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Dissertations, Theses, & Student Research in Food Science and Technology

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Host-Microbe-Diet Interplay: Dietary Modulation Of The Gut Microbiota In Relation To Health, Inés Martínez Aug 2012

Host-Microbe-Diet Interplay: Dietary Modulation Of The Gut Microbiota In Relation To Health, Inés Martínez

Dissertations, Theses, & Student Research in Food Science and Technology

Vertebrates are associated with trillions of bacteria, with the densest populations residing in the large intestine. The symbiosis between vertebrates and their gut microbiota has resulted in important implications of the gut microbiome on host health. Diet is an important factor that shapes gut microbiota composition, and because of the interplay between host-microbiome-diet, dietary strategies that modulate gut microbiome structure are deemed a relevant tool to improve host health. However, gaps in knowledge exist with respect to these interactions, and it is essential to obtain a mechanistic understanding of how these relations take place to develop successful therapeutic strategies that ...


Validation Of Thermal Processing To Control Salmonella Spp. And Clostridium Perfringens During Prime Rib Preparation From Intact And Non-Intact Meat, Maria A. Calle May 2012

Validation Of Thermal Processing To Control Salmonella Spp. And Clostridium Perfringens During Prime Rib Preparation From Intact And Non-Intact Meat, Maria A. Calle

Dissertations, Theses, & Student Research in Food Science and Technology

Beef prime rib is a delicacy cooked at low temperatures for long period and extended hot holding prior to consumption. Due to the potential survival and outgrowth of foodborne pathogens, this process may pose a public health risk. Considering an increase in the availability of non-intact beef, the microbial safety of the preparation of prime rib from intact and mechanically tenderized beef was evaluated.

In the first study, lethality of the prime rib (from intact and non-intact, blade tenderized beef) cooking process to Salmonella spp. was evaluated. Boneless beef rib eye was surface inoculated with a five-strain cocktail of Salmonella ...


Characterization Of Igg And Ige Binding To Parvalbumin Derived From Commercially Important Fish Species, Poi-Wah Lee May 2012

Characterization Of Igg And Ige Binding To Parvalbumin Derived From Commercially Important Fish Species, Poi-Wah Lee

Dissertations, Theses, & Student Research in Food Science and Technology

Parvalbumin is a calcium-binding muscle protein that is present in all vertebrates. Despite being a pan-allergen in fish and frog, fish-specific IgE and antiparvalbumin IgG antibodies displayed varying cross-reactivity among fish species. In this research, the parvalbumin-binding characteristics of several antibodies were investigated, including 3 IgG antibodies against frog, carp, and cod parvalbumins, and human IgE.

By immunoassay and IgG-immunoblotting, 3 antiparvalbumin antibodies revealed inconsistent specificity among 29 raw fish muscle extracts, which may be partially attributed to the decreased levels of fish muscle parvalbumin from anterior to posterior positions. Parvalbumin-binding by antibodies was unaffected in 112 days of frozen-stored ...


Influence Of Dietary Fibers And Whole Grains On Fecal Microbiota During In Vitro Fermentation, Junyi Yang May 2012

Influence Of Dietary Fibers And Whole Grains On Fecal Microbiota During In Vitro Fermentation, Junyi Yang

Dissertations, Theses, & Student Research in Food Science and Technology

There has been a dramatic increase in obesity, which presents a risk of many chronic health problems. Recent studies have shown that obese individuals harbor an abnormal gut microbiota (dysbiosis), which has sparked interest in the gut microbiota as a target for weight management. Dietary fiber and whole grains that can be metabolized by gut microbiota have been shown to promote the growth of beneficial bacteria in the gut. Increased consumption of dietary fiber and whole grains may improve host / gut microbiota interactions in obesity and other metabolic diseases by normalizing gut dysbiosis. The present thesis describes two research projects ...


Biological Analysis Of Prebiotics In Various Processed Food Matrices, Kristina Elise Moore Dec 2011

Biological Analysis Of Prebiotics In Various Processed Food Matrices, Kristina Elise Moore

Dissertations, Theses, & Student Research in Food Science and Technology

The addition of prebiotic to a variety of food products has become a more common occurrence in recent years. Although research on the stability of prebiotics has been conducted, knowledge of the stability of prebiotics in processed foods is limited. The purpose of this research was to determine the biological stability of five prebiotics in a variety of food matrices when processed under various conditions. A biological test, the prebiotic activity assay, was used to test for stability of six food products (muffin, cookie, granola bar, breakfast cereal, sports drink, and bread) containing five different prebiotics (fructooligosaccharides (FOS), inulin, galactooligosaccharides ...


Adaptation And Validation Of Food Product Specific Analytical Methods For Monitoring Prebiotics Present In Different Types Of Processed Food Matrices, Rebbeca M. Duar Dec 2011

Adaptation And Validation Of Food Product Specific Analytical Methods For Monitoring Prebiotics Present In Different Types Of Processed Food Matrices, Rebbeca M. Duar

Dissertations, Theses, & Student Research in Food Science and Technology

Prebiotic carbohydrates are now added to a variety of processed foods to beneficially affect the gut microbial composition and activities. However, published data remain limited on the stability of prebiotics during food processes, such as baking, extrusion, pasteurization, high temperature heating, low pH condition, etc. As the complexity of the food matrix may also affect the ability to test for prebiotics, product specific analytical methods, including UV-vis spectroscopy, GC and HPLC, were developed and validated to monitor the stability of FOS, inulin and GOS in different types of processed food (breakfast cereal, cookie, muffin, sports drink and a nutritional bar ...


Identification And Characterization Of Putative Allergens In Pecan Species, Jelena Spiric Dec 2011

Identification And Characterization Of Putative Allergens In Pecan Species, Jelena Spiric

Dissertations, Theses, & Student Research in Food Science and Technology

The identification and characterization of soluble pecan proteins was found to be qualitatively dependent on the chemical characteristics of the extraction buffer that also had a significant influence on the total protein content of an extract. The ionic strength of the extraction buffer had a greater impact on protein extractability than pH. A high salt phosphate buffer (0.01 M PBS, 1M NaCl, pH 7.2) was used as an optimal extraction solution that allowed remarkable detection of clinically relevant allergens.

The 2S albumin family of seed storage proteins has been shown to be one of the most stable allergens ...


Studies On The Adherence Properties Of Plant Lectins And Bacterial Adhesins And Their Inhibition By Prebiotic Oligosaccharides And Bovine Colostrum Fractions, Maria X. Maldonado-Gomez Nov 2011

Studies On The Adherence Properties Of Plant Lectins And Bacterial Adhesins And Their Inhibition By Prebiotic Oligosaccharides And Bovine Colostrum Fractions, Maria X. Maldonado-Gomez

Dissertations, Theses, & Student Research in Food Science and Technology

To initiate colonization and infection, most microbial pathogens must first recognize and adhere to cells in the host tissues. Adherence inhibition, therefore, can be used as a strategy for preventing infectious disease. In this research, we developed a simplified model using plant lectins and HEp-2 tissue culture cells to simulate bacterial adhesins-receptors interactions. The effect of lectin ligands and two prebiotic carbohydrates, galactooligosaccharide (GOS) and polydextrose (PDX) was measured with this approach. Lectins that were able to bind to the target cells were inhibited in the presence of the cognate ligands and at least one of the prebiotic carbohydrates. The ...


Effect Of Sodium Nitrite, Sodium Erythorbate And Organic Acid Salts On Germination And Outgrowth Of Clostridium Perfringens Spores In Ham During Abusive Cooling, Mauricio A. Redondo Sep 2011

Effect Of Sodium Nitrite, Sodium Erythorbate And Organic Acid Salts On Germination And Outgrowth Of Clostridium Perfringens Spores In Ham During Abusive Cooling, Mauricio A. Redondo

Dissertations, Theses, & Student Research in Food Science and Technology

The effect of sodium nitrite (NaNO2), sodium erythorbate, sodium chloride (NaCl) and organic acid salts (potassium lactate and sodium diacetate) on C. perfringens spore germination and outgrowth in ham was evaluated. The research was divided in two parts. The first experiment consisted of potential C. perfringens spore germination and outgrowth in ham containing combinations of NaNO2 (0, 50, 100, 150 or 200 ppm) and sodium erythorbate (0 or 557 ppm) during cooling. This experiment included the evaluation of residual nitrite levels as affected by temperature (heat shock at 75°C for 20 min and subsequent cooling from 54 ...


Pulsed Electric Field (P.E.F) And Pectinase For The Extraction Of Polyphenols From Grape Pomace And Peel, Julien Khalil Aug 2011

Pulsed Electric Field (P.E.F) And Pectinase For The Extraction Of Polyphenols From Grape Pomace And Peel, Julien Khalil

Dissertations, Theses, & Student Research in Food Science and Technology

Grapes are an important source of bioactive compounds such as gallic acid, resveratrol, and catechin. The consumption of grapes is associated with a lower risk of diseases such as cardiovascular diseases and some types of cancer. Grape pomace and skins are good sources of many phytochemicals known for their antioxidant potential.

In this research, the peel of the Chilean “Flame” grape cultivar and the pomace of St. Croix, Frontenac and St. Pepin grape cultivars were subjected to a pulsed electric field (5 KV, 1 μFarad, 20 Pulses) and to an enzymatic treatment (Pectinase, 5KU). The total phenolic content, determined in ...


Extraction Of Bioactive Compounds From Whole Red Cabbage And Beetroot Using Pulsed Electric Fields And Evaluation Of Their Functionality, Valli Kannan May 2011

Extraction Of Bioactive Compounds From Whole Red Cabbage And Beetroot Using Pulsed Electric Fields And Evaluation Of Their Functionality, Valli Kannan

Dissertations, Theses, & Student Research in Food Science and Technology

Application of high voltage pulsed electric fields (PEF) to plant tissues increases porosity of the plant cells, enhancing juice extraction from fruits and vegetables. Red cabbage and beetroot are rich sources of bioactive compounds anthocyanins and betalains, respectively. Pulsed electric field (red cabbage: 1 kV/cm electric field strength, 0.66 µF and 20 pulses; red beets: 1.5 kV/cm electric field strength, 0.66 µF and 20 pulses) was applied to whole red cabbage and beetroot to enhance juice extraction. Total polyphenols, anthocyanins (red cabbage), betalains (beetroot) and total antioxidant activity (ABTS and DPPH) of the extracted juice ...


Effects Of Malting And Fermentation On The Composition And Functionality Of Sorghum Flour, Onesmo N.O. Mella May 2011

Effects Of Malting And Fermentation On The Composition And Functionality Of Sorghum Flour, Onesmo N.O. Mella

Dissertations, Theses, & Student Research in Food Science and Technology

Sorghum is an ancient crop grown almost everywhere in the world and used for different purposes. In the U.S, and other developed countries, sorghum is used largely for animal feeding. In developing countries, especially in Africa and Asia, it is used primarily as human food.

Sorghum is a dependable food crop in Tanzania and its production and use ranks second after maize. Different traditional methods including malting and fermentation have been used in addition to decorticating and milling to process sorghum for the purpose of providing diverse materials. However, sorghum has major drawbacks of poor starch and protein digestibilities ...


Adaptation And Validation Of Existing Analytical Methods For Monitoring Prebiotics Present In Different Types Of Processed Food Matrices, Pei Tze Ang May 2011

Adaptation And Validation Of Existing Analytical Methods For Monitoring Prebiotics Present In Different Types Of Processed Food Matrices, Pei Tze Ang

Dissertations, Theses, & Student Research in Food Science and Technology

Interest in resistant starch (RS) as a prebiotic is increasing due to its putative impacts on the gastrointestinal microbiome and thus colon health. Application of RS as a food ingredient is also increasing because of its unique functionality. However, a major obstacle when correlating RS containing food systems to the potential health benefits is the discrepancy in the analytical tests applied and the limitations of those methods used throughout the literature. Therefore, the Megazyme resistant starch assay was adapted and developed to monitor RS present in different types of products commonly consumed in the United States, including an extruded ready-to-eat ...


Adherence Inhibition Of Cronobacter Sakazakii And Other Pathogens By Prebiotic Oligosaccharides, Plant Extracts, And Other Naturally Derived Molecules, Maria I. Quintero Apr 2011

Adherence Inhibition Of Cronobacter Sakazakii And Other Pathogens By Prebiotic Oligosaccharides, Plant Extracts, And Other Naturally Derived Molecules, Maria I. Quintero

Dissertations, Theses, & Student Research in Food Science and Technology

For most bacterial pathogens, adherence of the bacterium to the surface of the host cell tissue is a necessary first step for colonization and infection. Agents that inhibit adherence, therefore, could be useful for preventing infections. The goal of this research was to assess the anti-adherent activity of several food-grade prebiotic carbohydrates, plant extracts, and other naturally-derived molecules against enteric pathogens. First, the antiadherent effect of galactooligosaccharides (GOS), polydextrose (PDX), and a GOS-PDX blend was tested against two strains of Cronobacter “Enterobacter” sakazakii. When measured microscopically or by cultural methods, significant reductions in adherence (56% and 71%, respectively) of C ...


Evaluation And Analysis Of Beef Contamination By Low Levels Of Ammonia, Sely Prajitna Apr 2011

Evaluation And Analysis Of Beef Contamination By Low Levels Of Ammonia, Sely Prajitna

Dissertations, Theses, & Student Research in Food Science and Technology

Leakage of ammonia in food facilities has been known to occur in the past. Ammonia leaks often lead to food contamination in food plants and can cause illness among consumers who accidentally consume the food products contaminated with high levels of ammonia. Therefore, a rapid, simple yet accurate method has to be established for on-site ammonia level screening in food plants to ensure the food is safe. One of the primary objectives in this study was to verify and optimize an ion selective electrode (ISE) method for its accuracy and reproducibility in determining ammonia in meat. Different extraction procedures (blending ...


Electromagnetic And Heat Transfer Modeling Of Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai Apr 2011

Electromagnetic And Heat Transfer Modeling Of Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai

Dissertations, Theses, & Student Research in Food Science and Technology

Microwave (MW) ovens are used extensively for heating a variety of not-ready-to-eat food products. It is vital to achieve target temperature uniformly throughout the food to inactivate foodborne pathogens to assure safety. Non-uniform heating of foods in microwave ovens is the major concern in assuring microbiological safety of such products. The non-uniform heating of foods in domestic microwave ovens is due to complex interactions of microwaves with foods. A comprehensive coupled electromagnetic and heat transfer model was developed using finite-difference time-domain based numerical method to understand the complex interaction of microwaves with foods. Simulation parameters such as cell size, heating ...


Examination Of Egg White Proteins And Effects Of High Pressure On Select Physical And Functional Properties, Andrew Hoppe Dec 2010

Examination Of Egg White Proteins And Effects Of High Pressure On Select Physical And Functional Properties, Andrew Hoppe

Dissertations, Theses, & Student Research in Food Science and Technology

Egg white proteins have become an important and desirable ingredient to the food industry due to their functional properties which include gelling, foaming, and emulsification. Egg white is also well recognized as an excellent source of nutrition. The goal of this work was to determine the effects of high pressure (HP) treatment on egg white proteins. Specifically, experiments were conducted using Raman spectroscopy and pepsin digestibility to investigate structural changes. Pressure treatment at 400 to 800 MPa (5 minutes at 4°C) resulted in increased pepsin digestibility of egg white proteins ovalbumin, ovotransferrin, and lysozyme compared to heat-treated (85 to ...


The Bifidogenicity Of The Prebiotic Galactooligosaccharides, Lauren M. G. Davis Dec 2010

The Bifidogenicity Of The Prebiotic Galactooligosaccharides, Lauren M. G. Davis

Dissertations, Theses, & Student Research in Food Science and Technology

The goal of this research was to determine the effect of different doses of galactooligosaccharide (GOS) on the fecal microbiota of healthy adults, with a focus on bifidobacteria. The study was designed as a single-blinded study, with eighteen subjects consuming GOS-containing chocolate chews at four increasing dosage levels; 0, 2.5, 5.0, and 10.0 g. Subjects consumed each dose for 3 weeks, with a two-week baseline period preceding the study and a two-week washout period at the end. Cultural methods were used for bifidobacteria, Bacteroides, enterobacteria, enterococci, lactobacilli, and total anaerobes; culture-independent methods included denaturing gradient gel electrophoresis ...


Identification And Characterization Of Salmonella Serotypes Isolated From Pork And Poultry From Commercial Sources, Yulie Edith Meneses-GonzáLez Nov 2010

Identification And Characterization Of Salmonella Serotypes Isolated From Pork And Poultry From Commercial Sources, Yulie Edith Meneses-GonzáLez

Dissertations, Theses, & Student Research in Food Science and Technology

Salmonella is one of the leading causes of foodborne illness worldwide, and it is estimated that 1.4 million infections occur annually in the U.S. alone. The Premi®Test Salmonella (PTS), is a potential tool for rapid detection and identification of Salmonella serovars. The objective of this project was to evaluate the use of the PTS system as a serotyping tool to identify pork and poultry isolates obtained from vertically integrated operations and to characterize their antibiotic resistance. Two hundred isolates were evaluated. All isolates were serotyped using the traditional Kaufmann-White scheme and the PTS system. Among the isolates ...


Development Of An Enzyme-Linked Immunosorbent Assay (Elisa) For The Detection Of Pistachio Residues In Processed Foods, Pei Wen Lim Nov 2010

Development Of An Enzyme-Linked Immunosorbent Assay (Elisa) For The Detection Of Pistachio Residues In Processed Foods, Pei Wen Lim

Dissertations, Theses, & Student Research in Food Science and Technology

Pistachios (Pistacia vera) are popular snacks and consumption of pistachios is notably increasing due to their usage as ingredients for confections, ice cream, and baked goods. The increased consumption of pistachios may lead to a higher frequency of allergic sensitization and an increased prevalence of allergic reactions to pistachios. Trace amounts of undeclared pistachio allergens can pose serious health risks for food-allergic consumers, including severe anaphylactic reactions. A highly sensitive analytical method, sandwich-type enzyme-linked immunosorbent assay (ELISA) is applied as a critical tool for food manufacturers and food scientists to detect minute amounts of allergenic food residues in processed foods ...


The Effects Of High Pressure Processing On Peanut Sauce Inoculated With Salmonella, Tara K. Stiles Jul 2010

The Effects Of High Pressure Processing On Peanut Sauce Inoculated With Salmonella, Tara K. Stiles

Dissertations, Theses, & Student Research in Food Science and Technology

Recent Salmonella outbreaks have prompted the need for new processing options for peanut products. Traditional heating kill-steps have shown to be ineffective in lipid-rich matrices such as peanut products. High pressure processing is one such option for peanut sauce because it has a high water activity, which has proved to be a large contributing factor in microbial lethality due to high pressure processing. Four different formulations of peanut sauce were inoculated with a five strain Salmonella cocktail and high pressure processed. Results indicate that increasing pressure or increasing hold time increases log10 reductions. The Weibull model was fitted to ...


Development Of Fourier Transform Mid-Infrared Spectroscopy As A Metabolomic Technique For Characterizing The Protective Properties Of Grain Sorghum Against Oxidation, Emily Diane Sitorius May 2010

Development Of Fourier Transform Mid-Infrared Spectroscopy As A Metabolomic Technique For Characterizing The Protective Properties Of Grain Sorghum Against Oxidation, Emily Diane Sitorius

Dissertations, Theses, & Student Research in Food Science and Technology

DEVELOPMENT OF FOURIER TRANSFORM MID-INFRARED SPECTROSCOPY AS A METABOLOMIC TECHNIQUE FOR CHARACTERIZING THE PROTECTIVE PROPERTIES OF GRAIN SORGHUM AGAINST OXIDATION

Emily D. Sitorius, M.S. University of Nebraska, 2010 Advisor: Vicki L. Schlegel

Cellular oxidative damage has been linked to many chronic diseases including Alzheimer’s, diabetes, and cancer. Recent studies have shown that foods rich in antioxidants (i.e., grain sorghum) can protect against oxidative stress and thus reduce the risk of disease. However, a significant gap in knowledge exists in that dietary antioxidants are usually characterized by methods that determine free radical and reactive oxygen species’ scavenging capacity ...


Dynamic Predictive Model For The Growth Of Salmonella Spp. In Liquid Whole Egg And Risk Evaluation Of Egg White Hydrolysates Manufacturing Process For Spore Formers: Bacillus Cereus And Clostridium Perfringens., Aikansh Singh May 2010

Dynamic Predictive Model For The Growth Of Salmonella Spp. In Liquid Whole Egg And Risk Evaluation Of Egg White Hydrolysates Manufacturing Process For Spore Formers: Bacillus Cereus And Clostridium Perfringens., Aikansh Singh

Dissertations, Theses, & Student Research in Food Science and Technology

A dynamic model for the growth of Salmonella spp. in liquid whole egg under continuously varying temperature was developed and validated. A primary model (Baranyi model) was fitted to each temperature growth data and corresponding maximum growth rates were estimated. Pseudo-R2 values were greater than 0.97 for primary models. The maximum growth rates obtained from each primary model were then plotted against temperature and modeled using the modified Ratkowsky model. The pseudo-R2 and root mean square error were 0.99 and 0.06 h-1, respectively for the secondary model. A dynamic model for the prediction of ...


Use Of Near-Infrared Spectroscopy For Qualitative And Quantitative Analyses Of Grains And Cereal Products, Panjama Cheewapramong Dec 2007

Use Of Near-Infrared Spectroscopy For Qualitative And Quantitative Analyses Of Grains And Cereal Products, Panjama Cheewapramong

Dissertations, Theses, & Student Research in Food Science and Technology

The purpose of the first part of the study was to develop a simplified near-infrared reflectance (NIR) spectroscopy method for detecting insect larvae in individual wheat kernels. Discriminant analysis, based on Mahalanobis distances calculated from log 1/R data at only four discrete wavelengths, yielded better results for classification of sound and insect infested wheat kernels than principal component analysis (PCA) using the spectral region from 1100 to 1900 nm. This simplified technique was then used to detect 3- and 4-week-old larvae of granary and maize weevils in wheat kernels. A model developed from a calibration set containing sound kernels ...


Effect Of Prebiotic Oligosaccharides On Enteropathogenic Escherichia Coli Adherence, Kari Shoaf Nov 2006

Effect Of Prebiotic Oligosaccharides On Enteropathogenic Escherichia Coli Adherence, Kari Shoaf

Dissertations, Theses, & Student Research in Food Science and Technology

Antiadhesion therapy has been found to be a very promising means to prevent and treat infections in the respiratory, urinary, and gastrointestinal tract. Despite the considerable research interest in antiadhesives, relatively little is known about the ability of commercial dietary oligosaccharides, such as prebiotics, to inhibit pathogen adherence. The goal of this research was to determine if commercially available prebiotic oligosaccharides could function as antiadhesive agents against enteropathogenic E. coli (EPEC).

To investigate the ability of prebiotics to inhibit EPEC adherence, inhibition assays were performed by comparing adherence rates of EPEC on HEp-2 and Caco-2 cells in the presence of ...


Factors Affecting The B-Vitamin Content Of Cottage Cheese, Gary Dean Reif Sep 1964

Factors Affecting The B-Vitamin Content Of Cottage Cheese, Gary Dean Reif

Dissertations, Theses, & Student Research in Food Science and Technology

The purpose of this study was to investigate the vitamin content of Cottage cheese and to study the factors which may alter the content of certain B-vitamins. The specific objectives were as follows:

  1. To determine the niacin, B6, B12 and folic acid content of skimmilk and Cottage cheese and the retention of those vitamins in the curd from the milk.
  2. To study the synthesis of niacin, B6, B12 and folic acid during the 16-hr setting period used in making Cottage cheese, and to determine whether the vitamin synthesis by the starter was partly responsible for the ...