Master of Science / Department of Agricultural Economics / Ted Schroeder / Demand indices are used by many industries as a measurement tool to track changes and make yearly comparisons. Many different sources use demand indices to track the demand for beef. Indexes are an important tool to help better understand why demand shifts the way that it does and help strategically plan for the future of the industry. There are a wide variety of beef demand indices out in academia and many are constructed in different ways. This study advances the literature by testing which factors of index construction effect the results the greatest. This study tested four separate factors in the construction of demand indices. These iterations are as follows, changes in retail price data, changes in elasticities chosen, changes in export data, and changes in construction in terms of quantities instead of prices. Changes in retail price data do not appear to be statistically different. All estimates in this study where elasticities were changed appear to be different statistically, however the level of concern with this finding may be minimal due to the small increments of change in magnitudes of difference between indices. Results from omitting export data does appear to result in statistically different indices, but again the level of concern with the difference may be small. Finally, index construction in terms of prices versus construction in terms of quantities does not appear to have statistically different results, as the indices in this comparison move similarly. For all practical purposes in industry, it does not appear to matter which index is chosen for comparisons, as long as one remains consistent with which index is chosen for comparisons.

Master of Science / Department of Agricultural Economics / Andrew P. Barkley / Andrew P. Barkley / This research will identify and quantify the determinants of international wheat trade from 1999-2008. This study will focus on the following objectives: (1) Review literature on international wheat trade to develop a suitable conceptual model (2) Quantify the impact of economic variables including price, income, exchange rates, transportation costs, and trade policies; and (3) Extend previous work by further consideration of trade policies and international relationships. Regression results indicate that economic factors continue to play a major role in wheat trade. Domestic price had the largest level of statistical significance of non-trade agreement factors in this analysis. The regression results highlight that national income, distance between nations, exchange rate, inflation and respective populations are also important in determining the flow of wheat. Openness to trade and agriculture production variables were statistically significant, demonstrating the commodity nature of wheat trade. Sharing a common border and language are also positive factors in wheat trade. Colonial heritage does have some small impacts, negative for direct colonies and positive for nations sharing a common colonizer. This analysis extends previous international wheat trade research through the inclusion of multilateral relationships and bilateral trade agreements. This study showed that not being a member of the WTO is a positive factor in the trade of wheat. The review of trade agreements added depth to this study by examining both trade creation and trade diversion for each agreement specifically for their effects on wheat trade. The estimated models show that nations which develop agreements with contrasting qualities from themselves are likely to see higher gains from free trade agreements. However, when nations engage in agreements with nations in a similar location or income structure, trade diversion iv occurs. The analysis also shows that trade agreements can overcome factors that may have a negative impact on the trade of wheat such as distance or colonial relationships. By understanding the determinants of wheat trade, players in the wheat market can create a more transparent and fluid trading system.

Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Khatamian Houchang / This project investigated the physiological and biochemical responses of three grapevine genotypes to a deficit irrigation strategy termed partial rootzone drying (PRD). The principle objectives of the project were to (1) establish if the response to PRD is a unique vine physiological response; (2) to investigate the effect of PRD on berry maturation and composition; (3) effect of PRD on vine water-use efficiency; (4) investigate the hormonal signal involved in the PRD mechanism. In addition, the project investigated the adaptation of these three grapevine genotypes to Kansas climatic conditions. The irrigation project was conducted in both a greenhouse at Kansas State University, Manhattan, KS, and field conditions in an experimental vineyard at the John C. Pair Horticultural Research Center, Haysville, Kansas. The greenhouse study was replicated four times (6 months each run) and the field study ran from the 2005/2006 season through the 2006/2007 season. Application of PRD to vines resulted in a unique physiological response distinct from other established deficit irrigation procedures such as regulated deficit irrigation (RDI); however, the overall physiological responses of the vines were defined by the environmental conditions of the vineyard where the experiment occurred. Reduced water availability, low to medium vigor vines, restricted root development, and high evaporative demand were all factors in the vines response to PRD. Under these conditions, PRD did maintain the yield at deficit irrigation rates compared to fully irrigated vines, and was responsible for physiological changes in the vine that could have long-term implications for yield stability. The application of PRD resulted in an improvement in plant water status and maintenance of leaf function as measured by photosynthesis, stomatal conductance and leaf water potential throughout the season.

Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Kimberly A. Williams / Despite extensive evidence that appropriate use of floral preservatives extends postharvest longevity of most fresh flowers, their use by traditional full-service florists has been observed to be highly variable. This research was developed to determine if knowledge about floral preservatives increases consumers’ perception of quality, purchase intention, and price of a floral arrangement. A survey was administered to 222 participants at two locations in Manhattan, Kansas during April 2010. Seventy-three percent of respondents fell within the age range of Gen Y. The survey instrument contained four levels of presentation of a floral arrangement that were associated with increasing knowledge about the use of a floral preservative on consumers’ perceptions about the quality and price of that arrangement. Results were analyzed via within-subjects ANOVA, Bonferroni post-hoc tests, t-tests, and regression analyses. Participants of the survey rated the quality of a floral arrangement higher from Level 2 (presence of floral preservative not explicit) to 3 (presence of floral preservative explicit) and Level 3 to 4 (after reading 191 word count message about floral preservative function and effectiveness). Their intent to purchase the floral arrangement generally increased with each level of presentation. Participants increased the price that they were willing to pay for the floral arrangement at each level of presentation, starting at $25.49 at Level 1 (no floral preservative use indicated) to $29.17 at Level 4. Participants were more knowledgeable about the benefits of floral preservatives and believed that floral preservatives increased the value of floral arrangements after reading a message describing their function and effectiveness more so than before reading the message. Younger participants were more willing to pay more for floral arrangements with floral preservatives than older participants. As consumers become more aware of the use of floral preservatives and more knowledgeable about how and why they are effective, they attribute higher quality to floral arrangements with preservatives, are willing to pay more for arrangements with preservatives, and their purchase intention frequency increases. Florists should consider providing a message about the function and effectiveness of floral preservatives to their customers, and then market their use of these materials.

Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Dale J. Bremer / Radiometric methods may provide more objective and quantitative assessments of turf quality and density than visual ratings and may be useful in measuring green leaf area index (LAI), aboveground biomass, and chlorophyll concentration. This three-year study was conducted near Manhattan, KS to examine: 1) relationships between canopy reflectance and visual quality and density ratings in four cool-season grasses tall fescue (Festuca arundinacea Schreb.), Kentucky bluegrass (Poa pratensis L.) and two hybrid bluegrasses (HBG); 2) effects of species, mowing height, and irrigation deficit on relationships between visual quality and reflectance; 3) comparisons of visual quality with reflectance and digital images of individual plots; and 4) relationships of LAI, aboveground biomass, and chlorophyll concentration with canopy reflectance in the same four grasses and in perennial ryegrass (Lolium perenne), zoysiagrass (Zoysia japonica Stued.), and bermudagrass [Cynodon dactylon (L.) Pers.]. Reflectance was strongly correlated with visual ratings in the normalized difference vegetation index (NDVI, [935-661]/[935+661] nm, r = 0.88), the near infrared to red (NIR/R [935/661] nm, r = 0.83), Stress1 (706/760 nm, r= 0.84), and Stress2 (706/813 nm, r= 0.70) ratios and at wavelengths 613 (r= 0.74) and 661 nm (r = 0.80), but correlations varied among years at each wavelength and vegetation index. For density, highest correlations were in NDVI (r=0.86), R661 (r=-0.84), and Stress2 (r=-0.82). Regressions between reflectance and quality and density ratings indicated cultivar- and mowing height-specific models. Irrigation-deficit strongly affected reflectance in KBG and both HBG but not in TF, indicating greater sensitivity to drought of bluegrasses than TF. Digital images indicated strong correlations between percentage green cover and visual quality (r=0.89). However, wide ranges in visual quality were observed in plots with similar green cover or NDVI for reasons that are not apparent. Correlations of LAI, aboveground biomass, and chlorophyll concentration with reflectance were strong in some species at different wavelengths and ratios. Results indicated both potential and limitations in using spectral reflectance to estimate turfgrass canopy characteristics.

Master of Science / Department of Animal Sciences and Industry / David M. Grieger / Mares in estrus can exhibit erratic and fractious behavior that may adversely affect their ease of handling. Current treatments for suppression of estrus in the mare include an oral progestin, Regu-mate® (Hodgson et al., 2005), uterine insertion of a glass ball (Nie et al., 2003), fetal crushing through rectal palpation (Lefranc, 2004) and surgical sterilization (McCue, 2003). Although effective, all of these procedures are problematic for different reasons. Immunization against an endogenous hormone critical to fertility is an attractive alternative in suppressing estrus; especially if it is less intrusive and reversible. This strategy has been demonstrated by targeting gonadotropin-releasing hormone (GnRH) in gilts (Esbenshade and Britt, 1985), ewes (Clarke et al., 1978), mares (Garza et al., 1986), and heifers (Johnson et al., 1988). The antigen developed for this study was produced using the sequence of the bacterial protein, glutathione-S-transferase (GST) linked to three in-tandem repeats of the mammalian GnRH gene coding sequence (GST-GnRH3). Six reproductively sound mares, between the ages of 3 and 8 years, were used in this study. The anti-GnRH group (n=4) received 1 mg of GST-GnRH3 in 2ml of incomplete Freund’s adjuvant (IFA) as the primary injection. Four weeks later, mares received a single booster injection of 0.5mg of GST-GnRH3 in 1ml of IFA. The control mares (n=2) received similar doses of GST protein only, in identical injection volumes of IFA as the anti-GnRH group. The entire duration of the study ran for 22 weeks from early May through September. Ovaries were monitored three times weekly to track follicular growth and ovulation via transrectal ultrasonography. In addition, all mares were exposed to a stallion twice weekly and observed for estrous behavior. Weekly blood samples were collected to evaluate progesterone levels and serum binding of GnRH. The GST-GnRH3 antigen suppressed follicular activity in all treatment mares within 45 days following the second injection. Estrous behavior was suppressed in all but one mare in the anti-GnRH group. When exposed to the stallion, this mare displayed strong estrous behavior for seven weeks despite her lack of ovarian cyclicity. Follicular activity and estrous behavior remained normal in one of the control mares (avg. cycle length = 20 days). For the final 10 weeks of the study, however, the other control mare developed large follicles but failed to ovulate according to the ultrasound data. This mare did not display estrous behavior during this period, and her progesterone levels remained greater than 2 ng/ml for most of the final 10 weeks of the study. Approximately 2 weeks after the booster injection all anti-GnRH mares had progesterone levels of <1ng/ml. GnRH antibody binding peaked two weeks following booster immunization in all treated mares and remained undetectable in control mares throughout the study. The GST-GnRH3 treatment induced GnRH binding, suppressed follicular activity and reduced progesterone concentrations in all four mares. Although estrous behavior was abolished in 3 of the 4 treated mares, one did continue to demonstrate estrous behavior in the presence of a stallion. This dissociation of ovarian activity and estrous behavior was evident in our study with a limited number of animals, but the vaccine does show promise in reducing unwanted estrous behavior.

Master of Agribusiness / Department of Agricultural Economics / Michael Boland / The Western Sugar Cooperative is a 135,000 acre sugar beet processing cooperative headquartered in Denver, Colorado with sugar beet processing factories located in Ft. Morgan CO, Torrington WY, Scottsbluff NE, Lovell WY, and Billings MT. The objective of the thesis is to analyze alternatives for maximizing the net revenue of co-products at Western Sugar. The ethanol policies of the U.S. government have had many unintended consequences including increasing the price of corn which is a key ingredient in animal feed production. Sugar beet co-products are produced in fixed proportions. That is, for every unit of sugar produced a corresponding unit of sugar beet pulp is created which is mostly water. Historically this has been dried into an animal feed pellets, however removing water from any high volume and high speed manufacturing process is energy intensive. Natural gas prices have increased dramatically and are projected to stay that way for a long time. As a result, the cost of manufacturing pellets is very high. The research shows that we are able to significantly increase our net income by increasing the percentage and price of pressed feed pulp rather than drying the pulp into pellets. This equals 20 million dollars of revenue in our pulp product line for the 2008-2009 sugar beet campaign. The thesis contains various analyses for changes in critical costs and prices. More importantly it details the subsequent management decisions implemented to maximize net income in the co-products business.

Master of Science / Department of Grain Science and Industry / Sajid Alavi / Extrusion is a popular technology for production of expanded products. However, variability in multiple input parameters can lead to significant variations in the end product which becomes a concern for process control and efficiency in industries. This study was focused on understanding the uncertainty in input parameters during extrusion and their impact on variability in output. A mechanistic model was developed for bubble growth dynamics in starch based melts at microscopic and macroscopic levels using heat, mass and momentum transfer equations. This model was used for uncertainty simulations using the Monte-Carlo method by integrating it with a stochastic interface for input of randomly generated process data based on experimentally obtained distributions and output of simulated distributions of end-product properties such as expansion ratio (ER). A pilot-scale twin screw extruder was used for processing of corn-based expanded products, which was used as a model system for experimental validation of the mathematical model. A 4x2 factorial design was used with different in-barrel moisture contents (19, 23, 28 and 33% dry basis) and extruder screw speeds (250 and 350 rpm) to measure process data (such as moisture injection rate and T[subscript]d[subscript]i[subscript]e) and product characteristics (such as ER). Average experimental ER ranged from 2.33-10.88 and simulated ER ranged from 1.16-12.86, where both had similar trends with respect to in-barrel moisture (MC) and die temperature (T[subscript]d[subscript]i[subscript]e = 108.8-145.4˚C) although conditions for optimum expansion differed possibly due to non-correspondence of material properties. Experimental coefficient of variation (CV) for MC (0.6-1.6%) and T[subscript]d[subscript]i[subscript]e (0.29-0.91%) and an assumed CV of 2% for a material constant (k[subscript]f) that controls the consistency index of starch-based melt were used for simulations. The stochastic model was used to carry out sensitivity analysis for CV of ER with respect to CV of MC, T[subscript]d[subscript]i[subscript]e and k[subscript]f. Variability in ER was impacted the most by variation in T[subscript]d[subscript]i[subscript]e, followed by MC with k[subscript]f having relatively lower impact on it. Since there are fundamental flaws in modeling approach as reflected by the thermodynamically infeasible parameter dynamics, the results from these mechanistic or stochastic simulations cannot be used as a basis for scientific analysis.

Master of Science / Department of Grain Science & Industry / Yong-Cheng Shi / The objective of this study was to systematically understand the changes of rice during the parboiling process. Isolated rice starch, milled rice and paddy rice kernels of the same variety (18% amylose) were examined after steeping at temperatures (60-75 oC) below and above the onset of rice starch gelatinization temperature for different durations in 66.7% water. Changes in gelatinization temperatures were greater for isolated starch ˃> milled rice ˃ paddy rice. Annealing above samples’ original To caused partial gelatinization, loss of crystallinity, and birefringence as determined by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and light microscopy. However, starch granules in milled rice and paddy rice, which were surrounded by non-starch components, maintained their granule integrity. Scanning electron microscopy (SEM) revealed morphological differences between starch granules within native and steeped rice kernels. Steeped kernels had denser structures than native kernels, as determined by high resolution X-ray microtomography. Rice starch granules and kernel characteristics were altered significantly during steeping and changes in isolated starch differed from those inside the rice kernels. To study the changes during the steaming process, the morphology of the rice kernel and starch granules within the kernel were examined immediately after heating at110oC for 20 min. Starch was completely gelatinized as determined by DSC and XRD, indicating the disruption of all short-range crystallinity of starch in parboiled rice. However, SEM showed intact starch granules and light microscopic images showed starch granules embedded in the rice kernel. Interestingly, these granules displayed Maltese cross patterns. For the first time, we demonstrated that starch granules were birefringent and showed the Maltese cross but were not crystalline.

Master of Science / Department of Grain Science and Industry / Yong-Cheng Shi / Jon M. Faubion / One long-term goal of cereal science research is to increase the shelf life of baked products and one approach to that goal has been the use of emulsifiers. Emulsifiers are surface-active agents, some of which improve specific properties of baked products. Two emulsifiers, sodium stearoyl lactylate (SSL) and oleyl lactylic acid (OLA) are similar in structure, the difference being the acid moiety: stearic versus oleic acid. Widely researched, SSL has found many uses in baked products. However, how OLA interacts with starch/flour in baked products or how that interaction affects product quality is not well understood. The objective of this study was to understand the interactions between normal wheat starch and these emulsifiers, as well as the differences between SSL and OLA in those regards. The effects of the two emulsifiers on the pasting properties of wheat starch and wheat flour were determined using a MicroViscoAmylograph. Heating at 6oC/min with increased emulsifier concentration (0-2%) resulted in increased hot paste viscosity and apparent interaction of both emulsifiers with wheat starch. Solid content affected both maximum hot and final viscosity. OLA produced increased maximum hot and final viscosities with increased starch concentration and emulsifier concentrations. For wheat flour, higher concentrations of SSL reduced both maximum hot paste and final viscosities. OLA behaves differently with wheat flour. At lower flour concentrations, higher concentrations of OLA reduced maximum hot viscosity. The effects of SSL on starch were affected by an increased heating and cooling rate (10oC/min). Heating stage microscopic analysis revealed that the presence of emulsifiers inhibited granular swelling beyond the normal gelatinization temperature (65oC) in both starch and flour systems. OLA’s effect in this respect was greater than that of SSL. Complex formation between emulsifiers and wheat starch and wheat flour was determined using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). For isolated wheat starch and hard wheat flour, DSC and XRD indicated that OLA complexes to a greater extent than does SSL. For flour, XRD indicated no difference exhibited in the interaction of the emulsifiers with the flours. KEYWORDS: Emulsifiers, Starch, Wheat flour