Combinations Of Multiple Natural Antimicrobials With Different Mechanisms As An Approach To Control Listeria Monocytogenes, 2016 University of Tennessee, Knoxville
Combinations Of Multiple Natural Antimicrobials With Different Mechanisms As An Approach To Control Listeria Monocytogenes, Savannah Grace Hawkins
To improve food safety and shelflife requires the use of preservation processes, such as physical (heat, refrigeration) or chemical (antimicrobial addition) processes. Regulatory approved synthetic food antimicrobials (preservatives) have some uses but are very limited in their spectrum of activity. Thus, alternatives are needed to conventional chemical antimicrobials. One method is to use naturally occurring antimicrobials, especially those found in spices and herbs, essential oils (EO) and essential oil components (EOC). EOs have been shown to have antimicrobial activity but the activity is highly variable. Finding a combination of EOs, EOCs, or other natural antimicrobials that act synergistically would allow ...
Identification Of Potential Bacterial Surrogates For Validation Of Thermal Inactivation Processes Of Hepatitis A Virus, 2016 University of Tennessee, Knoxville
Identification Of Potential Bacterial Surrogates For Validation Of Thermal Inactivation Processes Of Hepatitis A Virus, Marcel Schmidt
Thermal treatment is a method for inactivating pathogens in a wide range of food products. Recent studies have shown that hepatitis A virus (HAV) has a D72°C [D72 degree celcius] of 0.9 min in buffer which is greater than vegetative bacterial pathogens. Common surrogates, such as Listeria innocua, are not resistant enough to be used as surrogates for HAV, thus, new surrogates need to be identified. The purpose of this study was to compare the thermal inactivation kinetics (D- and z-values) of Staphylococcus carnosus in different foods and different incubation temperatures to identify a potential surrogate for ...
Assessing Stress Responses To Atmospheric Cold Plasma Exposure Using Escherichia Coli Knock Out Mutants, 2016 Dublin Institute of Technology
Assessing Stress Responses To Atmospheric Cold Plasma Exposure Using Escherichia Coli Knock Out Mutants, Lu Han, Daniela Boehm, Sonal Patil, Patrick Cullen, Paula Bourke
Aim: This study investigated the effect of Atmospheric cold plasma (ACP) exposure induced stress on microbial inactivation patterns and the regulation of genes involved in the microbial stress response in conjunction with key processing parameters of exposure time and post treatment storage time.
Methods and Results: Cell suspensions of Escherichia coli BW 25113 and its isogenic knock-out mutants in rpoS, soxR, soxS, oxyR and dnaK genes were treated with high voltage ACP in a sealed package for 1, 3 and 5 min followed by 0, 1 and 24 h post-treatment storage. ROS densities and colony formation were determined. ΔrpoS strain ...
From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, 2016 University of Nebraska-Lincoln
From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza
Dissertations & Theses in Food Science and Technology
This project aimed to implement the use of metal silos to improve quality and safety of maize consumed by inhabitants of the highlands of Guatemala. This manuscript includes a literature review of the maize production chain in Guatemala, a survey about agricultural practices used in the region of study, as well as a characterization of the analyzed maize regarding its mycoflora, nutritional composition, and insect infestation. To better understand the current situation regarding agricultural practices and maize consumption, a survey was carried out. Sample consisted of 280 families representing 14 rural communities distributed in the townships of Todos Santos and ...
Exploration Of Chemical And Biological Management Strategies For Diaphorina Citri The Primary Vector Of Candidatus Liberibacter Asiaticus, 2016 University of Texas at Tyler
Exploration Of Chemical And Biological Management Strategies For Diaphorina Citri The Primary Vector Of Candidatus Liberibacter Asiaticus, Gretta Marie Sharp
Diaphorina citri (Hemipteran: Psyllidae), the Asian citrus psyllid, is a phloem-feeding, invasive species endemic to southern Asia that was first identified in the United States in Florida in 1998. Since introduction, D. citri has spread across the major citrus growing regions of the United States. This is of great concern to the citrus industry because D. citri is the primary vector of Candidatus Liberibacter asiaticus the causal agent of Haunglongbing (HLB). Haunglongbing is the most economically devastating disease of citrus causing an estimated 8.92 billion dollars lost in revenue and 4.62 billion dollars lost in gross domestic product ...
A Novel And Rapid Staphylococcus Aureus Bacterial Identification Method Utilizing Immunomagnetic Beads And Single Cell Laser-Light Scattering, Kaylagh Hollen
All NMU Master's Theses
Staphylococcus aureus is the most commonly isolated human associated bacterial pathogen. It plays an important role in skin and soft-tissue infections, pneumonia, endocarditis, osteomyelitis, foreign-body infections, and sepsis. S. aureus diagnosis and treatment requires a minimum of 24-48. With this in mind, previous studies suggest that faster pathogen identification has been linked to improved patient outcomes. Improved patient outcomes including a reduction in hospitalization time, decreased risk of nosocomial infections, and decreased in medical costs. The impact of faster identification on patient outcome has led us to develop an alternative method of S. aureus identification via ImmunoMagnetic Separation (IMS) and ...
Synbiotic Ice Cream As A Probiotic Carrier Tested In A Human Blind Crossover Trial, 2016 University of Nebraska-Lincoln
Synbiotic Ice Cream As A Probiotic Carrier Tested In A Human Blind Crossover Trial, Erin M. Mcnamara
Nutrition & Health Sciences Dissertations & Theses
Diet is an important factor in gastrointestinal health. A synbiotic food option utilizing prebiotic and probiotic ingredients may be beneficial for improving gastrointestinal health. To conduct a human subject study of synbiotic ice cream containing prebiotic (inulin) and two strains of probiotics (Lactobacillus casei KE99 and Bifidobacterium bifidum) to determine its effectiveness as a carrier for a these ingredients and to identify any negative gastrointestinal side effects.
The study started with baseline data collection including a food frequency, a three day food recall, and one stool sample. The study was a 12 week crossover design with three weeks consuming placebo ...
Studies Of Debaryomyces Hansenii Killer Toxin And Its Effect On Pathogenic Bloodstream Candida Isolates, 2016 University of Nebraska-Lincoln
Studies Of Debaryomyces Hansenii Killer Toxin And Its Effect On Pathogenic Bloodstream Candida Isolates, Rhaisa A. Crespo Ramírez
Dissertations & Theses in Food Science and Technology
Candida species are normal commensal organisms found in the skin, mouth, and gastrointestinal and genitourinary tracts of humans. Candida albicans is a normal component of the gut flora, and the oral and genital cavities. However, this organism is an opportunistic pathogen and it is one of the most frequently isolated species from patients with nosocomial fungal infections. Candida infections have grown in recent years due to antimycotics resistance and the extensive use of antibiotics. This has pushed scientists to look for alternative therapeutic agents to treat fungal infections.
Yeasts can produce toxic proteins called “mycocins” or “killer toxins” that can ...
The Effect Of Salt Reduction On The Microbial Composition And Quality Characteristics Of Sliced Roast Beef And Turkey, 2016 University of Nebraska - Lincoln
The Effect Of Salt Reduction On The Microbial Composition And Quality Characteristics Of Sliced Roast Beef And Turkey, Chad G. Bower
Theses and Dissertations in Animal Science
This study analyzed the effects of salt reduction on microbiological composition and quality characteristics of deli-style turkey breast and roast beef. Turkey breast and roast beef were manufactured with four different salt concentrations: 1.0%, 1.5%, 2.0%, and 2.5% on a meat block basis in addition to sugar, phosphate, and water. Samples were cooked, chilled overnight, sliced, and packaged. On the day of slicing, samples were evaluated for water activity, cooking yield, proximate composition and percent salt. Samples were evaluated throughout 18w of refrigerated storage for pH, texture profile analysis, aerobic plate count (APC), and anaerobic plate ...
Antibacterial Effects Of Peppermint, Mentha Piperita Essential Oil In Free-Form And In Nanoparticles On Pseudomonas Fluorescens, 2016 University of Nebraska-Lincoln
Antibacterial Effects Of Peppermint, Mentha Piperita Essential Oil In Free-Form And In Nanoparticles On Pseudomonas Fluorescens, Car Reen Kok, Junsi Yang, Ozan Ciftci, Robert Hutkins
UCARE Research Products
Mentha piperita, commonly known as peppermint originally came from Europe and the Middle East and its oil is commonly used in traditional medicine and aromatherapy. Like many other free essential oils (EO), peppermint oil is believed to possess antimicrobial properties.
However, the application of EO in food as an antimicrobial agent has yet to be established. This would require proper formulation of the EO for it to be viable in foods. This study aims to test the effects of both free Mentha piperita EO and Mentha piperita EO nanoparticles against Pseudomonas fluorescens and compare their inhibitory effects. We used nanoparticles ...
An Analysis Of Bacterial Contamination Of Chicken Eggs And Antimicrobial Resistance, 2016 College of Saint Benedict/Saint John's University
An Analysis Of Bacterial Contamination Of Chicken Eggs And Antimicrobial Resistance, Holly Spitzer
All College Thesis Program
Chicken eggs are a major component of American diets, with an average yearly consumption of approximately 250 eggs per person (American Humane Society). While highly nutritious, eggs are also one of the leading causes of food poisoning and food borne illness in the United States. Eggs may become contaminated by a number of different types of bacteria during production, including Salmonella, a group of bacteria that, according to the CDC, causes more than 1.2 million cases of food borne illness in the United States every year. In an effort to decrease the frequency of bacterial contamination, many food producers ...
Effect Of Reduced Sodium Cheese On The Growth Of Pathogenic Bacteria And Inactivation Of Listeria Innocua Using Supercritical Fluid Extraction With Co2, 2016 California Polytechnic State University - San Luis Obispo
Effect Of Reduced Sodium Cheese On The Growth Of Pathogenic Bacteria And Inactivation Of Listeria Innocua Using Supercritical Fluid Extraction With Co2, Suyapa Padilla Antunez
Master's Theses and Project Reports
Listeria monocytogenes continues to challenge the dairy industry in causing post-process contamination of cheeses. To reduce risk of contamination, it is crucial to understand the growth and survival of pathogenic bacteria in cheese products and to develop post-process mitigation strategies. This study evaluated the fate of pathogens in reduced and regular sodium Mozzarella cheese, and the potential of Supercritical Fluid Extraction with CO2 (SFE) to reduce Listeria innocua on Mozzarella and Queso Fresco. The survival of L. monocytogenes, Salmonella, and E.coli O157:H7 (2-3 log CFU/g) in reduced sodium Mozzarella (1.62%), compared to regular sodium Mozzarella ...
Identification Of Soil Microbes Capable Of Utilizing Cellobiosan, 2016 Iowa State University
Identification Of Soil Microbes Capable Of Utilizing Cellobiosan, Jieni Lian, Jinlyung Choi, Yee Shiean Tan, Adina C. Howe, Zhiyou Wen, Laura R. Jarboe
Chemical and Biological Engineering Publications
Approximately 100 million tons of anhydrosugars, such as levoglucosan and cellobiosan, are produced through biomass burning every year. These sugars are also produced through fast pyrolysis, the controlled thermal depolymerization of biomass. While the microbial pathways associated with levoglucosan utilization have been characterized, there is little known about cellobiosan utilization. Here we describe the isolation and characterization of six cellobiosan-utilizing microbes from soil samples. Each of these organisms is capable of using both cellobiosan and levoglucosan as sole carbon source, though both minimal and rich media cellobiosan supported significantly higher biomass production than levoglucosan. Ribosomal sequencing was used to identify ...
Acoustic Emission Of Lactococcus Lactis Ssp. Lactis C2 Infected With Three Bacteriophages C2, Sk1 And Ml3, 2016 University of Kentucky
Acoustic Emission Of Lactococcus Lactis Ssp. Lactis C2 Infected With Three Bacteriophages C2, Sk1 And Ml3, Luxi Meng
Theses and Dissertations--Animal and Food Sciences
The objective of this research was to monitor the Acoustic Emission (AE) produced by Lactococcus lactis ssp. lactis C2 infected with three bacteriophages (c2, sk1 and ml3 at 90 min) using an acoustic emission-monitoring device which was designed at University of Kentucky in Lexington KY. The acoustic emission data was collected and then analyzed. These Acoustic Emission (AE) data suggested that bacteriophage ml3, sk1 and c2 can easily be distinguished by the differences in Absolute Energy (ABE), Centroid Frequency (CF) and Peak Frequency (PF) signals. The AE data suggested that bacteriophage sk1 and c2 caused greater stress on the lactis ...
Proteomics Study Of Pre-Harvest Sprouting In Wheat, 2016 South Dakota State University
Proteomics Study Of Pre-Harvest Sprouting In Wheat, Pramod Khadka
Theses and Dissertations
Pre-harvest sprouting (PHS) of wheat (Triticum aestivum L.) is a condition characterized by the early germination of spikes during moist environmental conditions. PHS lowers yield, degrades the quality of grain and thus limits the profits of wheat producers groups. During this investigation, proteomics studies of PHS-resistant and PHS-susceptible wheat embryos were conducted at different imbibition time periods via a cutting-edge technology called iTRAQ. Proteomic analysis revealed that 190 differentially expressed proteins might be involved in various cellular functions, such as carbohydrate metabolism, nitrogen metabolism, stress response, redox regulation, ATP synthesis, and protein translation, during this untimely germination of the wheat ...
Controlling Microbial Safety Challenges Of Meat Using High Voltage Atmospheric Cold Plasma, 2016 Dublin Institute of Technology
Controlling Microbial Safety Challenges Of Meat Using High Voltage Atmospheric Cold Plasma, Lu Han, Dana Ziuzina, Caitlin Marie Heslin, Daniela Boehm, Apurva Patange, David Millan-Sango, Vasilis Valdramidis, Patrick Cullen, Paula Bourke
Atmospheric cold plasma (ACP) is a non-thermal technology, effective against a wide range of pathogenic microorganisms. Inactivation efficacy results from plasma generated reactive species. These may interact with any organic components in a test matrix including the target microorganism, thus food components may exert a protective effect against the antimicrobial mode of action. The effect of an in-package high voltage ACP process applied in conjunction with common meat processing MAP gas compositions as well as bacteria type and meat model media composition have been investigated to determine the applicability of this technology for decontamination of safety challenges associated with meat ...
Influence Of Inoculum Preparation Upon Sensitivity Of Common Food Borne Pathogens To Emulsion Based Antimicrobials, 2016 University of Massachusetts - Amherst
Influence Of Inoculum Preparation Upon Sensitivity Of Common Food Borne Pathogens To Emulsion Based Antimicrobials, Dillon Sd Murray
Masters Theses May 2014 - current
Antimicrobial optimization procedures use the most resistant bacterial culture that could be present in the food to determine the levels of treatment needed to ensure safety. These procedures usually only focus on one method of preparing these inoculums for testing despite prior research showing that the preparation of the culture can influence how the culture reacts to a treatment. In this work, planktonic cells grown in a liquid media and sessile cells grown on a similar solid media were subjected to identical emulsion based antimicrobial systems. The cultures were monitored over time and their numbers periodically enumerated. Weibullian destruction models ...
Novel Advancements For Improving Sprout Safety, 2016 University of Massachusetts Amherst
Novel Advancements For Improving Sprout Safety, Kyle S. Landry
Doctoral Dissertations May 2014 - current
All varieties of bean sprouts (mung bean, alfalfa, broccoli, and radish) are classified as a “super-food” and are common staples for health conscious consumers. Along with the proposed health benefits, there is also an inherent risk of foodborne illness. When sprouts are cooked, there is little risk of illness. The purpose of this dissertation was to explore novel techniques to minimize or prevent the incidence of foodborne illness associated with the consumption of sprouts. Three areas were investigated: 1) the use of a biocontrol organism, 2) the use of a novel spontaneous carvacrol nanoemulsion, and 3) the influence of the ...
Comparative Study Of The D-Values Of Salmonella Spp. And Enterococcus Faecium In Wheat Flour, 2015 University of Nebraska-Lincoln
Comparative Study Of The D-Values Of Salmonella Spp. And Enterococcus Faecium In Wheat Flour, Didier Dodier
Dissertations & Theses in Food Science and Technology
Low-moisture foods contaminated with Salmonella spp. have been implicated in several foodborne illness outbreaks in the United States. The food industry has to incorporate preventive control in their process and validate thermal processes to assure food safety. The thermal destruction of Enterococcus faecium ATTC 8459 and Salmonella spp. was determined at 3 water activity levels (0.11, 0.18 and 0.33) at 80ºC, 85ºC and 90ºC. Aerobic plates counts petrifilms were used as non-selective medium for both bacteria, Enterobacteriaceae petrifilms were used as selective medium for Salmonella spp., and peptone water modified with sodium azide as a selective medium ...
Inactivation Of Escherichia Coli O157:H7 And Shiga Toxin Producing E. Coli (Stec) Throughout Beef Summer Sausage Production And The Use Of High Pressure Processing As An Alternative Intervention To Thermal Processing, 2015 University of Nebraska-Lincoln
Inactivation Of Escherichia Coli O157:H7 And Shiga Toxin Producing E. Coli (Stec) Throughout Beef Summer Sausage Production And The Use Of High Pressure Processing As An Alternative Intervention To Thermal Processing, Eric L. Oliver
Dissertations & Theses in Food Science and Technology
Escherichia coli O157:H7 and six additional serogroups of Shiga Toxin-producing E. coli (STEC-7) have been implicated in foodborne illness outbreaks related to fermented sausage products and are considered adulterants by the USDA-FSIS. The objective of this study was to evaluate high pressure processing (HPP) as an alternative to thermal treatment to reduce STEC-7 meeting the USDA-FSIS performance standards (5.0-log reduction). A rifampicin-resistant, non-pathogenic E. coli (surrogate) cocktail, was used in manufacturing testing. Sausages were fermented at ~42.2°C, slowly increased to 54.4°C internal temperature, cold showered, and chilled for 6 hours. Sampling occurred post-fermentation (PF ...