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Regulatory Disclosure Policies And Potential Induced Changes In Behavior: An Outcome Evaluation Of Santa Clara County’S Enhanced Food Safety Program Elements, Christian Cruz Apr 2019

Regulatory Disclosure Policies And Potential Induced Changes In Behavior: An Outcome Evaluation Of Santa Clara County’S Enhanced Food Safety Program Elements, Christian Cruz

Master's Projects

Despite countless advances in food microbiology and public health regulations, foodborne illness continues to be a major strain on public health outcomes and a costly economic burden. In the United States, many agencies are responsible for ensuring the quality of food, both domestically produced and imported. States and localities are delegated the responsibility of identifying and ensuring sound practices in the latter stages of the food production process, namely the retail distribution of food products to consumers.

Regulatory policies across the nation have only recently incorporated the evidenced-based principles of hazard risk management (Law, 2003). Still, food-related acute gastrointestinal illnesses ...


An Environmental Approach To Food Safety Assessment Using Artisan Cheese And Fresh Produce As Model Systems, Marie Limoges Jan 2019

An Environmental Approach To Food Safety Assessment Using Artisan Cheese And Fresh Produce As Model Systems, Marie Limoges

Graduate College Dissertations and Theses

This dissertation examined recently issued regulatory standards using cheese and produce as model systems. FDA's 2015 Domestic and Imported Cheese and Cheese Products Compliance Program Guidelines (CPG) E. coli standards on cheese safety, and the extent to which these standards affect domestic and imported cheese commerce, was assessed. Results from FDA's Domestic and Imported Cheese Compliance Program for samples collected between January 1, 2004 and December 31, 2006 were analyzed. Of 3,007 cheese samples tested for non-toxigenic E. coli, 76% (2,300) of samples exceeded 10/g, FDA's target for regulatory activity. In cheese samples containing ...


Influence Of Long-Term Survival On Resistance Of Salmonella Enterica Serovar Typhimurium And Escherichia Coli O157:H7 To Physical Or Chemical Food Processes, Fei Wang Jan 2017

Influence Of Long-Term Survival On Resistance Of Salmonella Enterica Serovar Typhimurium And Escherichia Coli O157:H7 To Physical Or Chemical Food Processes, Fei Wang

Graduate Theses and Dissertations

Under adverse conditions in the natural environment or in food processing facilities bacteria may enter a long-term-survival (LTS) phase and maintain a stable concentration of viable cells for months or years. In this LTS phase, pathogens may become resistant to antimicrobial processes that would typically inactivate them in the exponential- or stationary phase of their life cycle. In this regard, the resistance of LTS phase Salmonella enterica serovar Typhimurium, Salmonella PT 30 and Escherichia coli O157:H7 to ultraviolet (UV) radiation, desiccation or cinnamaldehyde in model systems and in food products was investigated. Exponential-, stationary, and LTS phase cells were ...


Modeling For Thermal Resistance Of Non-O157 Shiga Toxin Producing Escherichia Coli In Ground Beef, Jagpinder S. Brar Dec 2016

Modeling For Thermal Resistance Of Non-O157 Shiga Toxin Producing Escherichia Coli In Ground Beef, Jagpinder S. Brar

Open Access Dissertations

Predictive models in microbiology are used for estimating the growth or survival of microorganism in a set of environmental conditions. A validated predictive model provides an alternative to extensive survival and shelf life studies. In this study, a predictive inactivation model for non-O157 shiga toxin producing Escherichia coli (STEC) in ground beef was developed. Six strains of non-O157 STEC; E. coli O26:H1, E. coli O45:H2, E. coli O103:H2, E. coli O111:H8, E. coli O121:H9, and E. coli O145: nonmotile, has similar pathogenicity as E. coli O157:H7 and can cause serious food borne illnesses. These ...


The Effects Of Using Cinnamon Leaf And Bark Essential Oils On Listeria Monocytogenes (L.M.), Salmonella Typhimurium (S.T.), In Model System, Strawberry Shake And Fresh Celery, And Sensory & Shelf Life Studies, Wafaa Brnawi Dec 2016

The Effects Of Using Cinnamon Leaf And Bark Essential Oils On Listeria Monocytogenes (L.M.), Salmonella Typhimurium (S.T.), In Model System, Strawberry Shake And Fresh Celery, And Sensory & Shelf Life Studies, Wafaa Brnawi

Theses and Dissertations

Essential oils derived from the bark and leaves of the cinnamon plant have long been used as natural preservatives and flavoring agents in different types of foods. In this study, we evaluated the antimicrobial effects of cinnamon essential oils (CEOs), obtained from cinnamon leaf or bark, against two foodborne pathogens i.e., Salmonella Typhimurium (S.T.) and Listeria monocytogenes (L.m.). Two different concentrations of microbial loading were used i.e.,109 and 104, cultured in nutrient media broth, strawberry shakes, and on celery sticks. Both CEOs of leaf and bark at 0.5% and 1% were found to completely ...


Enzymatic Digestion Improved Bacteria Separation From Leafy Green Vegetables, Danhui Wang Jul 2016

Enzymatic Digestion Improved Bacteria Separation From Leafy Green Vegetables, Danhui Wang

Masters Theses

An effective and rapid method for the separation of bacteria from food matrix remains a bottleneck for rapid bacteria detection for food safety. Bacteria can strongly attach to the food surface or internalize within the matrix which makes their isolation extremely difficult. Traditional methods of separating bacteria from foods routinely involve stomaching, blending and shaking, however these methods may not be efficient at removing all the bacteria from complex matrices. Here, we investigate the benefits of using enzyme digestion followed by immunomagnetic separation to isolate Salmonella from spinach and lettuce. Enzymatic digestion using pectinase and cellulase was able to break ...


Microbial Safety, Shelf Life Stability, Quality Preservation, And Consumer Acceptance Of Vacuum-Infused, Irradiated Chicken Breast Meat Treated With Natural Plant Extracts And Organic Acids, Kenneth Franklin Over Dec 2015

Microbial Safety, Shelf Life Stability, Quality Preservation, And Consumer Acceptance Of Vacuum-Infused, Irradiated Chicken Breast Meat Treated With Natural Plant Extracts And Organic Acids, Kenneth Franklin Over

Theses and Dissertations

Contamination of poultry products with food borne pathogens is a consistently recurring problem in the United States and the world. Recalls associated with chicken contamination are responsible for considerable economic losses to the poultry industry. Many decontamination steps are currently in place to reduce the likelihood of contaminated products reaching the consumer, but despite these safeguards, contamination events are still uncomfortably frequent. Irradiation is a safe and effective means of ensuring the safety of both ready-to-cook and ready-to-eat poultry but is not utilized in the United States. This is due, in part, to certain irradiation dose-dependent quality characteristic defects associated ...


Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud May 2015

Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud

Theses and Dissertations

Non-typhoidal Salmonella species have been major foodborne zoonotic pathogens causing serious problems in public health and food industry for several decades. Numerous Salmonella species have frequently been associated with different food commodities mainly poultry meat, eggs, and their products. This dissertation begins with a literature reviews discussing many aspects of Salmonella generally; and subsequently focused on two serotypes, Salmonella Enteritidis and S. Typhimurium as they are at the top of all other serovars responsible for most illness cases and outbreaks. In addition, some Salmonella strains have exhibited their ability to tolerate and survive many food processing treatments. We can divide ...


Effective Education On Consumers' Food Safety Knowledge, Perceptions, And Behaviors At Local Area Farmers' Markets, Molly Louise Albin May 2015

Effective Education On Consumers' Food Safety Knowledge, Perceptions, And Behaviors At Local Area Farmers' Markets, Molly Louise Albin

Masters Theses

Although extensive research has been conducted to understand consumers’ knowledge of food safety risks, there is a lack of research on consumers’ knowledge, perceptions, and behaviors towards risks associated with locally grown, processed, and manufactured foods sold at farmers’ markets. Recently, there has been a movement toward purchasing local foods to support local economies, out of concern for food miles, or because of a perception of higher quality goods. In Tennessee, the number of farmers’ markets has doubled in five years. Furthermore, previous research determined food safety education is most effective if developed with input from the target audience. The ...


Antimicrobial-Resistant Listeria Species From Retail Meat In Metro Detroit, Liziane Da Rocha Jan 2015

Antimicrobial-Resistant Listeria Species From Retail Meat In Metro Detroit, Liziane Da Rocha

Wayne State University Theses

A total of 138 Listeria isolates, including 58 Listeria welshimeri, 44 Listeria monocytogenes, and 36 Listeria innocua, from retail meat were characterized by antimicrobial susceptibility tests against nine antimicrobials. In addition, the 44 L. monocytogenes were analyzed by serotype identification using PCR and genotyping using pulsed-filed gel electrophoresis (PFGE). Resistance to one or two antimicrobials was observed in 32 Listeria (23.2%). No multidrug resistance was identified. Tetracycline resistance was the most common resistance phenotype and identified in 22 Listeria isolates. Low prevalence of resistance to ciprofloxacin, erythromycin, gentamicin, and vancomycin was also detected. L. innocua demonstrated the highest overall ...


Quality And Safety Attributes Of Sun-Dried Raisins From Afghanistan, Stacy A. Mccoy Oct 2014

Quality And Safety Attributes Of Sun-Dried Raisins From Afghanistan, Stacy A. Mccoy

Open Access Theses

Raisins are an important export commodity for Afghanistan, however, Afghan packers are challenged to export to markets seeking high quality products due to limited knowledge regarding their quality and safety. To evaluate this, Afghan raisin samples from pre-, semi-, and post-processed raisins were obtained from a raisin packer in Kabul, Afghanistan. The raisins were analyzed and compared to U.S. standards for processed raisins. The samples tested did not meet U.S. import standards for embedded sand, but the process used to clean the raisins is suitable to maintain food safety standards.

Previous Afghan raisin shipments have been rejected from ...


Evolution Of Food Quality Demand In The Food Service Industry In China: The Case Of Duck, Rachel Alison Carnegie Jul 2014

Evolution Of Food Quality Demand In The Food Service Industry In China: The Case Of Duck, Rachel Alison Carnegie

Open Access Theses

Booming economic growth and rising consumer incomes have impacted food preferences and purchasing behavior in China. At the same time, several internationally publicized food safety incidents, particularly in the animal husbandry sector, have heightened awareness of and concern for food safety and quality in meat and dairy. Rising quality demand and safety concerns have been studied at length in the food retail sector, but also appear to be important in the food service industry. This research uses data from a survey of duck restaurant managers and consumers in Beijing, Shanghai, Chengdu, and Guangzhou to determine preferences and willingness to pay ...


Development Of Capillary-Driven Microfludic Biosensors For Food Safety And Quality Assurance, Fei He Apr 2014

Development Of Capillary-Driven Microfludic Biosensors For Food Safety And Quality Assurance, Fei He

Doctoral Dissertations

Rapid detection technologies with high sensitivity and selectivity for pathogenic bacteria are critical in food safety and quality assurance. Traditional laboratory benchtop techniques (i.e. culture and colony counting) are time consuming and require complex sample handling. Microfluidics-based Lab-on-a-Chip (LOC) systems offer a detection alternative where all detection steps are on one portable miniaturized device. The miniaturization of rapid foodborne pathogen detection at a low cost is especially ideal for resource-limited settings or for field-use. The goal of this study was to develop a disposable miniaturized microfluidic device for on-site pathogen detection.

Capillary-driven microfluidics have been introduced in this study ...


Phenotypic, Physiological And Growth Interactions Among Salmonella Serovars, Juliany Rivera Calo Dec 2013

Phenotypic, Physiological And Growth Interactions Among Salmonella Serovars, Juliany Rivera Calo

Theses and Dissertations

This thesis consists of four research parts: a literature review that covers Salmonella spp., one of the more prominent foodborne pathogens that represents a major risk to humans (chapter 1). Understanding the growth of Salmonella serovars and strains is an important basis for more in depth research. In this case we studied a) the aerobic and anaerobic growth responses of multiple strains from six different serovars, b) how the spent media from different serovars, more importantly S. Heidelberg, affect the growth of S. Typhimurium, and c) determined whether or not two different serovars undergo competitive interactions when they were grown ...


Development Of A Predictive Modeling System For Validation Of The Cumulative Mirobial Inactivation Of The Salmonellae In Pepperoni Utilizing A Non-Pathogenic Surrogate Microorganism (Enterococcus Faecalis), Scott Donald Stillwell May 2013

Development Of A Predictive Modeling System For Validation Of The Cumulative Mirobial Inactivation Of The Salmonellae In Pepperoni Utilizing A Non-Pathogenic Surrogate Microorganism (Enterococcus Faecalis), Scott Donald Stillwell

Theses and Dissertations

Salmonellosis is the most frequently occurring bacterial foodborne illness in the United States and the human case rate has not improved for the past two decades. The federal agency responsible for oversight of meat and poultry processors has announced the intent to extend existing pathogen reduction performance standards for Salmonella spp. to cover all classes of products including fermented sausages that are currently produced under HACCP plans that are validated for control of Escherichia coli O157:H7. The proposed regulatory modifications will require processors to revalidate HACCP plan controls to achieve either a 6.5 or a 7.0 log10 ...


Sanitation Assessment Of Food Contact Surfaces And Lethality Of Moist Heat And A Disinfectant Against Listeria Strains Inoculated On Deli Slicer Components, Sabelo Muzikayise Masuku May 2012

Sanitation Assessment Of Food Contact Surfaces And Lethality Of Moist Heat And A Disinfectant Against Listeria Strains Inoculated On Deli Slicer Components, Sabelo Muzikayise Masuku

Theses and Dissertations

The overall objectives of this study were to: evaluate the efficacy of different cleaning cloth types and cloth-disinfectant combinations in reducing food contact surface contamination to acceptable levels; determine the optimum moist heat and moist heat + sanitizer treatments that can significantly reduce the number of Listeria strains on deli slicer components; and investigate if the moist heat treatment used in this study induced the viable-but-non-culturable (VBNC) state in Listeria cells. The efficacy of wiping cloths was measured using ATP-bioluminescence and total plate count methods using four different wiping cloths and silver dihydrogen citrate sanitizer on food contact surfaces. The lethality ...


The Effect Of Chlorine And Ozone In Controlling Microbes On Organically Grown Cilantro And Carrots, Adam Holtz May 2012

The Effect Of Chlorine And Ozone In Controlling Microbes On Organically Grown Cilantro And Carrots, Adam Holtz

BioResource and Agricultural Engineering

This senior project investigates the relative efficacy of ozonated water and chlorinated water for the purpose of sanitizing freshly-harvested organic produce. The aim of this study was to assist the Cal Poly Organic Farm in deciding whether or not to invest in an ozone generator. The crops used for testing were grown organically in the same field. Carrots and cilantro were harvested and promptly treated with 5 ppm ozone solution or 25 ppm sodium hypochlorite solution. Carrots were sampled at 0, 7, and 14 days storage to determine microbial populations. Cilantro was similarly tested at 0, 6, and 12 days ...


Feed Supplementation With Natural Extracts Of Cranberry And Its Efficacy On Campylobacter Colonization In Poultry, Ann Woo-Ming May 2012

Feed Supplementation With Natural Extracts Of Cranberry And Its Efficacy On Campylobacter Colonization In Poultry, Ann Woo-Ming

Theses and Dissertations

Campylobacter spp. has been identified as one of the leading causative agents of food borne diarrheal illness. Epidemiological evidence has shown that poultry is the main source for human infection. Poultry are asymptomatic carriers of Campylobacter within their gastrointestinal tract, with colonization levels reaching 106-108 cfu/g cecal content. Surveys of domestic poultry flocks have estimated that approximately 90% of flocks are positive for Campylobacter colonization. Risk assessment studies have determined that by reducing levels of Campylobacter colonization during rearing, incidences of human infection will be significantly reduced. Currently there are no consistently effective treatments to eliminate Campylobacter from poultry ...


An Analysis Of Restaurant Food Safety Violations: Human Factors, Non-Human Factors, And Food-Borne Illness, Jai Choung Apr 2010

An Analysis Of Restaurant Food Safety Violations: Human Factors, Non-Human Factors, And Food-Borne Illness, Jai Choung

UNLV Theses, Dissertations, Professional Papers, and Capstones

An estimated 76 million food-borne illnesses occur in the United States each year, causing 325,000 hospitalizations and 5,000 deaths, according to the U.S. Food and Drug Administration. Food safety is an increasingly important topic to governmental food regulators, not only in trying to reduce the number of illnesses from contaminated food. Governmental regulators also are becoming aware of the vulnerability of the food supply chain as a target for bioterrorism. Recommendations have been developed to protect the U. S. food supply from terrorism, but little of the research and recommendations relate to the food-service level.

Eighty percent ...