Digital Commons Network^™

Multiphysics Modeling To Understand Microwave-Food Interactions In A Multi-Port Solid-State Microwave System., Kartik Verma

Masters Theses

Multiphysics modeling plays a crucial role in understanding the complexities of microwave-food interactions, especially in multi-port solid-state microwave systems where microwave parameters can be precisely and dynamically controlled. However, previous models using simplistic or manually measured oven geometries face challenges in accurately simulating the microwave heating process. This study first developed a robust 3-D scanning approach to capture precise geometric details of the oven cavity, incorporating them into multiphysics modeling for solid-state microwave heating. Furthermore, a quantitative validation approach was also developed to characterize modeling accuracy against experimental results. The results showed that multiphysics modeling with 3-D scanned geometry demonstrated …

Development Of Domestic Oleochemicals For Coating Applications, Caleb M. Metzcar

Masters Theses

The overall objective of the present work is to explore new applications of soybean oil based oleochemicals. Two main applications are developed; one using soybean oil, acrylic acid, and nonthermal plasma (NTP) treatment to dye para-aramids with cationic and non-ionic pigments, the other using fatty acids to synthesize waxes with bound quaternary ammonium compounds (QAC), an antimicrobial functional group, for fruit and vegetable postharvest coating. The color strength of the dyed fabric was quantified and the effect of the dyeing on material strength was evaluated to identify the optimal treatment condition. Antimicrobial waxes have been successfully developed that some structures …

Characterization Of Key Odorants In Cumberland Rosemary, Conradina Verticillata, Claire Mackenzie Gorman

Masters Theses

Conradina verticillata Jennison, commonly known as Cumberland Rosemary, is a threatened plant from the mint family Lamiaceae. This species is a flowering, perennial shrub found in only a few counties of Kentucky and Tennessee. Cumberland Rosemary possesses a unique aroma profile; however, the odorants responsible for its aroma have not been previously identified. In this study, a total of 32 odorants were identified in Cumberland Rosemary using gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Odorant flavor dilution (FD) factors were determined through the application of aroma extract dilution analysis (AEDA). Seven odorants with FD factors ≥ [greater than or …

Modeling And Quality Analysis Of Radio Frequency Heating Of Low Moisture Foods, Qianyi Chen

Masters Theses

Low moisture food is usually considered as high safety food. Since its low water activity (aw < 7), this would be a strict environment for pathogen microbes to grow in the low moisture food. However, the recent outbreaks of Salmonella in low moisture foods indicated the possibility of microbiological contamination happened during the harvesting, processing or transportation of food products. Since the bad heat conduction of conventional thermal process on low moisture food, radiofrequency (RF) treatment is a promising technology to improve the heating efficiency with its volumetric heating. Nevertheless, non-uniformity heating is still a challenge in RF technology. There are two research chapters in this study. The first research chapter was to use computer modeling to understand the improvement of applied immersion fluids on the RF heating of the cornflour. The model had a good agreement with the experiment results. The modeling results showed that the soybean oil immersion could reduce the electric field distortion to get the best heating uniformity. Also, the higher sample heating rate caused by soybean oil immersion was mainly because of higher electromagnetic power absorption and lower surface heat loss. The heating efficiency of RF was improved but less study focused on the quality analysis of flour. Therefore, the second research study is to evaluate the effect of RF and extensive hot air oven processing on the quality and functionality of all-purposed flour.

Efficacy Of A Mushroom Derived Saltiness Enhancer In Increasing Saltiness And Consumer Acceptance In Low Sodium Applications, Lindsay Jenkinson

Masters Theses

The average American consumes sodium at excessive levels resulting in a multitude of adverse health effects. To reduce these risks, it is imperative to lower consumption rates. When sodium is reduced in a product, the main effect is decreased saltiness and often corresponds with reduced consumer acceptance. In addition to addressing the issue of sodium reduction, attenuating effects such as reduced consumer acceptance is also of importance.

Consuming and perceiving food is a multimodal experience, involving tastes, smells, and trigeminal sensations to produce a singular percept of flavor. This is an example of multisensory integration. When stimuli through different sensory …

Aroma Chemistry Of Daldinia Childiae Fermentation, Andrew Jason Moore

Masters Theses

An investigation to identify odorants responsible for a pleasant woody perfume-like aroma produced in the fermentation broth of the fungus Daldinia childiae (J.D. Rogers & Y.M. Ju) was conducted. Thirty odorants were identified from 30-day old fermentations employing solvent-assisted flavor evaporation (SAFE) and aroma extract dilution analysis (AEDA). Eleven odorants with flavor dilution (FD) factors ≥ 16 were quantitated using stable isotope dilution assays (SIDA), and odor activity values (OAV) determined. Odorants with the highest OAVs included guai-11-en-10-ol (woody, OAV 102689), 1-octen-3-one (mushroom, OAV 9025), sotolon (maple, OAV 458), and (2E)-non-2-enal (fatty, OAV 70). An odor-simulation model formulated …

Transcriptomic Analysis Of Salmonella Enterica Newport Adaptive Response To Oxidative Antimicrobials, Dara Melanie Smith

Masters Theses

Agricultural water systems are a known potential source for contamination of fresh produce with foodborne pathogens including Listeria monocytogenes, pathogenic Escherichia coli, as well as Salmonella enterica strains. To reduce this associated risk, antimicrobials such as hypochlorite compounds and peroxyracetic acid (PAA) have been utilized as in-line irrigation disinfectants and as post-harvest treatments. These treatments are considered effective and commonly used; however, pathogenic microbes like Salmonella have the ability to adapt to many environmental conditions. Adaptive response to environmental factors like oxidative conditions, contributes to transfer, attachment, and resilience of Salmonella on surfaces. Through RNA sequencing and analysis …

Effect Of Ultrasonication On The Physicochemical Properties Of Sorghum Kafirin And Evaluation Of Its Anti-Inflammatory Properties In Vitro, Andrew Cullen Sullivan

Masters Theses

Sorghum is one of the hardiest, most drought resistent cereal grains known to exist, providing the bulk of nutritional content for many semi-arid regions and developing countries throughout Africa and southwestern Asia. It contains dense nutritional value, but due to inhibition factors within the grain, much of these nutrients are indigestible. Access to these nutrients, which have shown to contain high contents of bioactive molecules linked to the decrease of prevalence of chronic disease, must then be facilitated before consumption. In sorghum, these molecules could include complex carbohydrates, proteins and polyphenols. The overall objective of this study was to determine …

Heat Inactivation Kinetics Of Tulane Virus And Aichi Virus, Sukriti Ailavadi

Masters Theses

Human noroviruses (HNoVs) and Aichi virus (AiV) causes significant number of gastrointestinal diseases worldwide. Tulane virus (TV), a cultivable HNoV surrogate, is used to determine control measures against HNoV. The objectives of this study were to determine the heat inactivation kinetics of TV and AiV in cell-culture media and TV in spinach using the first-order and Weibull models. TV and AiV in cell-culture media at ~7 log PFU/ml in 2-ml glass vials were heated at 50-58°C [degree Celsius] up to 10 min in a circulating water-bath. Surviving infectious viruses were enumerated by standard plaque assays using confluent host cells in …

Comparative Chemical Characterization Of Lunasin-Enriched Preparations And Modifications Of The Inflammasomes In Vitro, Samuel James Price

Masters Theses

Soybean (Glycine max) is one of the most cultivated crops in the world providing the population with large amounts of protein and oil. In addition to its nutritional composition, soybean also contains biologically active compounds with potential health-promoting properties. The presence of these bioactives may be responsible for the lower incidence of chronic diseases in populations that consume a significant portion of soybeans in their diet. One group of soybeanderived bioactives are bioactive peptides and proteins including lunasin, Bowman-Birk inhibitor (BBI) and Kunitz-type trypsin inhibitor (KTI). The overall objective of this research was to develop a method of …

Protein, Methionine, And Cysteine Upregulation In Phaseolus Vulgaris ‘Black Turtle Bean’ Seeds Through Sulfur Fertilization At V2 And R2 Stages Of Growth, Hannah Paige Barry

Masters Theses

The purpose of this research was to increase protein, methionine, and cysteine content in Phaseolus vulgaris L., common bean in relation to the inhibitory compound tannin. Previous research has shown that sulfur fertilization increases total protein, methionine and cysteine content in various crops, but always in tandem with inhibitory compound increases. If successful, the resulting bean seed will have a better nutrient profile for malnourished populations around the world.

Granular gypsum was applied at 0 kg S ha^-1 [kilograms of sulfur per hectare], 10 kg S ha^-1, 20 kg S ha^-1, 40 kg S ha …

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Combinations Of Multiple Natural Antimicrobials With Different Mechanisms As An Approach To Control Listeria Monocytogenes, Savannah Grace Hawkins

Masters Theses

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, Marcel Schmidt

Masters Theses

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 D_72°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 HAV. …

Odor-Induced Taste Modifications In Teas, Rachel Elizabeth Isaacs

Masters Theses

Although odorants and tastants are perceived by two different sensory modalities, the perceived taste qualities of a solution may be modified with the addition of an odorant. While many studies have investigated odor-induced taste modifications in model solutions, there is a lack of conducted research examining odor-induced taste modifications in complex food systems. The research objective was to determine the effect of added vapor-phase stimuli on the perceived sweetness of a model solution and complex food system.

Eight vapor-phase stimuli (i.e. blueberry, caramel, ginger, honey, lemon, orange, peach, and strawberry) were selected for investigation. The study was conducted in two …

The Food Industry’S Perception Of Economically Motivated Adulteration And Related Risk Factors, Lindsay Colleen Murphy

Masters Theses

The United States of America has numerous safeguards in place to protect our food supply, including federal regulations and the food and beverage industry’s dedication to food safety. One of the issues that the food and beverage industry continuously battles is the prevalence of intentional adulteration. The Food Safety Modernization Act (FSMA) specifically addresses intentional adulteration and its sub-category of economically motivated adulteration (EMA) by requiring all facilities that supply food to the US to assess the vulnerabilities within their operation in order to prevent events that could cause public harm. The purposes of this study are threefold: (1) to …

High Intensity Ultrasound Assisted Extraction Of Oak Compounds For Accelerated Aging Of Wines And Whiskies, Lindsay Elizabeth Rogerson

Masters Theses

Aging of wines and whiskies in oak barrels is a timely and expensive process which could be reduced by acceleration. The purpose of this study is to identify if the use of high intensity ultrasound (HIUS) assisted extraction as an alternative, accelerated aging method could be utilized in the production of an oak extract to be used in wine and whiskies. HIUS will also be compared to reflux and room-temperature control extraction treatments as other accelerated aging methods. Secondary objectives of this study were to compare the heat treatment of charred and toasted staves donated by an anonymous donor, their …

Evaluation Of A Natural Antimicrobial-Based Sanitizer As An Alternative To Chlorine For Reducing Foodborne Pathogenic Bacteria On Organic Produce, Ellen Rebecca Simmons

Masters Theses

There is a need for the development of a “natural” sanitizing agent to reduce or eliminate foodborne pathogens that meets USDA organic standards, as an alternative to chlorine. The sanitizer needs to eliminate foodborne pathogens and prevent cross contamination in rinse liquids in the presence of organic matter. In this study, the focus was to evaluate a natural antimicrobial-based sanitizing (NABS) agent in rinse liquids to determine if it was capable of eliminating foodborne pathogens on organic produce through cross-contamination studies. Five-serovar/strain cocktails of pathogenic bacteria were combined to form an inoculum cocktail, which was used to inoculate the produce. …

Chemical Disinfectants For The Inactivation Of The Emerging Foodborne Aichi Virus, Andres Ignacio Arreaza

Masters Theses

Aichi virus (AiV) is an emerging virus responsible for gastroenteritis outbreaks worldwide. Improved decontamination methods are being researched to control AiV spread. The effects of common hard surface disinfectants including benzalkonium chloride (BAC), potassium peroxymonosulfate (KPMS), tribasic sodium phosphate (TSP) as well as sodium metasilicate (SMS) and calcium hypochlorite (Ca(ClO)₂) [calcium hypochlorite] against AiV need to be explored. The objective of this research was to determine their effects against AiV using suspension and carrier tests over various contact times at room temperature. Phosphate buffered saline (pH 7.2 as control), 0.64% BAC, 10% KPMS, 10% TSP, 0.16 and 0.3% …

Development And Evaluation Of Novel Vaccination Strategies For Campylobacter Control In Poultry, Xiang Liu

Masters Theses

Chicken is the primary natural host of Campylobacter, the leading bacterial cause of human enteritis in the US and other developed countries. Thus, mitigation of Campylobacter in chicken using innovative approaches, such as vaccination, will have a significant impact on food safety and public health. Our previous studies have demonstrated that the two outer membrane proteins, CmeC (the essential component of the CmeABC multi-drug efflux pump) and CfrA (a ferric enterobactin receptor), are feasible candidates for immune intervention against Campylobacter. DNA vaccine has appeared to offer various advantages for poultry, particularly when combined with in ovo vaccination. Chitosan-encapsulated …

Gallic Acid-Grafted Chitosan Films As Antioxidant Food Packaging, Ping Guo

Masters Theses

Chitosan is the second most abundant natural polysaccharide in the nature. Due to its biodegradability and film forming ability, chitosan has the potential to be used as an alternative to petroleum-based polymers for food packaging. The presence of a primary amine as well as primary and secondary hydroxyl groups enable chitosan to be chemically modified with various functional groups. Gallic acid (GA) is a natural occurring antioxidant (AOX), which can be grafted to chitosan using by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The first project deals with the effect of ethanol (EtOH) concentration on efficiency of grafting GA onto chitosan. …

Evaluation Of The Thermal Inactivation Kinetics Of Surrogate Vegetative Bacteria, Amber Lynne Parham Renix

Masters Theses

Microbial surrogates are defined as non-pathogenic organisms with behavioral and/or survival characteristics correlating to those of specific pathogens. The purpose of this study was to determine the thermal inactivation kinetics (D and z-values) of Lactobacillus bulgaricus ATCC 11842, Lactobacillus fructivorans ATCC 8288, Lactobacillus plantarum ATCC 4008, Listeria innocua ATCC 33091, ATCC 51742, and 11/97, and Staphylococcus carnosus CS-299 as potential surrogates for hepatitis A virus (HAV; D_72°C = 0.9 min). Additionally, the effect of sub-lethal heat on increasing the thermotolerance of L. bulgaricus was investigated. All strains were tested in phosphate buffered saline (PBS) as a …

The Effect Of Lecithin On Inactivation By Eugenol Of Escherichia Coli O157:H7, Sasha Marie Wilkinson

Masters Theses

Many essential oils and their components are known to have antimicrobial activity. However, their strong aroma, flavor, and hydrophobic nature make them difficult to incorporate into food products. New methods to improve antimicrobial activity at reduced concentrations and/or reduce the influence of food components on antimicrobial activity are needed. In this study, the objective was to combine the emulsifier soy lecithin with eugenol in an attempt to enhance the activity of the latter against the foodborne pathogen Escherichia coli O157:H7.

Eugenol was added to a pH 7.2 sodium phosphate buffer (PBS), PBS with 0.03% (v/v) tryptic soy broth (TSB), PBS …

Preparation And Characterization Of Acid-Induced Gels At Ph 1.0-4.0 And Thermal-Stable Dispersions At Ph 5.5-6.0 Using Preheated Whey Protein, Kangkang Li

Masters Theses

Whey protein (WP) is a good source for producing protein-rich products, including satiety foods and beverages. Thermal aggregation of WP during sterilization or pasteurization impacts food quality important to shelf-stable beverages. Preheating WP improves the thermal stability at neutral acidity, and forming complexes with other molecules to provide charge and/or steric hindrance can be used to improve thermal stability of WP at acidic conditions. Conversely, aggregation properties of preheated WP upon acidification can be used to create unique functional properties. Therefore, studying properties of preheated WP can broaden its application in the food industry.

Gelation of preheated WP and pectin …

Sanitization Effectiveness Of Alkaline-Dissolved Essential Oils As Organic Produce Washing Solutions, Marion Lewis Harness Iii

Masters Theses

Produce is often rinsed immediately post-harvest to remove dirt and debris. Rinse water can be a point of cross-contamination if no antimicrobials are present. While plant essential oils (EOs) are recognized as antimicrobials, their hydrophobicity makes them difficult to implement in rinsing solutions. In this study, the efficacy of emulsified EOs were examined against Salmonella on the surface of cherry tomatoes and Escherichia coli O157:H7 on the surface of baby spinach. Contaminated produce samples were rinsed in an emulsions of clove bud oil or thyme oil at 0.2 and 0.5% (v/v), as well as free chlorine at 200 ppm and …

Synergistic Interfacial Properties Of Casein And Small Molecule Surfactants For Fabrication Of Essential Oil Nanoemulsions, Dan Su

Masters Theses

Nanoemulsions of essential oils are important for delivery of flavors and antimicrobial preservatives in food systems. The overall goal of this work was to study the formation and properties of essential oil nanoemulsions fabricated with sodium caseinate (NaCas) or its hydrolysates and small molecule surfactants (SMSs). The first group of lemon oil nanoemulsion was prepared with NaCas and Tween 20 using a phase inversion temperature (PIT) method. The combination of NaCas and Tween 20 reduced the turbidity and droplet dimension of emulsions than using them individually. Heating at 90 °C for >1 h resulted in transparent nanoemulsions for samples with …

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 …

The Effect Of Soluble Soybean Polysaccharide On Crystallization Behavior Of Lactose, Xueqian Shi

Masters Theses

Lactose can be recovered from cheese whey permeate concentrate by crystallization, and improving the recovery efficiency and purity of lactose crystals is significant to the profitability of the dairy industry. Lactose is also the major component in spray-dried dairy ingredients such as milk and whey powder. Lactose in spray-dried powder is amorphous and causes quality problems such as caking due to the crystallization of amorphous lactose during storage. Technologies are thus needed to improve the crystallinity of spray-dried lactose. In this study, soluble soybean polysaccharide (SSPS) was studied for the effects on lactose crystallization in aqueous solutions and during spray …

Control Of Emerging Foodborne Viruses Using Cranberry Extracts And Chemical Sanitizers, Snigdha Nitin Sewlikar

Masters Theses

Human norovirus (HNoV), hepatitis A virus (HAV) and Aichi virus (AiV) outbreaks that cause severe foodborne disease are on the rise globally. Strategies to prevent and mitigate the spread of these viral infections need to be investigated. HNoV, HAV and AiV are known to be resistant to most of the conventionally used chemical inactivation methods. Cranberry juice (CJ) and cranberry proanthocyanidins (C-PAC) have demonstrated antimicrobial and anti-inflammatory properties. CJ and C-PAC have been shown to exhibit antiviral activities against HNoV surrogates, feline calicivirus (FCV-F9) and murine norovirus (MNV-1) at room temperature. Hence, the objectives of this research were (1) To …

Transfer And Survival Of Microorganisms To Produce From Surface Irrigation Water, Stuart Jamison Gorman

Masters Theses

Surface water irrigation sources are widely used for fruit and vegetable crop production in the United States. Surface water is inherently prone to direct and indirect contamination with animal fecal material. Hence, the microbial quality of surface water sources can be highly variable. Water used for irrigation is considered a common source for produce contamination. In addition to this, fruits and vegetables are commonly consumed fresh or minimally processed, thus emphasizing the need for preventative measures in production of fresh produce. This study will examine transfer from naturally contaminated irrigation water to cantaloupes using drip and overhead spray irrigation methods. …