Food Microbiology Commons^™

Producing Bacterial Cellulose From Coffee (Coffea Arabica) Kombucha Fermentation And Assessment Of Its Efficacy To Remove Pathogenic Bacteria From Contaminated Water And A Pollutant Dye From Aqueous Solution, Federico Bueno

LSU Doctoral Dissertations

Bacterial cellulose (BC), composed of cellulosic nanofibrils, is synthesized by a symbiotic culture of bacteria and yeast during the fermentation of coffee kombucha (CK). BC may be used as a purification agent and adsorbent. The overall goal of this project was to synthesize BC from CK fermentation and assess its efficacy in removing pathogenic bacteria from contaminated water and a pollutant dye from aqueous solution. The objectives of this study were to: (1) compare BCs that were produced from different carbohydrate substrates in the fermentation of CK, (2) characterize dried BCs produced using various drying methods, (3) evaluate BC as …

Assessing The Microbiological Profile Of Raw Goat Milk And Understanding Producer Practices And Perceptions, Jacinda Skye Leopard

Theses and Dissertations

Raw milk sales are legal in 30 states, including Mississippi, where regulations are largely management-based and not food-safety related. The research objectives were to analyze the microbial profile of raw goat milk from Mississippi farms and assess food safety practices and perceptions of dairy goat farmers. Deficiencies and opportunities for improvement in raw goat milk safety were identified. Staphylococcus spp. was present in most (70%) milk samples but aligned with drying-off. E. coli, Enterobacteriaceae, and coliforms were observed in 4, 10, and 12 samples, respectively; no Salmonella spp. or Listeria monocytogenes were detected. The survey highlighted farmers' need for …

Alternative Sweeteners For Cultivating Water Kefir Grains, Morgan Barnes

Honors Theses

Water kefir is traditionally fermented using dark brown sugar due to a fast growth rate, however the use of other sweeteners, such as honey, is relatively unexplored. This paper describes the investigation of using alternative mediums made with honey, agave nectar, Truvia/stevia, and monk fruit sweetener, each supplemented with dark brown sugar on the biomass growth of water kefir grains (WKGs). Growth in these alternative mediums was compared to WKG growth in the standard medium prepared using only dark brown sugar. Two trials were conducted, each with three replicates for each experimental medium as well as three replicates of dark …

Fate Of Listeria Monocytogenes On Two Salad Blends At Ideal And Abusive Temperatures, Taran Virdi

Master's Theses

The consumption of ready-to-eat (RTE) foods has increased with popular RTE salad blends including non-traditional ingredients such as shredded Brussels sprouts, kale, red and green cabbage, chicory, and broccoli stalk. Concurrently, there has been an increase in the number of foodborne illnesses and outbreaks associated with leafy greens. The potential risk associated with these ingredients must be addressed as they have not typically been consumed raw, especially since L. monocytogenes continues to be a leading cause of foodborne illnesses and outbreaks. This study evaluated the survival of L. monocytogenes on two RTE salad blends at refrigeration, mildly abusive, and abusive …

Broiler Efficiency As Affected By Dietary Protein Supply And Grain Source, Victoria Reid

Animal Science Undergraduate Honors Theses

This experiment was conducted to compare the effects of different diet compositions on performance and carcass yield of male broilers from 15 to 36 days of age. In total, 593 male birds were divided across a randomized design that consisted of 6 dietary treatments, each with 8 replications. The treatments included pelleted diets that varied in grain type and crude protein (CP) value: 3 sorghum-based diets at 20%, 18.75%, and 17.5% CP and 3 corn-sorghum blended diets at the same CP levels. CP amounts impacted only body weight gain and feed conversion rate while feed intake only differed with grain …

Identification Of Critical Points For Bacterial Contamination In The Microbrewery Environment, Alex Ryan Thompson

All Theses

There are 8,884 craft breweries producing over 23 million barrels of beer in the United States as of 2020. These 23 million barrels of craft beer account for 12.3% of the United States beer consumption in 2020. The American craft beer industry is substantial and needs to protect its product from bacterial contamination.

Overall, beer is a microbially stable product. Beers pH, ethanol levels, CO₂ concentrations, the presence of hop-derived antimicrobial compounds, and low levels of O₂ make beer a highly unfavorable environment for most bacterial species. Furthermore, the brewing process, which involves heat treatments and chemical sanitizers …

To The Window, To The Wall: Improving Environmental Monitoring Protocols, Sarah Jones

Graduate Theses and Dissertations

Detecting microorganisms on environmental surfaces via an environmental monitoring (EM) program is part of a preventive food safety culture. Environmental monitoring should 1) verify that food safety plans are reducing cross-contamination risk from surfaces to food, 2) pinpoint microbial niches, and 3) prevent the transmission of pathogens. Environmental monitoring programs utilize EM tools, such as sponges, to sample food contact and non-food contact surfaces. However, EM tool selection is determined by the individual food firm. This dissertation evaluated and characterized factors influencing EM program effectiveness in the food industry. Specifically, this dissertation focuses on the release of microorganisms from EM …

Evaluation Of Human Microbiota-Associated (Hma) Porcine Models To Study The Human Gastrointestinal Microbiome, Nirosh D. Aluthge

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Research conducted in the past couple of decades has showcased the importance of the gut microbiota in human health and well-being. While many studies have reported on the differences in community membership between a disease state and a healthy state, few have investigated the mechanisms through which an aberrant microbiota contributes to a disease phenotype. One of the primary reasons for this are the many technical and ethical barriers to conducting the necessary studies directly in human individuals. Human microbiota-associated (HMA) porcine models have the potential to become important research tools which can enable the testing of hypotheses regarding host-microbiota …

Effects Of Thermal Processing On Peach Puree Of Different Cultivars: Analysis Of Biochemical Alteration, Non-Enzymatic Browning Reaction, And Color Changes, James Hayes

All Theses

The effects of pasteurization temperature and time on the change in seven peach puree variables over a 6-week accelerated shelf-life test (35°C) were evaluated. The variables of interest were three color measures [ L* (lightness), a* (redness), and b* (yellowness)]; two brown pigment measures [spectrophotometric absorption at 420 nm (Browning Index) and 443 nm (Hydroxymethylfurfural)]; °Brix; and pH). Puree was collected from three different cultivars (2 freestone and 1 clingstone) and puree samples from each cultivar were subjected to 20 combinations of pasteurization temperatures (70°C, 80°C, 90 °C, 100°C) and same hold times (0 minutes, 1 minute, 3 minutes, 5 …

Preparation Of Proteins And Peptides From Heat-Stabilized Defatted Rice Bran Via Solid State Fermentation And Investigating For Skin Health, Ali A. Bisly

Graduate Theses and Dissertations

Heat-stabilized defatted rice bran (HDRB) is an abundant and inexpensive agro-industrial by-product of rice milling and rice oil extraction process. Furthermore, HDRB is a potential source of proteins. However, the direct protein extraction has low yield of protein due to the impact of heat stabilization and oil extraction process which made the HDRB proteins bound and interact with other components. This research is based on using solid-state fermentation (SSF), which is a natural and cost-effective approach to facilitate protein extraction from HDRB using Bacillus subtilis (natto) Takahashi as a microorganism.

Response surface methodology (RSM) analysis was used with Box-Behnken design …

Evaluating The Microbial Quality And Use Of Antimicrobials In Raw Pet Foods, Leslie Pearl Cancio

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Raw meat-based diets (RMBDs) are emerging pet foods that pose food safety risks because of the potential presence of pathogens that could cause illness to humans. In this research, the microbial quality of select RMBD products sold by pet food companies online and the use of chemical antimicrobials to reduce the microbial load in chicken liver, a common RMBD ingredient, were evaluated.

Ground meat blends and livers from four animal species (beef, pork, chicken, turkey) were purchased from four online companies that delivers directly to consumers through parcel businesses. Products were procured at three different times during one year and …

Knowledge-Informed Data-Driven Modeling Of Microbial Inactivation In Food, Steve Zhang, Firnaaz Ahamed, Hyun-Seob Song

UNL Student Research Days Posters, Graduate

Prevention of the growth of harmful microorganisms in food products is an important requirement for ensuring food safety and quality. Mathematical models to predict the quantitative changes in microbial populations in food to the variations of environmental conditions are useful tools in this regard. Current approaches that use empirical formulation generate arbitrary forms of model equations, impeding systematic analysis towards identifying key factors governing microbial growth and inactivation in food. To address this challenge, we present a data-driven modeling pipeline that enables automatic discovery of model equations (through parsimonious selection of relevant terms in a pre-built library) without having to …

A Review On Empirical Approach To Therapeutic Recombinant Protein Production Factories: Applications, Pharmacokinetics And Challenges, Zahra Naz, Ambreen Kanwal, Asima Tayyeb

Journal of Bioresource Management

Major portion of the proteins in a cell refers to their critical roles in metabolism of the living body. Proteins dysfunction results in the severe disorders which need to be treated in time. For this, respective proteins can be extracted by the external sources and be supplied to the human beings. Such medicinal proteins are known as therapeutic proteins (TPs). This review summarizes some of the key areas about these miracle proteins like their types, classification, production factories, routes of administration, pharmacokinetics, and potential applications. Furthermore, challenges and hurdles faced in getting a potential protein drug, its FDA approval and …

Lytic Bacteriophages And Lactic Acid As Processing Aids Against Salmonella Spp. And Escherichia Coli O157:H7 On Marinated And Tenderized Pork Loins, Sherita Li

Master's Theses

Within the last decade, pork consumption has steadily increased and continues to be the most consumed meat globally. However, pathogenic bacterial strains resistant to antibiotics have also been increasingly found in pig farms, animals, and the environment. Bacterial food poisoning cases due to Salmonella spp. and Escherichia coli (E. coli) O157:H7 appear to be linked with a variety of pork products. The meat industry has recognized that research is needed to combat the multi-drug resistance in foodborne pathogens with alternative methods of control. This study evaluated the effects of both E. coli- and Salmonella-specific lytic bacteriophages and …

Development Of Add-On Materials To Supplement Food Safety Modernization Act Trainings In The Western U.S., Jovana Kovacevic

Journal of Extension

During the 2017 annual meeting of the Western Regional Center to Enhance Food Safety, 52 representatives from 15 western states/territories, regional centers funded through USDA-NIFA Food Safety Outreach Program, federal and state government agencies, and non-governmental organizations prioritized topics for the Food Safety Modernization Act (FSMA) training materials that address region-specific agricultural production and processing systems. This article describes supplemental materials or “add-ons” developed to support FSMA-related food safety trainings. Although the materials were developed for the western region stakeholders, they can be applied or adapted to other regions in or outside the U.S. to enhance food safety trainings.

Cultural Sensitivity: A Requirement When Developing Food Safety Interventions, Lillian Nabwiire, Angela M. Shaw, Gail R. Nonnecke, David D. Minner, Ellen Johnsen, Louis E. Petersen Jr

Journal of Extension

Extension materials that are sensitive to changing demographics and culture increase relevance and compliance with food safety practices. Produce safety extension materials were developed for U.S. Virgin Islands (USVI) produce growers to help with compliance with a new food safety rule. We developed employee training materials based on a needs assessment and behavioral change was evaluated six months after dissemination. The original materials were not seen as culturally appropriate but after modifications, improvements in food safety practices and behavior changes were observed. These results suggest that extension educators should seek feedback from target populations about potential interventions before implementation.

Bovine Respiratory Microbiota Of Feedlot Cattle And Its Association With Disease, Jianmin Chai, Sarah F. Capik, Beth Kegley, John T. Richeson, Jeremy G. Powell, Jiangchao Zhao

Animal Science Faculty Publications and Presentations

Bovine respiratory disease (BRD), as one of the most common and costly diseases in the beef cattle industry, has significant adverse impacts on global food security and the economic stability of the industry. The bovine respiratory microbiome is strongly associated with health and disease and may provide insights for alternative therapy when treating BRD. The niche-specific microbiome communities that colonize the inter-surface of the upper and the lower respiratory tract consist of a dynamic and complex ecological system. The correlation between the disequilibrium in the respiratory ecosystem and BRD has become a hot research topic. Hence, we summarize the pathogenesis …

Modeling The Flow And Creep Compliance Properties Of Ice-Cream Mixes, Hiran Ranaweera

Electronic Theses and Dissertations

This work documented the influence of the protein source (MPC80 and WPC80), protein content (4-12%), and temperature (5-35ºC) on the rheological behavior (flow curve, frequency sweep, and creep-recovery) of ice-cream mixes (ICM). For each protein source, the viscosity of the ICM was satisfactorily modeled (𝑅2>0.98, 𝑅2 𝑎𝑑𝑗>0.98, and E0.99), while the recovery phase was represented by an empirical model. The percentage of recovery (%R) of the ICM significantly decreased with the protein content.

Impact Of Natural Cheese Composition On Proteolysis And Its Effects On Process Cheese Functionality, Natasha Scherber

Electronic Theses and Dissertations

Cheddar cheese is a commodity and a top-selling cheese in the United States. Enhanced flavors of cheddar cheese requires aging, which will allow proteolysis increase. Proteolysis is the most complex process that happens in cheese manufacturing and can be difficult to control because of environmental factors and compositional characteristics. The ripening process, which is the most timely and costly procedure in cheese manufacturing, can also be unpredictable when aspects, such as cheese composition, are changed. The coagulant is responsible for the first stage in proteolysis, which will produce large peptides. Small peptides are subsequentially produced during the second stage by …

Practices Of Vitamin D Supplementation Leading To Vitamin D Toxicity: Experience From A Low-Middle Income Country, Siraj Muneer, Imran Siddiqui, Hafsa Majid, Nawazish Zehra, Lena Jafri, Aysha Habib

Department of Pathology and Laboratory Medicine

Introduction: The trend of prescribing VD preparations for nonspecific body aches and self-medication has increased significantly. The importance of vitamin D toxicity (VDT) has been underestimated and under recognized. This study was done to determine the frequency toxicity (>150 ng/ml) in subjects for 25-hydroxyvitamin D (25OHD) and evaluate the vitamin D (VD) supplements used by these subjects.
Methodology: This descriptive cross-sectional study was conducted at the Section of Chemical Pathology, Aga Khan University Hospital Karachi from April 2020 to March 2021. Subjects with 25OHD toxicity were contacted and information related to history of calcium and VD supplementation were collected. …

Investigation Of A Novel Throughput Agent On Production Rate And Pellet Quality And The Development Of A Lab-Based Method To Predict Salmonella Reduction In Poultry Feed, Utilizing Varying Feed Manufacture Parameters, Timothy Paul Boltz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Two experiments were conducted to evaluate a novel throughput agent and its mechanisms on production rate and pellet quality. An additional experiment using lab-based methods and models was conducted to predict Salmonella reduction in mash broiler feed. Feed mill pellet production rate is of great importance to integrated meat bird production. Feed hygienics are also of increasing concern for poultry producers.

In chapter 2, the effect of AZOMITE® (AZM) and varying inorganic phosphate sources (IPS) on pellet mill production rate and pellet quality was assessed. It is documented that the naturally abrasive properties of inorganic phosphate sources may scour the …

Comparison Of Antimicrobials And Delivery Methods On The Inactivation Of Listeria Monocytogenes On Apples, Rebecca B. Stearns

Graduate Theses, Dissertations, and Problem Reports (ETD)

Introduction: Due to multi-state outbreaks of listeriosis on apples in 2015, 2017, and 2019, Listeria Monocytogenes (L. monocytogenes) has been deemed an emerging, under researched pathogen by the USDA-NIFA. Therefore, this study evaluated the efficacy of SaniDate 5.0®’s (SD) ability to inactivate L. Monocytogenes on apples when delivered through electrostatic sprayer (ES), garden sprayer (GS), and dip methods.

Methods: Organic apples were dip-inoculated with L. monocytogenes for 5 min and then dried for 10 min. Once dried, the inoculated apples were untreated (control), sprayed with water only, or treated with SD, 0.0064, 0.1, 0.25 and 0.50% for 20 …

Evaluation Of The Kitchen Microbiome And Food Safety Behaviors Of Predominantly Low-Income Families, Christina K Carstens, Joelle K Salazar, Shreela V Sharma, Wenyaw Chan, Charles Darkoh

Faculty, Staff and Student Publications

Bacterial pathogens in the domestic environment present a risk to residents, particularly among susceptible populations. However, the impact of consumer demographic characteristics and food handling methods on kitchen microbiomes is not fully understood. The domestic kitchen bacterial communities of ten predominantly low-income families in Houston, TX, were assessed in conjunction with a cross-sectional food safety survey to evaluate differences in household and surface-specific microbiomes and bacterial foodborne pathogen presence. Three kitchen surfaces within each household, including the sink drain, the refrigerator handle, and the counter, were environmentally sampled and metataxonomically evaluated via targeted 16S rRNA sequencing. Disposable dish sponges were …

Evaluate The Efficacy Of A Mixture Of Peroxyacetic Acid And H2o2 Against The Survival And Cross-Contamination Of The Salmonella Surrogate Enterococcus Faecium On Tomatoes During Triple-Wash, Corey Waitman Coe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Triple-wash with a mixture of peroxyacetic acid and H2O2 (SaniDate-5.0) during post-harvest processing of fresh produce has been recommended by West Virginia Small Farm Center to improve microbial safety. It has been well recognized that the washing of produce is more important for preventing cross-contamination than reducing foodborne pathogens. Furthermore, it may help improve public confidence in that the produce they obtain from locally grown farmers is safe for their consumption. determine the efficacy of SaniDate-5.0 for reducing the survival and preventing cross-contamination of the Salmonella surrogate Enterococcus faecium on tomatoes during triple-wash.

E. faecium ATCC-8459 (resistant to 100-ppm nalidixic-acid) …