Doctor of Philosophy / Department of Human Nutrition / Koushik Adhikari / Coffee is the most consumed beverage after water and the second widely traded commodity after crude oil. In the past decade or so the market for coffee has exploded. It is no longer competitive for the coffee industry to offer consumers just a ‘good’ cup of coffee. Coffee is mainly consumed for enjoyment and offers consumers the desirable emotional experience. Currently not much work has been done to capture the emotion experiences elicited by coffee drinking, which led to our objective: to identify and assess the feelings that are stimulated by the coffee drinking experience through the development of an emotion lexicon. In the first part of the study, focus groups were utilized to generate and fine-tune a list of emotions that occur during the coffee drinking experience. The list of terms was further refined by check-all-that-apply method, resulting in 86 emotions, which included 39 terms from a recently published emotion lexicon for food. In the second part of the study, this lexicon of 86 emotions was used to evaluate six coffee samples of various origins and degrees of roasting with 94 consumers. The emotion intensities before and during drinking were assessed. Consumers were clustered into six clusters based on the acceptability scores, and the appropriate emotions for distinguishing the coffee samples were determined by Stepwise Regression Analysis, which resulted in 44 emotions. Emotion maps for each consumer cluster constructed using Principal Components Analysis revealed that each sample generated distinctive emotional responses, which varied across each cluster. The last part focused on identifying the sensory drivers of emotions to understand the consumer’s perceptions because emotional and sensory experiences determine acceptability and consumption of coffee. Two separate highly-trained panels (a general panel and a coffee panel) performed descriptive analysis of the six coffee samples. After comparing the two panels, the coffee-specific panel data was used to identify the sensory attributes that might be responsible for eliciting certain emotions in the consumers. For instance, darker roasts seem to elicit positive-high energy emotions. Overall, this study is a stepping stone for more in-depth product-specific emotion studies in future.

Master of Science / Food Science Institute / J. Scott Smith / Heterocyclic amines (HCAs) are a class of toxicological compounds that can be formed during heating of precursors, amino acids, creatinine, creatine, and sugars at high temperature cooking of muscle products. These potent mutagens are suspected to play a role in human cancers. The objective of this study was to investigate a practical method to reduce the amount of HCAs through marinating of beef steaks. We were interested in the potential health benefits of natural extracts containing polyphenols present in commercial marinades. HCAs were compared in marinated and unmarinated steaks. Four common HCAs were investigated: 2-amino-3,8- dimethyl-imidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenyl-imidazo[4,5- b]pyridine (PhIP), 1-methyl-9H-pyrido[4,3-b]-indol (harman), and 9H-pyrido[4,3-b]-indol (norharman). Steaks were marinated for one hour and grilled at 400 °F for 5 minutes at each side. Meat samples were extracted by solid phase extraction (SPE) and analysis with HPLC showed the significant decrease (p < 0.05) of sum of polar and nonpolar HCAs by 71% compared to untreated steaks. For confirmation of spices potency on reduction of HCA formation, the same experiment was applied to meat with the base of commercial marinade powders excluding the herbs and spices. Lesser reduction of HCAs were shown and in some cases no significant reduction occurred. HPLC analysis showed presence of considerable amount of natural phenolic antioxidants of carnosic acid, carnosol, and rosmarinic acid, which can be related to the reduction effects of HCA formation in commercial marinades. These results revealed that marinating meats before grilling with various spices/herbs containing antioxidants may reduce formation of mutagenic /carcinogenic HCAs markedly.

The effects of dietary saturated versus polyunsaturated fat (7.5%; w/w) on sterol balance and lipoprotein metabolism were studied in guinea pigs. The polyunsaturated diet significantly reduced plasma cholesterol and triglyceride levels by 34% and 40%, respectively. Polyunsaturated dietary fat significantly reduced the percentage of cholesteryl ester in low density lipoprotein (LDL) while the relative proportion of LDL-phospholipids was increased. The ratio of LDL surface to core components in the polyunsaturated fed animals was significantly higher (P .02). Dietary fat quality had no effect on either sterol balance or hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase activity. Hepatic free and esterfield cholesterol levels were significantly higher in the polyunsaturated fat fed group (P .01). Feeding polyunsaturated fat caused a significant (1.9-fold) increase in hepatic membrane LDL (apo B/E) receptor binding. The data indicate that the hypocholesterolemic effect of polyunsaturated fat is not attributable to changes in cholesterol metabolism but rather to a redistribution of plasma cholesterol to tissues due to increased tissue LDL receptor binding.

Toxic dinoflagellate Prorocentrum concavum cells (DC) implicated in ciguatera poisoning were lyophilized and mixed with a standard fish food and fed to Domino damsel fish (Dascyllus trimaculatus). Damsel fish fed 50/50-SC/DC and 100% DC diets exhibited physical and behavioral changes as well as death. Feed refusal was apparent among the fish fed 100% DC diet. Toxicity of the control group could be attributed to previous exposure of the fish to other polyether compounds in its natural habitat or even other chemicals. Fish extracts of both control and treatment groups were toxic when tested on the Stick-enzyme immunoassay for ciguatoxin. Okadaic acid was detected in P. concavum, but no okadaic acid was found in any of the fish tissue extracts. Further studies are needed to determine the transfer of toxin to the fish through diet before any conclusion is made.

This study was designed to investigate the growth of Streptomyces griseus and Streptomyces odorifer, their production of and the distribution of musty odor compounds in white potato and cornmeal bread. Total plate count and actinomycetes /cm('2) where determined before and after storage for 3 or 5 days at 30 (+OR-) 3(DEGREES)C. A sensory panel was trained to identify musty odor. Musty odor compounds were extracted with organic solvents prior to analysis by gas chromatography and mass spectrometry. / There was a significant difference (p < 0.01) in total plate count before and after storage of both the treated and untreated potato and bread samples. However, there was no significant difference in total plate count of the samples treated with S. griseus compared with those treated with S. odorifer. Inner layers exhibited significantly lower growth when examined for total plate count and actinomycetes in all samples. Actinomycetes represented only 11-14% of the total plate count after storage. / Retention times for geosmin and 2-methyl-isoborneol were determined by analyzing the gas chromatography and mass spectrometry data. No increase in peak height of geosmin or 2-methyl-isoborneol resulted when the food sample was added to standards. Further analysis of the mass spectra showed geosmin and 2-methyl-isoborneol peaks to be absent from the food sample. These results were the same for both strains in potatoes and bread. It was concluded that the actinomycetes in this study did not produce geosmin or 2-methyl-isoborneol in detectable quantities. / Foods treated with S. griseus or S. odorifer received significantly higher scores (p < 0.05) for musty odor than control samples; however, there was no significant difference in scores between S. griseus and S. odorifer. There was no significant difference in odor between inner layers of treated and control samples of bread or potatoes. The offensive odor that developed on outer layers was believed to be a mixture of musty and other offensive compounds produced by spoilage aerobes. / Source: Dissertation Abstracts International, Volume: 44-12, Section: B, page: 3705. / Thesis (Ph.D.)--The Florida State University, 1983.

The effects of feeding rats a fat which contained approximately 46.6% trans fatty acids (trans fat) on the mutagenic potential of 2-aminofluorene (AF), benzo(a)pyrene (BP), dimethylbenz(a)anthracene (DMBA), and azoxymethane (AOM) were evaluated in the Ames assay. The corresponding control fat (cis fat) had a similar fatty acid composition, consisting only of cis isomers. Since both the cis and trans fats contained approximately 40% saturated fatty acids a comparison was made between these two types of fat and corn oil. All three fats were incorporated into a high fat, 20%, and moderate fat, 5%, diet and fed to male Sprague-Dawley rats for three weeks. / The effects of the level and type of fat on mutagenicity varied with the specific mutagen under investigation. The 20% level of fat whether cis, trans, or corn oil resulted in greater mutagenic activity with BP and AF when compared to the 5% level. At the 5% fat level the results for BP and AF were in conflict. The 5% trans fat resulted in the highest mutagenic response for AF, while the 5% corn oil resulted in the highest mutagenic response for BP. The trans fat produced a higher mutagenic potential at the 5% level with AF than the 5% cis fat, but at the 20% level no difference was found between the cis and trans fats. These findings indicate that not only does the quantity and type of fat alter the mutagenic response found in the Ames/Salmonella microsome assay, but also the effect of the fat in the assay varies with the mutagen tested. / Only with DMBA did type of fat affect the positive and negative outcomes of the assays. DMBA gave a positive response only in the assays using livers from rats fed corn oil diets, with no differences between the 5% and 20% level of corn oil. No positive responses were found with DMBA in the assays with liver homogenates from rats fed trans fat or cis fat. This suggests that DMBA required a moderate to high level of polyunsaturated corn oil to produce a positive mutagenic response. / Source: Dissertation Abstracts International, Volume: 47-03, Section: B, page: 0871. / Thesis (Ph.D.)--The Florida State University, 1986.

This project was designed to assess the potential for contamination of produce during irrigation with wastewater from animal operations. Dairy wastewater from the University of Arizona Campus Dairy Research Center was used to irrigate three different types of vegetable crops: lettuce, carrot, and bell pepper. This study was conducted over two consecutive years. The crops were planted in February and vegetables were harvested from May through July. Irrigation water and vegetable samples were examined for Escherichia coli, Clostridium perfringens, Listeria monocytogenes, and coliphage. In the dairy wastewater, E. coli concentrations averaged 5.7 x 10⁵ MPN/100 mL in the first year (2000), and 9.9 x 10⁷ MPN/100 mL in the second year (2001). C. perfringens concentrations were nearly the same in both years (1.7 x 10⁴ and 3.4 x 10⁴ CFU per 100 mL). Coliphage averaged 2.0 PFU/mL in 2000 and 1.3 x 10⁴ PFU/mL in 2001 in wastewater. E. coli was detected with greater frequency on carrots (100 and 96%) succeeded by lettuce (67 and 96%) and bell peppers (63 and 58%). The same was true for C. perfringens : carrots (100%), lettuce (86 and 88%), and bell peppers (100 and 50%). Coliphages were not detected on any of the vegetable crops except for average concentrations of 2 PFU/g on lettuce in the first year. L. monocytogenes was not detected on any of the vegetable samples. ANOVA test results indicates that E. coli and C. perfringens concentrations on three crops were statistically different (p < 0.0001) which suggest that the degree of contamination on the surface of the vegetables depends on where the edible portion of the crop is situated (above the soil or under the soil). The greatest contamination occurred on the carrots followed by lettuce and bell peppers. E. coli and C. perfringens were recovered from the carrots, bell peppers, and soil 55 days after wastewater irrigation of the plots had ceased. Positive correlations (p < 0.05) were found between E. coli and C. perfringens density and soil moisture content. The greatest risk of infection from pathogenic E. coli (O157:H7) occurs from consumption of lettuce and carrots. The annual risk of infection from consumption of all three vegetables was above the acceptable risk of 1:10,000 per year. The results of this study suggest that a more strict irrigation water quality standard for root and leafy vegetables might be appropriate to prevent the risk of infection in exposed population.

Pasta was produced from soft wheat supplemented with cowpea. Acid detergent fiber values increased from 0.4% in the soft wheat pasta (SWP) to 1.1% in the 30% cowpea pasta (CP). Cowpea supplementation provided an increase in total and available lysine from 42 to 113% and 39 to 117%, respectively. Chemical scores for preschool children increased from 56 in the SWP to 89 in the 30% CP. For school children the 20% CP provided a score of 102. The in vitro protein digestibility (IVPD) of cowpea was lower than that of soft wheat; as a result cowpea reduced the IVPD of SWP from 84% to a value of 78% for the 30% CP. The protein content of SWP was 10.9% while the CP ranged from 11.3 to 14.2%. Considering IVPD values, SWP contained 9.2% digestible protein and CP from 9.2 to 11.1%. After cooking, only the 30% CP displayed trypsin inhibitor activity. Upon visual examination, cowpea improved the color of SP making it comparable to the durum semolina control (DSC) but lacking its translucency. A sensory panel reported no difference in acceptability among treatments. Cooked weights were similar to the SWP, except with 30% replacement when a decrease was observed. CP, after 10 minutes of cooking demonstrated reduced loss as supplementation was increased. After 20 minutes all treatments had similar cooking loss compared to the SP. All treatments displayed cooking quality results significantly different from the DSC.

<p> This study investigated the use of sweet potatoes (<i>Ipomoea batatas </i>) as a basic component to develop a medium for cultivation of lactic acid bacteria (LAB). Extract from baked sweet potatoes was used to form a sweet potato medium (SPM). SPM was supplemented with 4 g/L of each nitrogen source (beef extract, yeast extract, and proteose peptone #3). Lactobacilli MRS was used as a control medium. Ten LAB strains were used to determine the suitability of SPM serving the growth of LAB. Our results showed no significant (<i>p</i> &lt; 0.05) differences in the optical density, maximum specific growth rates, and bacterial populations between MRS and SPM. SPM also maintained higher pH values throughout the incubation period compared to that in MRS. The cost of SPM was 47% less than the cost of MRS. Further step was taken to determine the suitability of SPM serving LAB enzymatic activity. LAB strains growing in SPM showed relatively higher &beta;-glucosidases, acid phosphatase, and phytase activities and lower &agr;-glucosidase compared to that in MRS. Strains of <i>L. reuteri</i> showed the highest enzymatic activities of &agr;-glucosidase, acid phosphatase, and phytase whereas <i> L. delbrueckii</i> subsp. <i>bulgaricus</i> showed the highest &beta;-glucosidases activity. Thus the enzymatic activity of <i>L. reuteri</i> growing in SPM was enhanced using six different metal ions. The response of <i> L. reuteri</i> strains to metal ions found to be strain dependent. The addition of Mg²⁺ and Mn²⁺ followed by the addition of Ca²⁺ showed the highest enhancement effect on all tested enzymes. These findings indicated that SPM is a suitable medium serving the growth and bioactivities of LAB and thus could be used as an alternative low cost medium.</p>

<p> Consumption of fruits and vegetables has been associated with neuroprotection and cognitive benefits throughout the life span. These associations have sparked interest in plant-derived polyphenols as biologically active agents with potential for targeting brain benefits. However, little is known regarding the ability of the polyphenols or their metabolites from polyphenol-rich products to cross the blood-brain-barrier, and be available for biological action. Furthermore, additional insight is needed on factors affecting the absorption and brain distribution of polyphenol metabolites <i>in vivo.</i> To fill gap in current knowledge, this thesis will focus on the effects of diabetogenic diet and diabetic state which have been considered potential risk factors for neurodegenerative disease on polyphenol bioavailability from a 'Standardized Grape Polyphenol' (grape seed extract, Concord grape juice and resveratrol). Additionally, this thesis will provide novel evidence on plasma pharmacokinetics and regional brain distribution of polyphenol metabolites from apple/grape seed and bilberry extracts in a weaning piglet model. </p><p> We have found that background diabetogenic diet had limited effects on polyphenol plasma levels and brain bioavailability in a healthy Sprague-Dawley rat model. However, the diabetic state negatively influenced polyphenol metabolite levels in plasma and brain tissues, possibly in part, due to excessive excretion in urine. By using a young piglet model, we determined plasma pharmacokinetics of polyphenol metabolites using physiological and pharmacological doses of apple/grape seed and bilberry extracts. We found that in a physiological dose achievable by supplementation, polyphenol metabolites were able to cross blood-brain barrier to deposit in the brain. There was a difference in regional brain deposition with cerebellum being a preferred site for accumulation. Our data warrant the future design of functional tests on aging-related diseases, specifically Alzheimer's disease as well as improvement in cognitive and memory in healthy infant/child model.</p>