary outcomes, and the impact of the interventions on the level of microbiological contamination in food as a secondary outcome. An additional objective was to explore whether food hygiene interventions can be integrated into nutrition, health and water, sanitation and hygiene (WASH) strategies and programmes in Nepal. Methods: The theoretical and practical approach of Behaviour Centred Designed was employed. In step-A: Assess, a systematic literature review was conducted to identify sectoral knowledge and programmatic gaps on food hygiene and sectoral policy documents analysis was done as part of gray literature review to ascertain whether food hygiene interventions can be integrated into Nepal’s health, WASH and nutrition programming. In step-B: Build, formative research was carried out to identify and prioritise key food hygiene behaviours, and inform the intervention design. In step-C: Create, a scalable food hygiene intervention package was designed and tested using a novel approach to behaviour change employing emotional drivers and changing behaviour settings. In Step-D, the intervention was Delivered by female food hygiene motivators in four intervention clusters over a period of three months while four clusters acted as a control group in a rural area of Nepal. In Step E: Evaluate, a Cluster Randomized, Before-After study with Control (BAC) was employed. Behavioural outcomes were measured before and after the intervention in 239 households with a child aged 6-59 months in four intervention and four control clusters. The microbiological contamination in commonly-used child foods was measured in a sub-sample of 80 households. Results: Systematic review identified the need for research into improving food hygiene behaviour to reduce contamination in food and improve health outcomes in low-income settings. Nepal’s policy environment can enable the integration of food hygiene promotion within ongoing WASH, nutrition and health programmes. Five key food hygiene risk behaviours were prioritized, and likely determinants of behaviour change were identified through formative research. The motivational and creative food hygiene intervention package was designed and delivered in community settings. The intervention was effective in significantly improving multiple food hygiene behaviours. The 5 targeted food hygiene 4 behaviours were rare at baseline. Forty five days after the 3 months intervention, key behaviours were more common in the intervention group than in the control group (43% [SD14] vs. 2% [SD 2], p=0.02). The difference of differences was an increase in mean proportion of 42% (p=0.02). The intervention appeared to be equally effective in improving all five behaviours and in all intervention clusters. Commonly-used child foods from the intervention and control clusters were heavily contaminated with total coliforms and E. coli during child feeding at baseline and the behavioural intervention was effective in significantly reducing the contamination in the intervention group during follow-up. After adjusting for baseline, the intervention reduces the mean coliform count by -2.00 log10 cfu/gm (p=0.020) and E. coli by -1.00 log10 cfu/gm (p=0.083). Contamination in water was low as compared to food at baseline and did not improve after the intervention. Conclusion: This systematic approach employing emotional drivers and change in behavioural settings substantially altered multiple food hygiene behaviours and reduced microbial contamination in commonly-used child food in Nepal. Ingestion of microbes by children can only be eliminated if the food hygiene intervention deals with all key behaviours. This study responds to an important evidence gap. Current evidence, to which this study has contributed , is sufficient to merit prioritisation of food hygiene by those concerned with designing more effective WASH, health and nutrition programmes. The work suggests that interventions on food hygiene should have a higher priority than those on water treatment, which is not currently the case in development projects. The BCD approach provided a theory of change and a useful process framework for the design, delivery and evaluation of the intervention. Additional research is needed to test the impact of such interventions on both behaviour and health outcomes. Further tests would help to determine if the intervention can be replicated in diverse settings and at large scale and so add value to existing programmatic responses to poor WASH and undernutrition. The implementation of a tested food hygiene package through a scalable pilot was identified as a next step towards demonstrating the delivery of hygiene interventions through existing service delivery mechanisms in Nepal.

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6

Rip, Diane. "Sample preparation methods and molecular based detection for the rapid isolation and identification of Listeria monocytogenes in food samples". Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1346_1255007553.

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Listeria monocytogenes is a Gram-positive bacterium responsible for listeriosis, a food-borne disease, which may result in severe illness and possible death. The importance of L. monocytogenes as a food-borne pathogen has been recognized since the 1980's when a correlation between the cunsumption of contaminated foodstuffs and human listeriosis outbreaks was observed. Listeriosis occurs with the ingestion of contaminated foods. The aim of this study involved developing DNA based methods to aid the food industry for the fast detection of L. monocytogenes in food products. Therefore assays were developed in such a way that they will have potential applications in the food idustry.

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7

Hossain, Rakia. "Safe Food in Bangladesh: Perception and Influences on Safe Food Purchasing". Thesis, Griffith University, 2020. http://hdl.handle.net/10072/395524.

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Unsafe food is a global concern as it causes significant health risks to a large number of people. It has many and varied short and long-term health impacts such as salmonellosis, shigellosis, typhoid fever and even cancer. Therefore, safe food is the central concern for all stakeholders in the food system from producers to the marketplace to the household where the food is finally consumed. As an end point of the food safety chain, consumers demonstrate various strategies to ensure safe food from purchasing to consumption. Consumers’ food purchasing behaviour is greatly influenced by culture, economy, psychology and lifestyle. Therefore, understanding consumer attitude towards safe food is an important aspect for ensuring safe food and reducing foodborne illnesses in a community. In developing countries like Bangladesh, food contamination and the food adulteration situation are widely known public health issues as well as concerns of growing importance in recent times. However, very little is known about consumer safe food purchasing behaviour in Bangladesh. Hence, this current research attempts to explore primary household food purchasers’ (PHFP) perception of safe food, their information sources of safe food knowledge and application of this knowledge when purchasing safe foods. To evaluate these, the current study applied a mixed method approach where quantitative surveys and qualitative focus group discussions were used as data collection methods. The findings of the study revealed that the primary household food purchaser (PHFP) was more concerned about the usage of chemicals in food and they reported considering chemical food hazards during food purchasing. Among other safe food purchasing factors freshness was found as one of the most important factors. Besides freshness, the PHFP considered appearance, taste, colour, seasonality, origin of the product and expiry date, as features to guide safe food purchasing. More than 50% of the PHFP reported that` safe food has not been diminished in the last five years in Bangladesh. Most of the PHFP relied on friends and family members as their information sources for safe food purchasing. Regardless of their perception, the PHFP showed much concern about safe food, hence, further planning and implementation of food safety related programs, as well as better education about safe food can help to mitigate these issues in this community. A number of recommendations were provided to inform future food safety related programs and additional research that aims to reduce foodborne illnesses in this community.
Thesis (Masters)
Master of Medical Research (MMedRes)
School of Medical Science
Griffith Health
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8

Chan, Hon-wing y 陳漢榮. "Food poisoning outbreaks in Hong Kong resulting from shellfish contamination". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31253349.

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Chan, Hon-wing. "Food poisoning outbreaks in Hong Kong resulting from shellfish contamination /". Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17457762.

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10

Mack, James C. "Policy Implications of Intentional Contamination of the Retail Food Chain". ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7038.

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The retail food safety chain is vulnerable to deliberate contamination, yet food safety professionals and emergency managers typically respond to intentional contamination in different ways. Little is known about the practices of environmental health food safety professionals (EHFSP) as compared to emergency managers and whether those approaches can be combined to more successfully impede intentional food contamination. The purpose of this narrative policy analysis was to use routine activity theory to compare the narratives of EHFSPs and emergency managers to determine whether there are opportunities to better understand the relationship between vulnerability and resiliency of the retail food safety chain. Data were primarily collected through interviews with 5 EHFSPs and 5 emergency managers from various regions in the United States. Interview data were inductively coded and then subjected to Braun and Clarke's thematic analysis procedure. Key findings indicate that EHFSPs generally are ill-suited to meet resiliency goals, ambivalence voiced by EHFSPs results from a lack of continual preparedness training, and neither EHFSPs nor emergency management officials' familiarity with the social dimensions of resiliency is at a point where they can design adequate measures for a resilient retail food system. Therefore, recommendations to policy makers focus on a need for an enhanced training that is inspired by principles of emergency management so that they are better able to respond to acts of intentional contamination, thereby building a resilient retail food chain with economic and social benefits.

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11

Misner, Scottie y Evelyn Whitmer. "Food Safety Know-how". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146682.

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1p.
Most of the "bad food" reported illnesses are due to bacterial contamination. Nearly all of these cases can be linked to improper food handling, both in our homes and in restaurants. This article briefly discusses the causes of food contamination and how to handle food safely.

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12

Msuya, Joan. "Food Safety of Homemade Complementary Foods In Morogoro Municipality -Tanzania". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471527745.

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13

Laws, Jacob. "Conduits of contamination to contemporary food webs of the Norfolk Broads". Thesis, Queen Mary, University of London, 2011. http://qmro.qmul.ac.uk/xmlui/handle/123456789/2424.

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During the 1960s-1980s antifouling applications containing the organotin tributyltin (TBT) were applied to craft on the Norfolk Broads, leaving a legacy of contaminants in sediments. Previously, no research had been undertaken to investigate the implications that this legacy may have for the ecological integrity of the Norfolk Broads aquatic ecosystem. Eight sites in the Norfolk Broads that represented a gradient of contamination (as measured by sediment TBT concentrations) were selected. Contamination was evident in invertebrates and fish but was lower than sediments, as total organic carbon and species specific metabolic capacity for TBT controlled bioavailability To examine TBT impacts at the community scale, novel metrics were applied to food webs defined by stable isotopes of carbon and nitrogen. Two metrics were reduced in response to increasing TBT contamination, suggesting simplification of food webs along the contaminant gradient; where loss of key food web properties such as trophic diversity and shortened food chain length could reduce resilience to further system perturbations. I hypothesised that chironomids emerging from sites contaminated with organotins would carry with them an organotin burden, which would be reflected in terrestrial predators such as spiders via trophic transfer. A combination of spider and chironomid stable isotopes (principally δ 13C) and isotope mixing models indicated considerable chironomid contribution to spider biomass at all four sites (34-88%). Subsequent organotin analyses revealed consistent low level, butyltin (di-butyltin; DBT) contamination in chironomids and spider predators from the most contaminated site.

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Pisani, L. F. "SERUM AMYLOID A IN RUMINANTS: DIAGNOSTIC VALUE AND FOOD CONTAMINATION ASSESSMENT". Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150187.

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The aims of the work presented in this thesis were to investigate the bovine acute phase protein Serum Amyloid A, focussing on its value as safety marker in farm animals. SAA can be considered as a natural anti-inflammatory and immunomodulatory agent and local expression of SAA, at the site of the initial acute phase reaction, could protect against the deleterious effects of inflammation. In this study whether SAA can be isolated from tissues of bovine with clinical amyloidosis was investigated. We also investigated if AA fibrils present in milk can be then found in cheese after caseification, i.e. if the process of ripeining can degrade the AA fibrils. In bovine, SAA was identified as potential marker of mastitis, and SAA milk concentration in milk increases before the raising of somatic cells. In this thesis two aspect of the involvement of SAA in food safety were explored: a)the acute phase reaction, strongly focused on the mammary gland. The animal model chosen was water buffalo, since no information is available so far about the acute phase reaction in this species. The acute phase proteins sequences are unknown, and also their concentration in physiological and pathological conditions are not established. b)The possibility that high concentration of SAA in milk induce the formation of amyloid fibrils, which are considered to be potentially dangerous for human safety. Results presented in this thesis advanced the knowledge of the acute phase reaction in water buffalo: the five APPs included in this investigation, namely Serum amyloid A, Haptoglobin, Ceruloplasmin, α1-acid glycoprotein and Lipolysaccaride Binding Protein were sequenced for the first time, and two of them were quantified. In the second part of the thesis, we purified amyloid fibrils from amyloidosis-affected cows, and added purified fibrils at a given concentration in milk before ripening. Results demonstrated the presence of insoluble fibrils in cheese added with amyloid proteins, even if a lower amount of precipitated insoluble SAA could be detected also in negative control cheese.

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Caldwell, Lucius. "The Use of Vinegar Vapor and Post-Harvest Biological Control to Reduce Patulin in Apple Cider". Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/CaldwellL2009.pdf.

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16

Spooner, Ashley. "The mercury contamination in fish and the subsequent public health effects". [Denver, Colo.] : Regis University, 2006. http://165.236.235.140/lib/ASpooner2007.pdf.

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Senior Honors thesis--Regis University, Denver, Colo., 2007.
"May 2006"--T.p. Date of submission on Certification of Authorship page: 4/16/07. Title from PDF title page (viewed on June 26, 2007). Includes bibliographical references.

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17

Weeks, Mark E. "An investigation into the global cellular responses of Listeria monocytogenes during the transition from exponential to stationary growth phase". Thesis, University of Kent, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268322.

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18

De, Beer H. y C. J. Hugo. "Potential sources of chryseobacterium contamination during poultry processing : a pilot study". Journal for New Generation Sciences, Vol 8, Issue 3: Central University of Technology, Free State, Bloemfontein, 2010. http://hdl.handle.net/11462/566.

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Published Article
The genus Chryseobacterium is often found in food and is regarded as a food spoilage organism. In this study, the source of the chryseobacteria was uncertain. As an exploratory investigation, the potential source of chryseobacterial contamination was determined. Total bacteria counts and yellow-pigmented colony counts were performed. Chryseobacterium species were present on poultry carcasses at all stages of processing. Total Chryseobacterium counts increased from 5.6 to 11.8 % after the brine injection stage. A significant increase in total Chryseobacterium counts (20.0 and 25.2 %) in the processing waters occurred where cutting up of the carcasses was involved. It is speculated that live chickens are the source of contamination.

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Pillsbury, Laura Anne. "Food cultures, total diet studies and risk management implications for global food policy and public health /". Connect to this title, 2008. http://scholarworks.umass.edu/theses/157/.

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20

Yeung, Lau-kong. "Review of food safety policy in Hong Kong : challenges brought by ciguatera on the safe consumption of live reef fish /". View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37118705.

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Pinegar, Arthur John. "Escherichia coli in retail processed foods : a source of pathogenic strains for man". Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236713.

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22

Mulroy, Mary Geraldine. "The release of contaminants by leaching from boil-in-bag laminates". Thesis, De Montfort University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330115.

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23

Santana, Marina Ferreira Mourão. "Effects of microplastics contamination on marine biota". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-20032016-174906/.

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Microplastic pollution (particles < 5mm) is one of the most widespread impacts from modern society. Here, microplastic impacts were investigated through experimental assessments considering different exposure scenarios using mussels and micro-PVC as models. These aimed to investigate mussels\' physiological signs of stress under acute and chronic exposures and microplastics transference, assimilation and retention along food chains. In acute exposures, PVC intake affected mussels\' physiology over time, also influenced by plastics additives and particle concentration. Interactions among exposure factors (time, presence of additives and concentration) were more relevant than their individual effect, indicating the singularity of each contamination scenario. Long-term contact did not affect mussels, indicating the influence of time to acclimation. Microplastics were not assimilated and retained along food chains, but only biotransferred from prey tissues to predators\' tract, showing the influence of prey contamination on the effectiveness of microplastics biotransference. To evaluate risks in nature, microplastic ingestion was investigated in mussels from the Santos Estuary. Santos Estuary contained microplastics in 75% of sampled mussels, an issue of environmental and human concern. This study illustrated that microplastics impacts on mussels vary with microplastics characteristics, exposure scenario and species vulnerability, highlighting the need for more toxicological and risk evaluation studies.
Os microplásticos (< 5mm) são um dos impactos mais difundidos da sociedade moderna. Aqui, eles foram estudados em ensaios experimentais, considerando diferentes composições de exposição de mexilhões à micro-PVCs. O objetivo foi investigar: sinais fisiológicos de estresse sob exposições aguda e crônica; e transferência, assimilação e retenção de microplásticos em cadeias tróficas. Para avaliar seus potenciais riscos na natureza, a ingestão por mexilhões também foi investigada no Estuário de Santos. As exposições agudas afetaram a fisiologia dos mexilhões, sendo influenciadas pelo tempo e concentração de exposição, e pela presença de aditivos plásticos. Interações entre esses fatores (tempo, concentração e aditivos) foram mais relevantes do que eles individualmente, sugerindo a singularidade dos cenários de poluição. A exposição de longo prazo não afetou os mexilhões, indicando a influência do tempo na aclimatação ao microplástico. O PVC não foi assimilado e retido nas cadeias tróficas, mas biotransferido do tecido das presas para o trato dos predadores, mostrando a influência do estado da presa na efetividade da biotransferência dos microplásticos. Dentre os mexilhões coletados, 75% estavam contaminados, revelando uma importante questão socioambiental. Esse trabalho ilustrou a complexidade dos impactos dos microplásticos para a biota marinha, ressaltando a necessidade de mais estudos sobre seus riscos.

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Osman, Nawal. "Assessment of aflatoxin contamination in infant food supplements used in different feeding patterns". Thesis, University of Surrey, 1995. http://epubs.surrey.ac.uk/804386/.

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25

Shane, Sharon L. "Reported bacterial foodborne outbreaks occurring in institutional settings and group gatherings : United States, 2000 through 2004 /". abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1440932.

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Thesis (M.P.H.)--University of Nevada, Reno, 2006.
"December, 2006." Includes bibliographical references (leaves 90-117). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2006]. 1 microfilm reel ; 35 mm.

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Surendera, Babu Aruna. "Food safety communication in Nevada needs assessment /". abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1433410.

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27

Ruadrew, Sayan. "Characterization of aflatoxin contamination of foods and identification of food components that protect against aflatoxin-mediated toxicity and mutagenicity". Thesis, Glasgow Caledonian University, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687407.

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Aflatoxins (AFs) are a group of mycotoxins produced by moulds of Aspergillus genus which contaminate food commodities of tropical and sub-tropical countries. The aims of this study are to assess the extent of AF contamination of foods in the UK that originated in Asia and to identify components of Thai foods that may protect against the toxicity of AFs. Examination of 12 commercial, dried Asian foods showed that long grain rice, fragrant rice, peanuts, black beans and black pepper contained Aspergillus spp. which were identified as A. parasiticus (afiatoxigenic), A. versicolor, A. ustus, A.niger and A. ochraceus. These commodities contained undetectable AFs. Jasmine brown rice and crushed chilli contained 14.7 and 11.4 IJglkg of AFs, respectively, in the absence of Aspergillus. AFBl, the most toxigenic AFs was detected in crushed chilli (lO.7IJglkg) so Aspergillus was present at some stage of food production, particularly pre-harvest stage. Cross contamination during food processing is one of possible cause of AFs contamination in these commodities. These results indicate direct and indirect risks of exposure to AFs from these products since AFs fOlmation is possible in Aspergillus-contaminated crops and AFs can be carried throughout the food chain. Hence an alternative strategy to mitigate toxicity of ingested AFs is required. One possibility is by using food components to modulate the harm from ingested AFs by altering AF metabolism and mutagenesis. In this study, the effectiveness of the compounds in Thai culinary herb, fingerroot (Boesenbergia rotunda) were investigated. A crude methanol extract (ME) of fingerroot was analysed and found to contain ~ 15 putative flavonoids as major components of which pinocembrin, pinocembrin chalcone, cardamonin, pinostrobin, 4-hydroxypanduratin A and panduratin A were identified by HPLC and LC-MS. The ME significantly inhibited fonnation of mutagenic/carcinogenic metabolite of AFBl (AFB1-epoxide, AFBO) in a cell-free metabolic system (Model 1) and also suppressed mutagenicity of AFBl in Salmonella/microsomal assay (Model 2). These inhibitory properties of the ME might be related to its indigenous flavonoids which could modulate activities of AFB1 -metabolising enzymes (CYPIA2, 3A4). Purified flavonoids (cardamonin, apigenin, pinostrobin) were found to affect AFB 1 toxicity to some extent in both models, but their potencies were much lower than the ME particularly in the Salmonella model and evidence is provided that suggests that Reactive Oxygen Species rather than AFBO are the mutagenic entities in this assay. This also suggests that fingerroot contains effective metabolic modulators that were not identified. Consumption of fmgerroot could provide a combination of potential phytochemicals that protect against aflatoxin-mediated toxicity by altering AF metabolism at the initial stages of enzymatic activation.

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He, Lili Lin Mengshi. "Application of surface enhanced Raman spectroscopy to food safety issues". Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6859.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 23, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Mengshi Lin. Vita. Includes bibliographical references.

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29

Osuagwu, Stanley. "Analyzing Fact Based Preventive Approach to Address Foreign Material Contamination in the Food Industry". Thesis, The George Washington University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10636623.

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Analyzing fact based preventive approach to address foreign material contamination in the food industry is a necessary analysis, focused on using statistical evaluations to analyze the disturbing trend of foreign material food recall in the meat and poultry industry today. Even though recalls due to microbiological contaminations and allergens seem to get more media attention, foreign material meat and poultry food contaminations are also on the rise and the market is starting to show disturbing trends of increasing volumes of products that are recalled due to potential adulteration.

Unfortunately, tighter regulatory oversight and new food safety modernization acts have not demonstrated significant success towards reducing the occurrence of these foreign material food recalls. It appears that the incident rates have remained somewhat flat year over year, but the volume of product that are being destroyed due to extraneous material contaminations continues to show exponential increase.

Food producers cannot continue to conduct business as usual in a world that is constantly changing. They must begin to adapt and invest in technology and in fact based foreign material prevention initiatives, in order to close the disparity in technology between the production equipment and the foreign material detection equipment.

The outcome of my research has suggested that maintaining a status quo to foreign material prevention has not proven successful in limiting recall occurrences in the food industry. The research supports that a switch to fact based prevention approach can yield superior outcomes that are beneficial to both the food manufacturers and food consumers.

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Swanton, Kerry Vivienne. "Food safety and waste water reuse : heavy metal contamination in peri-urban Varanasi, India". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428327.

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Vatanyoopaisarn, Savitri. "Formation of biofilms on stainless steel by Pseudomonas fluorescens and Listeria monocytogenes". Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310957.

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32

Chung, Sunjung. "Effect of Poor Sanitation Procedures on Cross-Contamination of Animal Species in Ground Meat Products". Chapman University Digital Commons, 2019. https://digitalcommons.chapman.edu/food_science_theses/3.

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While the presence of ≥1% of an undeclared species in ground meat generally used as an indicator of intentional mislabeling as opposed to cross-contamination, the actual percent of undeclared species resulting from cross-contamination has not been experimentally determined. The objective of this study was to quantify the effect of sanitation procedures on the crosscontamination of animal species in ground meat products, using undeclared pork in ground beef. Pork (13.6 kg) was processed using a commercial grinder, then one of three sanitation treatments was completed (“no cleaning”, “partial cleaning”, or “complete cleaning”). Next, beef (13.6 kg) was ground using the same equipment. For “no cleaning,” beef was ground immediately after pork without any cleaning step; for “partial cleaning,” the hopper tray was wiped, and excess meat was taken out from the auger; for “complete cleaning,” all parts of the grinder were disassembled and thoroughly cleaned with water and soap. A 100-g sample was collected for each 0.91 kg (2 lb) of beef processed with the grinder and each sanitation treatment was tested twice. Real-time polymerase chain reaction (PCR) was used to quantify pork in ground beef. For “no cleaning,” the first 100-g sample of ground beef run through the grinder contained 24.42 ± 10.41% pork, while subsequent samples contained

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33

RICCI, MARCO. "Design and Validation of a Microwave Device for Food Contamination Real-time Sensing and Imaging". Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2971515.

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34

Cameron, Michelle. "Impact of low-frequency high-power ultrasound on spoilage and potentially pathogenic dairy microbes". Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/597.

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Lim, Kyungwha. "Reduction of spoilage and pathogenic bacteria on beef products by direct and indirect applications of antimicrobial agents /". free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3100061.

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Trickett, Michelle D. "Investigation of environmental microorganisms associated with the intrinsic microbial contamination of an alcohol-free mouthwash". Huntington, WV : [Marshall University Libraries], 2007. http://www.marshall.edu/etd/descript.asp?ref=810.

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37

Delle, Cese Francesca. "EFFECT OF LIQUID CONTAMINATION ON HERMETICITY AND SEAL STRENGTH OF FLEXIBLE POUCHES WITH LLDPE SEALANT". DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1178.

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Flexible packaging is a growing successful market and the majority of flexible package applications are for the food industry. The demand for process optimization and reduced production costs, has led to an increase in flexible packaging. However, fast production lines can result in contamination in the seal area. For flexible food packaging, contamination is considered any food particle or substance trapped in the seal area. Current quality control processes can detect contamination in the seal area, but it is not determined if seal contamination effects seal quality. Oil-based and sodium based snack foods are two common categories that can be packaged on a horizontal flow film and seal (HFFS) flow-wrap machine. The study uses vegetable oil and a salt water solution to simulate the effect of liquid contamination along the T-point of flexible pouches made on an HFFS. The T-point refers to where the fin seal meets the end seal and requires the seal jaw to seal through four layers of film, which is the most difficult point to seal. The study tests a combination of different sealing temperatures and dwell time to determine the optimal sealing condition for a hermetic seal. A quality hermetic seal provides an enclosed seal with no leaks due to successful polymer chain entanglement between the two sealant layers. The different test categories of the study are non-contaminated (control), salt water solution for salt based foods, and vegetable oil for oil-based foods. Given the test parameters of the study, 140⁰C sealing temperature and 0.3 seconds dwell time are considered to be the optimal sealing condition for all three test categories. For Phase 1 of the study, salt water has a lower hermeticity pass rate compared to vegetable oil and non-contaminated seals. In addition, the effect of refrigerated storage temperature and ambient storage temperature did not show to be significant for any of the test categories. However, refrigerated conditions showed a higher hermeticity pass rate, but it was not statistically different. The findings for seal strength indicated no test category had higher or lower seal strength over the 14 day test period. Overall, the study shows there is no effect of liquid contaminant on hermeticity and seal strength for flexible film with LLDPE sealant layer.

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38

Dixon, Lorraine Louise. "Microbiological Quality of Toroi: A Māori food delicacy". The University of Waikato, 2007. http://hdl.handle.net/10289/2229.

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A study was undertaken to determine the food safety of the fermented Māori delicacy, Toroi. Ten batches of Toroi were prepared by a commonly used traditional method that consisted of boiling the vegetable component, either watercress or puha, and combining it with chopped mussel flesh. The mixture was cooled and then stored in a refrigerator for up to eight months to allow natural fermentation to take place. All ingredients were sourced from retail outlets. The Toroi was examined at intervals over eight months for a range of pathogens (seven in all) that have been related to incidents of food poisoning in ready-to-eat foods in New Zealand. The survival of a faecal contamination indicator, the laboratory grown strain Escherichia coli NZRM 916, was mapped over eight months. Two strategies to prevent the growth of Listeria monocytogenes in Toroi were also investigated. Only one of the seven pathogens sought was recovered from any sample. This pathogen was Bacillus cereus, a spore-former known to be associated with vegetables. All batches contained B. cereus on the day of preparation but after two weeks refrigerated storage there was no further recovery from any sample. There was a very low incidence of natural E. coli in the Toroi, consistent with levels permitted in mussels sold in retail outlets. The laboratory grown strain, E. coli declined substantially over two months and was not recovered from any samples at eight months. A laboratory grown strain of Listeria monocytogenes, (L70) was added to Toroi and grew well with an increase in concentration of about seven-fold, over 19 days storage in a refrigerator. A bacteriocin producing lactic acid bacterium, Lactobacillus sake Lb706, was added in combined culture with L. monocytogenes to Toroi. It was found that at least 5 x108 L. sake cells were required as an inoculum to ensure elimination of L. monocytogenes from the Toroi. When a purified bacteriocin; nisin, was added, a concentration of 10 mg g-1 in the Toroi was required to eliminate L. monocytogenes. The inhibition study results suggest that unacceptably high inocula or purified bacteriocin would be required to prevent the growth of L. monocytogenes in Toroi. The results of this suggest that Toroi be prepared from mussels either purchased from a retail outlet or harvested from sites known to be free from contamination. Toroi should be safe to eat if prepared carefully, chilled promptly and thoroughly and allowed to ferment for at least two weeks. In addition, care should be taken to maintain Toroi at refrigerated temperatures until it is eaten.

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39

Emara, Hamdy Aly. "Production of aflatoxin by Aspergillus parasiticus and its control". Thesis, University of Stirling, 1996. http://hdl.handle.net/1893/3461.

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The aim of the present work was to investigate aflatoxin levels in various food commodities and to study its production by Aspergillus parasiticus in culture to find out the possible ways to control it. Of 40 food samples collected from Abha region, Saudi Arabia, only 25% were contaminated with aflatoxins. Oil-rich commodities had the highly contaminated commodities by fungi and aflatoxins while spices were free from afatoxins. The optimal pH for the growth of A. parasiticus and its productivity of aflatoxin B, was found at 6.0, while the best incubation conditions were found at 30°C for 10 days. D-glucose was the best carbon source for fungal growth, as well as aflatoxin production. Corn steep liquor, yeast extract and peptone were the best nitrogen sources for both fungal growth and toxin production. (NH4)2HPO4 (1.55 gL-1) and NaNO2 (1.6 gL-1) reduced fungal growth and toxin production with 37.7% and 85%, respectively. Of ten amino acids tested, asparagine was the best for aflatoxin B, production. Zn2+ and Co2+ supported significantly both fungal growth, as well as aflatoxin B, production at the different tested concentrations. Zn2+ was effective when added to A. parasiticus growth medium at the first two days of the culture age. The other tested metal ions gave variable effects depending on the type of ion and its concentration. Water activity (a ) was an important factor controlling the growth of A. parasiticus and toxin production. The minimum aW for the fungal growth was 0.8 on both coffee beans and rice grains, while aW, of 0.70 caused complete inhibition for the growth and aflatoxin B, production. H202 is a potent inhibitor for growth of A. parasiticus and its productivity of toxins. Incubation with NaHCO3 and C6H5000Na converted aflatoxin B, to a water-soluble form which returned to aflatoxin B, by acid treatment. Black pepper, ciliated heath, cuminum and curcuma were the most inhibitory spices on toxin production. Glutathione, quinine, EDTA, sodium azide, indole acetic acid, 2,4-dichlorophenoxy acetic acid, phenol and catechol were inhibitory for both growth, as well as, aflatoxin B, production. Stearic acid supported the fungal growth and decreased the productivity of AFBI gradually. Lauric acid is the most suppressive fatty acid for both fungal growth and aflatoxin production, but oleic acid was the most potent supporter. Vitamin A supported the growth but inhibited aflatoxin B, production. Vitamins C and D2 were also repressive particularly for aflatoxin production. The present study included determining the activities of some enzymes in relation to aflatoxin production in A. parasiticus culture during 20 days. Glycolytic enzymes and pyruvate-generating enzymes seems to be linked with aflatoxin B, production. Also, pentose-phosphate pathway enzymes may provide NADPH for aflatoxin B, synthesis. The decreased activities of TCA cycle enzymes particularly from 4th day of growth up to 10th day were correlated with the increase of aflatoxin B, production. All the tested enzymes as well as aflatoxin B, production were inhibited by either catechol or phenol.

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40

Skillington, Pauline. "Migration of chemicals through coated paperboard for food contact packaging". Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/752.

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Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Chemistry in the Faculty of Applied Sciences at the Cape Peninsula University of Technology
Paperboard made from recycled fibres is being used more frequently in direct food packaging applications, in addition to its use as secondary and tertiary packaging. However, recent research has shown that there is a risk that harmful chemicals may migrate from the paperboard into the food. The simplest approach to reducing the migration of these contaminants is the use of barrier films. The barrier efficiencies of these various films can be examined by means of a migration test into a food simulant, followed by extraction in a suitable solvent. The extract can then be analysed by chromatographic techniques such as gas chromatography mass spectrometry (GC-MS) to determine the concentration of the specific contaminants. However on a production level, the availability of this type of highly specialised equipment is limited. A simple, cost effective method is needed to evaluate the barrier properties to specific chemical contaminants. The Heptane Vapour Transmission Rate (HVTR) test is a permeation test method for use at quality control level to determine barrier properties to the migration of organic vapours. The first part of the study focussed on establishing a universal correlation between HVTR and specific migration of diisobutyl phthalate (DiBP), dibutyl phthalate (DBP) and diethylhexyl phthalate (DEHP) that would be applicable to any type of functional barrier. However, experimental data demonstrated this was not possible as the correlation factor linking HVTR to specific migration was largely dependent on the type and morphology of the coating considered. The initial objective of the study was reconsidered in favour of building individual models specific to the nature of the coating and substrate considered. A correlation between HVTR and specific migration of DiBP, DBP and DEHP for a polyvinylidene chloride (PVDC) barrier polymer was constructed by varying the applied coating weight. The vapour transport mechanism for the HVTR test and the specific migration test were found to differ, showing that a direct correlation between HVTR and the specific migration was again not possible. However, an indirect correlation could be made. The HVTR method gives an indication of film integrity, whereas the coating weight could be used as an indicator of the specific migration. The correlation between the coating weight and the specific migration yielded an equation that can be used to calculate the specific migration through the PVDC barrier polymer, provided the quantity of the chemical contaminant originally present in the paperboard was known. This equation was specific to the type of barrier polymer, the specific chemical contaminant as well as the intended shelf-life of the food product to be packaged in the paperboard.

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41

Yeap, Jia Wei. "Inactivation of a Human Norovirus Surrogate by Chlorine Dioxide Gas and Prediction of Human Norovirus Contamination by a Fecal Indicator System". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366640143.

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42

Rodgers, Svetlana. "Development of a bio-preservation method for extended shelf-life cook-chill systems". Thesis, View thesis, 2003. http://handle.uws.edu.au:8081/1959.7/23237.

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Extended shelf-life cook-chill meals can pose a potential risk of botulism if they are subjected to a temperature abuse. Spores of group II non-proteolytic Clostridium botulinum can survive the mild heat treatment typically given to these products and can grow at refrigeration temperatures. To circumvent this safety issue, existing preservation methods can either affect the sensory properties of these foods or damage their image. Therefore, additional natural preservation hurdles are needed. Thus, the aim of this study was to develop a novel bio-preservation method based on the principle of antibiosis between protective cultures (PCs) and C. botulinum. Consequently, the objectives were to select effective anti-botulinal cultures and study their inhibition pattern in microbiological media and foods, identify the conditions for effective inhibition and the nature of the antibiosis. This research demonstrates for the first time that the bacteriocinogenic protective cultures inoculated at high levels had an anti-botulinal effect in a range of commercial cook-chill products, which supported active growth of non-proteolytic C. botulinum. The protocol for commercial application of the protective cultures was developed.

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43

Hahn, Celia. "Review of arsenic contamination and human exposure through water and food in rural areas in Vietnam". Doctoral thesis, Eigenverlag des Forums für Abfallwirtschaft und Altlasten e.V, 2015. https://tud.qucosa.de/id/qucosa%3A29429.

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The Red River Delta in Vietnam is one of the regions whose quaternary aquifers are polluted by arsenic. Chronic toxification by arsenic can cause severe illnesses such as cancer, skin lesions, developmental defects, cardiovascular and neurological diseas-es, and diabetes. In this study, a food processing craft village in the Red River Delta was investigated regarding the potential risk faced by the population due to arsenic. The potential sources of arsenic are the groundwater, the crops grown in the sur-roundings, and animal products from local husbandry. However, the occurrence of arsenic in nature is variable, and its bioavailability and toxicity depend very much on its specification: trivalent compounds are more toxic and often more mobile than pen-tavalent compounds, while inorganic species are generally more toxic than organic ones. Local conditions, such as the redox potential, strongly influence its specification and thus potential bioavailability. The introduction to this work elucidates the key factors which potentially cause human exposure to arsenic: the geological setting of the study area, land and water use pat-terns, and the current state of research regarding the mobilization, bioavailability and plant uptake of arsenic. Although the study area is located in a region where the groundwater is known to be moderately contaminated by arsenic, the level of arsenic in the groundwater in the village had not previously been determined. In this study, water use in the village was examined by a survey among the farmers and by water analyses, which are present-ed in the following chapters. Four main water sources (rain, river, tube well and a pub-lic municipal waterworks) are used for the different daily activities; the highest risk to human health was found to be the bore well water, which is pumped from the shallow Holocene aquifer. The water from the bore wells is commonly used for cleaning and washing as well as to feed the animals and for food processing. Products like noodles and rice wine were examined as well as local pork and poultry. Vegetables from the gardens and rice plants from the surrounding paddy fields were sampled and ana-lyzed. All plants were found to have accumulated arsenic, leafy vegetables showing the highest arsenic concentrations. The results are discussed and compared, and conclusions are drawn in the last part. The reducing conditions in the paddy fields are likely to have a strong influence on arsenic uptake in rice plants and on transport to the aquifer. The installation of a wastewater treatment plant under the research project INHAND, which was funded by the BMBF German Ministry of Education and Research, led to lower arsenic concen-trations in the groundwater. Soaring industrialization, the growing population, and the consumers’ changing behav-ior will widely affect land and water use and hence the potential mobilization of arse-nic. In order to mitigate further human exposure to arsenic, wastewater needs to be treated and the reducing conditions in the rice fields need to be decreased by means of enhanced cultivation methods.:Abstract III Zusammenfassung V Acknowledgements VII Contents IX List of abbreviations XIII List of tables XVII 1 Scope of this work 1 2 Introduction 2 2.1 Geographical and geological setting of the study area 2 2.2 Hydrological situation 5 2.2.1 Surface water 5 2.2.2 Impact of human activities on surface water quality and distribution 6 2.2.3 Hydrogeology 7 2.3 Arsenic occurrence 7 2.3.1 Arsenic toxicity 8 2.3.2 Risk potential of arsenic in diet 10 2.4 Arsenic contamination in the groundwater resources of the Red River Delta 11 2.4.1 Occurrence and origin of arsenic in the Red River Delta 12 2.4.2 Mobilization processes 13 2.4.3 As mobilization in paddy fields 15 2.5 Arsenic occurrence in daily rural activities 16 2.5.1 Arsenic in soil 17 2.5.2 Arsenic in drinking water 19 2.5.3 Phytoaccumulation: Current state of research 20 2.5.4 Bioavailablity 22 2.5.5 Arsenic uptake in rice plants 23 2.5.6 Arsenic in meat and animal products 26 2.5.7 Arsenic uptake in golden apple snails 27 2.5.8 Processing: Wine and noodles 28 2.5.9 Arsenic concentrations in wastewater, activated sludge and digestate 29 2.6 Iron and manganese in the nutrient chain 30 2.7 Land and water use in the Red River Delta 31 2.7.1 Historical and political aspects of rural development in Vietnam 33 2.7.2 Craft villages in the Red River Delta 34 3 Materials and methods 36 3.1 Soil sample analyses 36 3.2 Well sampling 37 3.3 Wastewater and sludge analyses 37 3.4 Food analyses 38 3.5 Site visit and field observations 39 3.6 Questionnaire 39 4 Results 40 4.1 Soil samples 40 4.1.1 Total arsenic and total heavy metal concentrations 40 4.1.2 Sequential fractionation procedure 41 4.2 Arsenic in the water cycle in Dai Lam 43 4.2.1 Groundwater analyses 43 4.2.2 Water use in Dai Lam 47 4.2.3 Wastewater in Dai Lam 50 4.3 Arsenic in sewage sludge 51 4.4 Arsenic in manure samples 52 4.5 Arsenic in food samples 52 4.5.1 Rice 52 4.5.2 Arsenic in leaf vegetables 53 4.5.3 Arsenic in poultry products 56 4.5.4 Arsenic in pork samples 57 4.5.5 Arsenic in snails 57 4.6 Economic and demographic development potential 58 5 Discussion 61 5.1 Soil samples 61 5.2 Groundwater samples 62 5.2.1 High arsenic concentrations 62 5.2.2 Strong temporal and spatial variation 63 5.2.3 Weak correlation between measured parameters 69 5.3 Wastewater and sewage sludge 70 5.4 Pig manure 71 5.5 Daily exposure to As from dietary intake 71 5.6 Effects of land and water use on water quality and public health 76 5.7 Against the background of the transition economy 77 6 Conclusion 80 7 Perspectives (further work) 85 8 References 86 9 Annex 110

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44

Hahn, Celia. "Review of arsenic contamination and human exposure through water and food in rural areas in Vietnam". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-201053.

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The Red River Delta in Vietnam is one of the regions whose quaternary aquifers are polluted by arsenic. Chronic toxification by arsenic can cause severe illnesses such as cancer, skin lesions, developmental defects, cardiovascular and neurological diseas-es, and diabetes. In this study, a food processing craft village in the Red River Delta was investigated regarding the potential risk faced by the population due to arsenic. The potential sources of arsenic are the groundwater, the crops grown in the sur-roundings, and animal products from local husbandry. However, the occurrence of arsenic in nature is variable, and its bioavailability and toxicity depend very much on its specification: trivalent compounds are more toxic and often more mobile than pen-tavalent compounds, while inorganic species are generally more toxic than organic ones. Local conditions, such as the redox potential, strongly influence its specification and thus potential bioavailability. The introduction to this work elucidates the key factors which potentially cause human exposure to arsenic: the geological setting of the study area, land and water use pat-terns, and the current state of research regarding the mobilization, bioavailability and plant uptake of arsenic. Although the study area is located in a region where the groundwater is known to be moderately contaminated by arsenic, the level of arsenic in the groundwater in the village had not previously been determined. In this study, water use in the village was examined by a survey among the farmers and by water analyses, which are present-ed in the following chapters. Four main water sources (rain, river, tube well and a pub-lic municipal waterworks) are used for the different daily activities; the highest risk to human health was found to be the bore well water, which is pumped from the shallow Holocene aquifer. The water from the bore wells is commonly used for cleaning and washing as well as to feed the animals and for food processing. Products like noodles and rice wine were examined as well as local pork and poultry. Vegetables from the gardens and rice plants from the surrounding paddy fields were sampled and ana-lyzed. All plants were found to have accumulated arsenic, leafy vegetables showing the highest arsenic concentrations. The results are discussed and compared, and conclusions are drawn in the last part. The reducing conditions in the paddy fields are likely to have a strong influence on arsenic uptake in rice plants and on transport to the aquifer. The installation of a wastewater treatment plant under the research project INHAND, which was funded by the BMBF German Ministry of Education and Research, led to lower arsenic concen-trations in the groundwater. Soaring industrialization, the growing population, and the consumers’ changing behav-ior will widely affect land and water use and hence the potential mobilization of arse-nic. In order to mitigate further human exposure to arsenic, wastewater needs to be treated and the reducing conditions in the rice fields need to be decreased by means of enhanced cultivation methods.

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45

Ding, Yajun Mustapha Azlin. "Transfer of Listera monocytogenes and Escherichia coli 0157:H7 during food processing". Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6071.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on Oct. 7, 2009). Thesis advisor: Dr. Azlin Mustapha. Includes bibliographical references.

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46

Cooper, Robin M. "Development of a Rep-PCR screening assay for enterotoxigenic Bacillus spp. in naturally contaminated food". Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1306386.

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Several powdered food products were screened using repetitive element palindrome PCR (rep-PCR) for the presence of enterotoxin producing species of Bacillus. Samples from these products were screened by being placed into a tryptone-peptoneglucose-yeast enrichment medium (TPGY), heat-treated, and shake-incubated. DNA was extracted using a modification of established protocol, leading to the development of an optimized method for each food system. Purified DNA was amplified through rep-PCR using extragenic sequence-targeting primers and optimized for each food product. Amplified PCR products were analyzed electrophoretically and viewed using an ultraviolet photodocumentation system. Bacillus cereus positive control DNA fingerprints were compared to banding patterns from enriched food samples, revealing the presence of the typical diagnostic 1,230 bp band in non-fat dry milk (NFDM). Restriction Fragment Length Polymorphism (RFLP) with Alu I restriction enzyme was performed on the 1230 bp diagnostic band from NFDM and displayed a profile consistent with Bacillus cereus positive control. RPLA (Reverse Passive Latex Agglutination) and BDE ELISA (Bacillus Diarrhoeal Enterotoxin Enzyme Linked Immunosorbent Assay - Tecra Diagnostics) confirmed the presence of HBL and NHE enterotoxin production in NFDM, Coffee creamer, infant milk formula, and two lecithin samples.
Department of Biology

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47

Nigar, Meher. "Studies on the interaction between arsenic (As) and rice varieties which differ in arsenate (As(V)) tolerance". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=33413.

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48

Lambrechts, Andre Albertus. "The efficacy of sanitation on microbiological hazards in ready-to-eat food outlets from selected primary manufacturers in Gauteng Province, South Africa". Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/779.

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Dissertation submitted in fulfilment of the requirements for the degree Master of Technology: Environmental Health in the Faculty of Applied Sciences at the Cape Peninsula University of Technology, 2011
The retail sector in South Africa is increasingly evolving into a dynamic industry, driven by changes in technology, saturating markets and globalisation. A major phenomenon in South Africa has been the evolution of hypermarkets, which sell large quantities of almost all consumer goods on a self-service basis. The South African consumers are becoming increasingly health conscious and, as such, the demand for wellness foods, health and convenience food has escalated. Convenience foods are expected to remain popular with consumers and supermarkets and will therefore increase the amount of ready-to-eat food items offered. As the retail industry has changed over the last two decades, so has the epidemiology of foodborne illnesses, with an increase in the incidence of bacterial infections caused by emerging organisms. In addition, there are certain food safety issues specifically associated with ready-to-eat foods. In recent years, incidences of enteric diseases associated with meat consumption have risen. The emergence of several new foodborne diseases has led to an increased focus attention on the issue of food safety by consumers and the industry. The most commonly implicated foods in these disease outbreaks have been meat and dairy products. The microbial load of eight convenience food manufacturing plants was determined by firstly sampling stainless steel food contact surfaces after they had been cleaned and sanitised at the end of a day‘s shift. The samples were analysed for Total Plate Count (TPC), Escherichia coli, Salmonella species and Staphylococcus aureus and Listeria. The results showed that 59 % of the total areas sampled for TPC failed to comply with the legal requirements for food surfaces specified in the South African Health Act (< 100 cfu.cm-2). Listeria was detected in 23 % of the samples taken and E.coli was found in 1.3 % of the samples, while S. aureus was not detected in any of the samples. Fifty percent of the plants applied conventional cleaning methods for cleaning and sanitation and the remaining 50 % used the low-pressure foam (LPF) method. The bacterial results of the two cleaning methods were statistically compared and a statistically significant difference (P ≤ 0.05) was found between the TPC means of the cleaning methods after cleaning. No statistically significant difference (P > 0.05) was found in terms of the Listeria species counts after both cleaning processes. The LPF method proved to be the superior cleaning option for reducing TPC counts. Secondly surface samples were collected from washed and sanitised dominant hands of food handlers and analysed for the presence of total plate counts, S. aureus and E. coli. The study aimed to evaluate the efficacy of hand washing practices and sanitation before commencing work. A total of 230 samples were collected, involving 100 % of the food handlers in selected convenience food outlets. The highest bacterial count taken from handswas 7.4 x 10-3 cfu.cm-2 and the lowest showed no detectable growth. Forty percent of the TPC analysed complied with the legal limit of < 100 cfu.cm-2 and only 18 % of the food handlers had no detectable bacteria present on their hands. One hand sample tested positive for E. coli, which is generally viewed as an indication of faecal contamination. S. aureus could not be detected on the hands of any of the food handlers. The results of this study indicated that hand hygiene is unsatisfactory and underlined the importance of further training to improve food handlers‘ knowledge of good hand washing practices. The study also aimed to present data on the food hygiene knowledge and practices of food handlers based on a representative sample from convenience food outlets in the Gauteng area. The management, as well as food handlers, were interviewed without prior announcement and managers were interviewed prior to starting their shifts, followed by food handlers, after they had passed through the change room and hand wash facilities. Although the majority of food handlers adhered to basic hygiene principles, the results highlighted a need for proper and continuous training in hygiene practices, not only for food handlers, but also for management. Furthermore, all food handlers should adhere to a formal cleaning schedule and specific courses should be planned for food handlers. Most training is done away from the workplace and the workers might find it difficult to translate theory into practice. Although food safety training programmes are essential, behavioural changes will not occur merely as a result of having received training but rather continuous development of food handlers. In conclusion, the popularity of convenience food is bound to increase with the growing appeal for modern foods. Consumers in South Africa nowadays demand good quality and safe products at a reasonable cost. Due to continuous time constraints, convenience food is the food of the future for the working mother. It is clear that managing foodborne disease is a challenge and an economic problem subject to various constraints. Food safety has too often become a hit-or-miss gamble, with parents obliged to roll the dice when it comes to the safety of their children‘s food and consumers in general. The food industry therefore needs to improve food safety processes to prevent the contamination of foods and use methods to ensure safe food for consumers. Better training, more testing and better methods of tracking food must be utilised to verify that the processes are working. This study endeavoured to add to the understanding and improvement of hygiene processes as well as food handlers‘ practices in the convenience food industry in the Gauteng Province.

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49

Chiang, Yun-en G. "Crisis communication and image repair from a cultural aspect a case study of King Car's image repair program in Taiwan /". Muncie, Ind. : Ball State University, 2009. http://cardinalscholar.bsu.edu/698.

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50

McKinley, Mary Beth. "Addressing Contaminants in Traditional Foods in Alaska: Environmental Justice Framing and Policy Approaches". The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-05142007-071823/.

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The transport of contaminants to the Arctic and their presence in traditional foods in the region is causing concern about potential adverse health impacts resulting from exposure to these globally-borne chemicals. In this study, ten stakeholders in the issue of contaminants in traditional foods in Alaska were interviewed to determine how they define the problem, and in doing so, to determine if they perceive that the situation constitutes an environmental injustice for Alaska Natives. The interview transcripts were analyzed using five sub-frames of the environmental justice framework: distributive justice, procedural justice, indigenous rights, corrective justice, and ecological sustainability. The interview responses suggest that, viewed through five sub-frames of environmental justice (EJ), Alaska Natives do face an environmental injustice. In particular, Alaska Natives face disparate cultural impacts at the hands of contaminants and lack adequate opportunities for procedural involvement. The findings presented in this paper point to three solutions to the problem: 1) Establish a U.S. Arctic Contaminants Program to collaboratively study the situation in Alaska and to provide education to impacted populations, 2) Enact new comprehensive, enforceable, precautionary U.S. laws that govern and regulate chemicals, and 3) Extend global policies that phase out chemicals and support ecologically sustainable practices. Additionally, this professional paper, done to help support the work of the Alaska Community Action on Toxics (ACAT), offers suggestions for strategies that ACAT can use in their activism. These strategies consider how to best use the various EJ frames to effectively communicate with stakeholders (other activist groups and government entities) about the problems and solutions for dealing with the threat that contaminants in traditional foods pose to Alaska Natives.

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