Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Taste modeling”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,333 records · Page 74Linked to original sources

Comparison of the amounts of volatile compounds in French protected designation of origin virgin olive oils.

Headspace solid-phase microextraction (HS-SPME) -gas chromatography using flame ionization detection and multivariate analysis were applied to the study of the specificity of protected designation of origin (PDO) virgin olive oils produced in a southern French region (Alpes-Maritimes) based on their volatile compounds. A total of 35 PDO olive oils from Nice, 6 commercial oils, and 12 other French PDO olive oils were analyzed. Recorded data were subjected to principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). The method developed here was able to perfectly distinguish different qualities of olive oils. Representative samples from each class obtained by chemometric treatment were analyzed by HS-SPME and GC-MS. PCA and SIMCA of chromatographic data were related to sensory analysis and led to a better understanding of the chemical features and observed sensory effects of olive oils.

Chromatography, Gas↗

Alcohol and the appetizer effect.

In order to evaluate the effects of alcohol on appetite, 12 unrestrained and 10 restrained men ate lunch 20 min after consuming preloads consisting of water, an alcoholic fruit juice (alcohol) and a non-alcoholic fruit juice (juice). The unrestrained men ate significantly less after the juice preload, and ate most after alcohol. Intake was not altered significantly in the restrained men. However, both the alcohol and juice preloads reduced rated hunger and increased fullness, relative to the water control, in both restrained and unrestrained men. When the relationship between rated appetite and intake within the test meal was modelled mathematically, it was found that hunger increased more during the initial stages of the test meal in the unrestrained men who had consumed alcohol than in any other condition. No such effects were seen in the restrained subjects. Overall, these results suggest that alcohol has a complex action on appetite, which includes some form of appetite stimulation, and this may explain the excess energy intake reported previously in moderate alcohol consumers.

Adult↗

Freundlich adsorption isotherms of agricultural by-product-based powdered activated carbons in a geosmin-water system.

The present study was designed to model the adsorption of geosmin from water under laboratory conditions using the Freundlich isotherm model. This model was used to compare the efficiency of sugarcane bagasse and pecan shell-based powdered activated carbon to the efficiency of a coal-based commercial activated carbon (Calgon Filtrasorb 400). When data were generated from Freundlich isotherms, Calgon Filtrasorb 400 had greater geosmin adsorption at all geosmin concentrations studied than the laboratory produced steam-activated pecan shell carbon, steam-activated bagasse carbon, and the CO2-activated pecan shell carbon. At geosmin concentrations < 0.07 microg/l for the phosphoric acid-activated pecan shell carbon and below 0.08 microg/l for a commercially produced steam-activated pecan shell carbon obtained from Scientific Carbons, these two carbons had a higher calculated geosmin adsorption than Filtrasorb 400. While the commercial carbon was more efficient than some laboratory prepared carbons at most geosmin concentrations, the results indicate that when the amount of geosmin was below the threshold level of human taste (about 0.10 microg/l), the phosphoric acid-activated pecan shell carbon and the Scientific Carbons sample were more efficient than Filtrasorb 400 at geosmin removal.

Adsorption↗

[Olfactory and gustatory sweating--case report on reflex facial hyperhidrosis].

Localised hyperhidrosis is comparatively rare among the vegetative disorders. A case of pathological gustatory and olfactory sudation is reported, with the sequence of symptoms corresponding to that of the Frey syndrome. Working from the reflex nature of the phenomen, the paper puts forward a model to account for the delayed onset of the manifestation following a peripheral lesion. It is assumed that readjustment of the reflex excitation level takes place according to a modification in peripheral afference, and that a decompensation of the central control mechanisms results in a pathological enhancement of the reflex. The hypothesis of peripheral efferentisl denervation hypersensitivity appears insufficient to account for the delay in manifestation, or even to account for the classic Frey syndrome following an affection of the parotid gland.

Humans↗

Sensitivity of the olfactory sense declines with the aging in senescence-accelerated mouse (SAM-P1).

The decline in olfaction with age is well documented in histological, psychological, and electroencephalographical studies. However, there are few electrophysiological studies on changes in the sensitivity of the peripheral olfactory cells with age. We evaluated the behavior, the amplitude of electro-olfactogram (EOG), and the thickness of the olfactory epithelium in the Senescence-Accelerated Mouse (SAM-P1). This strain of mouse exhibits accelerated senescence and age-related pathologies, and it is commonly used as a model for research on aging. Its median survival time is 55 weeks. To ensure our results would be restricted to the olfactory system, we chose vanillin as a stimulus, because this stimulus has no definitive chorda tympani (VII) response, and we verified that it is tasteless. The data demonstrate that olfactory sensitivity to vanillin decreases dramatically with age in these mice, and that this is due to loss in the number of olfactory receptor cells.

Aging↗

Olfactory loss as a result of toxic exposure.

Olfactory loss can occur through accidental exposure, poor industrial hygiene, or exposure to low levels of toxins in the ambient air over long periods. This loss can lead to transient olfactory disorders, irreversible anosmia, temporary olfactory fatigue, or industrial anosmia. Inevitably, a practicing otolaryngologist will encounter a patient with complaints of decreased smell and taste that initially may be difficult to diagnose and treat. Much of the challenge in evaluating a patient with disturbances of olfaction is in obtaining adequate quantitative measurements of sensory dysfunction and identifying a source for the olfactory loss. Although there is no particular test for environmental toxins as a source of olfactory loss, an accurate cause can be determined by obtaining a careful, detailed history. A significant exposure history and lack of more common causes of olfactory loss strengthens an argument for environmental toxins as an etiology. Unfortunately, no available treatments can reverse permanent damage caused by toxic exposure, but removal from the source of toxins may allow for repair of the olfactory system and return of normal function, especially in acute exposures. Despite the increasing number of studies investigating toxic exposure on olfactory function, these effects are understood poorly. With continued study of human exposure to these substances and the use of animal models, the mechanisms by which damage occurs will be understood better and new approaches for diagnosis and treatment will be developed. Furthermore, with increasing regulations of occupational environments and stricter policies on industrial air pollution, olfactory dysfunction secondary to toxicity should become less prevalent.

Drug-Related Side Effects and Adverse Reactions↗

Small molecule insulin mimetics reduce food intake and body weight and prevent development of obesity.

Obesity and insulin resistance are major risk factors for a number of metabolic disorders, such as type 2 diabetes mellitus. Insulin has been suggested to function as one of the adiposity signals to the brain for modulation of energy balance. Administration of insulin into the brain reduces food intake and body weight, and mice with a genetic deletion of neuronal insulin receptors are hyperphagic and obese. However, insulin is also an anabolic factor; when administered systemically, pharmacological levels of insulin are associated with body weight gain in patients. In this study, we investigated the efficacy and feasibility of small molecule insulin mimetic compounds to regulate key parameters of energy homeostasis. Central intracerebroventricular (i.c.v.) administration of an insulin mimetic resulted in a dose-dependent reduction of food intake and body weight in rats, and altered the expression of hypothalamic genes known to regulate food intake and body weight. Oral administration of a mimetic in a mouse model of high-fat diet-induced obesity reduced body weight gain, adiposity and insulin resistance. Thus, insulin mimetics have a unique advantage over insulin in the control of body weight and hold potential as a novel anti-obesity treatment.

Animals↗

Application of Fourier transform Raman spectroscopy for prediction of bitterness of peptides.

The potential application of Fourier transform (FT) Raman spectroscopy to predict the bitterness of peptides was investigated. FT-Raman spectra were measured for the amino acid Phe and 9 synthetic di-, tri-, and tetra peptides composed of Phe, Gly, and Pro. Partial least squares regression (PLS)-1 analysis was applied to correlate the FT-Raman spectra with bitterness intensity values (R(caf) and log 1/T) reported in the literature. Using full cross-validation, Model 1 based on the single spectral data set for the nine peptides yielded a high correlation coefficient for calibration (R = 0.99), but a low correlation coefficient for prediction (R = 0.56). Two models were constructed using the data sets including replicate spectra for the calibrations and were validated using full cross-validation. Using leave-one-sample-set-out calibrations, Model 2, which was developed with the data for the peptides as well as Phe, yielded a low correlation coefficient (R = 0.533) for the prediction of the bitterness, while Model 3 developed with only the peptide data provided better correlation coefficients (R = 0.807 and 0.724 for R(caf) and log 1/T values, respectively). The correlation coefficients for prediction were 0.975 (R(caf) values) and 0.874 (log 1/T values) for Model 4, which was developed using subtracted spectral data (spectra of peptides with higher R(caf) values minus spectra of peptides with lower R(caf) values). Examination of the PLS regression coefficients at wavenumbers most highly correlated with bitterness revealed the importance of hydrophobicity and peptide length on bitterness. This study indicates the potential of FT-Raman spectroscopy as a useful tool for predicting bitterness of peptides and amino acids.

Amino Acids↗

Quantitative structure-activity relationship modeling of alcohol, ester, aldehyde, and ketone flavor thresholds in beer from molecular features.

Three quantitative structure-activity relationship approaches-principal components regression, partial least-squares regression, and alternating conditional expectations-were used to investigate relationships between the flavor thresholds of 38 alcohols, 40 esters, 45 aldehydes, and 43 ketones in beer and their structures. Strong nonlinear relationships between the logarithm of the flavor threshold and four or five structure descriptors were found for each class of compounds (R2 = 0.920, 0.937, 0.920, and 0.928 for alcohols, esters, aldehydes, and ketones, respectively). Simple nonlinear relationships between the alcohol, ester, and aldehyde thresholds and the numbers of hydrogen atoms in the molecules were also demonstrated.

Alcohols↗

Characterization of epoxydecenal isomers as potent odorants in black tea (Dimbula) infusion.

In a black tea (Dimbula) infusion, the potent "sweet and/or juicy" odorants were identified as the cis- and trans-4,5-epoxy-(E)-2-decenals by comparison of their gas chromatography retention indices, mass spectra, and odor quality to those of the actual synthetic compounds. Of the two odorants, cis-4,5-epoxy-(E)-2-decenal has been identified for the first time in the black tea. On the basis of the aroma extract dilution analysis on the flavor distillate obtained using the solvent-assisted flavor evaporation technique from the black tea infusion, these isomers showed higher flavor dilution (FD) factors. The FD factors and concentrations of these odorants in the black tea infusion were observed to be much higher than those from Japanese green tea. In addition, the model studies showed that these odorants were generated from linoleic acid and its hydroperoxides by heating, but the generated amounts of these odorants from linoleic acid were much less than those of its hydroperoxides. It can be assumed from these results that the withering and fermentation, which are characteristic processes during the manufacturing of the black tea, which includes the enzymatic reaction such as lipoxygenase, is one of the most important factors for the formation of the epoxydecenal isomers.

Aldehydes↗

Aging and eating in the rural, southern United States: beliefs about salt and its effect on health.

This paper draws upon qualitative research conducted among older adults in the rural, southern United States in which they articulated their beliefs and experiences with nutrition and foods, and lay models of the connection of diet with chronic disease. Salt emerged as a focus of contention. The goals of the paper are to (1) present the culturally constructed meaning of salt, (2) contrast the cultural meaning with biomedical views, and (3) discuss how these findings can be applied to health education and better doctor-patient communication. Data were collected in two rural communities characterized by high rates of poverty and a high proportion of minority residents. A total of 116 African American, Native American and white adults aged 60 years and older participated in 55 in-depth interviews or seven focus groups. A systematic analysis of text showed that salt was a highly contested component of food. While valued for its role in traditional foods and cuisine, it also held negative connotations because of biomedical links to chronic diseases prevalent in the population. We suggest that attempts to control salt intake are made difficult by the changes in taste perceptions that accompany aging. Respondents' articulation of salt's role in health and disease shows cross-over among different chronic diseases and a lay interpretation of blood as the medium through which salt affects disease. These older adults' narratives demonstrate their attempts to reconcile the important role of traditional foods in their identity as Southerners with their attempts to meet medical recommendations for healthy eating.

Black or African American↗

Growth, development, and aging of orofacial tissues: neural aspects.

Neural factors influence post-natal growth, development, and aging throughout the body. This influence may be mediated through sensory or motor effects interacting with endocrine and immunological factors. Growth effects may be expressed directly by sensory or motor nerves on the tissue or indirectly by motor function. Direct neutrotrophic effects have been well-documented in the development of striated muscle, the taste bud, and the amphibian limb. Evidence for a trigeminal neurotrophic effect on tooth development and facial development is lacking. Growth disturbances of the jaws consequent to lesioning of the trigeminal nerve are due most likely to functional disturbances rather than neutrotrophism. Examples of function impact on orofacial growth are abundant. Oral and facial target tissues, like those elsewhere in the body, determine the nature of the target tissue innervation and its central organization. Central effects consequent to tooth loss or dental pulp entirpation are well-documented. Inflammation and pain may exert growth effects through release of "wound hormones" or secondarily to somatic and autonomic effects. There is evidence that vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) elaborated from sympathetic and parasympathetic neurons may have a modulatory role in growth. While the effects of longstanding motor pathologies on skeletal growth are well-known, concomitant sensory deficits and soft tissue disturbances have not been examined. However, the pathological models beg the question of normal regulation. While muscle develops in the absence of innervation, neurotrophic effects are clearly identified. Little is known about the interaction of simple and complex motor behavior on growth. Regulation of growth is frequently visualized within a form-function paradigm. For example, anterior open bites have been seen as the consequence of tongue thrusting or tongue thrusting as a consequence of open bites. Low tonic forces in posture are thought to be more important in the development of both the face and the dental alveolar complex than the higher intermittent forces in mastication and swallowing. The need for an active (reflex) contribution to growth at the TMJ is in dispute.(ABSTRACT TRUNCATED AT 400 WORDS)

Face↗

Use of starch/xanthan gum combinations as thickeners of cocoa syrups.

The influence of starch-xanthan thickening systems on the sensory, textural and rheological properties of cocoa syrups was studied. The results of whole and partial sensory analyses of syrups obtained under laboratory conditions were presented and compared to those of commercially available syrups. In the evaluation of texture such parameters as hardness, adhesiveness, cohesiveness, gumminess and stringiness were considered. The results of rheological measurements were presented in the form of flow curves as well as viscosity/time and viscosity/ temperature relationships. Flow curves were fitted to the models of Ostwald-de Waele and Casson, which allowed characterising the syrups under study to non-Newtonian, pseudoplastic, and thixotropic fluids. It was concluded that the quantity of thickeners used influenced not only theological, but also textural and sensory properties of the syrups. The decrease of pseudoplasticity and hardness with an increase of xanthan addition was a result of high sugars level in the syrups. This phenomenon was a result of competition between sugars (mono-, di-, and oligosaccharides) and hydrocolloids for water molecules in the systems under study.

Cacao↗

Effectiveness of the SmartMV prototype BeefCam System to sort beef carcasses into expected palatability groups.

This study was conducted to determine the effectiveness of the SmartMV prototype BeefCam Video Imaging System (prototype BeefCam) for classifying beef carcasses into palatability ("certified" or "not certified" as palatable) groups. Carcasses (n = 769) were selected from four beef-packing plants to represent three USDA quality grade groups (Top Choice, TC; Low Choice, LC; and Select, SE). Following chilling, a prototype BeefCam image of the longissimus muscle was obtained for each carcass. Strip loins were collected from the left side of each carcass and aged for 10 d; Warner-Bratzler shear force (WBSF; n = 769) values and consumer panel ratings (hedonic, end-anchored, 9-point ratings for overall like/dislike; n = 500 carcasses) were obtained for cooked steaks. Using information from the images, two regression models were developed to predict the first principal component of WBSF and consumer panel ratings for sorting carcasses based on expected eating quality. Model I used only prototype BeefCam output, whereas Model II used prototype BeefCam output and a coded value for quality grade group. For both models, carcasses with a predicted value of less than 0.0 were certified as producing palatable beef Additional carcasses (n = 292) were evaluated at a fifth and separate packing plant by prototype BeefCam to validate Models I and II. A strip loin was collected from each carcass and WBSF was measured after 14 d of aging. The percentages of validation carcasses that generated tough (WBSF > or = 4.5 kg) steaks were 6.5,5.8,10.7, and 7.9% for, TC, LC, SE, and all carcasses, respectively. Use of Model I certified 51.9, 47.6, 43.8, and 47.3% of TC, LC, SE, and all carcasses, respectively. Of the carcasses certified by use of Model I, 0.0,0.0, 4.1, and 1.4% of TC, LC, SE, and all carcasses, respectively, generated tough steaks. Use of Model II certified 59.7, 47.6, 25.0, and 42.1% of TC, LC, SE, and all carcasses, respectively. Of the carcasses certified by use of Model II, 2.2, 0.0, 3.6, and 1.6% of TC, LC, SE, and all carcasses, respectively, generated tough steaks. For both models, the frequency of carcasses that produced tough steaks in the certified group was lower (P < 0.05) for all validation carcasses sampled compared with that of the original carcass population. Based on the decrease in the frequency of carcasses that produced tough steaks, further development of a commercial BeefCam system is warranted.

Adolescent↗

Flavor release and perception in hard candy: influence of flavor compound-flavor solvent interactions.

The release kinetics of l-menthol dissolved in propylene glycol (PG), Miglyol, or 1,8-cineole (two common odorless flavor solvents differing in polarity and a hydrophobic flavor compound) were monitored from a model aqueous system via atmospheric pressure chemical ionization mass spectrometry (APCI-MS). Breath analysis was also conducted via APCI-MS to monitor release of l-menthol from hard candy that used PG and Miglyol for l-menthol incorporation. The quantities of l-menthol released when dissolved in PG or Miglyol from the model aqueous system were found to be similar and overall significantly greater in comparison to when dissolved in 1,8-cineole. Analogous results were reported by the breath analysis of hard candy. The release kinetics of l-menthol from PG or Miglyol versus from 1,8-cineole were notably more rapid and higher in quantity. Results from the sensory time-intensity study also indicated that there was no perceived difference in the overall cooling intensity between the two flavor solvent delivery systems (PG and Miglyol).

Adult↗

Vesicular glutamate transporter VGLUT2 expression levels control quantal size and neuropathic pain.

Uptake of L-glutamate into synaptic vesicles is mediated by vesicular glutamate transporters (VGLUTs). Three transporters (VGLUT1-VGLUT3) are expressed in the mammalian CNS, with partial overlapping expression patterns, and VGLUT2 is the most abundantly expressed paralog in the thalamus, midbrain, and brainstem. Previous studies have shown that VGLUT1 is necessary for glutamatergic transmission in the hippocampus, but the role of VGLUT2 in excitatory transmission is unexplored in glutamatergic neurons and in vivo. We examined the electrophysiological and behavioral consequences of loss of either one or both alleles of VGLUT2. We show that targeted deletion of VGLUT2 in mice causes perinatal lethality and a 95% reduction in evoked glutamatergic responses in thalamic neurons, although hippocampal synapses function normally. Behavioral analysis of heterozygous VGLUT2 mice showed unchanged motor function, learning and memory, acute nociception, and inflammatory pain, but acquisition of neuropathic pain, maintenance of conditioned taste aversion, and defensive marble burying were all impaired. Reduction or loss of VGLUT2 in heterozygous and homozygous VGLUT2 knock-outs led to a graded reduction in the amplitude of the postsynaptic response to single-vesicle fusion in thalamic neurons, indicating that the vesicular VGLUT content is critically important for quantal size and demonstrating that VGLUT2-mediated reduction of excitatory drive affects specific forms of sensory processing.

Animals↗

Evaluation of guar biscuits for use in the management of diabetes: tests of physiological effects and palatability in non-diabetic volunteers.

A guar-shortbread biscuit has been successfully developed and tested for possible use in the dietary management of diabetes. A dose-response study was undertaken to estimate the amount of guar gum needed in the biscuit recipe to reduce postprandial glycaemia and insulinaemia. A control biscuit and three types of guar biscuit corresponding to a low, medium and high dose of guar (2.9, 6.0 and 9.1 g of guar respectively) were given to 8 non-diabetic subjects, and blood glucose and plasma insulin levels were determined at fasting, and at the postprandial times 30, 60, 90 and 120 min. Integrated insulin increments were estimated by calculation of the area under the curve. Sensory analysis of the biscuits was carried out by 36 non-diabetic panellists using a standard smiley chart containing hedonic phrases. No significant differences in the blood glucose increments were found between the control biscuit and the guar biscuits. However, all three guar biscuits produced smaller insulin rises than the control at all the postprandial times; statistically significant falls were indicated at the 60-min peak and 120-min times and for the integrated values. A linear regression model describing the relationship between integrated insulin and the dose of guar ingested is proposed. We have estimated from this model that a reduction of 209 mU/min/l in the integrated insulin can be achieved for every 1 g of guar incorporated into the biscuit. Mean hedonic scores indicated that all the guar biscuits were palatable, particularly the low-dose variety which was given a score almost identical to that of the control. A significant insulin-sparing effect in non-diabetic subjects was achieved using a palatable guar biscuit containing less than 3 g of guar flour.

Administration, Oral↗

Furfural-cysteine model reaction in food grade nonionic oil/water microemulsions for selective flavor formation.

The thermal reaction between cysteine and furfural was investigated at 65 degrees C in five-component food grade oil/water (O/W) microemulsions of R-(+)-limonene/ethanol, EtOH/water/propylene glycol, PG/Tween 60 as apart of a systematic study on the generation of aroma compounds by utilizing structured W/O and O/W fluids. The furfural-cysteine reaction led to the formation of unique aroma compounds such as 2-furfurylthiol (FFT), 2-(2-furanyl)thiazolidine (main reaction product), 2-(2-furanyl)thiazoline, and N-(2-mercaptovinyl)-2-(2-furanyl)thiazolidine. These products were determined and characterized by GC-MS. Enhancement in flavor formation is termed "microemulsion catalysis". The chemical reaction occurs preferably at the interfacial film, and therefore a pseudophase model was assumed to explain the enhanced flavor formation. The product internal composition is dictated by process conditions such as temperature, time, pH, and mainly the nature of the interface. Increasing water/PG ratio leads to a dramatic increase in the initial reaction rate (V(0)). V(0) increased linearly as a function of the aqueous phase content, which could be due to the increase in the interfacial concentration of furfural. Microemulsions offer a new reaction medium to produce selective aroma compounds and to optimize their formation.

Cyclohexenes↗