Browsing by Subject "Food Safety"

Now showing 1 - 7 of 7
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    Application of restaurant inspection data analysis to increase assurance of food safety.
    (2012-05) Petran, Ruth Lindenthal
    Foodborne illness affects 48 million Americans annually with the majority of reported foodborne outbreaks due to food prepared and served by restaurants. Food safety practices at restaurants are verified via periodic inspections by health department personnel. With millions of such inspections conducted every year, concentrating on the most frequently identified risk factors could focus interventions where they will have the most impact. This would be particularly beneficial for restaurant chains with establishments across the country. Compared in this study were recent health department inspections in Minnesota and Arizona that had been performed at restaurants known to have had confirmed outbreaks to matched control restaurants that did not have outbreaks during the same time period. No overall relationship to foodborne illness risk factors was demonstrated. However, a set of violations more likely to be associated with outbreak restaurants was identified. These violations likely represented a lack of overall control of food safety processes in the outbreak restaurants. There were differences in the specific violations identified between the two states, most likely attributable to the high variability in inspection approaches among different health department jurisdictions. The results highlight the need for a more consistent, nationwide approach to restaurant inspections than exists currently and suggest several approaches to improve the use of inspection data to reduce foodborne illness rates.
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    Ecology and Epidemiology of Campylobacter Jejuni In Broiler Chickens
    (2019-06) Hwang, Hae Jin
    Campylobacteriosis, predominantly caused by Campylobacter jejuni, is a common, yet serious foodborne illness. With consumption and handling of poultry products as the most important risk factor of campylobacteriosis, reducing Campylobacter contamination in poultry products is considered the best public health intervention to reduce the burden and costs associated with campylobacteriosis. To this end, there is a need to improve our understanding of epidemiology and ecology of Campylobacter jejuni in poultry. The overall goal of this dissertation is to answer knowledge gaps regarding Campylobacter ecology and epidemiology in broiler chickens with an emphasis on the pre-harvest components of the broiler production system. The objectives included: (1) to assess current interventions and control measures practiced by the U.S. broiler industry to reduce Campylobacter contamination on broiler chicken products; (2) to investigate indirect selective pressures responsible for the persistence of fluoroquinolone-resistant Campylobacter jejuni in broiler chickens; and (3) to describe the temporal changes in broiler litter bacterial microbiota with respect to bird age, flock cycle, antibiotic use and presence of Campylobacter on farms. For the first objective, we surveyed key stakeholders of the U.S. broiler industry, including poultry veterinarians, farm managers and processing plant managers. The survey respondents reported the use of various pre- and post-harvest interventions that are recommended by the USDA-FSIS to decrease Campylobacter contamination in broiler chickens and on carcasses. Yet, the survey results also revealed the lack of understanding of Campylobacter epidemiology among the respondents, indicating that further education and training programs are necessary to improve understanding of Campylobacter among the key stakeholders which can lead to a reduction of Campylobacter contamination and improvement in food safety. To investigate indirect selective pressures allowing persistence of Campylobacter jejuni in broiler chickens, we tested two hypotheses: limited bioavailability in poultry and activity of microcin B17. However, we found that the hypotheses tested were unlikely to be responsible for the persistence of fluoroquinolone-resistant Campylobacter jejuni despite the lack of fluoroquinolone use in the industry. Lastly, we investigated the temporal changes in the broiler litter microbiota by sampling seven commercial broiler farms over two flock cycles. We found that flock cycle and age of bird were two significant farm variables driving the bacterial diversity and composition of the litter microbiota. Additionally, when the litter bacterial microbiota was compared between Campylobacter-positive and Campylobacter-negative samples, a lower abundance of Lactobacillus was observed among the positive samples. Overall, the work presented in this dissertation demonstrates collective efforts to improve our understanding of Campylobacter jejuni in broiler chickens using multidisciplinary approaches.
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    Food Safety Plans: Opportunities and Barriers for Small MN Fruit and Vegetable Producers
    (Hubert H. Humphrey School of Public Affairs, 2014-07-08) Korslund, Karen
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    Food-Borne Illness and Farmers Markets Accepting Food Stamps
    (2016-05) Nguyen, Ngoc
    I study the relationship between farmers markets accepting food stamps (SNAP) and food-borne illness in the United States. Using a state-level panel data set that covers 50 states and the District of Columbia for 2004-2013, I find no relationship between SNAP-accepting farmers markets per capita and reported outbreaks of food-borne illness and cases of food-borne illness per capita. When including SNAP redemption value at farmers markets as a control variable, I find a negative and statistically significant relationship between farmers markets accepting food stamps per capita and reported C. perfringens outbreaks per capita for 2009-2013. When excluding SNAP redemption value at farmers markets from the control variables, I find positive and statistically significant relationships between farmers markets accepting food stamps per capita and reported staphylococcus aureus outbreaks, as well as reported Salmonella enterica outbreaks, per capita. The falsification and placebo tests indicate that these relationships are likely to be spurious.
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    Minnesota State Fair Animal Health and Livestock Emergency Plan
    (2012-04) Mehlenbacher, Shelley; Goldsmith, Timothy; Minicucci, Larissa; Goodrich, Mark; Hagerty, Tom
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    Operation Guidance Manual for Harvest Facilities during FAD/EDI Investigations
    (2015-10) Goldsmith, Timothy; Mahero, Michael; Davies, Peter
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    Produce Safety in the United States: Epidemiological Trends and Risk Management Utilizing a Novel Screening Method for Shiga-Toxin Producing E. coli and Salmonella in Irrigation Water
    (2019-12) Wu, Yan
    Despite significantly improved technologies in food science and public health and tremendous efforts being put by governments to ensure food safety, foodborne outbreaks are still abundant worldwide. Produce products have been frequently implicated in foodborne illness outbreaks in recent years due to changes in consumer demands, consumption habits and production practices. A better understanding on epidemiology changes of produce outbreaks is needed to evaluate current risks associated with produce supply chain and to understand safety regulations regarding produce safety. In addition, it is evident that water used in produce production plays an important role in potentially introducing microbial contaminations. Therefore, its risk management is crucial for safety assurance of the produce supply chain. The goal of this thesis research is to analyze the epidemiological trends of produce outbreaks and to improve the risk management of microbial quality of irrigation water. It summarizes the changing epidemiology of produce outbreaks in the United States from 1998-2007, establishes the baseline to further evaluate the potential impact from the recently implemented Food Safety Modernization Act (FSMA). The study also describes the development, optimization, and evaluation of a novel selective medium for sensitive enrichment and screening of Shiga-toxin producing E. coli and Salmonella in irrigation water. The developed enrichment-indicator system meets the increasing demand of method for multi-pathogen enrichment and detection in a single assay format allowing cost effective detection of STEC and Salmonella within 24 hours.