Browsing by Subject "College of Food, Agricultural and Natural Resource Sciences"

Now showing 1 - 20 of 61

Adding Value to Ethanol Production Byproducts Through Production of Biochar and Bio-oil
(2011-11) Spokas, K.; Ruan, R.; Morrison, R.
This study aims at increasing the value of distillers’ grain by sequestering carbon and producing additional renewable energy resources (bio-oil and syngas) through microwave assisted pyrolysis. Bio-oil can be further upgraded to drop-in transportation fuels. Biochars are tested for their potential as soil improvement agents.
Associating Lameness in Swine with the Presence of Mycoplasma Hyosynoviae and Mycoplasma Hyorhinis in Oral Fluids
(2019) Thurston, Joseph;
Mycoplasma hyorhinis and M. hyosynoviae have both been associated with causing lameness in growing pigs. The most common method of detecting these bacteria is through sampling oral fluids via cotton rope. The oral fluids can be subjected to real-time Polymerase Chain Reaction (PCR) to determine both the genetic material of the bacteria and provide a potential measure of the bacterial load. This study tested the oral fluids of 17 farms across Iowa, South Dakota, Wisconsin, and Nebraska. Mycoplasma hyorhinis was detected on 94.14% of the farms, while 52.94% of farms were positive for M. hyosynoviae. The pigs were also scored on a scale of 0 - 4 for lameness. The lameness scores were compared to the Ct values returned from the real-time PCR. Mycoplasma hyosynoviae was shown to be significantly (p<0.05) associated with lameness in pigs, while M. hyorhinis was not (p=.274). The relationship of age of pigs and Ct values of M. hyosynoviae, and therefore lameness, was also evaluated. Data supported older pigs being more at risk to develop M. hyosynoviae-associated lameness. This impacts the diagnosis process of producers and veterinarians, as M. hyorhinis should not be included in the tests run on oral fluids of lame pigs.
Bark Beetle: Fungus Interactions in Declining Hickory Trees
(2010-11-29) Zenner, Bobbi
The objective of this study is to determine whether C. smalleyi is commonly carried by hickory bark beetles when they emerge from beetle infested, declining bitternut hickory in late spring. The findings will help answer the question of whether the beetle is an important vector of C. smalleyi. These results will be added to those of additional assays of beetles from the same site as well as from a second Wisconsin location.
Biobased Pressure-Sensitive Adhesives
(2010) Roerdink Lander, Monique; Zhang, Jiguang; Houtman, Carl J.; Severtson, Steven J.
Pressure sensitive adhesive (PSA) products have become ubiquitous in our homes and offices through address labels, stamps, sticky notes, and tapes. The majority of these PSAs are based on petroleum-derived acrylates. In 2006, more than 300 million dry pounds of acrylic adhesive was sold in the United States. Incorporation of biomass-derived resources as a substitute for acrylates will make a significant contribution in the development of sustainable products. We developed PSAs with high biomass-content using biomass-based macromonomers, which can copolymerize with standard adhesive acrylates and replace 40-60% of petroleum-based raw materials. The work described here is an example of a novel, yet pragmatic approach to develop sustainable PSA formulations by simple modifications of successful commercial products, while maintaining performance.
Biogeochemical patterns and processes in buoyant, deep-sea hydrothermal plumes
(2011-08-11) Wendt, Kathleen
Along the global mid-ocean ridge, sub-seafloor hydrothermal circulation results in the exchange of heat and chemical species between seawater and the ocean crust. The resulting thermally and geochemically altered fluids are vented at the seafloor. The mixing of cold, oxic deep-ocean waters with hydrothermal fluids creates plumes with physically and chemically dynamic features. Hydrothermal plumes represent a globally distributed interface where marine hydrothermal circulation exerts its biogeochemical influence on elemental budgets of ocean basins. The goal of the present study is to describe the microbiological niches created by physical and geochemical gradients in plumes. One of our central hypotheses is that microorganisms respond to and alter the geochemistry of hydrothermal plumes. To achieve this goal and test our hypothesis, a field study was undertaken at the Eastern Lau Spreading Center (ELSC). While multiple vent sites along the ELSC are included in the larger study, here we report on an integrated, biogeochemical investigation of a single buoyant plume within ABE vent field. A series of replicate sample sets were collected by in situ filtration at 0.5m, 40m, 200m within a buoyant plume using the ROV JASON. Above plume background and near bottom background sample sets were also collected. Hydrothermal plume particles in sample replicates or splits have been queried for bulk geochemistry, particle-by-particle mineralogy, and microbial community composition. These three data streams are being evaluated individually to characterize the geochemical and microbiological changes throughout the plume with respect to above and below plume backgrounds. In addition, an iterative and integrated analysis is being used to compare: (1) calculated mineralogy to direct measurements; and (2) predicted energy yields from chemoautotrophy to observed microbial composition.
Connecting to the Cold-blooded: Impacts of Educational Messaging on Audience Attitudes Towards Rattlesnakes
(2022) Bachhuber, Owen;
As some of the most feared and misunderstood animals in North America, rattlesnakes are threatened by human persecution. Zoos, wildlife managers, and other conservation organizations seek to increase public acceptance of rattlesnakes through educational programming. This thesis addresses two key questions: 1) What is the effect of a rattlesnake exhibit on the attitudes of zoo guests, and 2) What is the effect of social complexity messaging on student attitudes towards rattlesnakes. I formulated a survey to quantify attitudes towards rattlesnakes using a seven-point Likert scale and administered it to visitors before and after walking through the Desert Dome of Omaha’s Henry Doorly Zoo and Aquarium. The same survey was given to zoology students at the University of Minnesota before and after learning about rattlesnake social complexity during a reptile diversity lab. I measured the impacts of the two learning environments using a two-tailed t-test to compare the incoming and outgoing attitudes of participants. No statistically significant changes in attitudes towards rattlesnakes were detected in guests after viewing the Desert Dome exhibits. Zoology students reported a significantly more positive view towards rattlesnakes after learning about rattlesnake social complexity, including increased utilitarian and ecologistic attitudes. Whereas public education programs have historically cited the ecological and biomedical contributions of rattlesnakes, this study suggests that the emerging field of reptile sociality has the potential to humanize rattlesnakes and increase audience acceptance of them.
Creation of Near-Isogenic Wheat Lines for Use in Validating the Effect of a Novel Source of Fusarium Head Blight Resistance
(2010-04-21) Nelson, Matt
Fusarium Head Blight, also known as scab, is the most serious disease affecting wheat production in the upper Midwest. Scab is caused by the fungus Fusarium graminearum. Scab is the major reason for the dramatic loss of wheat production in the 1990’s and is still a major problem today. Therefore, identifying a novel source of genetic resistance in wheat is very important. Dr. James Anderson’s lab identified a quantitative trait locus (QTL) region on the long arm of chromosome 3B that appears to be conferring resistance to scab. The purpose of this research is to create near-isogenic wheat lines (NILs) to validate and quantify the effect of the QTL on Fusarium Head Blight infection.
Designing a Screening Method for Organic Seed Treatments
(2009-04-08) Lis, Dmitriy
Certified organic crop producers have limited options available for controlling seed related diseases. I have developed a screen that could be utilized to test various plant extracts as a possible seed treatment. In the initial screen, I tested paper birch (Betula papyrifer) and staghorn sumac (Rhus typhina) extracts against 4 plant pathogens: Fusarium solani, Phytophthora sojae, Rhizoctonia solani, and Pythium spp. The highest concentration of the sumac extract (25.0 micrograms/ml) reduced the growth of R. solani by 67%, F. solani and Pythium spp. by 100%, and P. sojae by 80%. The highest concentration of the sumac extract (25.0 micrograms/ml) reduced the growth of F. solani and Pythium spp. equal to or greater than the commercial seed treatment fungicides. The highest concentration of the paper birch extract (25.0 micrograms/ml) reduced the growth of R. solani by 47%, Pythium spp. by 40%, and P. sojae by 40%. Neither the sumac or the paper birch extract reduced the germination of soybean seeds.
Determining the Effectiveness of Cryotherapy to Eliminate Plant Virus in Potato
(2010-06-08) Schneider, Hannah M.
Potatoes are vegetatively propagated which allows for the passage of viral diseases from one generation to the next, making it possible for entire clonal populations to become infected with the same pathogen. This makes virus eradication an extremely valuable management tool in potato production. It has recently been acknowledged that cryotherapy is an effective method for removing viruses from plant shoot tips. Specifically, cryotherapy involves the excision of shoot tips which are frozen in liquid nitrogen, then cultured in a sterile environment until cells regenerate into plants. This study used ELISA testing to document existing viruses in potato varieties MN02696, MN18747, MN99460-14, COMN04788-04, COMN04788-09, and COMN04692-11 and subjected plant material to two different cryotherapy methods; treatment one (encapsulation method) and treatment two (vitrification method). Treatment one involved three replications; replication two decreased the length of the liquid nitrogen exposure and replication three double coated the beads with a sodium alginate solution. Plant material did not survive in any replications of treatment one, however, plant survival was noted in treatment two. Three weeks after treatment two, plant material was evaluated for survivability. Varieties COMN0477-04, MN 18747, and MN 99460-14 appeared to have the highest levels of survival. Some varieties, MN 02696, COMN 04692-11, MN 18747, and COMN 04788-09 had even developed new shoots. In completing this study, the data collected helped determine which methods allow for the greatest survivability and therefore virus eradication in potato.
Development of a Solar Smoleniec/Stirling Hybrid Thermo-Mechanical Generator
(2010) Goldberg, Louise F.
The Thermo-Mechanical Generator was invented in 1967 and is an ingeniously simple and elegant heat engine operating on a Stirling thermodynamic cycle that can yield cogenerated electrical and thermal energy from moderately hot heat sources (200-500°C). A new version of this heat engine has been invented that is capable of operating off concentrated solar energy provided by inexpensive, acrylic Fresnel lenses. A key innovation in the technology is the use of a digital thermodynamic Smoleniec/Stirling cycle to optimize the performance of the heat engine in real time. A state space analysis of the engine has been completed that demonstrates that the invention can operate successfully. So far, the analysis has predicted an output electrical power of 1.9 kW when operating between hot and cold temperature limits of 500 C and 20 C respectively. Under these conditions the engine operates at a frequency of 87 Hz.
Effect of protein type on the loss of flavor compounds in protein bars
(2017) Sia, Xin Rong;
A problem with high-protein foods is that flavor compounds added are “lost” and no longer perceptible by the consumers over time, due to the flavor compounds undergoing various binding interactions with the protein. Knowing which flavors interact more extensively with which proteins can help manufacturers decide if a certain flavor should be added in excess in order for the flavor to still be perceptible by the time consumers consume it. Gaining an understanding of which proteins work as a better carrier for which flavor compounds allows for better formulations that holds up well over time without degradation in sensory quality. The aim of the project was to investigate the effects of using different types of protein isolate (whey, soy, rice and pea) on the rate of loss of nine different flavors compounds (allyl sulfide, isoamyl acetate, furfuryl mercaptan, benzaldehyde, methyl salicylate, menthol, D-carvone, γ- nonalactone and trans-α-ionone) in a protein bar matrix system. The nine flavor compounds were added a protein bar model system and stored at 45°C over four weeks for an accelerated shelf-life study. Samples were taken at 0, 1, 2 and 4 week s of storage time. Flavor compounds were extracted from each sample by Stir Bar Sorptive Extraction and thermally desorbed in the injection port of a gas chromatography. The amount of detectable flavor compounds (assumed to not be bound to the protein) was determined semiquantitatively using the peak areas of each flavor compound on the chromatogram and corrected with an internal standard. The percentage loss of each flavor compound was then calculated at each time point, with Week 0 as a baseline of 100%. Soy protein showed the least binding with flavor compounds initially, especially with compounds of lower molecular weight. However, soy protein had a very high rate of reactions with flavor compounds over one month of storage. Rice protein the slowest rate of binding interactions with flavor compounds, and was the most unreactive with low molecular weights flavor compounds such as allyl sulfide, isoamyl acetate and benzaldehyde. Pea and whey protein were both rather reactive with flavor compounds, but pea protein showed better performance with flavor compounds of higher molecular weights. Unlike whey and soy protein, rice and pea protein are not as commonly used in food products due to their lack of functionality. However, as a flavor carrier, rice protein shows much potential due to its lack of interaction with flavor compounds. In addition, the emerging trend of plant proteins might increase consumer demand and make these proteins more cost-effective to produce too.
The Effect of Root Architecture on Phosphorus Uptake in Alfalfa (Medicago sativa)
(2012-04-18) Slotke, Andrea
Nutrient uptake is a multifaceted system which is not fully understood. Many components, such as plant species, root structure, cultivar, nutrient application, nutrient movement within the soil, and mycorrhizal activity all play a part. While it is generally accepted that these mechanisms each play a part, the actual affect of each is not fully known. This study compared phosphorus uptake and plant yield in alfalfa Medicago sativa under varying conditions, including: high or low root system branches; alfalfa or alfalfa/grass mixtures; and with and without added phosphorus (P) on low P-testing soil. This experiment indicates a positive correlation between P uptake and yield with added P, as well as an interaction of root structure with P supply. This interaction indicates that under low P conditions P uptake did not differ significantly in the pure alfalfa stand, while in the alfalfa/grass mixture the high branching root systems show greater P uptake. Further research is examining the mycorrhizal component of uptake and yield through an analysis of nucleotide differentiation of fungi present on the roots. These results will be compared with plant P concentration, P uptake, and yield to evaluate the correlation between P acquisition and mycorrhizal abundance and diversity.
The Effect of Saturated Fatty Acids on Lipogenic Gene Expression in Rat Primary Hepatocytes
(2009-04-08) Best, Amanda
Consumption of saturated fat has been associated with the development of obesity, diabetes, hepatic steatosis and related diseases. Additionally, animal studies have shown that consumption of a diet high in saturated fat results in a rapid upregulation of hepatic lipogenic genes. Thus, to determine if saturated fatty acids have a direct effect on hepatic gene expression, rat primary hepatocytes were cultured and treated with various fatty acids. RNA was harvested from the hepatocytes and cDNA was subsequently prepared to analyze for lipogenic gene expression. Lipogenic enzymes included fatty acid synthase (FAS), acetyl-coA carboxylase (ACC) isoforms alpha and beta, stearoyl-coenzyme A desaturase 1 (SCD1) and fatty acid elongase 6 (Elovl6). Although lipogenic gene expression was altered in response to the presence of insulin and glucose, saturated fatty acids did not appear to significantly upregulate gene expression of lipogenic genes. These data suggest that the effects of saturated fatty acids on lipogenic gene expression in the liver are not direct. Further experiments will explore whether signals from the adipose tissue or inflammatory signals from microphages are necessary for saturated fatty acids to cause changes in de novo lipogenesis.
Effect of the Addition of Clay and Wetting/Drying Cycles to the Contaminated Soils at the National Crude Oil Spill Fate and Natural Attenuation Research Site (NCOSFNARS)
(2012-04-18) Wendt, Bryan
Although thirty-three years have passed since the 1979 pipeline break at the NCOSFNARS near Bemidji, Minnesota the soil within the zone sprayed by pipeline oil exhibits strong signs of oil contamination. The soils found within the spray zone are water repellent due to this contamination, and in result affects the growth of non-woody and woody vegetation. In the pursuit of providing alleviation techniques for oil-contaminated soils, a study has been initiated to evaluate the effectiveness of clay addition to alleviate soil hydrophobicity. This will be done by first conducting particle size distributions of the soil. Secondly, clay will be added at various rates and water repellency will be tested for using the molarity of ethanol (MED) test and water drop penetration time (WDPT) test. Lastly, wetting/drying cycles will be imposed on the sample and retested for water repellency.
Effectiveness of Vehicle-towed Nest Drags at Finding Duck Nests
(2011-04-13) Nosal, Amanda
Effective wildlife management depends on the assumption that the research techniques employed are scientifically and ecologically sound. In the management of popular waterfowl species, like dabbling ducks, nest density and success are often assessed using a vehicle-towed nest drag. This technique involves systematically searching a treeless, herbaceous habitat using two vehicles such as jeeps or ATVs with a heavy cable and chain, or just a chain, stretched between them. The nest drag passes over the vegetation where ducks nest, causing females to flush from the disturbance. Their nests can then be marked and revisited to collect data on nesting densities and reproductive success, and consequently used to devise appropriate management schemes. By analyzing data collected in habitats owned by Ducks Unlimited Canada, I evaluated the effectiveness of vehicle-towed nest drags at finding duck nests using the specialized population estimation software program DISTANCE. Specifically, I tested if nest detection was influenced by the distance from the towing vehicles, nest age, and duck species. My research provides “correction factors” that allow investigators to estimate the proportion of nests that are missed during regular surveys for waterfowl nests.
Effects of DEET on Proteins in Mosquito Cells
(2009-04-08) Hellestad, Vanessa
DEET, N,N-Diethyl-meta-toluamide is the most common active ingredient in insect repellents. It is a chemical applied to the skin or clothing that is used to protect against arthropods such as ticks and mosquitoes. We did preliminary experiments that showed the surprising result that DEET kills mosquito cells in tissue culture. This was unexpected because cultured cells do not have sensory organs to detect a repellent. While running SDS gels we discovered a protein that was expressed in cells that were treated with DEET and absent in those that were not.
The Effects of Different End Anchors on Satiety Scales
(2009-04-08) Long, Alexis
Two scales that measure hunger and fullness were compared in this study, the Satiety Labeled Intensity Magnitude (SLIM) scale and the General Labeled Magnitude Scale (GLMS). The scales differed in terms used to define satiety and their end points. The research looked at which scale was more effective and the effect of varying end anchors. To determine which scale was best, 40 volunteers came in three times and ate three snacks differing in caloric value. Each volunteer rated their hunger and fullness before and after each snack. Twenty volunteers used the SLIM scale and the other twenty used the GLMS. Analysis shows one scale was not superior to another, but the end anchors did affect how hunger and fullness were rated. The GLMS gave much more condensed data, and overall fullness was more affected than hunger.
Effects of Pasteurization Method on Lactose
(2012-04-18) Daninger, Erin
In response to claims that lactose-intolerant people were able to drink milk pasteurized utilizing the low temperature, long time method, it was decided to conduct a study comparing the lactose levels in milk pasteurized with two different methods: low temperature, long time (145 degrees F for 30 minutes) and high temperature, short time (165 degrees F for 15 seconds). It was hypothesized that there would be higher available lactose levels in the milk pasteurized with high temperature, short time method. Milk from Autumnwood Farm, a local creamery that pasteurizes with the low temperature, long time method, was used. Raw milk was also collected at the same time and pasteurized in small batches at the high temperature, short time method requirements. Milk samples were analyzed with a colorimeter to determine if browning was evident. After sample clean up and Megazyme Lactose and D-Galactose kit preparation, the lactose and D-galactose levels were determined with a spectrometer. Samples were prepared and run through high-performance liquid chromatography. First round results showed minimal differences with the colorimeter; varying largely based on homogenization rather than pasteurization. Spectrometer and HPLC results did not show differences in lactose concentrations in the various samples. Further research will be conducted to see if there are differences in milk protein, to see if the Maillard reaction has changes on the lactose.
The Effects of Satiety and Hunger on Normal, Overweight, and Obese BMI Ranges
(2010-05-06) Olson, Paula
The purpose of this project was to determine if normal, overweight, and obese people experience different amounts of hunger before eating and satiety after eating. Our hypothesis is there are higher sensations of satiety, and lower sensations of hunger among Normal Weight than Overweight and Obese people. The study compared hunger and satiety levels before and after eating amongst normal, overweight, and obese Body Mass Index (BMI) categories using a Labeled Magnitude Scale (LMS). Forty-five subjects (29 normal, 13 overweight, and 3 obese) rated thirty phrases using LMS hunger and satiety scales. The scale was 100 mm in length having the intensity descriptors of hunger and fullness as follows: strongest imaginable sensation, extremely, very, moderately, slightly, barely detectable, no sensation. Because there were so few obese people, I grouped the overweight and obese answers to compare with the normal weight answers. The results for the first ten survey questions, which were situational hunger and fullness questions, typically showed overweight and obese people being hungrier than normal weight people, for example “how hungry/full do you feel after not have eaten for 24 hours.” Overweight and obese people were fuller than normal weight people when the scenarios were more geared towards fullness, for example, “after a complete Thanksgiving dinner.” The last twenty survey questions were specific food questions that displayed the overweight and obese people less hungry after eating the item in comparison to normal weight people. In addition, the averages of the overweight and obese people for the specific food questions presented the overweight and obese people being fuller than normal weight people after eating the various foods asked in the survey.
Effects of various emulsifying salt concentrations and cheese types in reduced sodium process cheese
(2012-04-18) Saputra, Ern
Process cheese is manufactured by blending continuously and heating one or more types of natural cheese in the presence of emulsifying salts and other nondairy ingredients to form a homogenous plastic mass. Although the process produces a product with extended shelf life and numerous enduse applications, the sodium content of the final product also increases. Therefore, process cheese is used in a wide variety of food products, widely consumed and often contribute to hypertension and other related disease. The objective of this research was to reduce the sodium content in process cheese and to examine the textural properties as well as consumers’ acceptance on reduced sodium process cheese. Four different treatments of process cheeses were manufactured at different sodium level (full sodium control, 18%, 26% and 44% reduction of sodium) using a Thermomix TM 31, a food blender and processer. The samples were then tested for their chemical components. The textural characteristics of the process cheese were analyzed by Texture Profile Analysis (TPA) and meltability test and also surveyed for consumer acceptance and sensory perception. The chemical components of all the different treatments were similar and did not contribute significantly to the texture and meltability of process cheese. TPA results showed that the full sodium control and 18% sodium reduction gives more firmness to the cheese as their average hardness were greater than the 26% and 44% sodium reduction. Meltability test showed that as the 26% and 44% reduction of sodium produced cheese with higher meltability than the full sodium control and 18% sodium reduction. Sensory analysis also showed that as the amount of sodium in cheese was reduced, the resulting products were less firm and the amount of work required to chew the process cheese was less. Sensory results showed that the saltiness level of the 44% sodium reduction was the highest and the full sodium control was the lowest. The sensory panelists failed to notice the difference in saltiness as the sodium content in process cheese was reduced. It also showed that highest value of off-flavors increases as the percentage of sodium reduction is higher.

University Digital Conservancy

Browse by Subject

Browsing by Subject "College of Food, Agricultural and Natural Resource Sciences"