Master of Science / Food Science Institute / J. Scott Smith / Carboxymethyllysine (CML) and other advanced glycation end products (AGEs) have been shown to affect diseases such as diabetes, cancer, and Alzheimer’s by inducing oxidative stress, inflammation, and tissue damage. CML is formed in foods through Maillard browning reactions and through various mechanisms that are affected by time, temperature, pH, water activity, trace metals, and antioxidants. Natural antioxidants can be found in plant and fruit extracts, as well as in spices. The research contained herein is in two parts. The first part includes preliminary work, which examines the percent recovery of CML from various solid phase extraction columns, the analysis of CML in maple syrup, barbeque sauce, honey, and infant formula. The data show that solid phase extraction with a C-18 cartridge produced the highest percent recovery when using a CML standard at 100 ppb, with a recovery of 69%. Furthermore, the analysis of the syrups and sauces is inconclusive, due to the very low levels of CML detected in the infant formula, and the complications due to the high levels of reducing sugars. The second part of the research examines the effect that cinnamon, onion, garlic, black pepper, and rosemary have on CML levels in biscuits. The data show that all of the spices inhibit the formation of CML, at each of the 0.5%, 1%, and 2% levels used in the experiment, by a minimum of 3% in 2% onion samples and a maximum of 79% in 0.5% cinnamon samples when looking at the cumulative data. When looking subsets of the data, the CML inhibition was a minimum of 59% in 2% onion samples and a maximum of 74% in 0.5% cinnamon samples. Other trends can be observed in the chroma values in the CML color data, which suggest that chroma values decrease as the spice level increases, but these are not statistically significant. They may be due to color from the spices themselves, or to the chemical changes in the Maillard reaction.

Doctor of Philosophy / Department of Human Nutrition / Edgar Chambers IV / Because healthy food products do not have a specific tool used for consumer screening based on consumers’ diet or degree of healthy eating habits, this study aimed to determine a set of questions that could classify consumers who belong in a different status according to the Stages of Change model, including those who have a different diet quality based on their Healthy Eating Index (HEI) score. The surveys were conducted in the United States (US) and Thailand in order to determine applicability to varying countries. The Food Neophobia Scale (FNS), Food Involvement Scale (FIS), and Health and Taste Attitude Scale (HTAS) were included in the questionnaire together with a set of Stages of Change questions and a 7-day, self-administered food recall questionnaire. The HEI interpretation of US and Thai consumer scores illustrated that the majority of both belonged to the Need Improvement group. The Stages of Change model indicated most consumers thought they had healthy diets. According to FNS, FIS, and HTAS, US consumers are more involved in food activities and are more open to trying new foods or unfamiliar foods than Thais. Furthermore, consumers who belong in different groups, according to the Stages of Change model, responded differently to some HTAS subscales. However, statements from FNS, FIS, and HTAS were not capable of distinguishing consumers belonging in different groups according to HEI scores or belonging in different stages according to the Stages of Change Model. Considering all possible methods from those listed above for screening consumers, the Stages of Change model may be the best way to segment consumers interested in healthier eating. Using the Stages of Change required less time and the least effort from consumers because there were only three questions; and interpreting results does not require calculation or analysis.

Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / A total of 48 carcasses were taken from a larger trial using 288 pigs (PIC TR4 × 1050, initially 58.9 kg) in a 73 d feeding study to determine the effects of sorghum dried distillers grains with solubles (S-DDGS) in sorghum- or corn-based diets on ground pork quality. The dietary treatments included: sorghum-based diets with 0, 15, 30, or 45% SDDGS, a sorghum-based diet with 30% corn DDGS (C-DDGS) and a corn-based diet with 30% C-DDGS. Shoulders from 24 barrow and 24 gilt carcasses were ground and evaluated for proximate and fatty acid composition, iodine value (IV), objective color, thiobarbituric acid-reactive substances (TBARS), and sensory attributes. No finishing diet × gender interaction was detected for composition, fatty acid profile, color or TBARS (P > 0.05). Pork from gilts contained less fat and more moisture (P < 0.001), was less saturated with a greater IV and total percentage of PUFA (P < 0.01), and also had a lower L* value (P < 0.001) and higher a* value (P = 0.006) than pork from barrows. Gender did not affect total color change ( E) from 0 to 120 h (P = 0.30), TBARS (P = 0.08), or sensory attributes (P ≥ 0.32). Finishing diet had no affect on total fat, moisture, or protein composition (P ≥ 0.18). Increasing S-DDGS resulted in a linear (P < 0.001) decrease in SFA and MUFA and an increase (P < 0.01) in PUFA and ground pork IV. Pork from pigs fed 30% S-DDGS had a greater percentage of MUFA (P = 0.01) and a lower percentage of PUFA (P > 0.006) and reduced IV (P = 0.03) compared to pork from pigs fed the sorghum-based diet with 30% C-DDGS. Diet did not affect TBARS (P = 0.37) or L*, a*, or b* values (P ≥ 0.11) but was shown to influence E (P = 0.01) with pork from pigs fed sorghum grain and 30% S-DDGS having less total change than all other treatments. It is concluded that consumers will not be able to differentiate ground pork from pigs fed DDGS and that feeding sorghum grain and S-DDGS can be done without affecting ground pork quality.

Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / Douglas Powell / Randall Phebus / Not-ready-to-eat entrées purchased at retail and prepared in the home have been identified as a risk factor for salmonellosis. From 1998 to 2010, ten outbreaks implicated undercooked not-ready-to-eat entrées. In each outbreak, affected individuals prepared entrées in a microwave oven, did not follow recommended cooking instructions, and failed to take the internal temperature of the cooked product. This dissertation surveyed grocery stores for product availability, evaluated consumers’ preparation practices of raw, breaded, frozen chicken entrées, and validated on-package label instructions. The survey of retail revealed that several manufacturers fail to provide consumers clear preparation instructions. A video capture system was used to observe food preparation practices of 41 consumers–21 primary meal preparers and 20 adolescents–in a mock domestic kitchen using uncooked, frozen, breaded chicken products, and determined if differences exist between consumers’ reported safe food handling practices and actual food handling behavior as prescribed on product labels. Differences between self-report and observed food safety behaviors were identified between groups. Many participants reported owning a food thermometer (73 percent) and reported using one when cooking raw, breaded chicken entrées (19.5 percent); however, only five participants (12.2 percent) were observed measuring the final internal temperature with a food thermometer despite instructions on the product packaging to do so. Food handling errors identified during the meal preparation sessions were then mimicked in a controlled laboratory setting to determine the impact of such deviations on end-product temperature. For all products, highly variable internal temperatures were recorded across entrées when prepared in a 600W microwave oven. Microwave cooking of raw breaded poultry products is unpredictable in achieving uniform target end-point temperatures; however, a 1000W microwave oven consistently produced a safe end product. Data collected through direct observation more accurately reflected consumer food handling behaviors than data collected through self-reported surveys. Low wattage microwave ovens failed to produce a safe end product. Processors should validate instructions for not-ready-eat entrées using a range of microwave ovens rather than a single wattage, develop a unique set of instructions for entrées, and provide consumers clear cooking instructions that result in a safe end product.

Master of Agribusiness / Department of Agricultural Economics / Arlo Biere / The purpose of the research reported in the thesis, here, is to quantify new value added possible in flour milling with the use of the SDmatic monitor, produced and sold by Chopin Technologies SAS. As an employee of Chopin, part of my responsibility is to market the SDmatic. The SDmatic was designed and is marketed to improve flour quality by providing automatic monitoring of starch damage in flour—damaged starch affects dough characteristics, which affects baking quality and the ideal damaged starch differs by type of bakery product. While the SDmatic is so marketed, Chopin, now, realizes that SDmatic might also benefit a flour miller by increasing operational efficiency of the mill, specifically by reducing the electrical energy used in milling. If that can be done, it would improve mill profitability, reduce energy demand and, thus, reduce the pressure on the climate and environment from energy production. To address that possibility, the thesis research studied the relationship between energy usage and damaged starch in the flour and, then, estimated the cost savings possible by using the SDmatic to mill flour to specifications most efficiently. Finally, those results were used to estimate the return on investment in the SDmatic from improved mill efficiency, alone. The research shows improvement in energy efficiency is definitely possible with better management and targeting of the level of starch damage in flour production. Such improved management is possible, today, because SDmatic dramatically reduces the difficulty and time required to measure damaged starch. Such monitoring has not been done in the past because of the cost and time involved with prior methods. SDmatic makes that possible and cost effective, now.

Master of Science / Department of Food Science / Elizabeth A. Boyle / Animal production factors can affect nutritional composition and quality of poultry meat. Quality attributes and fatty acid composition were evaluated on breast and thigh meat with skin from free range, heritage bred chickens (>116 day of age) (HB) and commercial broilers (<50 day of age) (CM). In addition, sensory and textural attributes were evaluated on breast and thigh meat of HB, and air or water chilled CM. Moisture and fat content was similar (P>0.05) between chicken types without skin. Thigh meat had at least 2.41% more fat (P<0.05) than breast meat; however, breast meat had at least 2.33% more moisture (P<0.05) regardless of skin inclusion or chicken type. Heritage meat with or without skin had a greater amount (P<0.05) of ω3 polyunsaturated fatty acids (PUFA) than CM regardless of chilling type and HB had a lower, more desirable ω6:ω3 ratio of 12.79 when compared to air or water chilled CM at 15.20 and 14.77, respectively. Heritage breast and thigh meat with skin contained 35.60 and 35.21% PUFA which was greater than (P<0.05) CM breast and thigh meat with skin at 20.96 and 20.45%, respectively. Whole carcass weight of CM, breast weight, and bone-in thigh weight was 71.30%, 148.0%, and 52.2% heavier (P<0.05), respectively, than HB weight. However, bone-in thigh yield was 2.1% higher (P<0.05) in HB. Commercial broiler breast and thigh meat was more tender (P<0.05) with higher myofibrillar tenderness and overall tenderness values and having less connective tissue than HB breast and thigh meat. Thigh meat from HB also had the highest (P<0.05) peak force values for Warner-Bratzler (3.47 kgf) and Allo-Kramer (7.22 kgf/g sample) shear tests. Thigh meat was perceived to be more juicy (P<0.05) and have more chicken flavor intensity (P<0.05) than breast meat. Heritage meat showed advantages in fatty acid profiles while CM meat showed advantages in yields and tenderness attributes.

Master of Science / Department of Hospitality Management and Dietetics / Elizabeth B. Barrett / The Centers for Disease Control estimates that each year 48 million Americans become ill, 128,000 are hospitalized, and 3,000 die of foodborne diseases. In 2011, the CDC reported that Norovirus caused the majority of all foodborne diseases and can be eliminated with proper handwashing, which is the number one way to prevent the spread of foodborne disease. The purpose of this study was to use the Health Belief Model to determine differences in university foodservice employees’ beliefs and perceptions about handwashing and foodborne illness. The constructs of perceived susceptiblity, severity, barriers, benefits, and self-efficacy as they relate to handwashing were used to examine the differences in demographics. Instrument development included a review of literature, focus group feedback, a pilot study and a review by industry experts. The final instrument was distributed to all foodservice employees at Kansas State University using Qualtrics and pen-and-paper surveys. Frequencies, means, t-tests, ANOVA, and regression were used for data analysis and to answer research questions. Results indicated respondents who were older (above 23 years of age), full-time employees, had more than three years of experience, and were food safety certified had a higher perception of susceptibility, benefits, and self-efficacy of handwashing and its relationship to reducing foodborne illness. Perceived severity was highest among respondents with food safety certification and more than three years of experience. Supervisor/Manager category did not agree on barriers to handwashing in the workplace with other positions; however, most employees did not rate barriers as a problem. Non-white respondents showed a lower self-efficacy for ability to wash hands correctly. Results of this study highlight the need for self-efficacy focused handwashing training for first year and non-white employees.

Master of Science / Food Science Institute / Randall K. Phebus / The USDA declared seven STEC serotypes to be adulterants in raw, non-intact beef products due to their severe health implications. STEC contamination of carcasses is most likely to occur during hide removal. This study evaluated the efficiency of a mixed STEC-7 inoculum to attach to raw beef carcasses (predominantly lean muscle and adipose tissue), and compared the efficacy of 4.5% lactic acid (LA) to a water (W) spray to reduce STEC populations. Four carcass contamination scenarios, representing potential points whereby STEC could come into contact with raw beef surfaces during slaughter operations, were evaluated: (A) pre-rigor surface STEC inoculated (ca. 7 log cfu/cm[superscript]2), 30-min ambient temperature attachment, spray with LA or W; (B) pre-rigor inoculated, 24-h chilled attachment, spray; (C) tissue chilled 24 h, inoculated, 30-min attachment, spray; and (D) tissue chilled 24 h, rewarmed to 30°C, inoculated, 30-min attachment, spray. Predominantly lean muscle and adipose tissue were collected from four fed cattle immediately after harvest and assigned to the four scenarios for STEC inoculation, followed by a post-inoculation water (control) or LA spray. Tissue excision samples were collected pre- and post-treatment and analyzed to enumerate STEC-7 populations. Data were collected in a completely randomized design and analyzed using a mixed-model ANOVA. Pairwise comparisons of treatment means were made at α = 0.05 with p-values adjusted using Tukey-Kramer. Initial STEC attachment levels to predominantly lean muscle and adipose tissues were not significantly different across all scenarios. Scenarios C and D showed greater STEC attachment compared to scenarios B and A. The LA spray reduced STEC levels more effectively than water across all scenarios. A significant treatment by tissue type interaction was observed for STEC reductions. A greater STEC reduction was observed for adipose tissue than for predominantly lean muscle when lactic acid spray was applied. A significant treatment by scenario interaction was observed for STEC reductions. Scenarios A and B presented greater log reductions (1.77 ± 0.27 and 1.85 ± 0.25 log CFU/cm[superscript]2, respectively) than scenario C (1.04 ± 0.10 Log CFU/cm[superscript]2). LA spray presented the same level of effectiveness when applied to pre-rigor warm tissues and chilled tissues for reducing STEC. Greater post-LA spray reductions were observed when STECs were inoculated onto pre-rigor meat surfaces and submitted to a 24 h chill cycle, suggesting that cold storage temperatures (~2 °C) may stress or injure the STEC cells prior to subsequent antimicrobial spray applications to chilled surfaces. For laboratory studies, consideration must be given to when inocula are applied to tissue surfaces to accurately determine and/or compare the effectiveness of antimicrobial treatments. These findings provide insight to beef processors and researchers regarding inoculation protocols for comparative validation studies, and potential impacts on microbiological results from application of antimicrobial interventions at different points during raw beef processing.

Master of Science / Grain Science and Industry / Greg Aldrich / Rendered protein meal is an important source of dietary protein and fat in pet food. However, fats in rendered meals can oxidize rapidly if not protected. The most common measurement of oxidation is the peroxide value (PV), but the analysis is highly variable. Additionally, the incorporation of oxidized protein further shortens its shelf life. Therefore, our objectives were to evaluate methods to measure fat quality in rendered protein meals and to determine the effect of increasingly oxidized protein meals on the shelf life of extruded pet foods. In Experiment 1, samples of five chicken byproduct meals (CBPM) from each of three locations and five beef meat and bone meals (BMBM) from each of two locations were analyzed for PV, anisidine value (AV), and thiobarbituric acid reactive substances (TBARS). The PV varied by method and location (P < 0.05). The alternative oxidation analytical methods, AV and TBARS, were not strongly correlated to PV (R² > 0.01). In Experiment 2, one metric ton of each unpreserved CBPM and unpreserved BMBM were collected and left unpreserved (U) or preserved with either ethoxyquin (E) or mixed tocopherols (T). These were held at ambient conditions (25°C, 51% RH) and monitored for PV and AV until values plateaued (41 and 63 days for CBPM and BMBM, respectively). Each “aged” meal was then incorporated into a model extruded cat food diet (~30% protein). Samples of kibble for each treatment were collected and stored at an elevated temperature and humidity (40°C, 70% RH) for 18 weeks and an ambient temperature and humidity (~22°C, 45% RH) for 12 months. The initial reduction (P < 0.05) in PV of the U (highly oxidized) BMBM and CBPM after processing suggests oxidation levels were diluted by food production. The oxidized meal led to a shorter shelf life (P < 0.05) in the finished food by PV analysis; but, sensory analysis by quick assessment did not completely corroborate these findings. These results suggest that PV doesn’t fully describe rendered protein meal stability or have a direct impact on shelf life for consumers; but may have a negative impact on pets due to oxidized lipid consumption.

Master of Science / Food Science - Animal Sciences and Industry / J. Scott Smith / Heterocyclic amines (HCAs) are a class of mutagenic and carcinogenic chemical compounds formed on the outside of meat and fish when cooked at high temperatures. 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most abundantly formed HCA. HCAs have been found to cause cancer in mice and rats; PhIP specifically has been found to cause breast, rectal, prostate, and colon cancers. Model systems are often used to replicate the HCA chemical reactions in meat products without causing the many side reactions when meat is cooked at high temperatures. Model systems are also a useful way to study the effects of different variables and compounds on the formation of HCAs without using meat. A model system using amounts of 0.2 mmol glucose, 0.4 mmol creatinine, and 0.4 mmol phenylalanine in 10:90 water/diethylene glycol (v/v) was used to study the formation of PhIP. Differing levels of black pepper oil, black pepper extract, and rosemary extract (36, 71, 142, 285, 550 μL), synthetic antioxidants BHT and TBHQ (0.05 mmol, 0.1 mmol, 0.2 mmol, 0.4 mmol), and piperine (4.02 mg, 8.04 mg, 16.14 mg, 31.14 mg) were added to the model system to study their effect on PhIP formation. PhIP formation with added BHT (0.2 and 0.4 mmol) and TBHQ (0.4 mmol) were not significantly different from the control. All other added compounds decreased PhIP formation significantly from the control at p < 0.05. Solid phase micro extraction (SPME) headspace analysis was conducted on ground black pepper, black pepper oil, and black pepper extract to determine possible components responsible for PhIP inhibition. Six volatile compounds were found in common between ground black pepper, black pepper oil, and black pepper extract: 1R-α-pinene, 3-carene, caryophyllene, α-caryophyllene, cyclohexene, and D-limonene. D-limonene and caryophyllene had the largest peak areas, suggesting those compounds may play a part in PhIP inhibition in model systems.