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Presence, Co-Occurrence, And Daily Intake Estimates Of Aflatoxins And Fumonisins In Maize Consumed In Food-Insecure Regions Of Western Honduras, Luis Sabillón, Jackeline Alvarado, Alejandra Leiva, Rodrigo Mendoza, Raúl Espinal, John F. Leslie, Andreia Bianchini

Department of Food Science and Technology: Faculty Publications

Foodborne mycotoxins are a significant food safety risk in developing countries. Our objective was to determine the occurrence of and exposure levels to aflatoxins (AFs) and fumonisins (FBs) in maize intended for human and animal consumption in food-insecure regions of western Honduras. Total AFs and FBs were quantified with a monoclonal antibody-based affinity spectrofluorimetric method. FBs were detected in 614/631 samples of maize destined for human consumption at 0.3 to 41 mg/kg (mean, 2.7 mg/kg). Of the 614 positive samples, 147 had FB levels exceeding the U.S. Food and Drug Administration (FDA) advisory threshold of 4.0 mg/kg. AFs were detected …

Effect Of High-Pressure Processing On The Microbial Load And Functionality Of Sugar-Cookie Dough, Luis Sabillón, Jayne E. Stratton, Devin Rose, Kent M. Eskridge, Andreia Bianchini

Department of Food Science and Technology: Faculty Publications

Background and objectives: Refrigerated dough products have the potential to be a safety hazard to consumers because they could be consumed raw or undercooked. The objectives of this study were designed to evaluate the microbial and functionality changes in high pressured sugar-cookie dough as a function of a_w (0.80–0.87), pressure level (100–600 MPa), and holding time (1–6 min).

Findings: Endogenous microbial populations were marginally reduced (0.2–0.5 log CFU/g) by pressure treatments. However, treating the dough at 600 MPa for 6 min significantly reduced counts of inoculated Escherichia coli by as much as 2.0 log CFU/g. Increasing the a_{w …}

Heuristic And Hierarchical-Based Population Mining Of Salmonella Enterica Lineage I Pan-Genomes As A Platform To Enhance Food Safety, Joao Carlos Gomes-Neto, Natasha Pavlovikj, Carmen Cano, Baha Abdalhamid, Gabriel Asad Al-Ghalith, John Dustin Loy, Dan Knights, Peter C. Iwen, Byron D. Chaves, Andrew K. Benson

Department of Food Science and Technology: Faculty Publications

The recent incorporation of bacterial whole-genome sequencing (WGS) into Public Health laboratories has enhanced foodborne outbreak detection and source attribution. As a result, large volumes of publicly available datasets can be used to study the biology of foodborne pathogen populations at an unprecedented scale. To demonstrate the application of a heuristic and agnostic hierarchical population structure guided pan-genome enrichment analysis (PANGEA), we used populations of S. enterica lineage I to achieve two main objectives: (i) show how hierarchical population inquiry at different scales of resolution can enhance ecological and epidemiological inquiries; and (ii) identify population-specific inferable traits that could provide …

Fdst 403/803 – Food Quality Assurance, Byron D. Chaves

UNL Faculty Course Portfolios

Food Science and Technology (FDST) 403: Food Quality Assurance is an upper level required course for FDST undergraduate majors at the University of Nebraska-Lincoln. The course covers food safety regulations, food safety management systems, and statistical process control applied to food safety and quality in food manufacturing. This Peer Review of Teaching Portfolio documents the course analysis and reflection for spring 2021. Two mid-semester student course evaluations were performed on March 1 and April 5, the lecture immediately after the midterm exams. Anonymous paper and online surveys were filled out during class time asking students to reflect on the course …

Research Tools And Their Uses For Determining The Thermal Inactivation Kinetics Of Salmonella In Low-Moisture Foods, Soon Kiat Lau

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

The reputation of low-moisture foods as safe foods has been crumbling over the past decade due to repeated involvement in foodborne illness outbreaks. Although various pasteurization technologies exist, a majority are thermal processes and have not been well-characterized for pasteurizing low-moisture foods. In addition, the nature of a low-moisture food matrix introduces various experimental complications that are not encountered in high-moisture foods. In this dissertation, the development, building instructions, and characterization of various open source tools for studying the inactivation kinetics of microorganisms in low-moisture foods are described. The first tool is the TDT Sandwich, a dry heating device for …

Tdt Sandwich: An Open Source Dry Heat System For Characterizing The Thermal Resistance Of Microorganisms, Soon Kiat Lau, Jeyamkondan Subbiah

Department of Food Science and Technology: Faculty Publications

The determination of the thermal death kinetics of microorganisms has traditionally been performed with liquid baths which have some disadvantages such as liquid spillage and liquid infiltration into samples. The TDT Sandwich was developed as a free, open source alternative that utilizes dry heat. The system is capable of heating samples up to 140C and maintaining it within 0.2C of the target temperature. Other features of the TDT Sandwich include adjustable heating rates up to approximately 100C/min, real-time display and recording of temperature readings at a nominal rate of 5 Hz, an optional thermocouple for acquiring temperature of samples, built-in …

Mind The Gaps: How Can Food Safety Gaps Be Addressed In Developing Nations?, Jessie L. Vipham, Byron D. Chaves, Valentina Trinetta

Department of Food Science and Technology: Faculty Publications

As global food systems integrate, to meet the demands of a growing global population, safe and healthy agriculture value-chains will be essential to maintaining public health worldwide. In many ways, the current global food production landscape is made up of “mice and men.” Meaning that the food sector within and across most countries includes both large-scale corporate agriculture production and varying degrees of small-scale agriculture production; the variation being the interpretation of small scale, which is highly dependent upon the country. This structure presents challenges for the creation of effective food safety systems in many countries, and can contribute to …

Chapter 8 Keeping Wildlife Out Of Your Food: Mitigation And Control Strategies To Reduce The Transmission Risk Of Food-Borne Pathogens, Alan B. Franklin, Kurt C. Vercauteren

USDA Wildlife Services: Staff Publications

In this chapter, we provide a general framework for developing strategies to mitigate the contamination of agricultural operations with pathogens carried by wildlife. As part of this framework, we present adaptive management as a viable approach to developing these strategies to reduce the uncertainty over time as to whether management methods are being effective. We provide the general steps to developing an adaptive management strategies as well as generic mitigation methods that can be applied to agricultural operations as part of an adaptive management strategy.

Food Safety Knowledge, Attitudes, And Behaviors Of Native American Families With Young Children: A Mixed Methods Study, Kara Vlasin-Marty, Paula Ritter-Gooder, Julie A. Albrecht

Department of Nutrition and Health Sciences: Faculty Publications

Children are at increased risk for foodborne illness due to underdeveloped immune system. Limited research has been reported on food safety knowledge of Native American families with children 10 years of age and younger. This study was conducted to determine the food safety knowledge, attitudes, and behaviors of the main food preparer in these families by collecting quantitative and qualitative data simultaneously in a mixed method approach. A food safety knowledge survey created using FightBAC!™ concepts was administered prior to focus groups discussions held in Native American communities using a script based upon the Health Belief Model. Quantitative data were …

Biosafety: Evaluation And Regulation Of Genetically Modified (Gm) Crops In The United States, Richard E. Goodman

Department of Food Science and Technology: Faculty Publications

This review of the safety assessment of genetically modified (GM) crops is focused primarily on the process and progress in the United States (US). It reviews the development of the safety evaluation process from the Asilomar conference in 1975 considering issues relevant to recombinant DNA technology, to discussions between the US government, academic and industrial scientists between 1984 and 1994 when the first GM crops were being field tested and evaluated commercial release for food and feed production. International guidelines were also reviewed for consistency with the US system. The overall process includes consideration of information relating to history of …

National Animal Health Monitoring Survey For Toxoplasma Gondii And Trichinella Spiralis – Npb #12-121, Dolores Hill

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The United States Department of Agriculture (USDA) initiated the National Animal Health Monitoring System (NAHMS) in 1983 to collect, analyze, and disseminate data on animal health, management, and productivity in U.S. domestic livestock populations. The purpose of this study was to determine the national seroprevalence of Toxoplasma gondii and Trichinella spiralis in grower/finisher pigs using sera collected during the 5th National Swine Study (NAHMS Swine 2012). Sera was collected during the voluntary survey of 202 grower/finisher swine production sites located in 13 states accounting for ~90% of U.S. swine production (Iowa, Illinois, Indiana, Kansas, Minnesota, Missouri, Nebraska, North Carolina, Ohio, …

Food Safety Education Cube For Native Americans, Kelsey Crews Bair, Rachel C. Sinley, Julie A. Albrecht

RURALS: Review of Undergraduate Research in Agricultural and Life Sciences

Foodborne illnesses impact millions of individuals each year, with young children at high risk of contracting such diseases. Many of these pathogens responsible for these illnesses can be destroyed with proper food handling techniques. Research has shown there is a need for improved food safety education among the general public. This project sought to increase food safety knowledge by developing a food safety educational tool that expands on current meat handling information. A “Food Safety Cube” was developed that expands on the current Food Safety and Inspection Service (FSIS) “Safe Handling Instructions” label. This tool was positioned throughout several high …

Disentangling Demand-Enhancing And Trade-Cost Effects Of Maximum Residue Regulations, Bo Xiong, John Beghin

Department of Agricultural Economics: Faculty Publications

Maximum residue levels (MRLs) regulations in plant products can create unnecessary trade barriers on one hand and enhance demand via risk mitigation or quality assurance on the other. We stipulate a generalized gravity equation model to disentangle the effects of MRLs on the import demand and foreign exporters’ supply. Applying the framework to the MRLs on pesticides imposed by high-income OECD countries, we find that the MRLs jointly enhance the import demand and hinder foreign exporters’ supply. In addition, exporters from the less and least developed countries are more constrained by the MRLs than their competitors from the developed world.

Food Safety Of Native American Families With Young Children In Nebraska: A Mixed Methods Study, Kara A. Vlasin-Marty

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Food safety knowledge, attitudes, and behaviors of Native American families with young children were studied using a mixed methods approach. Quantitative and qualitative data was collected together, analyzed separately, and compared. A food safety knowledge survey was created using the FightBac!™ concepts. A total of 102 participants completed the knowledge survey during survey validation and as part of focus groups. Focus groups were conducted using a script based on the Health Belief Model to better understand the food safety beliefs and practices of Native Americans. Eight focus groups were conducted in Lincoln, Macy, Omaha, South Sioux City, Walthill (2), and …

A Mixed Methods Approach To Food Safety Knowledge, Beliefs And Practices In Hispanic Families With Young Children In Nebraska, Kristen M. Stenger

College of Education and Human Sciences: Dissertations, Theses, and Student Research

This mixed methods study addresses food safety for Hispanic families with young children in Nebraska. A convergent mixed methods design was used, where qualitative and quantitative data were collected in parallel, analyzed separately and then merged in analysis and interpretation. A quantitative food safety knowledge survey (n=90, 52 from focus groups, 38 from piloting the survey), was used to assess the FightBac!™ concepts: Clean, Separate, Cook, Chill, and two additional concepts: foods that increase risk, and groups at increased risk. Qualitative focus groups explored food safety handling beliefs and practices through the lens of the Health Belief Model. Focus groups …

Misting Effects Of The Microbial Quality Of Retail Leaf Lettuce, Rachel Rossman, David Giraud, Julie A. Albrecht

RURALS: Review of Undergraduate Research in Agricultural and Life Sciences

Limited research has been done on the microbial quality of produce that has been misted at retail food settings. Therefore, our objective was to determine the microbial quality of leaf lettuce displayed at retail in misted or non-misted displays. Three grocery stores that mist and three grocery stores that do not mist lettuce were selected to obtain leaf lettuce. Leaf lettuce was analyzed for aerobic plate count (APC), yeast, mold, and Enterobacteriaceae. APC ranged from 6.23 to 6.36 Log10/g for misted leaf lettuce compared to 5.20 Log10/g for non-misted leaf lettuce. Yeast counts ranged from 4.34 to 4.91Log10g for misted …

Strategic Discussions For Nebraska: Opportunities For Nebraska -- Food Scarcity, Mary Garbacz

Department of Agricultural Leadership, Education, and Communication: Faculty Publications

Strategic Discussions for Nebraska is a program in the University of Nebraska-Lincoln Institute of Agriculture and Natural Resources that produces an annual publication called Opportunities for Nebraska, focusing on a different topic each year. The publication is produced in hard copy and also is available online at www.sdn.unl.edu.

The content for each publication is produced by UNL students enrolled in a Magazine Writing course each spring semester, taught by the SDN coordinator. Students conduct interviews with UNL researchers and write stories for inclusion in the publication. The interviews are captured on video and are edited into video montages, …

A 3-D Computational Fluid Dynamics Model For Forced Air Cooling Of Eggs Placed In Trays, Vikas Kumar, Ai Pheeng Wee, Sohan Birla, Jeyamkondan Subbiah, Harshanardhan Thippareddi

Department of Biological Systems Engineering: Papers and Publications

Shell eggs must be cooled quickly after laying for controlling Salmonella Enteritidis (SE) growth. To fulfill a research need identified by Food Safety and Inspection Service (FSIS), a 3-D Computational Fluid Dynamics (CFD) model was developed to predict the temperature of eggs placed on a tray (6 rows × 5 columns) under forced air cooling. The continuity, momentum, and energy equations were solved along with standard k-ε turbulence model using PHOENICS software. The model was validated by conducting experiments in a wind tunnel at various air temperatures (7–11 °C) and velocities (0.3– 0.7 m/s). Root mean square error for predicting …

Suggested Improvements For The Allergenicity Assessment Of Genetically Modified Plants Used In Foods, Richard E. Goodman

Department of Food Science and Technology: Faculty Publications

Genetically modified (GM) plants are increasingly used for food production and industrial applications. As the global population has surpassed 7 billion and per capita consumption rises, food production is challenged by loss of arable land, changing weather patterns, and evolving plant pests and disease. Previous gains in quantity and quality relied on natural or artificial breeding, random mutagenesis, increased pesticide and fertilizer use, and improved farming techniques, all without a formal safety evaluation. However, the direct introduction of novel genes raised questions regarding safety that are being addressed by an evaluation process that considers potential increases in the allergenicity, toxicity, …

Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez

Department of Biological Systems Engineering: Dissertations and Theses

The meat industry is required to comply with processing performance standards for preventing the growth of foodborne pathogens in products. These performance standards, established by the United States Department of Agriculture - Food Safety and Inspection Service (USDA-FSIS) require a reduction of Salmonella spp (lethality standard) and limit the growth of sporeforming bacteria (stabilization standard) in certain processed meat products. In general, strategies used to comply with these standards are associated with thermal processing. Meat processors have difficulties complying with these performance standards. Moreover, thermal processing deviations are an issue in the meat industry that generate uncertainty regarding the safety …

Food Handling Practices, Knowledge And Beliefs Of Families With Young Children Based On The Health Belief Model, Adeline Lum

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

Objective: To determine current food handling practices, knowledge and beliefs of primary food handlers with children 10 years old and the relationship between these components.

Design: Surveys were developed based on FightBac!™ concepts and the Health Belief Model (HBM) construct.

Participants: The majority of participants (n= 503) were females (67%), Caucasians (80%), aged between 30 to 49 years old (83%), had one or two children (83%), prepared meals all or most of the time (76%) and consumed meals away from home three times or less per week (66%).

Analysis: Descriptive statistics and inferential statistics using Spearman’s rank correlation coefficient (rho) …

Heating Performance Assessment Of Domestic Microwave Ovens, Krishnamoorthy Pitchai, Sohan Birla, Jeyamkondan Subbiah, David D. Jones

Department of Biological Systems Engineering: Conference Presentations and White Papers

Due to inherent nature of standing wave patterns of microwaves inside a cavity and dielectric properties of different components in a food, microwave heating leaves non-uniform distribution of energy inside the food volumetrically. Achieving heating uniformity plays critical role in improving the safety of microwave heated products. In this paper, we present a method for assessing heating uniformity within domestic microwave ovens. A custom designed container
was used to assess heating uniformity of a range of microwave ovens using IR camera. The study suggested that the best place to place food in a microwave oven is not at center but …

Comparison Of Meat Composition From Offspring Of Cloned And Conventionally Produced Boars, S. C. Walker, R. K. Christenson, R. P. Ruiz, D. E. Reeves, S. L. Pratt, F. Arenivas, N. E. Williams, B. L. Bruner, I. A. Polejaeva

Roman L. Hruska U.S. Meat Animal Research Center: Reports

This study compares the meat composition of the offspring from boars produced by somatic cell nuclear transfer (n = 4) to that of the offspring from conventionally produced boars (n = 3). In total, 89 commercial gilts were artificially inseminated and 61 progressed to term and farrowed. All of the resulting piglets were housed and raised identically under standard commercial settings and slaughtered upon reaching market weight. Loin samples were taken from each slaughtered animal and shipped offsite for meat composition analysis. In total, loin samples from 404 animals (242 from offspring of clones and 162 from controls) …

A Mathematical Model For The Validation Of Safe Air-Blast Chilling Of Cooked Hams, L. J. Wang, A Amézquita, Curtis L. Weller

Department of Biological Systems Engineering: Papers and Publications

An integrated mathematical model of heat transfer and temperature-dependent bacterial growth was developed to validate the safety of cooked hams during air-blast chilling. Heat transfer through a cooked ham was mathematically modeled and analyzed with a finite element method. Response of bacteria to temperatures was quantitatively described using predictive microbiology. The cumulative effect of temperature history on the bacterial growth was taken into account in the model. For chilling cooked hams from 71°C to 10°C, the maximum error between the predicted and experimental core temperature was within 2.2°C, and the deviation between the predicted and measured total weight losses was …

Regulation Of Enteric Endophytic Bacterial Colonization By Plant Defenses, A. Leonardo Iniguez, Yuemei Dong, Heather D. Carter, Brian M. M. Ahmer, Julie M. Stone, Eric W. Triplett

Department of Biochemistry: Faculty Publications

Bacterial endophytes reside within the interior of plants without causing disease or forming symbiotic structures. Some endophytes, such as Klebsiella pneumoniae 342 (Kp342), enhance plant growth and nutrition. Others, such as Salmonella enterica serovar Typhimurium (S. typhimurium), are human pathogens that contaminate raw produce. Several lines of evidence are presented here to support the hypothesis that plant defense response pathways regulate colonization by endophytic bacteria. An ethyleneinsensitive mutant of Medicago truncatula is hypercolonized by Kp342 compared to the parent genotype. Addition of ethylene, a signal molecule for induced systemic resistance in plants, decreased endophytic colonization in Medicago spp. …

Finite Element Modeling And Experimental Validation Of Cooling Rates Of Large Ready-To-Eat Meat Products In Small Meat-Processing Facilities, A. Amézquita, L. Wang, Curtis L. Weller

Department of Biological Systems Engineering: Papers and Publications

A two−dimensional axisymmetric transient heat conduction model was developed to simulate air chilling of large ready−to−eat meat products of ellipsoidal shape. A finite element scheme, using 1,600 linear triangular elements with 861 nodes, was implemented in Matlab 6.5 to solve the model. The model considered a variable initial temperature distribution and combined convective, radiative, and evaporative boundary conditions. Predicted values agreed well with experimental data collected in actual processing conditions. Validation of model performance resulted in maximum deviations of 2.54°C and 0.29% for temperature and weight loss histories, respectively. The maximum temperature deviation (2.54°C) occurred at the surface; however, for …

G05-1573 Meat And Fabrication-Room Temperatures For Food Safety, Alejandro Amezquita, L. Wang, Harshavardhan Thippareddi, Dennis E. Burson, Curtis Weller

University of Nebraska-Lincoln Extension: Historical Materials

Within the last 20 years, several meat-borne pathogenic microorganisms have emerged in the United States, causing numerous outbreaks of disease and death, as well as drastic economical losses.

Guidelines in this NebGuide are suggested for controlling temperature of meat and meat products in fabrication rooms so as to prevent detrimental growth of meat-borne pathogens.

Nf04-604 Barbecue Food Safety, Julie A. Albrecht

University of Nebraska-Lincoln Extension: Historical Materials

Cooking outdoors was once only a summer activity shared with family and friends. Now more than half of Americans say they are cooking outdoors year round. So, whether the snow is blowing or the sun is shining brightly, it's imporant fo follow food safety guidelines to prevent harmful bacteria from multiplying and causing foodborne illness. Use these simple guidelines for grilling food safely.

G03-1520 Current Issues Affecting Youth Swine Shows, Rosie Nold

University of Nebraska-Lincoln Extension: Historical Materials

The original purpose of youth livestock shows was two-fold: 1) to provide an educational experience where young people could learn animal management practices, as well as personal/character development; and 2) to recognize the best animals in the industry.

This NebGuide addresses practices which have developed to enhance the appearance of a pig that is to be exhibited, but which may be detrimental to the commercial pork industry.

Ec98-454 Nutrition For The Older Adult, Wanda Koszewski, Carol Ray, Amy Sutton, Lisa Beretta

University of Nebraska-Lincoln Extension: Historical Materials

Nutrition is important for everyone at any age and is one of the keys to healthy living. We are all overwhelmed with new information about nutrition each day. This publication focuses on nutrition topics specifically related to the elderly.