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A Eulerian-Lagrangian model was used to predict the trajectory and spatial distribution of odor and odorants downwind from an industrial facility with multiple sources of odor emissions. Specifically, the model was used to simulate the... more
A Eulerian-Lagrangian model was used to predict the trajectory and spatial distribution of odor and odorants downwind from an industrial facility with multiple sources of odor emissions. Specifically, the model was used to simulate the dispersion of odor from a confined animal feeding operation (CAFO) under different meteorological conditions: (1) during daytime when the boundary layer is usually turbulent due to ground-level heating from solar short wave radiation, and (2) during the evening when deep surface cooling through long-wave radiation to space recreates a stable (nocturnal) boundary layer. Aerial photographs were taken of the CAFO, and the geographical area containing the odorant sources was partitioned into 10 m2 grids. Relative odorant concentrations present at each grid point that corresponded to an odor source were measured on site and then entered into a database. The predicted odor dispersion distance was found to be greater at night-time than during daytime and was...
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Worldwide, both the number and proportion of elderly persons is increasing dramatically. By 2025, it is predicted that there will be 1.121 billion persons over 60 years of age. Most of these elderly will have sensory losses including... more
Worldwide, both the number and proportion of elderly persons is increasing dramatically. By 2025, it is predicted that there will be 1.121 billion persons over 60 years of age. Most of these elderly will have sensory losses including impairment of taste and smell perception. Taste ...
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The purpose of this study was to investigate the taste properties of nucleoside analogs, which are among the current medications used to treat human immunodeficiency virus (HIV) infection. Eighteen unmedicated HIV-positive subjects and 41... more
The purpose of this study was to investigate the taste properties of nucleoside analogs, which are among the current medications used to treat human immunodeficiency virus (HIV) infection. Eighteen unmedicated HIV-positive subjects and 41 healthy control subjects participated in threshold and suprathreshold experiments. All of the nucleoside medications tested were perceived as predominantly bitter (along with other qualities such as metallic, medicinal, sour, astringent, and cooling). The nucleoside analog with the lowest detection thresholds was zidovudine; the detection threshold was 1.47 mM for HIV-infected patients and 2.15 mM for control subjects. Detection thresholds for lamivudine were 4.41 mM for HIV-infected patients and 4.36 mM for control subjects. Detection thresholds for stavudine were 6.39 mM for HIV-infected patients and 5.99 mM for control subjects. Detection thresholds for didanosine were 14.29 mM for HIV-infected patients and 24.0 mM for control subjects. The nucleoside analogs also modified the taste perception of KCl and CaCl2. There were no significant differences between HIV-infected subjects and control subjects for detection threshold values for any of the drugs. However, HIV-infected subjects rated lamivudine, zidovudine, and stavudine as significantly more bitter than did the control subjects at concentrations four times higher than their detection thresholds. This result was not due to use of medications by HIV-infected subjects because none of the subjects (neither HIV-infected nor control) were taking medications.
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Taste and smell have a potent role in the control of intake, although the relation is not a simple one. It is clear that the ability to identify sodium chloride properly by taste in order to correct a salt deficiency is innate; however,... more
Taste and smell have a potent role in the control of intake, although the relation is not a simple one. It is clear that the ability to identify sodium chloride properly by taste in order to correct a salt deficiency is innate; however, preferences for specific foods containing other ...
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Sixteen trained tasters provided sweetness and bitterness intensity ratings for 19 compounds including: acesulfame-K, alitame, aspartame, fructose, glucose, glycine, lactitol, maltitol, monoammonium glycyrrhizinate, neohesperidin... more
Sixteen trained tasters provided sweetness and bitterness intensity ratings for 19 compounds including: acesulfame-K, alitame, aspartame, fructose, glucose, glycine, lactitol, maltitol, monoammonium glycyrrhizinate, neohesperidin dihydrochalcone, neosugar (fructo-oligosaccharide), palatinit (isomalt), rebaudioside-A, sodium cyclamate, sodium saccharin, stevioside, sucralose, sucrose, and thaumatin. With increasing concentration, high-potency sweeteners including acesulfame-K, neohesperidin dihydrochalcone, sodium saccharin, rebaudioside-A, and stevioside tended to become more bitter. Low-potency sweeteners including fructose, sucrose, and lactitol tended to become less bitter with increasing concentration.
Research Interests: Cognitive Science, Psychophysics, Perception, Concentration, Brain, and 7 moreHumans, Female, Male, Taste, Gustation, Intensity, and Neurosciences
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By the turn of the century, there will be considerable shifts in demographics, including a massive increase in our aging population. As we plan for better nutrition in the twenty-first century, the special sensory and nutritional needs of... more
By the turn of the century, there will be considerable shifts in demographics, including a massive increase in our aging population. As we plan for better nutrition in the twenty-first century, the special sensory and nutritional needs of the elderly must be taken into account. Chemosensory losses, specifically decrements in the senses of taste and smell, can lead to inadequate intake, especially in the elderly sick. These losses result not only from anatomic changes that occur during normal aging but also from certain diseases, pharmacological and surgical interventions, radiation, and environmental pollutants. The design of foods for the elderly that could both compensate for these chemosensory losses and meet nutritional needs presents new challenges and opportunities for the food industry.
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Repeated exposure to a tastant often leads to a decrease in magnitude of the perceived intensity; this phenomenon is termed adaptation. The purpose of this study was to determine the degree of adaptation of the sweet response for a... more
Repeated exposure to a tastant often leads to a decrease in magnitude of the perceived intensity; this phenomenon is termed adaptation. The purpose of this study was to determine the degree of adaptation of the sweet response for a variety of sweeteners in water and in the presence of two levels of tannic acid. Sweetness intensity ratings were given by a trained panel for 14 sweeteners: three sugars (fructose, glucose, sucrose), two polyhydric alcohols (mannitol, sorbitol), two terpenoid glycosides (rebaudioside-A, stevioside), two dipeptide derivatives (alitame, aspartame), one sulfamate (sodium cyclamate), one protein (thaumatin), two N-sulfonyl amides (acesulfame-K, sodium saccharin), and one dihydrochalcone (neohesperidin dihydrochalcone). Panelists were given four isointense concentrations of each sweetener by itself and in the presence of two concentrations of tannic acid. Each sweetener concentration was tasted and rated four consecutive times with a 30 s interval between each taste and a 2 min interval between each concentration. Within a taste session, a series of concentrations of a given sweetener was presented in ascending order of magnitude. Adaptation was calculated as the decrease in intensity from the first to the fourth sample. The greatest adaptation in water solutions was found for acesulfame-K, Na saccharin, rebaudioside-A, and stevioside. This was followed by the dipeptide sweeteners, alitame and aspartame. The least adaptation occurred with the sugars, polyhydric alcohols, and neohesperidin dihydrochalcone. Adaptation was greater in tannic acid solutions than in water for six sweeteners. Adaptation of sweet taste may result from the desensitization of sweetener receptors analogous to the homologous desensitization found in the beta adrenergic system.
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• The sensory properties of foods influence food choices and provide cues about a food’s nutritional value. • Sensory signals from food elicit salivary, gastric acid, and pancreatic secretions associated with digestion and ultimately... more
• The sensory properties of foods influence food choices and provide cues about a food’s nutritional value. • Sensory signals from food elicit salivary, gastric acid, and pancreatic secretions associated with digestion and ultimately absorption of nutrients. Taste and smell are especially important in activating these digestive secretions because the taste and olfactory systems have closer anatomical connections to the
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The purpose of the workshop entitled Taste and Smell in the Elderly: Behavioral and Nutritional Consequences was 1) to review the current state of knowledge in the area of taste and smell, with emphasis on age-related changes, 2) to... more
The purpose of the workshop entitled Taste and Smell in the Elderly: Behavioral and Nutritional Consequences was 1) to review the current state of knowledge in the area of taste and smell, with emphasis on age-related changes, 2) to identify existing gaps in our knowledge, and 3) to develop future research strategies. There was general agreement that the majority of scientific studies have found impairments in taste and smell acuity in the elderly. These losses may result from normal aging, certain disease states especially Alzheimer's disease, medications, surgical interventions, and environmental exposure. However, there are gaps in our knowledge of the basic mechanisms by which aging and environmental factors may impair the chemical senses in the elderly. Further research is also required in a variety of areas including chemosensory test procedures, food intake, and nutrition to understand fully the impact of chemosensory dysfunction on older individuals.
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ABSTRACT The Carbofil® biological reactor is a type of down-draft reactor that uses impellers to entrain oxygen and increase the opportunity for that oxygen to dissolve in wastewater. The oxygen is used for oxidation of organic matter as... more
ABSTRACT The Carbofil® biological reactor is a type of down-draft reactor that uses impellers to entrain oxygen and increase the opportunity for that oxygen to dissolve in wastewater. The oxygen is used for oxidation of organic matter as well as for nitrification. The system flow scheme through an anoxic reactor provides opportunity for denitrification of nitrate formed in the aerobic reactor. A pilot scale reactor was constructed at a swine finishing farm near Faison, NC and evaluated over an eight week period to establish the potential of the system to efficiently remove ammonia and chemical oxygen demand (COD) from flushed swine wastewater. The odor reduction potential of the system was also evaluated. A total of 16 samples of influent and effluent were taken over the evaluation period and analyzed for chemical constituents. Separate samples were collected on four different occasions near the end of the project and analyzed for odor intensity, irritation intensity, and hedonic tone. Results showed 93% removal of ammonia, 91% removal of soluble Kjeldahl nitrogen, and almost 83% removal of soluble COD.
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Abnormalities in taste and smell functioning occur with elevated frequency in both older adults and patients with cancer. With the predicted increase in both of these populations in the coming decades, it is imperative to evaluate... more
Abnormalities in taste and smell functioning occur with elevated frequency in both older adults and patients with cancer. With the predicted increase in both of these populations in the coming decades, it is imperative to evaluate potential interventions that are designed to help older cancer patients compensate for the additive burden of this disease and its treatment on age-related taste and smell losses. The purpose of the current study was to determine if providing instruction and products for flavor enhancement of foods to elderly cancer patients in addition to nutritional information would improve their nutritional status, and, by extension, functional and immune status as well as quality of life. One hundred and seven subjects enrolled in the study. Fifty-four subjects were in the experimental group that received flavor enhancement plus nutritional information; fifty-three control subjects received only nutritional information. Subjects were evaluated 1 month, 3 months, and 8...
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Historically, unpleasant odors have been considered warning signs or indicators of potential risks to human health but not necessarily direct triggers of health effects. However, citizen complaints to public health agencies suggest that... more
Historically, unpleasant odors have been considered warning signs or indicators of potential risks to human health but not necessarily direct triggers of health effects. However, citizen complaints to public health agencies suggest that odors may not simply serve as a warning of potential risks but that odor sensations themselves may cause health symptoms. Mal-odors emitted from large animal production facilities and wastewater treatment plants, for example, elicit complaints of eye, nose, and throat irritation, headache, nausea, diarrhea, hoarseness, sore throat, cough, chest tightness, nasal congestion, palpitations, shortness of breath, stress, drowsiness, and alterations in mood. There are at least three mechanisms by which ambient odors may produce health symptoms. First, symptoms can be induced by exposure to odorants (compounds with odor properties) at levels that also cause irritation or other toxicological effects. That is, irritation--rather than the odor--is the cause of ...
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Historically, taste research has often been guided by the concept that there are only four (or possibly five) basic taste qualities (sweet, sour, salty, and bitter, and possibly "umami"). All other tastes have been presumed to... more
Historically, taste research has often been guided by the concept that there are only four (or possibly five) basic taste qualities (sweet, sour, salty, and bitter, and possibly "umami"). All other tastes have been presumed to be combinations of these basic tastes. This psychophysical concept has been extended to electrophysiological data. That is, the neural code for each basic taste is hypothesized to be coded by a dedicated channel of neurons (the "Labeled-Line" theory); i.e., one group of neurons signals "salty" and another separate group signals "sweet." Numerous psychophysical and electrophysiological findings, however, cannot be accomodated by this quadripartite theory, which limits taste to four basic qualities and four basic neuron types. Rather, the data described in this article suggest that the range of taste is more extensive than four or five basic tastes, and that this breadth of taste quality results initially from the activati...
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Two experiments were performed to determine the effect of taste and odor stimuli on secretion rate of salivary IgA in young and elderly individuals. In Experiment 1, three stimuli were applied to the tongue: 1) "flavor" drops... more
Two experiments were performed to determine the effect of taste and odor stimuli on secretion rate of salivary IgA in young and elderly individuals. In Experiment 1, three stimuli were applied to the tongue: 1) "flavor" drops (60% sugar, 5% cocoa powder, and 0.1 % Irish cream odor); 2) sugar (60%); and 3) water. In Experiment 2, four different foods (chicken broth, onion soup, corn, and carrots) were tested with and without monosodium glutamate (MSG). The stimuli in both experiments were delivered three times in a one hour period: t=0, t=30 minutes, t=60 minutes. The results of Experiment 1 indicated that application of sugar (taste alone) and flavor (taste and odor combined) to the tongue induced significantly higher secretion rates of sIgA than the application of water in both elderly and young subjects. In addition, flavor application produced significantly higher secretion rates of sIgA than sugar application alone. Secretion rates of sIgA in young persons were signifi...
Research Interests: Aging, Humans, Female, Male, Taste, and 7 moreAged, Saliva, Odors, Adult, Analysis of Variance, Enzyme Linked Immunosorbent Assay, and Salivary Glands
We conducted two experiments to determine the effects of dietary copper concentration and source on odor characteristics of swine waste. In both experiments, 192 weanling gilts and barrows were allotted to 24 pens. Pens were randomly... more
We conducted two experiments to determine the effects of dietary copper concentration and source on odor characteristics of swine waste. In both experiments, 192 weanling gilts and barrows were allotted to 24 pens. Pens were randomly assigned to one of six dietary treatments, consisting of control (10 ppm Cu as cupric sulfate, CuSO4), 66 or 225 ppm Cu as CuSO4, or 33, 66, or 100 ppm Cu as cupric citrate (Cucitrate). An antibiotic was included in the diets for Exp. 1, but not Exp. 2. On d 28, fecal samples were randomly obtained from one pig per pen and stored at -20 degrees C until preparation and evaluation by an odor panel. The odor panel consisted of 10 individuals, and each panelist evaluated the odor intensity, irritation intensity, and odor quality of the samples. In Exp. 1, the odor and irritation intensity of the feces were lower (P < .05) from animals consuming diets containing 225 ppm Cu as CuSO4 and 66 or 100 ppm Cu as Cu-citrate compared to the control. The odor quali...
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Taste and smell losses in the elderly can reduce appetite and lead to inadequate dietary intake. Although these chemosensory deficits are generally not reversible, sensory interventions including intensification of taste and odor can... more
Taste and smell losses in the elderly can reduce appetite and lead to inadequate dietary intake. Although these chemosensory deficits are generally not reversible, sensory interventions including intensification of taste and odor can compensate for perceptual losses. One method for "treatment" of chemosensory losses involves sensory enhancement of foods with flavors and monosodium glutamate (MSG). Amplification of flavor and taste can improve food palatability and acceptance, increase salivary flow and immunity, and reduce oral complaints in both sick and healthy elderly.