Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 91-97). Also available via the Internet.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 60-63). Also available via the Internet.

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Because of the increased demand for low calorie products, more products are being sweetened with artificial sweeteners. Perceived sweetness may be affected by other food ingredients, such as hydrocolloids. The purpose of this study was to examine the effects of xanthan gum, carboxymethyicellulose-low, and carboxymethylcellulose-medium on the attributes of a lemon flavored beverage sweetened with an artificial sweetener. Each hydrocolloid was added to the beverages to attain the following viscosities - 10 cps, 15 cps, and 20 Ctps. The table top formulations of artificial sweeteners used to sweeten the beverage samples were Sweet One® (contains acesulfame-K) and Equal® (contains aspartame). A modified Quantitative Descriptive Analysis method was used as the sensory evaluation technique to determine the intensity of sourness, sweetness, lemon flavor, bitterness, and aftertaste in the beverages of varying viscosities. In the samples containing Sweet One®, CMC-L increased sweetness whereas in the samples containing Equal®, sweetness first decreased significantly before increasing with increasing viscosity. CMC-M did not Significantly affect the sweetness of either sweetener although it tended to decrease the sweetness of Equal®. CMC-L and CMC-M decreased lemon flavor and sourness in the samples with both sweeteners; CMC-L decreased the intensity of these attributes more than CMC-M. The only significant change caused by the addition of xanthan gum to the beverages was a decrease in the sweetness of the samples sweetened with Equal®. Xanthan gum affected the attributes of the lemon flavored beverages the least whereas CMC-L had the greatest effect on the attributes. / Master of Science

The relationships among artificial sweetener consumption, body weight, and energy intake were examined using a rat model and a survey of college students. The rats were divided into four treatment groups and one control group (n=10 per group). Group 1 was provided with a 10% sucrose solution; group 2, a 50% sucrose solution; group 3, a 0.05% aspartame solution; and group 4, a 0.25% aspartame solution. All groups were provided with rat chow and water ad libitum. Analysis of variance (ANOVA) and Duncan's multiple range test were used to evaluate the data from the rat study. No differences existed among the groups for weight gain or total energy intake. Differences did exist among the groups for solution and food intake with the two groups given sucrose consuming the greatest amount of sweetened solution and the least amount of food. In the survey of college students, the human subjects' gender, perception of their weight, weight status, dieting status, weight consciousness, weight change over a one year period, and total caloric intake/ total energy expenditure were examined in relation to their consumption of diet soda and packets of table top artificial sweeteners. / Master of Science

N-Flate™ and a sweetening system of 1.5% aspartame, 35.5% fructose, and 63% polydextrose (AFP) were evaluated for their potential as fat and sugar substitutes, respectively. Four cupcake variations were prepared to compare the effects of replacing shortening with N-Flate™, and sugar with AFP. The four variations were shortening/sugar, shortening/AFP, N-Flate™/sugar, and N-Flate™/AFP. The evaluation involved objective measurements of the batter and the baked cupcakes, and sensory evaluation of the cupcakes. Results of the objective measurements showed that the batter from the two variations prepared with N-Flate™ had a Significantly higher pH and specific gravity than the two variations prepared with shortening. A lower cake volume, a firmer texture, a higher moisture content, and a darker crumb color were also observed in the two variations prepared with N-Flate™. The batter from the two variations prepared with AFP also had a higher pH and specific gravity than the two variations prepared with sugar. A lower cake volume, a firmer texture, a higher moisture content, and a lighter crust color were also observed in the two variations prepared with AFP. Among the objective measurements, interaction effects were significant for specific gravity, volume, crust color and tenderness. Sensory evaluation results showed that the two variations prepared with N-Flate™ were less tender and have poorer cell uniformity than those prepared with shortening. Variations prepared with AFP were found to be less moist, have a more bitter crust and crumb, and better cell uniformity than those prepared with sugar. No interaction effects were observed for any of the sensory attributes. / Master of Science

Submitted in fulfillment of the requirements of the degree of Doctor of Philosophy in Chemistry, Durban University of Technology, 2015. / Materials which show sweetness are classified as nutritive sweeteners and non-nutritive sweeteners or artificial sweeteners. In the present work, capillary electrophoresis and electrochemical biosensors have been used to analyse and quantify the natural and chemical artificial sweeteners in different food samples. The experimental work was further supported by computational studies. Capillary electrophoresis (CE) is a technique in which charged molecules can efficiently be separated in a buffer solution within a capillary tube under the influence of a strong electric field. While in the case of a biosensor, the analyte interacts with the bioreceptor and the resulting output is measured by a specially designed transducer. Steviol glycosides (rebaudioside A and stevioside) are natural sweeteners, extracted from Stevia rebaudiana Bertoni belonging to the Asteraceae family. On the other hand, neotame and sucralose are chemical sweeteners manufactured from their structural analogues aspartame and sucrose, respectively. Accordingly in this work, two CE modes, namely electro kinetic chromatography–capillary electrophoresis (EKC–CE) and an indirect UV-Capillary zone electrophoresis were used for the evaluation of analytes studied. Steviol glycosides (rebaudioside A and stevioside) and neotame diastereomers (L,L and D,D) were analysed using EKC-CE in the presence of a chiral separating agent β-cyclodextrin (TM-β-CD). However, since sucralose demonstrates chromophore-like properties, an indirect UV-CZE method was therefore developed using simple amines (morpholine, piperidine, ethylamine and triethylamine) as the background electrolytes (BGE). The optimum separation conditions in EKC-CE were; UV detection at 210 nm, 50 mM phosphate buffer, 30 mM TM-β-CD, 20 kV applied voltage, 5 s hydrodynamic injection and pH of 8.0 and 5.5 (for steviol glycosides and neotame), respectively. On the other hand, optimum separation conditions for the indirect UV-CZE method were; UV detection at 230 nm, 0.2 M morpholine buffer at pH 12.0, +20 kV applied voltage, 30 0C cassette temperature and 6 s sample injection. Furthermore, a highly sensitive and novel electrochemical biosensor was developed using platinum and glassy carbon electrodes fabricated with different nanomaterials. Accordingly, cytochrome c/graphene oxide – gold NPs/multiwalled carbon nanotubes (MWCNTs) modified platinum electrodes were used for the analysis of rebaudioside A. Similarly, copper NPs capped with ammonium piperidine dithiocarbamate-MWCNTs-β-cyclodextrin and laccase/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) immobilized graphene oxide-p-aminothiophenol capped ZnO NPs nanocomposites modified with glassy carbon electrodes were developed for the determination of neotame and sucralose, respectively. The electrochemical behaviour of these sweeteners towards the developed sensors was tested by using cyclic voltammetry and differential pulse voltammetry under optimum experimental conditions (pH, scan rate, accumulation time, accumulation potential, pulse amplitude, voltage step and voltage step time). The prepared nanocomposites were characterized using thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. It was found that the developed electrochemical biosensors showed excellent catalytic activity towards the determination of natural and chemical sweeteners in commercially available food samples. Additionally, a comparative study between capillary electrophoresis and biosensor methods revealed that at optimum experimental conditions, typical detection limits ranging from 0.02017 to 0.07386 mM for steviol glycosides, 0.01857 to 0.08214 mM for neotame diastereomers and for sucralose 0.2804 mM were achieved. In contrast to CE methods, biosensor methods attained very low detection limits of 0.264 µM, 0.013 mM and 0.325 µM for rebaudioside A, neotame and sucralose, respectively. The unique properties of the nanomaterials in combination with electro chemical techniques provided best results with shorter analysis time in contrast to the conventional separation methods. Finally, the computational molecular modelling tools were used to better understand the results obtained from the separation mechanisms using capillary electrophoresis. The interaction of β-cyclodextrin with steviol glycosides/neotame diastereomers and sucralose with the amine buffers were studied and the computational results were in good agreement with the elution orders observed in capillary electrophoresis. Furthermore, docking studies were performed to predict the binding affinity interactions between the artificial sweeteners and biomolecules (cytochrome c and laccase) to understand a molecular level.

Orientador: Patricia Fernanda Felipe Pinheiro / Resumo: Introdução: A hipótese da “programação fetal” defende que eventos ocorridos durante a vida intrauterina exerçam influência na patogênese de doenças na vida adulta. Fatores ambientais podem programar no indivíduo o surgimento precoce de doenças cardiovasculares e metabólicas. Atualmente, há um aumento no consumo de adoçantes artificiais associados a tratamentos para a perda de peso e no controle do diabetes, sendo a sacarina sódica um dos mais consumidos. Entretanto, durante a gestação e lactação, o uso de sacarina sódica é restrito, por ser permeável a placenta, interagindo com o concepto e, por compor o leite materno. Embora os efeitos do uso de adoçantes sobre o peso corpóreo e o metabolismo sejam bastante conhecidos, não há relatos de pesquisas que relacionam a programação fetal pelo uso de sacarina sódica com o desenvolvimento pós-natal do testículo. Desta forma, o presente estudo visa investigar a influência do uso da sacarina sódica e da glicose na saúde materna e reprodutiva dos descendentes machos. Material e métodos: Ratas Sprague Dawley foram alimentadas durante a prenhez e lactação com dieta padrão para roedores, água filtrada ad libitum e suplementadas com iogurte natural desnatado (Grupo Controle Iogurte, n= 9); iogurte natural desnatado adoçado com solução de glicose (Dinâmica®) a 5% (v/v) (Grupo Glicose, n= 10); iogurte natural desnatado adoçado com solução de sacarina sódica (Dinâmica®) a 0,3% (v/v) (Grupo Sacarina Sódica, n= 10). As dietas líquidas foram prep... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: The "fetal programming" hypothesis argues that events that occur during intrauterine life have an influence on the pathogenesis of diseases in adulthood. Environmental factors can program in the individual the early onset of cardiovascular and metabolic diseases. Currently, there is an increase in the consumption of artificial sweeteners associated with treatments for weight loss and diabetes control, with sodium saccharin being one of the most consumed. However, during pregnancy and lactation, the use of sodium saccharin is restricted, since it is permeable to the placenta, interacting with the conceptus, and for composing breast milk. Although the effects of the use of sweeteners on the body weight and metabolism are well known, there are no reports of researches which relate fetal programming through the use of sodium saccharin to the postnatal development of the testis. Thus, the present study aims to investigate the influence of the use of sodium saccharin and glucose on the maternal and reproductive health of male offspring. Material and methods: Dams Sprague-Dawley rats were fed during pregnancy and lactation with a standard chow for rodents, filtered water ad libitum and supplemented with low-fat plain yogurt (Yogurt Control Group, n = 9); low-fat plain yogurt sweetened with 5% (v/v) glucose solution (Dinâmica®) (Glucose Group, n = 10); low-fat plain yogurt sweetened with 0.3% (v/v) sodium saccharin solution (Dinâmica®) (Sodium Saccharin Group, n = 10). ... (Complete abstract click electronic access below) / Mestre

In recent years, new classes of aquatic pollutants have received growing concerns from the environmentalists due to their unclear effects and increasing release into the water environment. Generally, before entering the aquatic ecosystem, many of these emerging contaminants are deemed safe active ingredients in the commercial products. This may lead to the underestimation of their potential impacts to the environment, once these substances were drained into the natural waters. So far, a wide range of emerging contaminants are still not well studied. In this thesis work, the environmental behaviors for two typical groups of emerging contaminants, which are frequently used in personal care products, are systematically probed in the aquatic ecosystem. One is the hydrophilic compounds - artificial sweeteners and the other one is the moderate hydrophobic compounds - ultraviolet (UV) filters. Acesulfame and sucralose are two of the most commonly used artificial sweeteners, which are a newly recognized class of emerging contaminants due to their widespread occurrence and extreme persistence in water environment. To date, however, their environmental behaviors, fates as well as long term ecotoxicological contributions in our water resources still remain largely unknown. In this work, a photodegradation investigation with UV/TiO2 was performed on these two artificial sweeteners, which projected their potential impacts under prolonged exposure to intensive solar irradiation. Real-time observation of the degradation profiles in both sweeteners illustrated that formation of new photo by-products under prolonged UV irradiation is highly viable. For the first time, acute toxicity for the degradates of these two sweeteners were measured and the enhancement in their ecotoxicity has been observed during the irradiation. In an attempt to neutralize this prolonged environmental threat, the feasibility of UV/TiO2 as an effective mineralization process in wastewater treatment was evaluated for both sweeteners. As a result, relatively higher removal efficiencies for acesulfame and sucralose were achieved in this study. For UV filters, a comprehensive investigation on their environmental behaviors and impacts was described in this thesis, covering the occurrence study in surface water and biota, environmental fate and their ecological risks. In the first step, an analytical method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of twelve UV filters in the environmental waters, which achieved good sensitivity to sub-ng/L levels. To monitoring their occurrence in local marine environment, the regional distribution of these sunscreen compounds was monitored along the coastline of Hong Kong. At the same time, considering the intensive consumption of sunscreen products in hot weathers, seasonal variation of UV filters between summer and winter was taken into consideration in our occurrence study. Additionally, we also monitored their occurrence in the drinking water supply system of Hong Kong, including the source water in Dongjiang, raw water in local reservoirs and tap water collected from urban communities, to support a good management on the reliable water supply. Furthermore, the distribution results indicated that the incomplete removal of UV filters in the effluents could be a major source for their release into the environmental waters. Aiming to achieve the complete removal of such compounds, a powerful technique of ozonation was employed in this study and the preliminary operational conditions were further provided. Secondly, in order to gain a better understanding of their environmental fate in surface water, a simulative catalytic photodegradation study with UV/TiO2 were performed to investigate the photostability, phototoxicity and the transformation pathways of seven selected UV filters. During the photodegradation, several transformation products were primarily identified. Thirdly, since lipophilic sunscreens were easily accumulated in the biota, we also made efforts to monitor their occurrence in marine organisms of different species, including farmed fish, wild mussels, prawns and sea urchin, which were collected from local offshore areas. Last but not the least, according to the measured concentrations of UV filters in Hong Kong marine environment, we further performed the ecological risk assessment with the approach specific to the marine aquatic compartment, so as to provide the overall understanding on the environmental impacts of these UV filters.

Obesity is a serious health concern in modern society. One way to reduce caloric intake is with nonnutritive sweeteners (NNS). However, recent research suggests they may be compounding the obesity problem. Nonnutritive sweeteners have been linked to increased body mass in a few studies and may be a barrier to effective weight management for some individuals. Under the framework of the health belief model, the research question was: Does this pattern of NNS-BMI covariance exist in young adults at the University of North Florida and, if so, are there other dietary or activity differences that might partially explain this relationship? A sample of 113 students completed an online survey based on the Youth Risk Behavior Surveillance Survey to answer this question. Their responses quantified BMI, activity level estimates, NNS intake, and produce consumption. There was a no trend of covariance between BMI and NNS intake overall. However, there was a significant relationship between length of NNS usage and both BMI (p<0.01) and NNS intake (p<0.05). A positive correlation also existed between NNS usage and fruit and vegetable intake (p<.005). Weight variability was positively related to NNS due to the maintenance of previous weight loss (p<0.005). There was no correlation between NNS and activity. There is a tendency to have a higher BMI the longer NNS is consumed. This pattern does not appear to be explained by nutrient intake or activity. However, it may be due to increased tolerance towards sweets over time. Nurse practitioners can make recommendations that facilitate healthy behaviors amongst their patients. Therefore, this is an important issue for advanced practice nursing.