Food Science Commons^™

The Gut Mycobiome Of The Human Microbiome Project Healthy Cohort, Andrea K. Nash, Thomas A. Auchtung, Matthew C. Wong, Daniel P. Smith, Jonathan R. Gesell, Matthew C. Ross, Christopher J. Stewart, Ginger A. Metcalf, Donna M. Muzny, Richard A. Gibbs, Nadim J. Ajami, Joseph F. Petrosino

Department of Food Science and Technology: Faculty Publications

Background: Most studies describing the human gut microbiome in healthy and diseased states have emphasized the bacterial component, but the fungal microbiome (i.e., the mycobiome) is beginning to gain recognition as a fundamental part of our microbiome. To date, human gut mycobiome studies have primarily been disease centric or in small cohorts of healthy individuals. To contribute to existing knowledge of the human mycobiome, we investigated the gut mycobiome of the Human Microbiome Project (HMP) cohort by sequencing the Internal Transcribed Spacer 2 (ITS2) region as well as the 18S rRNA gene.

Results: Three hundred seventeen HMP stool samples were …

Lifestyle And Horizontal Gene Transfer- Mediated Evolution Of Mucispirillum Schaedleri, A Core Member Of The Murine Gut Microbiota, Alexander Loy, Carina Pfann, Michaela Steinberger, Buck Hanson, Simone Herp, Sandrine Brugiroux, João Carlos Gomes Neto, Mark V. Boekschoten, Clarissa Schwab, Tim Urich, Amanda E. Ramer-Tait, Thomas Rattei, Bärbel Stecher, David Berry

Department of Food Science and Technology: Faculty Publications

Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals and has been suggested to be a pathobiont, a commensal that plays a role in disease. In order to gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and performed physiological experiments to test traits predicted by its genome. Although described as a mucus inhabitant, M. schaedleri has limited capacity for degrading host-derived mucosal glycans and other complex polysaccharides. Additionally, M. schaedleri reduces nitrate and expresses systems for scavenging oxygen and reactive oxygen species in vivo, …

Isolation And Genetic Identification Of Spore-Forming Bacteria Associated With Concentrated-Milk Processing In Nebraska, Bismarck Antonio Martinez, Jayne E. Stratton, Andreia Bianchini

Department of Food Science and Technology: Faculty Publications

Spore-forming bacteria are heat-resistant microorganisms capable of surviving and germinating in milk after pasteurization. They have been reported to affect the quality of dairy products by the production of enzymes (lipolytic and proteolytic) under low-temperature conditions in fluid milk, and have become a limiting factor for milk powder in reaching some selective markets. The objective of this research was to isolate and identify the population of spore-forming bacteria (psychrotrophic and thermophilic strains) associated with concentrated milk processing in Nebraska. During 2 seasons, in-process milk samples from a commercial plant (raw, pasteurized, and concentrated) were collected and heat-treated (80°C/12 min) to …

Peanut Allergen Threshold Study (Pats): Novel Single-Dose Oral Food Challenge Study To Validate Eliciting Doses In Children With Peanut Allergy, Jonathan O'B. Hourihane, Katrina J. Allen, Wayne G. Shreffler, Gillian Dunngalvin, Julie A. Nordlee, Giovanni A. Zurzolo, Audrey Dunngalvin, Lyle C. Gurrin, Joseph L. Baumert, Steve L. Taylor

Department of Food Science and Technology: Faculty Publications

Background: Eliciting doses (EDs) of allergenic foods can be defined by the distribution of threshold doses for subjects within a specific population. The ED₀₅ is the dose that elicits a reaction in 5% of allergic subjects. The predicted ED₀₅ for peanut is 1.5 mg of peanut protein (6 mg of whole peanut).

Objective: We sought to validate the predicted peanut ED05 (1.5 mg) with a novel single-dose challenge.

Methods: Consecutive eligible children with peanut allergy in 3 centers were prospectively invited to participate, irrespective of previous reaction severity. Predetermined criteria for objective reactions were used …

Eugenol Nanoencapsulated By Sodium Caseinate: Physical, Antimicrobial, And Biophysical Properties, Yue Zhang, Kang Pan, Qixin Zhong

Department of Food Science and Technology: Faculty Publications

To improve the application of essential oils as natural antimicrobial preservatives, the objective of the present study was to determine physical, antimicrobial, and biophysical properties of eugenol after nanoencapsulation by sodium caseinate (NaCas). Emulsions were prepared by mixing eugenol in 20.0 mg/mL NaCas solution at an overall eugenol content of 5.0–137.9 mg/mL using shear homogenization. Stable emulsions were observed up to 38.5 mg/mL eugenol, which had droplet diameters of smaller than 125 nm at pH 5–9 after ambient storage for up to 30 days. The encapsulated eugenol had similar minimal inhibitory and minimal bactericidal concentrations as free eugenol against Escherichia …

A Real-Time Pcr Assay For Accurate Quantification Of The Individual Members Of The Altered Schaedler Flora Microbiota In Gnotobiotic Mice, João Carlos Gomez-Neto, Sara Mantz, Kyler Held, Rohita Sinha, Rafael R. Segura Munoz, Robert Schmaltz, Andrew K. Benson, Jens Walter, Amanda E. Ramer-Tait

Department of Food Science and Technology: Faculty Publications

Changes in the gastrointestinal microbial community are frequently associated with chronic diseases such as Inflammatory Bowel Diseases. However, understanding the relationship of any individual taxon within the community to host physiology is made complex due to the diversity and individuality of the gut microbiota. Defined microbial communities such as the Altered Schaedler Flora (ASF) help alleviate the challenges of a diverse microbiota by allowing one to interrogate the relationship between individual bacterial species and host responses. An important aspect of studying these relationships with defined microbial communities is the ability to measure the population abundance and dynamics of each member. …

Endurance Exercise Increases Intestinal Uptake Of The Peanut Allergen Ara H 6 After Peanut Consumption In Humans, Lonneke M. Janssenduijghuijsen, Klaske Van Norren, Sander Grefte, Stef J. Koppelman, Kaatje Lenaerts, Jaap Keijer, Renger F. Witkamp, Harry J. Wichers

Department of Food Science and Technology: Faculty Publications

Controlled studies on the effect of exercise on intestinal uptake of protein are scarce and underlying mechanisms largely unclear. We studied the uptake of the major allergen Ara h 6 following peanut consumption in an exercise model and compared this with changes in markers of intestinal permeability and integrity. Ten overnight-fasted healthy non-allergic men (n = 4) and women (n = 6) (23 +/- 4 years) ingested 100 g of peanuts together with a lactulose/rhamnose (L/R) solution, followed by rest or by 60 min cycling at 70% of their maximal workload. Significantly higher, though variable, levels of Ara h 6 …

Risk Assessment And Research Synthesis Methodologies In Food Safety: Two Effective Tools To Provide Scientific Evidence Into The Decision Making Process, Juan E. Ortuzar

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

The food supply chain is a complex and diverse system. Some food products need minimum processing to reach the consumers, while others involve several different processes, countries and suppliers, can take several months to be on the table of the end consumer. Regarding food safety, the public health of consumers is at stake and the consequences of outbreaks could prove disastrous. This has been recognized as a matter of global importance for the food industry and authorities around the world since several efforts to improve quality, safety and trade of food have arisen since the early 1960s. The birth of …

Edible Insects As A Source Of Food Allergens, Lee Palmer

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

Increasing global population increasingly limited by resources has spurred interest in novel food sources. Insects may be an alternative food source in the near future, but consideration of insects as a food requires scrutiny due to risk of allergens. Currently, the insect Dactylopius coccus, known as cochineal, is used to produce carmine, a natural red pigment used in food, which has caused allergic reactions. This study investigated allergens of cochineal focusing on purification from the pigment. Mass spectrometry identified a previously described major allergen of cochineal and a tropomyosin, although further work is required.

Tropomyosin is a major cross-reactive allergen …

Formation Of Bioactive-Carrier Hollow Solid Lipid Micro- And Nanoparticles, Junsi Yang

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

In recent years, bioactive lipids (e.g., carotenoids, phytosterols, and tocopherols) have attracted a lot of interest to develop health and wellness promoting foods and beverages. However, bioactive lipids are water-insoluble and degrade easily during processing and storage, making their addition into foods and beverages challenging.

The main objective of this thesis was to develop a novel green process to form bioactive lipid-carrier hollow solid lipid micro- and nanoparticles using supercritical carbon dioxide (SC-CO₂). Specific objectives were to develop hollow solid lipid micro- and nanoparticles using SC-CO₂ technology, and to load the hollow solid lipid micro- and nanoparticles …

Studies On Asparagine In Nebraska Wheat And Other Grains, Sviatoslav Navrotskyi

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

Understanding of the contribution of environmental and genetic factors on the chemical composition of different grains is a critical issue in the area of food safety of cereal products. Numerous studies have reported that asparagine can form acrylamide, a toxic and potentially carcinogenic precursor compound, during a Milliard reaction. Therefore, studying the environmental and genetic effects that contribute to accumulation of asparagine in wheat and proso millet lines, which were grown in the state of Nebraska, is important for supporting breeding programs aimed at providing safer crops for consumers. In the realm of reduction of the asparagine concentration in wheat-based …

Stable Engraftment Of Bifidobacterium Longum Ah1206 In The Human Gut Depends On Individualized Features Of The Resident Microbiome, María X. Maldonado-Gómez, Inés Martínez, Francesca Bottacini, Amy O’Callaghan, Marco Ventura, Douwe Van Sinderen, Benjamin Hillmann, Pajau Vangay, Dan Knights, Robert W. Hutkins, Jens Walter

Department of Food Science and Technology: Faculty Publications

Live bacteria (such as probiotics) have long been used to modulate gut microbiota and human physiology, but their colonization is mostly transient. Conceptual understanding of the ecological principles as they apply to exogenously introduced microbes in gut ecosystems is lacking. We find that, when orally administered to humans, Bifidobacterium longum AH1206 stably persists in the gut of 30% of individuals for at least 6 months without causing gastrointestinal symptoms or impacting the composition of the resident gut microbiota. AH1206 engraftment was associated with low abundance of resident B. longum and underrepresentation of specific carbohydrate utilization genes in the pre-treatment microbiome. …

Comparison Of Hermetic Storage Of Wheat With Traditional Storage Methods In India, Pavel Somavat, Haibo Huang, Sunil Kumar, Mukesh K. Garg, Mary-Grace C. Danao, Vijay Singh, Marvin R. Paulsen, Kent D. Rausch

Department of Food Science and Technology: Faculty Publications

India is among the countries experiencing high postharvest losses. Four hermetic bags, two metallic bins, and two gunny bag (also known as jute or burlap bag) piles each containing 1 tonne of wheat were instrumented with temperature, relative humidity, and carbon dioxide sensors. Representative samples from each structure were collected each month and tests for moisture, germination, insect-damaged grain, and milling yield were performed. After nine months, wheat stored in hermetic bags had higher germination (87%) and lower insect-damaged grain percentages (0% to 0.33% with a mean value of 0.2%). Hermetic bags with deliberately introduced Rhyzopertha dominica successfully eliminated the …

Fungi In The Healthy Human Gastrointestinal Tract, Heather E. Hallen-Adams, Mallory J. Suhr

Department of Food Science and Technology: Faculty Publications

Many species of fungi have been detected in the healthy human gut; however, nearly half of all taxa reported have only been found in one sample or one study. Fungi capable of growing in and colonizing the gut are limited to a small number of species, mostly Candida yeasts and yeasts in the family Dipodascaceae (Galactomyces, Geotrichum, Saprochaete). Malassezia and the filamentous fungus Cladosporium are potential colonizers; more work is needed to clarify their role. Other commonly-detected fungi come from the diet or environment but either cannot or do not colonize (Penicillium and Debaryomyces species, which are …

Matrix Effects On The Detection Of Milk And Peanut Residues By Enzyme-Linked Immunosorbent Assays (Elisa), Abigail S. Burrows

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

Food matrices are complex systems of lipids, carbohydrates, and proteins in which interactions between matrix components and allergenic proteins are known to have negative effects on the recovery of allergens when analyzed by ELISA. The purpose of this study was to first evaluate the recovery of milk and peanut residues from multiple food matrices and mixes and to secondly evaluate the use of a modified extraction protocol, sequential extractions, on the recovery of milk and peanut allergens.

Pastry dough matrices and pastry dough mixes incurred with milk were prepared at varying concentrations of flour and evaluated for recovery of NFDM. …

Effects Of Salt And Nitrite Concentration On The Shelf Life Of Deli-Style Ham, Regan Elise Stanley

Department of Animal Science: Dissertations, Theses, and Student Research

Deli-style hams were manufactured to measure the effects of salt and nitrite concentration on shelf life and physicochemical characteristics. Three replications of deli-style ham treatments were manufactured in a 3 x 4 factorial arrangement of salt concentration (0.7%, 1.4%, or 2.1%, meat block basis) and nitrite concentration and source (0 ppm, 100 ppm or 200 ppm sodium nitrite, SN, or 100 ppm sodium nitrite equivalent from pre-converted celery juice powder, CP; Veg Stable 506, Florida Food Products). Salt concentration, water activity, cook yield, and texture profile analysis (TPA) were measured on w 0. Color, pH, residual nitrite, and aerobic and …

From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza

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

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 …

Water And Energy Use Of Antimicrobial Interventions In A Mid-Size Beef Packing Plant, Rami M. M. Ziara, Shaobin Li, Bruce I. Dvorak, Jeyamkondan Subbiah

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Data regarding the water and energy usage of current antimicrobial interventions in beef packing plants is scarce. The objective of this study was to collect representative water and energy usage data in a beef packing plant, with emphasis on antimicrobial interventions, to provide baseline data for comparison of new intervention technologies developed by researchers. Permanent and portable water flow meters were installed on the plant’s plumbing system to collect water flow data from March 2014 to March 2015. A local utility company was hired to meter electricity at the different subsystems using portable data loggers. The natural gas used in …

Characterization Of Extraction Methods To Recover Phenolic-Rich Extracts From Black Beans (Phaseolus Vulgaris) That Inhibit Alpha-Amylase And Alpha-Glucosidase Using Response Surface Approaches, Mazen Alharbi

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Black beans contain high phenolic contents that are considered potent antioxidants. Relatively little is known about their ability to inhibit the carbohydrate-hydrolyzing enzymes α-amylase and α-glucosidase from releasing glucose from starch and/or disaccharides. The objective of this project was to determine the optimum procedures for extracting total phenols (TP), total flavonoids (TF) and total condensed tannins (TCT) from black beans (Phaseolus vulgaris), and then to determine the ability of the phenolic rich extracts to inhibit α-amylase and α-glucosidase. Due to their high phenolic levels, it was hypothesized that black beans would be an effective inhibitor of α-amylase and α-glucosidase, which …

Fecal Microbiome In Epidemiologic Studies [Letter], David A. Drew, Paul Lochhead, Galeb Abu-Ali, Andrew T. Chan, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

We congratulate Sinha and colleagues on their recent report comparing fecal sample collection methods for epidemiologic studies of the gut microbiome. These data contribute to the increasing body of literature describing robust methodological frameworks for specimen collection and processing. However, their claim that fixation of stool using RNAlater® results in “considerable changes to the microbiome diversity” contrasts with previous findings, including those from their earlier reports. We have previously demonstrated that self-collected stool stabilized with RNAlater® or other fixatives yields high fidelity and reproducibility in compositional profiling of DNA and RNA from shotgun sequence data, compared to immediately-frozen specimens. Additionally, …

Feasibility, Safety, Economic And Environmental Implications Of Whey-Recovered Water For Cleaning-In Place Systems: A Case Study On Water Conservation For The Dairy Industry, Yulie E. Meneses-GonzáLez

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

Several countries around the world are facing the challenge of producing food with limited water resources for a growing population. This reality is forcing all sectors involved in the food supply chain to look for water conservation strategies that contribute to assure global food security. Besides water consumption, the food industry has to deal with wastewater generation; therefore, water reconditioning and reuse is an attractive solution to address both issues. The goal of this research was to demonstrate that high quality water can be recovered from whey, a by-product of the cheese making process, and reused in cleaning-in place (CIP) …

Evaluation Of Qualitative Food Allergen Detection Methods And Cleaning Validation Approaches, Rachel C. Courtney

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

Allergen control plans are increasingly used by the food industry to prevent allergen cross-contact and validation of these plans involves methods to detect allergen protein residues. A commonly used rapid allergen detection method is lateral flow devices, although research about their validation is lacking. The objective of this research was to investigate lateral flow devices, their specificity and sensitivity to milk proteins and milk-derived ingredients, swabbing conditions, and applications in cleaning validation.

Several lateral flow devices advertised to detect total milk did not detect whey proteins or whey-derived ingredients. The overload level of the kits was highly variable (ranging from …

The Effect Of Salt Reduction On The Microbial Composition And Quality Characteristics Of Sliced Roast Beef And Turkey, Chad Gary Bower

Department of Animal Science: Dissertations, Theses, and Student Research

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 count. Bacterial communities were …

Synbiotic Ice Cream As A Probiotic Carrier Tested In A Human Blind Crossover Trial, Erin M. Mcnamara

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

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 …

Improving The Utilization Of Dry Edible Beans In A Ready-To-Eat Snack Product By Extrusion Cooking, Franklin Sumargo

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

The growing snacking habit and steady increasing demand for healthy snacks have drastically changed the ready-to-eat snack market in recent years. While the current healthy, ready-to-eat snack products are still dominated by whole cereal grains, legumes, especially dry edible beans, have a high potential to emerge in nutritional, novel food. Dry edible beans (Phaseolus Vulgaris L) are not only economically valuable but also nutritionally important, since they are important sources of proteins, B vitamins, mineral elements, and soluble dietary fibers even when compared to whole grain cereals. Recent studies have shown extrusion processing is not only effective at producing …

Reducing The Potential For Acrylamide Formation In Wheat Products, Amy Hauver, P. Stephen Baenziger, Mary J. Guttieri

UCARE: Research Products

Acrylamide, a chemical formed from free asparagine and reducing sugars during high-temperature cooking via the Maillard reaction (i.e. frying or baking) of high starch foods is deemed ‘probably carcinogenic to humans’ based on its affect in mice. In April of 2002, a group of Swedish researchers reported findings that presented evidence that heat-treated, starch-rich foods contained high levels of acrylamide, later linking the production of acrylamide to the Maillard reaction. A number of other studies have been done to link dietary intake of acrylamide to human cancers and other health effects, although many have had inconclusive results. Nevertheless, the World …

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 W. 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 …

Studies Of Debaryomyces Hansenii Killer Toxin And Its Effect On Pathogenic Bloodstream Candida Isolates, Rhaisa A. Crespo Ramírez

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

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 …

Characterization Of Extraction Methods To Recover Phenolic-Rich Extracts From Pinto Beans (Baja) That Inhibit Alpha-Amylase And Alpha-Glucosidase Using Response Surface Approaches, Mohammed Alrugaibah

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

Pinto beans contain high levels of diverse phenols, known mainly for their potent antioxidative properties. However, reports have shown that phenols can inhibit the carbohydrate–hydrolysis enzymes, alpha-amylase and alpha-glucosidase, thereby retarding glucose absorption. Still, a severe gap in knowledge exists on the ability of pinto beans to inhibit these enzymes. Therefore, the objective of this project was to determine the ability of phenolic rich extracts obtained from pinto beans (BaJa) to inhibit alpha-amylase and alpha-glucosidase. The hypothesis was that pinto beans would be able to inhibit these enzymes due to the presence of high levels of chemically diverse phenols. Response …

Prebiotics: Why Definitions Matter, Robert W. Hutkins, Janina A. Krumbeck, Laure B. Bindels, Patrice D. Cani, George C. Fahey, Yong Jun Goh, Bruce R. Hamaker, Eric C. Martens, David A. Mills, Robert A. Rastal, Elaine Vaughan, Mary Ellen Sanders

Department of Food Science and Technology: Faculty Publications

The prebiotic concept was introduced twenty years ago, and despite several revisions to the original definition, the scientific community has continued to debate what it means to be a prebiotic. How prebiotics are defined is important not only for the scientific community, but also for regulatory agencies, the food industry, consumers and healthcare professionals. Recent developments in community-wide sequencing and glycomics have revealed that more complex interactions occur between putative prebiotic substrates and the gut microbiota than previously considered. A consensus among scientists on the most appropriate definition of a prebiotic is necessary to enable continued use of the term.