Department of Food Science and Human Nutrition
Permanent URI for this community
This digital collection includes theses and dissertations from the Department of Food Science and Human Nutrition.
Browse
Browsing Department of Food Science and Human Nutrition by Issue Date
Now showing 1 - 20 of 83
Results Per Page
Sort Options
Item Open Access Sensory and functional properties of monosodium glutamate(Colorado State University. Libraries, 2002) Giovanni, Maria Elizabeth, author; Stone, Martha B., advisor; Maga, Joseph A., advisor; Allen, Kenneth D., committee member; Kinnamon, Sue C., committee memberFlavor potentiators have been used for centuries to improve food flavor. However, neither the taste transduction mechanisms nor the behavior of flavor potentiators in food are fully understood. The objectives of this research were: 1. To determine the relationship between salivary glutamate and perception of MSG and NaCl; 2. To characterize the time-intensity profiles (TI) of flavor potentiators; and, 3. To determine the effects of heat treatment and pH on levels of L-glutamic acid in simple food systems. The first study consisted of collecting whole mouth saliva and determining thresholds to and perceived intensities of MSG and NaCl. A preliminary experiment indicated that perception of MSG may be influenced by salivary glutamate, gender, and ethnicity. The principal study with 60 subjects found no effect of ethnicity or gender on salivary glutamate or sodium levels. Female Asians had higher salivary sodium and rated the lower concentrations of NaCl as more intense. Psychophysical measures of MSG and NaCl were independent of salivary levels. Twenty subjects, trained in TI methods, evaluated 20 samples of MSG, IMP, and GMP, singly and in combination. The TI profiles generated were atypical of other taste modalities. Time to maximum intensity was brief, followed by a plateau phase at maximum intensity with a long aftertaste. Sample intensities varied significantly, with mixtures of 10 and 5 mM MSG and 2.5 mM IMP and GMP having highest intensity and duration. These results indicated that flavor potentiators may increase total flavor in the mouth. Synergism among flavor potentiators was demonstrated. To determine the effect of pH and heat on L-glutamic acid, 0.1% MSG was added to eleven simple food systems. Percent recovery was highest for tomatoes and lowest for beef broth. Fish broth and tomatoes had higher recoveries at pH 6 than pH 3; thus, pH altered L-glutamic acid levels. No effect of heat on L-glutamic acid levels was found. The sensory and functional behavior of MSG is governed, in part, by the individuality of the subject, its temporal response, and the food system in which it is used.Item Open Access Evaluation of antioxidant and sensory properties of selected cultivars of Colorado-grown lettuce (Lactuca sativa L.)(Colorado State University. Libraries, 2007) Bunning, Marisa, author; Kendall, Patricia, advisor; Stushnoff, Cecil, advisorEpidemiological evidence has substantiated the health benefits associated with the consumption of vegetables, particularly leafy greens. Lettuce (Lactuca sativa L.) cultivars (varieties) have usually been selected based on shelf-life, transportability, and yield rather than nutritional or sensory traits. Information on the effects of seasonality and genetics on various characteristics of lettuce is limited. Nutritional, antioxidant, and sensory profiles of lettuce may vary considerably among cultivars and in response to environmental factors that may fluctuate widely throughout the growing season. Bitterness, an important flavor characteristic of lettuce, is generally thought to increase with higher growing season temperatures and may vary with phenolic content.Item Open Access Diabetes education in Oman: needs assessment and development of an intervention for health care professionals(Colorado State University. Libraries, 2007) Al-Subhi, Lyutha Khalfan, author; Kendall, Patricia, advisor; Adams, Elizabeth, advisorOman is one of the countries faced with the challenge of an increasing rate of diabetes. The National Diabetes Control Program (NDCP), in Oman, aims to provide a suitable and quality health education to people with diabetes and the community. Diabetes management guidelines for Primary Health Care (PHC) in Oman point out that all members of the diabetes health care team share the responsibility of educating those with diabetes. Nevertheless, diabetes education has not been tackled systematically and the incidence of diabetes is on the rise in Oman. There is a pressing need for a diabetes education program for diabetes self management in the Sultanate of Oman.Item Open Access Post-harvest treatment effects on quality and safety characteristics of melons and tomatoes(Colorado State University. Libraries, 2008) Troxell, Heather LeAnne, author; Kendall, Patricia, advisorProduction, processing, and transport of high quality, safe, and healthful produce presents a constant challenge. Calcium chloride (CaCl2) dips have been shown to help maintain fruit quality after harvest by delaying senescence, reducing postharvest decay, and controlling many physiological disorders in fruit. There is little research available, however, assessing the effects of CaCl2 on sensory, nutritional, and microbial qualities of fresh, whole produce, including melons and tomatoes. This research project evaluated the impact of post-harvest storage temperature and use of a CaCl 2 dip on selected organoleptic, nutritional, and microbiological qualities of organic and conventional Colorado-grown melons and tomatoes over time. Melons (cultivars 'Haogen' and 'Arava') were grown on conventional and certified organic plats and tomatoes (cultivar 'Early Girl') were grown on certified organic plots during summer 2007 with controlled pre-harvest, harvest, and post-harvest conditions. All produce was picked at peak maturity and either dipped in a CaCl2 solution or not treated, then stored at 10° ±1° or 21° ±1° C. A variety of sensory, nutritional, and microbial tests were conducted on the fruit after storage for 1, 5, and 10 days. Storage temperature significantly impacted many of the fruit characteristics evaluated. Melons stored at 10° C had less microbial growth and higher sensory scores compared to the melons stored at 21° C. For tomatoes, many of the sensory and nutritional qualities were higher when stored at 21° C, even at 10 days storage. Use of a CaCl 2 dip treatment positively influenced (p<0.05) sensory scores for melons (appearance, texture, and overall acceptability) and tomatoes (flavor and overall acceptability). Overall, CaCl2 did not affect the fruits' antioxidant contents. When storing organic melons at 21° C, the CaCl 2-dipped melons had lower (p<0.05) Enterobacteriaceae bacterial counts compared to non-dipped melons. Based on this study, a CaCl2 treatment shows promise for increasing some safety and sensory characteristics of fresh melons and tomatoes, especially for produce stored at room temperature (21° C). Additional research should be conducted to further explore the potential of CaCl2 to lessen post-harvest expenses and losses while maximizing the sensory, nutritional, and safety characteristics of fruit.Item Open Access Effects of the postprandial environment on the unfolded protein response(Colorado State University. Libraries, 2009) Pfaffenbach, Kyle, author; Pagliassotti, Michael J., advisorBackground and specific aims. Newly synthesized proteins must undergo post-translational modifications such as folding and glycosylation to become fully functional. The lumen of the endoplasmic reticulum (ER) is a major site of protein folding and processing. The ER can respond to an increase in unfolded proteins (termed "ER stress") by activating the Unfolded Protein Response (UPR), a quality control mechanism which maintains ER homeostasis. Recent studies have demonstrated that the UPR is also involved in the regulation of a diverse array of cellular processes including glucose homeostasis, lipogenesis, and protein synthesis. The liver plays a central role in nutrient metabolism and maintaining glucose homeostasis. Further, in the postprandial state, both lipogenesis and protein synthesis are stimulated in the liver. However, the role of the UPR in the postprandial regulation of these processes has not been studied. Therefore, the first aim of the present study was to examine and characterize the regulation of the UPR in the postprandial state in the liver. One of the main rate limiting steps in protein synthesis is regulated by the mammalian target of rapamycin complex-I (mTORC I). Thus, the second aim of the current study was to examine the role of mTORC1 in the postprandial regulation of the UPR. Methods. Rats in Study 1 were fed a single starch or high sucrose meal and sacrificed either 1 or 7 hours post-feeding period. Plasma glucose and insulin were measured and hepatic tissue was examined for markers of UPR activation. Rats in Study 2 were injected with rapamycin, an inhibitor of mTORC1, prior to meal feeding. Rats were sacrificed 1 or 7 hours post-feeding period and blood and liver tissue were collected for analysis. To examine the role of insulin and glucose in the postprandial activation of the UPR H4IIE liver cells were exposed to varying amounts of glucose and insulin in the presence or absence of rapamycin. Results. Feeding activated select components of the UPR, including spliced X-box binding protein-1 (XBP1) and increased GRP78 and GRP94 mRNA expression. Rapamycin inhibited the postprandial increase of these components. The phosphorylation of eif2-α protein was not increased postprandially in the liver. Data from H4IIE cells demonstrate that insulin in the presence of glucose can activate UPR components in an mTORC1 dependent manner. Conclusion. The current study demonstrates that select components of the UPR are activated in the liver in the postprandial state. This activation appears to be insulin and mTORC1 dependent.Item Open Access Cardiometabolic plasticity and skeletal muscle protein expression in Hispanic and non-Hispanic whites in response to a short-term diet and exercise intervention(Colorado State University. Libraries, 2009) Schmidt, Stacy L., author; Melby, Chris, advisor; Hickey, Matt, advisorThe prevalence rates for type 2 diabetes (T2D) and the metabolic syndrome (MetS) have steadily increased to epidemic proportions over the past few decades, with disproportionately high rates of these health problems in Hispanics. The largest minority group in the United States is Hispanics, with Mexican Americans (MA) comprising the largest and fastest growing portion of the US Hispanic population. Insulin resistance is more prevalent in the MA population compared to other ethnic groups, and appears to precede many of the metabolic abnormalities involved in the progression toward T2D and MetS. Insulin resistance and many factors present in the MetS have been shown to improve following an increase in physical activity and consumption of diets low in saturated fatty acids and high in fiber. The overall objective of this project was to determine the combined effects of an increase in exercise combined with dietary lipid and carbohydrate modification on insulin sensitivity and blood lipids, and to determine if differences in expression of skeletal muscle proteins exist in non-obese, non-diabetic sedentary MA and NHW adults.Item Open Access The effects of moderate exercise on measures of postprandial lipemia(Colorado State University. Libraries, 2009) Cox-York, Kimberly Ann, author; Horton, Tracy J., advisor; Pagliassotti, Michael, advisorBackground. Elevated triglycerides (TG) and small lipid particle size are risk factors for cardiovascular disease (CVD), which are typically assessed after an overnight fast. Most individuals spend the day in the postprandial (PP) state, however, which might be more reflective of CVD risk. A single exercise bout has been shown to decrease PP TGs in response to a single, high-fat meal. The current study assessed the effect of a single bout of morning exercise on PP lipids over an entire day with 3 mixed meals of a typical macronutrient composition (34% fat, 15% protein, 51% CHO). Methods. 26 normal weight (NW) subjects and 18 subjects with metabolic syndrome (MetS) were studied. After an overnight fast, subjects exercised (treadmill walking, 60%VO2peak) or rested for 60 min then consumed breakfast, lunch, and dinner, contributing 25%, 35% and 40% of daily energy intake respectively. Fasting blood samples were collected before exercise or rest and continued throughout the day and were analyzed for PP lipids, glucose and insulin. A subset of the plasma samples were separated into triglyceride-rich lipoprotein (TRL) subfractions in which TG and cholesterol were measured. Apolipoprotein (apo) B-100 and B-48 proteins were measured in the medium-sized subfraction (TRL2) to assess particle origin, size and composition. Postprandial responses were analyzed via ANOVA (SPSS 16.0). Results. Overall, exercise had no effect on PPTG. With exercise, total apoB IAUC decreased 20% in the whole group, and total cholesterol IAUC decreased 30% in the NW group. MetS subjects maintained significantly higher TG than NW subjects over the day (p<0.001). PPTG in MetS women declined mid-day, and remained low for the rest of the study day. In MetS men, however, PPTG rose consistently from breakfast, and then leveled out post-lunch and remained high. TRL particle size (TG:apoB ratio) was 30% lower in MetS women than MetS men. TRL2 apoB-100 and B-48 were twice as high in MetS as in NW subjects, resulting in significantly smaller particles in the MetS group (p=0.01). Conclusions. Although exercise did not have a significant effect on PPTG, there were other potentially cardio-protective effects on apoB and cholesterol levels.Item Open Access Food as a visual cue: an analysis of perception, behavior and neural activity(Colorado State University. Libraries, 2009) Burger, Kyle S., author; Johnson, Susan L., advisor; Pagliassotti, Mike, advisorIntake regulation is a complex process impacted by a number of factors such as homeostatic, environmental and hedonic influences. Previous models of intake regulation tend to not take into account the large influence that the environment (e.g., visual cues) has on eating behavior. Little work has been completed that evaluates the interrelationship of environment, psychology and physiology relations' to eating behavior. A new model of intake regulation, including aspects of environment, psychology and physiology serves as the basis for this investigation. A series of three studies were completed. The first study evaluated the effect of visual cues i.e., portion size and blindfolding on energy intake. The second study used a computer program to assess individuals' subjective hedonic ratings (i.e., liking and wanting) of food images. The third study used neuroimaging to evaluate individuals' brain activity in response to food images. The first study demonstrated that energy intake increased 26% and bite size increased 2.3g/bite in response to presentation to a large portion. This was driven by overweight individuals. No portion by blindfolding interaction was found, indicating that blindfolding did not attenuate the portion size effect. It was observed in the second study that ratings for wanting were consistently higher that ratings for liking and fruits were the highest rated foods. In addition, in a fed state, overweight individuals rated large portions of food higher smaller portions of food for wanting, but not liking. Ratings for liking were related to activation of the posterior cingulate (decision making). It was also observed that dietary restraint was related to suppression of activity in the anterior cingulate (food reward). An increase in portion size appears to impact overweight individuals' energy intake (which occurs via changes in bite size) and ratings for wanting. A positive energy state could affect ratings for wanting but not liking. This decrease in wanting could be interpreted as dietary restraint which might function by decreasing brain activity in food reward related regions. Studying a comprehensive model including of intake environment, perception, behavior and physiology provides valuable insight to the interrelationship of all of eating behavior.Item Open Access A single session of moderate exercise, without energy deficit, may reduce svcam-1 concentrations in young, sedentary females(Colorado State University. Libraries, 2010) Krause, Molly Annamarie, author; Melby, Christopher, advisor; Hickey, Matthew, committee member; Nelson, Tracy, committee memberPurpose: Cardiovascular disease remains the number one cause of death within the United States and globally [1, 2]. Postprandial lipemia and vascular adhesion molecules are becoming more widely recognized as biomedical makers associated with increased risk of developing CVD [3-5]. It has been well established that moderate exercise can improve some aspects of postprandial metabolism such as decreased triglycerides and improved insulin sensitivity [6]. However, there is limited data regarding the effect of prior moderate exercise on attenuating postprandial response specific to adhesion molecules [7, 8]. The purpose of this study was to determine the effects of a single bout of acute exercise, with energy replacement, on plasma soluble vascular adhesion molecule-1 (sVCAM-1), a marker of endothelial dysfunction, measured during fasting and in response to a high-fat, high-carbohydrate meal in young, non-obese, sedentary females. Methods: Eight, non-obese (x body mass index=24.6 kg/m2), habitually sedentary females (x age= 19.6 y) participated in this study. Following preliminary testing, each subject completed two trials in random order: 1) Exercise (Ex) 2) Non-exercise (Non-Ex). Each trial took place over 2 days. On the evening of day 1, subjects either rested (Non-Ex) or completed a cycle ergometer exercise bout at 65% peak heart rate, eliciting net exercise energy expenditure of ~285kcalories. On the morning of day 2 of each trial a fasting venous blood sample was drawn for measurement of sVCAM-1, followed by the consumption of a high-fat, high-sugar meal by each participant. Postprandial venous blood samples were then taken over at 2, 4, and 6 hours following meal ingestion for measurement plasma sVCAM-1 concentrations. Results: There was no significant treatment by time interaction on sVCAM-1 concentrations, nor was there a significant main effect of time. There was a significant condition effect on circulating soluble VCAM-1 concentrations such that concentrations were lower before and following the high-fat, high-sugar meal challenge for the EX compare to the NonEx condition. Conclusions: Results from the current study suggest that a single session of moderate exercise, without an energy deficit, may reduce sVCAM-1 concentrations in young, sedentary females. However, this finding must be viewed with caution owing to possible issues with thesVCAM-1 measurements, and the assay repeated prior to drawing any conclusions about the effect of acute exercise on circulating sVCAM-1 concentrations measured the morning after exercise.Item Open Access Dissemination and implementation of the Cooking with Kids tasting curriculum(Colorado State University. Libraries, 2010) Diker, Ann, author; Cunningham-Sabo, Leslie Derry, advisor; Anderson, Jennifer, advisor; Baker, Susan S., committee member; Kaminski, Karen, committee member; Most, David E., committee memberNumerous school health education programs, including nutrition education curricula have been developed. To improve dissemination and implementation of nutrition education curricula in schools, research is needed to identify and measure factors that facilitate and hinder the dissemination and implementation processes. Therefore, this study was conducted to identify strategies and practices that aided dissemination, adoption, and implementation of the Cooking with Kids (CWK) tasting curriculum by paraprofessional Nutrition Educators (NE). The study used a mixed methods time-series design. Formative assessment data were collected from two web-based surveys (n=313) and 27 interviews. The assessment results and constructs of Diffusion of Innovations and Social Cognitive Theory were used to develop a three-hour training introducing CWK to NE and their supervisors. Intervention data were collected from paraprofessional NE (n=49) and their supervisors (n=21) using a series of surveys, interviews, and implementation reports. Quantitative data analysis included descriptive analysis, factor analysis, analysis of variance, paired samples t-tests, correlations, and multiple regression. Qualitative data were analyzed for themes. Formative assessment revealed active participation, lesson observation, and pilot-testing as essential features of effective paraprofessional NE training. From pre- to post-training, NE and supervisors reported improved knowledge about teaching the curriculum (t=5.12, p<0.01 and t=8.31, p<0.01, respectively), confidence (t=3.93, p<0.01 and t=3.62, p<0.01, respectively), motivation (t=3.71, p<0.01 and t=2.63, p<0.05, respectively), and information (t=7.17, p<0.01 and t=4.15, p<0.01, respectively) to teach the curriculum. Gains in NE knowledge, confidence, motivation, and communication skills were sustained eight months post-training. Gains in supervisor knowledge were sustained eight months post-training. Supervisor motivation to use CWK returned to pre-training levels, which were relatively high to begin with so there was limited room for improvement. Although supervisor confidence was higher at eight months post-training, it was not statistically different from pre-training levels. These results may be attributed to the fact that supervisors did not teach the tasting lessons. High levels of curriculum adoption and implementation by NE were attributed to strong implementation expectations, experiential and observational learning training elements, and perceived curriculum compatibility with existing programming. Environmental factors such as time constraints, personnel turnover and scheduling conflicts proved challenging. Study results underscore the importance of combining theory and formative assessment for successful development and implementation of training and, in turn, curriculum implementation. In addition, results indicate that perceived simplicity, compatibility, and trialability are important attributes that should be maximized when introducing new curricula to potential adopters.Item Open Access Listeria control and safe food training for dietary managers(Colorado State University. Libraries, 2010) Thigeel, Hanaa Abid, author; Kendall, Patricia A. (Patricia Ann), 1947-, advisor; Sofos, John Nikolaos, committee member; Bunning, Marisa, committee memberElderly individuals are a growing sector in the U.S. population. With that increase, the need for long-term care facilities (LTCF) is growing as well. It is estimated that 5% of individuals age 65 or older and 20% of individuals age 85 or older live in long-term care facilities. Due to aging, the immune system of the elderly becomes weak, which increases the vulnerability to foodborne illnesses. Other factors associated with aging like chronic disease, dementia, lack of physical activity and entering nursing homes, can also contribute to the increased susceptibility to foodborne diseases. For these reasons, caregivers of the elderly, including dietary managers who serve food to the elderly, should be aware of factors that can increase the likelihood of contracting infection. Listeria monocytogenes is a particularly important foodborne pathogen that can cause severe illnesses or even deaths in populations at higher risk for foodborne illness, including the elderly. "Listeria Control and Safe Food Training for Dietary Manager" was an on-line course developed to provide important information about this pathogen and suggested control measures. The training module targeted Dietary Managers and Registered Dietitians who work in LTCF. The module consisted of three segments and was 47 minutes long. The module included PowerPoint® slides, recorded audio, written scripts and reference links. Pre and post questionnaires were used to measure the course outcomes along with course evaluation items. Multiple-choice knowledge questions were developed and evaluated for reliability, content validity and difficulty by module developers. Of 20 questions initially developed from the course content and tested for reliability, 13 questions were selected as final questions. Participant recruitment for the module pilot testing was conducted through winter 2010. Participants were recruited via state Dietary Manager Associations and state associations for Registered Dietitians and Dietetic Technicians. Emails and advertisement fliers were used for recruiting efforts. Of 211 participants who showed interest in the module, 143 participants were able to complete both the pre and post knowledge questionnaires. Participants who completed the course received one continuing education credit from their professional organization. The module knowledge scores achieved significant increase (P<0.0001) from pre to post-questionnaire. The knowledge score overall increased from 65.7% correct pre to 88.7% post. The course evaluation showed that more than 90% agreed or strongly agreed that they gained new and useful information from the course and planned to use the information in training others. They also found the web module a convenient way to earn continuing education credits. Feedback gained from course pilot test and evaluation will be considered as a helpful tool in making improvements to future on-line courses.Item Open Access Microbial quality of mixed salad greens and selected fresh and dried herbs(Colorado State University. Libraries, 2010) Woo, Daniel Lee, author; Bunning, Marisa, advisor; Goodridge, Larry, committee member; Stone, Martha, committee memberDirect marketing has been growing in the Western U.S., with 2007 sales of direct-marketed agricultural products totaling nearly $142.6 million in Colorado, New Mexico, Oregon, Idaho, Nevada and Washington-more than twice the 1997 sales level for the region. In addition, the number of farms engaging in direct sales to consumers grew by more than 20% to 18,274 in 2007. With increasing foodborne outbreaks linked to produce consumption, more research is needed to fill in the gaps of knowledge on the microbiological quality of leafy salad greens. Limited research has been conducted on the microbial safety and quality of farmers' market leafy salad greens. This study surveyed the microbial quality of salad greens from Larimer County farmers' markets in conjunction with salad mixes from a local supermarket. Leafy salad greens were obtained weekly for a period of four weeks from September to October, 2009, from both farmers' markets and supermarkets. Total aerobic and coliform counts were assessed within 48 hours of obtaining the samples via plating onto Petrifilm plates, then following one week of storage at refrigeration temperatures to observe changes in the microbial load. In addition, handling methods and temperatures were also recorded. Gloves and tongs were not used by vendors when handling salad greens. The vendors surveyed also lacked adequate refrigeration or ice for holding salad greens. Farmers' market salad greens were lower than supermarket salad greens in terms of initial aerobic plate counts. Both farmers' market and supermarket salad greens had no detectable levels of Escherichia coli and low levels of coliforms. After 1 week of storage, aerobic counts were higher in all samples (P<0.05). Coliform counts tended to decrease in all samples but no significant differences were observed (P>0.05). The results reiterate the need for consumers to thoroughly wash their salad greens. Further research should be conducted to assess the microbial quality o~ other produce at local farmers' markets. Herbs are often used in cooking to add aroma and flavor to foods. Consumers may choose to dry herbs from their garden or purchased from the market. Herbs, like other agricultural produce, may be exposed to a wide range of potential microbial contamination. There is currently little research on safe drying practices of herbs at home. Microwaving herbs is a potentially popular and time-saving approach for drying herbs at home. This research project investigated the impact of three drying methods (microwave, dehydrator, and conventional air drying) for improving the microbial quality of dried parsley and cilantro. Herb samples were obtained weekly from a local supermarket for a 2 month period from January to March, 2010. Standard guidelines from Oregon State University Extension service were followed for microwave drying of herbs. The manufacturer's drying temperatures/times were used for drying herbs in a dehydrator. Herbs were also air-dried for 1 week. Microbial testing was performed using plating onto 3M Petrifilm and when counts were below the detection limit, via the Most Probable Number (MPN) method. Microwave drying provided the greatest reduction in aerobic counts of bacteria in herbs. All drying methods reduced coliform counts to undetectable amounts; however, the determination of the effectiveness of each drying method in comparison with others for reducing the coliform count was complicated by the low initial load of coliforms in herbs used in the study.Item Open Access Assessing the attitudes of hospitality students towards the use of a classroom response system (CRS)(Colorado State University. Libraries, 2010) Milholland, Eric Stanley, author; Miller, Jeff, advisor; Martin Gould, Susan, advisor; Hogler, Raymond, committee memberA Classroom Response System (CRS) is a technology instructors can use to promote active learning. Researchers have shown a number of benefits of CRS use, including anonymous student response, better attendance, increased peer instruction, higher test scores, better grades, and the ability to use contingent teaching methods. Compared to traditional methods, contingent teaching allows instructors to gain real-time understanding of what students know and comprehend. Instructors then can use CRS based feedback to employ learner-paced instruction. Previous researchers focused on CRS use in disciplines like math and physics. A literature review did not locate any previous studies about using CRS in hospitality education. Regardless of the course studied, researchers found CRS was most effective when used as a tool to reinforce sound pedagogy. This study investigated the attitudes of hospitality students regarding the technology. The study was conducted over a three semester period, and was comprised of hospitality students (n=l 17) in an introductory food science course in which a CRS was used. Students responded to additional statements on standard course evaluation surveys. Students also wrote comments about their CRS experience in this class. Survey responses indicated students felt CRS encouraged discussion and participation, helped reinforce course concepts, and increased class enjoyment. Additionally, students suggested using CRS in more of their hospitality courses and in more courses university-wide. Students written responses indicated similar opinions as the surveys. Students indicated CRS helped them understand concepts, engage in discussion, and motivated them to attend. Others said using the device was fun and would recommend it to other students and for other classes. The results showed hospitality students have an overall positive attitude regarding CRS. This research indicated hospitality educators may want to use this technology to enhance instruction. As future versions of the technology evolve to become even more interactive, additional research should be conducted to see how CRS use will change in the future.Item Open Access Rapid detection of viable escherichia coli O157:H7 by antimicrobial incorporated multi-angle light scattering spectroscopy(Colorado State University. Libraries, 2010) León, Juan Carlos, author; Goodridge, Lawrence D., advisor; Bunning, Marisa, advisor; Nightingale, Kendra K., committee memberEscherichia coli 0157:H7 continues to cause outbreaks of produce-associated foodborne illness. Contaminated water has been shown to be a vehicle for transfer of E. coli 0157:H7 to leafy greens during irrigation. Timely detection of this pathogen in irrigation water can prevent contamination of the final product. Current detection methods which are culture-based can be labor intensive and require several days to produce results. There is a need for development of rapid detection methods, which can detect E. coli 0157:H7 in irrigation water. These methods have to be sensitive, robust and ideally should be able to differentiate between viable and non-viable microorganisms. Multi-angle light scattering spectroscopy (MAES) is a powerful technique that has been applied to qualitatively and quantitatively distinguish internal structural changes in cells upon perturbation by chemical/biological agents. We hypothesized that combining bacteriophage (phage) infection, which occurs only in viable bacterial cells, with MAES would allow for detection of the target bacteria and distinguish between viable and nonviable bacterial cells. The objective o f this study was to use E. co//-specific bacteriophages in conjunction with immunomagnetic separation and MAES to develop an assay for rapid detection of viable E. coli 0157:H7 in irrigation water. We have termed this new method Antimicrobial Incorporated Multi-angle Light Scattering (ANIMALS) to highlight the combination of a specific antimicrobial agent (phages) with the multi-angle light scattering technique to form a sensitive, rapid and specific assay for detection of E. coli 0157;H7. E. coli 0157:H7 and Salmonella Typhimurium strains were diluted in lambda buffer to form concentrations of 10*^ to lO"^ CFU/ml and 10*, respectively. The samples were subjected to immunomagnetic separation (IMS) using E. coli 0157-specific IMS beads. Following IMS, the beads (and attached bacteria) were resuspended in 1 ml of tryptic soy broth (TSB) and one half (500 pi) of each sample was added to 10 mis of TSB that contained 1 ml of phage ARl (lO'** PFU/ml). The other half of the samples were added to TSB that did not contain phage AR l, but contained 1 ml of lambda buffer (to maintain constant volume), and these samples served as a reference. The samples were incubated at 37° C, with shaking, for 15 hours. Following incubation, 100 pi aliquots were removed from each sample, and separately assayed using a SpectraPoint light scattering spectrometer (Spectra Digital Corp., Toronto, Ontario, Canada). E. coli 0157:H7 was detected in 100% of pure culture samples in TSB containing various concentration (10*^ to 10^) of the bacterium within 15 hours. An algorithm was developed to evaluate the area under the curve of each spectra. When compared to the light scattering spectra of the non-phage treated reference, the spectra o f phage infected E. coli 0157:H7 cells differed markedly. In contrast, the spectra of samples that contained Salmonella Typhimurium and the negative controls (containing no cells) were almost identical, because phage ARl does not infect Salmonella Typhimurim and there was no growth in the negative control samples, respectively. Using this method, E. coli 0157:H7 could be detected following 15 hours of incubation in samples spiked at an initial concentration of 10** CFU/ml. The sensitivity and specificity of the ANIMALS assay was determined using environmental water samples. River water samples were artificially contaminated with a 3-strain cocktail of E. coli 0157:H7, followed by IMS and incubation in TSB supplemented with 20 mg/ml novobiocin at 42° C. MALS measurements were taken at 4, 6, 8 and 10 hours. The means and standard deviations of the ratios o f the differences between the test and reference spectra for the four concentrations (10‘^ to 10^ CFU/ml) o f E. coli 0157;H7 were analyzed as well as for negative controls (samples o f river water that were not inoculated with E. coli 0157:H7). One concentration (10^ CFU/ml) of E. coli 0157:H7 was detected consistently after only 6 hours of enrichment. E. coli 0157:1-17 was consistently detected at concentrations from 10‘ to 10^ CFU/ml in spiked river water within 8 hours. All concentrations (10° to 10^ CFU/ml) were detected after 10 hours of enrichment. The presence of the pathogen in positive river water samples was confirmed by using lateral flow devices specific for E. coli 0157:H7. The negative controls resulted in negative readings. Additionally, reservoir water samples were prepared similarly to river water samples and MALS measurements were taken at 4, 6, 8 and 10 hours. The test and reference spectra for the four concentrations (10° to 10^ CFU/ml) of E. coli 0157:H7 were analyzed as well as for negative controls (samples o f reservoir water that were not inoculated with E. coli 0157:H7). Similar results to experiments on river water were obtained with 10^ concentrations of E. coli 0157:H7 detected consistently at 6 hours. This demonstrated that the ANIMALS assay worked consistently across water samples with different physical and chemical characteristics. Regardless, E. coli 0157:H7 was consistently detected in 100% of concentrations (10 to 10 CFU/ml) within 8 hours even against background levels of bacteria as high as 10^ CFU/ml. Lateral flow devices specific for E. coli 0157:H7 confirmed the presence of the pathogen in positive reservoir water samples. The negative controls resulted in negative readings. These results demonstrate the ability of ANIMALS to rapidly and sensitively detect the presence and viability of E. coli 0157:H7 following phage infection. This method has the potential to allow for rapid detection o f viable E. coli 0157:H7 in irrigation water against a high background o f non-target microorganisms if coupled with selective enrichment.Item Open Access A one-week controlled diet and exercise intervention significantly improves insulin sensitivity without changes in plasma adiponectin concentrations in young non-Hispanic white and Mexican American adults(Colorado State University. Libraries, 2010) Botero, Maria Fernanda, author; Melby, Chris, advisor; Allen, Kenneth, committee member; Hickey, Matthew, committee memberBackground: Hypoadiponectinemia (low levels of adiponectin in blood) has been linked to insulin resistance and type 2 diabetes (T2D). In the USA, the prevalence of these latter two conditions is higher in Mexican Americans (MA) when compared to Non-Hispanic Whites (NHW). Variations in plasma adiponectin concentrations may partially contribute to differences in insulin resistance and T2D prevalence rates between adults of these two ethnic groups. Also, plasma adiponectin concentrations in MA and NHW adults may respond differently to a diet and exercise intervention. Objectives: 1. To determine whether or not pre-intervention fasting plasma adiponectin concentrations differ between sedentary, non-obese MA and NHW adults; 2. To determine if a combined one-week exercise and diet intervention (controlled low-saturated fat, low-sugar, high-fiber diet) improves both plasma adiponectin concentrations and insulin sensitivity in both NHW and MA adults; 3. To determine if changes in insulin sensitivity are associated with changes in circulating adiponectin concentrations. Methods: During the pre-study phase, volunteers underwent all initial screening tests. Eligible participants [n= 37; (20 NHW; 9 males, 11 females and 17 MA; 4 males, 13 females aged 18-40 years), fasting blood glucose < 126 mg/dl, blood pressure < 140/90 mm Hg, BMI < 30 kg/m2] continued with a 7-day baseline period, in which they were asked to maintain their regular food intake and their usual low level of exercise. A 3-hour intra-venous glucose tolerance test (IVGTT) for the measurement of insulin sensitivity was performed at the end of this period, as well as measurement of fasting plasma adiponectin. The intervention phase started immediately the day after and ended 7 days later. Subjects consumed a diet that was rich in vegetables, fruits, dietary fiber, and lean proteins and low in saturated fat and refined carbohydrates. Study investigators prepared all foods which were provided to participants. Subjects also exercised on a stationary cycle ergometer for 6 out of the 7 days of the intervention (40-45min/session at 65%V02 max). At the end of the intervention, 16-17 hours after the last exercise bout, plasma adiponectin was again measured and another IVGTT was performed. Dependent variables were analyzed using a 2 X 2 repeated measures ANOVA. Results: Insulin action, determined by the 3-h insulin area under the curve (IAUC) in response to glucose infusion, improved significantly (p<0.05) in response to the intervention (IAUC µU*min/L pre, post: MA = 2297, 1635; NHW = 1794, 1210). At baseline, plasma adiponectin levels were not significantly different between NHW and MA adults (NHW= 11.42 mµ/ml, MA= 11.17 mµ/ml) and there were no significant changes in adiponectin in response to the intervention in either group. Conclusion: A one-week diet and exercise intervention significantly improved insulin action in both MA and NHW adults, but changes in circulating adiponectin were not observed. Thus, the improvement in insulin sensitivity in response to a short-term diet/exercise intervention was disassociated from any changes in circulating adiponectin.Item Open Access Mini-program ENERGY Cortez: obesity and type 2 diabetes prevention through science enrichment for elementary school children in rural southwestern Colorado(Colorado State University. Libraries, 2010) Culbertson, Diana Lynn, author; Campfield, Leroy Arthur, advisor; Melby, Christopher L., committee member; MacPhee, David, committee memberTo view the abstract, please see the full text of the document.Item Open Access The effect of CSA membership on fruit and vegetable intake(Colorado State University. Libraries, 2011) Hedden, Jessica L., author; Auld, Garry, advisor; Bunning, Marisa, committee member; Stonaker, Frank, committee memberObjective: Increased fruit and vegetable intake has been associated with decreased BMI and disease rates (Ford & Mokdad, 2001; Lin & Morrison, 2002; Liu, 2000; Newby, et al., 2003; Riboli & Norat, 2003). Multiple barriers inhibit fruit and vegetable consumption, including the availability in the U.S. (Pollard, et al., 2002). Currently, there are many forms of alternative food networks (AFNs) such as farmers markets, community gardens and community supported agriculture (CSAs) providing local, seasonal produce to consumers, attempting to address availability and provide other outlets for fresh produce. This study examines the influences that CSA membership may have on fruit and vegetable intake. Methods and Materials: Sixty-one participants were recruited from an average-sized CSA (<100 members; CSU), a large CSA (>2000 members; GFF), and non-CSA members (NON- as a control group). Three, 24-hour dietary recalls were collected by phone to estimate the produce components of each participant's diet over 6 months during the 2010 CSA season. Each diet was quantified based on the amount and variety of fruit, vegetables, total fruit and vegetables, and leafy greens. Results: The groups were very similar in fruit and vegetable consumption at baseline. At the peak of CSA season (T2), GFF participants were consuming more vegetables (2.96 [0.26]) and more total fruits and vegetables (4.45 [0.40]) than NON participants (2.16 [0.29], p<0.1; 3.38 [0.45] p<0.1, respectively). Both CSU and GFF participants had an increased variety of vegetables over NON participants (p<0.01 and p<0.001, respectively) and participants from both CSAs had higher total variety (p<0.01) at Time 2. Conclusions/Implications: From this study, variety was the major dietary difference in produce intake between both CSA groups and the control group. Demographic characteristics of participants were similar, indicating that the observed changes were likely a true relationship. A diet with increased variety of fruits and vegetables has been associated with increased health benefits, having the potential to reduce disease rates (Wirt & Collins, 2009). More studies need to be conducted examining larger study populations, the potential effect CSAs may have on low-income populations, and other forms of alternative food networks, such as farmers markets or community gardens.Item Open Access Assessment of airborne microorganisms in a craft brewery(Colorado State University. Libraries, 2011) Miller, Amanda Leah, author; Bunning, Marisa, advisor; Stone, Martha, committee member; Hyatt, Doreene, committee memberAlthough pathogenic bacteria have little chance of surviving in beer due to its intrinsic antimicrobial hurdles, there are other microorganisms capable of surviving and spoiling beer. The quality of all food products including beer are not only affected by the integrity of the raw materials, and cleanliness of the equipment and packaging materials, but also by the purity of the environmental air surrounding the processing area. The purpose of this project was to examine the environmental microbial air quality within various areas of a craft brewery with special emphasis on potential beer spoiling bacteria. First, samples inside the brewery and samples outside the brewery were collected to establish a baseline of data, identify areas of concern, and to examine the effect of seasonality. Those areas of concern then were sampled more often and also were sampled based on the risk of product contamination. The canning line within the brewery was identified as a specific area of concern. Bottling and canning lines in breweries often are considered non-closed production equipment and have the ability to become contaminated from outside sources including the environment. The air was sampled 307 times over a period of 22 months using an automated impaction sieve sampler pulling 80 liters of air. Samples were plated both aerobically and anaerobically. The aerobic plates were used for a general cleanliness of the area while the anaerobic plates were included to examine for beer spoiling organisms. The standard (specification limit) used for the indication of a contaminated area was a plate with 40 colony forming units (CFU) or more per 80 liters of air sampled. The results of this study revealed that testing for airborne microorganisms is highly recommended in the craft brewing industry due to the potential for the impurity of the environmental air surrounding the processing area. Seasonality had an effect on total number of aerobic airborne microorganisms with the spring months being approximately five times higher than other months. The canning line in the brewery was found to be contaminated with beer spoiling bacteria on average 75% of the time. Critical areas in the brewery, such as the bottling and canning lines, should be routinely tested for airborne microorganisms as they could lead to final product contamination. Routine microbial environmental air testing is a good indicator of overall brewery cleanliness.Item Open Access Assessing the outcomes and acceptability of healthy lifestyles for Youth Corps members: phase 2 of a multi-phase project(Colorado State University. Libraries, 2011) Kissane, Katharine Roseanne, author; Anderson, Jennifer, advisor; Trumbo, Craig W., committee member; Bellows, Laura Leigh, committee memberBackground: Obesity is a costly condition that can reduce quality of life and increase the risk of several chronic diseases. Obesity has a multi-factorial etiology, which includes genetic, behavioral, and environmental factors (Baranowski 2000). Such a complex disease needs a complex solution such as changing public policy and the environment. In addition, people must be given knowledge and self-efficacy to live healthy lifestyles. The obesity epidemic is not limited to adults. Childhood obesity is a growing problem. In 1980, 6.5% of children aged 12-19 years were obese and this number increased statistically to 19.6% in 2008 (CDC 2010). According to the 2007 National Survey of Childhood Health the obesity rate in Colorado for youth ages 10-17 is 14.2%. Children in Colorado are ranked 29th out of the 50 states for obesity (Trust for America's Health 2010). The committee on prevention of obesity in children and youth encourages the evaluation of interventions that focus on preventing an increase in obesity prevalence, improving dietary behaviors, increasing physical activity levels, and reducing sedentary behaviors (Koplan et al 2005). There are several obesity prevention and intervention programs targeting youth, however, most of these efforts have been school-based or limited to school-aged children. The Youth Conservation Corps is a population not reached though these efforts. Traditionally, many of the youth employed by the Youth Corps have been low-income, at-risk, and ethnic minorities. There are currently no prevention programs targeting this audience and there have been no previous efforts addressing the health outcome of Youth Conservation Corps members. Objective: The first objective of this project (phase 2) was to revise the Healthy Lifestyle for Youth Corps Members curriculum based upon the pilot test with 13 corps members of phase 1 of the project. The second objective for phase 2 of this project was to implement the Healthy Lifestyles for Youth Corps Members and analyze changes in knowledge, attitudes, and behaviors regarding healthy lifestyles. Methods: Revisions to the curriculum were made based on the data collected during the first phase of the project and from suggestions made by researchers at Colorado State University and the Colorado Youth Corps Association. Data used in assessing changes in knowledge, attitudes, and behavior was collected using a survey that was tested for validity and reliability prior to implementation. In addition, the acceptability of the program was assessed by feedback from the corps members provided via the post-survey and crew leaders' instructor notes pages, which were located at the end of each unit specifically for crew leaders to fill out and offer feedback. Implementation and control group sites included Western Colorado Conservation Corps, Mile High Youth Conservation Corps, Larimer County Youth Conservation Corps, Southwest Conservation Corps -Four Corners and Southwest conservation Corps- Las Valles. Results: One hundred corps members in Colorado completed the program, 58 from the implementation group and 42 from the control group. The average age of all the participants was 20 years. When testing for knowledge only two questions had significant results. Many of the knowledge questions had a ceiling effect, as the corps members already knew the answer leaving no room for improvement. In addition, many of the corps members were already engaging in healthy lifestyle behaviors prior to the implementation of the Healthy Lifestyles Curriculum. Feedback from the crew leaders and corps members suggested that the curriculum was too basic and they suggested that the curriculum should contain more in depth information. However, there were corps members who enjoyed the curriculum and the younger corps members generally rated the curriculum as more acceptable. Conclusions: The results of this study suggest that this sample of Colorado Youth Corps members in this study were not representative of all Colorado Youth Corps. The average age of participants in 2009 was 18 years and in our study, the average age was 20 years. In addition, in 2009 there was more ethnic diversity than the sample in phase 2. Many corps members in this study already had the knowledge about living healthy lifestyles. Changes to the curriculum could include combining units 2 and 3 and units 4 and 5. In addition, incorporating more in depth information could enhance the effectiveness of this curriculum in the future.Item Open Access Survival and inactivation of Listeria monocytogenes biofilms on food contact surfaces using commercially available and household compounds(Colorado State University. Libraries, 2011) Parikh, Sachi Jayant, author; Kendall, Patricia A. (Patricia Ann), 1947-, advisor; Stone, Martha B., committee member; Sofos, John Nikolaos, committee memberTo view the abstract, please see the full text of the document.