Olfactory Quality Research Articles

Evaluating olfactory function and quality of life in patients with traumatic brain injury.

Patients with traumatic brain injury (TBI) had worse olfactory quality of life (QoL) and Sino-Nasal Outcome Test-22 scores compared to a normal cohort. A worse olfactory QoL correlated with concussion symptom burden. Olfactory dysfunction among TBI patients should be addressed to improve overall outcomes.

Comparative study on the use of seasoned or unseasoned casks made of wood from different origins for the ageing of Sherry vinegar.

In the present study, the ageing process of Sherry vinegar in used (seasoned) or new casks made of chestnut, American oak, Spanish oak or French oak wood has been investigated, considering that no research has investigated whether this seasoning has a definite influence on the final composition of the aged beverage. The polyphenolic and volatile contents of the aged vinegars were determined and their sensory properties were evaluated. Different statistical tools were applied to the data collected. With respect to polyphenolic contents, ageing time was the most influential factor, followed by the seasoned-cask factor. The type of wood was only significant for gallic acid, p-hydroxybenzoic acid, methylfurfural, ethyl gallate, ferulic acid, coniferyl aldehyde and sinapaldehyde. Principal component analysis according to polyphenols did not allow the samples to be differentiated, whereas cluster analysis revealed a slight grouping trend according to ageing time and seasoning of the wood. In relation to volatile compounds, variance analysis revealed that, again, ageing time and cask-seasoning were the most significant factors, with the samples clustering according to these two parameters. Following the sensory study, a clear difference between seasoned and new cask vinegars could be established as a result of the high scores in olfactory quality obtained for those vinegars aged in new casks. This was probably because of an excess of the descriptor 'ethyl acetate' exhibited by seasoned-cask Sherry vinegars. The previous seasoning of the casks together with the ageing time conditioned the composition of the vinegars aged in casks of different botanical origin, which translated into differences at a sensory level. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Olfactory and gustatory outcomes following endoscopic transsphenoidal hypophysectomy

ObjectiveThe aim of this study was to evaluate olfactory, gustatory, and quality-of-life outcomes in patients who underwent endonasal transsphenoidal hypophysectomy.MethodsIn this prospective study, the patients were assessed subjectively using the Malay version of sQOD-NS (short questionnaire of olfactory disorders in a negative statement) and objectively using the culturally adapted Sniffin’ Sticks smell test and taste test preoperatively and 3 months postoperatively. The Sniffin’ Sticks smell test consists of odor identification, odor discrimination, and odor threshold tests. The taste test consists of different sweet, salt, sour, and bitter concentrations.ResultsTwenty patients were enrolled in the study. The study comprises 45% female and 55% male. On average patients’ ages were 49.5 years. In this study we found a significantly reduced in odor identification score (p = 0.049) post-surgery; however, there was no statistically significant difference in odor threshold, odor discrimination, and taste. The olfactory quality of life outcome based on the Malay version of sQOD-NS (p = 0.001) was significantly reduced after surgery. There was no significant difference in the Sniffin’ Sticks smell test (p < 0.178) and taste test (p < 0.425) pre-surgery and post-surgery. The tumor’s location, either sellar or suprasellar, did not influence the smell outcome of patients postoperatively (p = 0.056).ConclusionThe study showed that the endoscopic transsphenoidal technique for pituitary surgery does not pose permanent olfactory disability.

User Preferences and Dislikes Concerning Sensory Stimulation in Shopping Center Resting Areas

Studies claim that shopping centers are considered a destination because they offer ambiance, experiences, and entertainment. With the rise in online shopping, shopping centers are no longer anchored by departmental stores but with their commercial facilities. Consistent with this change, more studies are needed to improve the interior quality of side facilities like entertainment and relaxing areas in shopping centers. This study is established to understand the sensory preferences and dislikes of a group of participants in shopping center resting areas. Consistent with this target, 200 participants took part in a questionnaire survey in Antalya, Turkey. The questionnaire consisted of 5 negative and 5 positive sensory qualities of space. These qualities were defined based on the five dimensions of a sensory space as established by Barbara Erwine. Participants were asked to list the negative qualities from most disturbing to least disturbing and then positive qualities from most satisfying to least satisfying. Data from the questionnaire were analyzed using the SPSS computer program. Results showed that smell was rated as the most influential sensory quality that disturbs or satisfies participants in shopping center resting areas. Also, according to participant responses, positive and negative feelings through touching materials and surfaces were the least disturbing/satisfying quality in resting areas. This study also suggests the need for further studies on the role of smell in changing peoples’ behavior in interior spaces and establishing design considerations that can improve the olfactory quality of spaces.

Evaluation of the Olfactory Quality of Roasted Coffee Beans Using a Digital Nose.

The roasting process is one of the critical points to obtain a product of the highest quality with certain sensorial properties including the aroma of coffee. Samples of coffee beans were roasted at different thermal treatment intensities with the aim of obtaining aromatic compounds detected with an electronic device. Sensory analysis, volatile compound profiling, and electronic nose analysis were carried out. Through principal component analysis (95.8% of the total variance of the data was explained by PC1 and PC2) and partial least squares discriminant analysis (the sum of the diagonal elements gave a hit rate of 94%), it could be demonstrated that the E-nose is able to discriminate roasted coffee beans subjected to different thermal treatments. Aromatic profiling was carried out by a testing panel and volatile compounds (VOCs) for the discrimination of roasted coffee samples. Alcohols, aromatics, esters, ketones and furanone were found in higher proportions in samples at the lowest thermal treatment. The VOCs with positive attributes were 1-(4-nitrophenyl)-3-phenylamino-propenone, carboxylic acids, 2-methoxy-4-vinylphenol, and 2-phenylethyl alcohol, while the compounds with negative ones were 2-methyl-furan, 2,5-dimethyl-pyridine, 2-methyl-butanal, and 2-furfurylthiol. The PLS model allows for the quantification of the positive and negative aromas (RCV2 = 0.92) of roasted coffee by using the E-nose. Therefore, the E-nose, that is, an inexpensive and nondestructive instrument, could be a chemometric tool able to discriminate between different qualities of coffee during processing.

Real and Imagined Smellscapes.

The smellscape is the olfactory environment as perceived and understood, consisting of odours and scents from multiple smell sources. To what extent can audiovisual information evoke the smells of a real, complex, and multimodal environment? To investigate smellscape imagination, we compared results from two studies. In the first, onsite participants (N = 15) made a sensory walk through seven locations of an open-air market. In the second, online participants (N = 53) made a virtual walk through the same locations reproduced with audio and video recordings. Responses in the form of free-form verbal annotations, ratings with semantic scales, and a ‘smell wheel’, were analysed for environmental quality, smell source type and strength, and hedonic tone. The degree of association between real and imagined smellscapes was measured through canonical correlation analysis. Hedonic tone, as expressed through frequency counts of keywords in free-form annotations was significantly associated, suggesting that smell sources might generally be correctly inferred from audiovisual information, when such imagination is required. On the other hand, onsite ratings of olfactory quality were not significantly associated with online ratings of audiovisual reproductions, when participants were not specifically asked to imagine smells. We discuss findings in the light of cross-modal association, categorisation, and memory recall of smells.

Multimodal

Multimodal

E-nose coupled with an artificial neural network to detection of fraud in pure and industrial fruit juices

ABSTRACT Consumer demands for fresh foods with desired sensory properties. Lack of easy, cheap, and nondestructive methods to control the quality of fruit juices is one of the main challenges in the beverage industry. The present study has examined two types of natural and industrial juices. Machine olfaction with 9 metal oxide semiconductor (MOS) sensors was used for the experiments. Sensor response patterns were analyzed using artificial neural networks (ANN). PCR method was used to evaluate the discrimination power of the sensors. According to the results, the discrimination power of the sensors used in the electronic nose sensor array was determined, three of which were removed due to improper response power. The proposed method can be used to select the minimum and most effective number of MOS gas sensors to construct an electronic nose system to control the olfactory quality of different foods. The use of a minimum number of sensors reduces the cost of constructing an electronic nose system, decreases the volume of the processor data input, and consequently increases the classification accuracy. Therefore, the MOS-based electronic nose combined with the ANN can be an effective and highly efficient tool in the fast and nondestructive classification of pure and industrial fruit juices.

Comparison of Olfactory Quality in Patients with Sinus and Nasal Polyposis Before and After Polypectomy

Comparison of Olfactory Quality in Patients with Sinus and Nasal Polyposis Before and After Polypectomy

Total Synthesis of (−)‐Rotundone and (−)‐epi‐Rotundone from Monoterpene Precursors

AbstractThe first total synthesis of (−)‐rotundone has been accomplished from (+)‐(R)‐limonene and therefore for the first time from an unrelated monoterpene instead of modifying structurally closely related sesquiterpene precursors such as α‐guaiene. Challenges such as intermediates with stereocenters prone to epimerization by enolization were overcome by designing a β‐methyl‐keto route starting from (+)‐(R)‐limonene which finally gave (−)‐rotundone by Nazarov cyclization of a precursor 13a. Diastereomer (−)‐epi‐rotundone was separated from (−)‐rotundone chromatographically. An alternative route from rac‐citronellal provided a diastereomer mixture of racemic Nazarov precursor 13 through a TRIP‐catalyzed intramolecular aldolization, thus indicating that the Nazarov cyclization precursor 13a is in principle accessible from (−)‐(S)‐citronellal. The 11‐step synthesis from (+)‐(R)‐limonene with ca. 1 % overall yield confirmed the absolute configuration of (−)‐rotundone and provided samples of good olfactory quality.

A Systematic Framework for Olfactory Bulb Signal Transformations.

We describe an integrated theory of olfactory systems operation that incorporates experimental findings across scales, stages, and methods of analysis into a common framework. In particular, we consider the multiple stages of olfactory signal processing as a collective system, in which each stage samples selectively from its antecedents. We propose that, following the signal conditioning operations of the nasal epithelium and glomerular-layer circuitry, the plastic external plexiform layer of the olfactory bulb effects a process of category learning—the basis for extracting meaningful, quasi-discrete odor representations from the metric space of undifferentiated olfactory quality. Moreover, this early categorization process also resolves the foundational problem of how odors of interest can be recognized in the presence of strong competitive interference from simultaneously encountered background odorants. This problem is fundamentally constraining on early-stage olfactory encoding strategies and must be resolved if these strategies and their underlying mechanisms are to be understood. Multiscale general theories of olfactory systems operation are essential in order to leverage the analytical advantages of engineered approaches together with our expanding capacity to interrogate biological systems.

A Study on the Effects of Polite Yawning Technique on Rehabilitation of Olfaction After Total Laryngectomy

Background: Laryngeal cancer is one of the most common head and neck cancers for which total laryngectomy is the preferred treatment in advanced stages. Major disabilities of this surgical procedure include loss of voice and nasal function, swallowing difficulties, and psychological consequences. Objectives: This study aimed to investigate the effect of the Polite Yawning technique on olfactory quality in patients undergoing total laryngectomy. Methods: In this cross-sectional study, after total laryngectomy, the patients with olfactory dysfunction were enrolled and the quality of olfaction was evaluated by the Quick Odor Detection test before and after receiving the Nasal Airflow Inducing Maneuver technique training. Statistical analysis was performed using SPSS 21 software by the Wilcoxon or McNemar’s test. The significance level was considered for P ≤ 0.05. Results: A total of 40 patients were evaluated. The mean age was 55.98 ± 6.27 years. Eighty-five percent of the patients were male (n = 34). The difficulty score in learning maneuvering was 2.5 ± 1.3, and 90% had no problem with learning it. Before maneuver, none of the patients had normal olfaction and had hyposmia mostly (n = 32, 80%). Immediately after the maneuver, there was a sensation of smell in all patients and the rate of hyposmia in patients was reduced to 65% (P = 0.008). Normal olfactory status was reported in half of the patients one month after the maneuver (21 patients, 52.5%, P = 0.0001), and there was a sense of smell in all patients (P = 0.0001). Conclusions: The results proved that olfactory quality can be rehabilitated after laryngectomy by the nasal airflow-inducing maneuver (the “Polite Yawning” technique). It is a patient-friendly method; however, a single training session is probably insufficient and most patients may need more training sessions.

Physicochemical, aromatic and sensory properties of the ‘Riesling Italico’ wines fermented with Saccharomyces and non-Saccharomyces yeasts

ABSTRACT: The sensory quality of wines is affected by the compounds produced by the action of the yeasts used in alcoholic fermentation. This work aimed at assessing the physicochemical, aromatic and sensory properties of the ‘Riesling Italico’ white wines produced by using the Saccharomyces and non-Saccharomyces yeasts. The yeasts S. cerevisiae, S. cerevisiae cerevisiae, S. bayanus, Torulaspora delbrueckii and Metschnikowia pulcherrima were inoculated individually into the must. For 10 days, the alcohol was left to ferment in 7 L carboys in triplicate, at 15º C temperature. The standard physicochemical analyses were done and the quality of the wines was determined. The volatile compounds were identified and quantitative descriptive sensory analyses were performed. All the yeasts produced wines with the characteristic alcohol, volatile acidity and residual sugar content as stipulated by the Brazilian legislation. The T. delbrueckii yeast produced high-content phenylethyl acetate, isoamyl acetate and ethyl decanoate wines, of superior olfactory quality and sensory rating.

Olfactory change detection

The human olfactory system is characterized by poor temporal and spatial resolution. When determining changes in the environment, humans rather rely on visual than on olfactory information. Against this background, we developed a test in order to investigate the human capacity to detect changes in the olfactory environment and to determine potential modulators of olfactory change detection.Participants consecutively received four odors (2 odor qualities in 2 concentrations each) which were presented via a computer-controlled olfactometer. The participants’ task was to react as soon as they perceived a change of the odor. For control purpose, the same paradigm was also presented with visual instead of olfactory stimuli. A total of 83 healthy participants (aged 18–34 years, 50 women) were included; all of them were screened for attention, olfactory function, chemical sensitivity and the subjective importance of the sense of smell.While visual changes were detected above chance by all participants, olfactory changes were reliably detected by only 24% of the participants. Those were characterized by high subjective importance of olfaction and low chemical sensitivity. Across all participants, changes of olfactory quality were detected more frequently than changes of olfactory concentration.These results suggest that olfaction is imprecise in guiding environmental change detection and may help to explain why humans typically rate the importance of vision higher than the importance of olfaction.

Enzyme-Catalysed Conversion of Atranol and Derivatives into Dimeric Hydrosoluble Materials: Application to the Preparation of a Low-Atranol Oakmoss Absolute

Oakmoss absolute, a solvent extract from Evernia prunastri, is a valuable fragrance ingredient widely used in fine fragrance for almost two centuries. Some minor components of oakmoss absolute, such as atranol and chloroatranol, are attested contact allergens and their presence in fragrance and cosmetic products should be as low as possible. In this context, we have developed an enzyme-based protocol upon which these undesirable molecules are converted in a hydrosoluble dimeric material, and thus easily separated from the absolute by liquid–liquid extraction. Analytical and sensory analyses were performed to confirm the specificity of the process, the absence of alteration of the olfactory quality of the absolute, and the final titles of atranol and chloroatranol, which eventually were observed in the ppm range. This highly sustainable process is a viable alternative to conventional time-, energy-, and manpower-consuming techniques to produce very low-atranol oakmoss absolute.

Smelling matter

While the objects of olfaction are intuitively individuated by reference to the ordinary objects from which they arise, this intuition does not accurately capture the complex nature of smells. Smells are neither ordinary three-dimensional objects, nor Platonic vapors, nor odors. Rather, smells are the molecular structures of chemical compounds within odor plumes. Molecular Structure Theory is offered as an account of smells, which can explain the nature of the external object of olfactory perception, what we experience as olfactory objects, and what determines the olfactory quality of smells by which we can demarcate the spatiotemporal boundaries of smells.

Dissociated neural representations induced by complex and simple odorant molecules

An important challenge in olfaction research is to understand how percepts relate to the molecular structure of stimuli. Previous psychophysical studies showed that, whereas structurally simple odorant molecules evoked a more uniform qualitative perception as revealed by the use of a small number of labels to describe their olfactory quality, more complex odorants evoked a larger variety of olfactory qualities, reflecting a more heterogeneous qualitative perception. The present study examined how this influence of odorant molecular complexity on perception is reflected in the human brain. To this end, participants were stimulated with structurally simple and complex odorant molecules and their brain responses were assessed by functional magnetic resonance imaging (fMRI). Low- and high-complexity odorants were judged to have the same intensity, pleasantness and familiarity (p>0.05 in all cases), whereas complex odorants induced more quality labels than simple odorants (p<0.02) as expected. Imaging analysis of complex vs. simple odorants revealed significant activation in dorsal anterior cingulate gyrus, but not in primary olfactory areas. Taken together, these findings suggest dissociated neural representations of uniform and heterogeneous olfactory perception, highlighting for the first time the impact of odorant complexity on activity of the cingulate gyrus.

Crossmodal effect of music and odor pleasantness on olfactory quality perception.

Previous research has demonstrated that ratings of the perceived pleasantness and quality of odors can be modulated by auditory stimuli presented at around the same time. Here, we extend these results by assessing whether the hedonic congruence between odor and sound stimuli can modulate the perception of odor intensity, pleasantness, and quality in untrained participants. Unexpectedly, our results reveal that broadband white noise, which was rated as unpleasant in a follow-up experiment, actually had a more pronounced effect on participants’ odor ratings than either the consonant or dissonant musical selections. In particular, participants rated the six smells used as being less pleasant and less sweet when they happened to be listening to white noise, as compared to any one of the other music conditions. What is more, these results also add evidence to support the existence of a close relationship between an odor’s hedonic character and the perception of odor quality. So, for example, independent of the sound condition, pleasant odors were rated as sweeter, less dry, and brighter than the unpleasant odors. These results are discussed in terms of their implications for the understanding of crossmodal correspondences between olfactory and auditory stimuli.

Quality-space theory in olfaction

Quality-space theory (QST) explains the nature of the mental qualities distinctive of perceptual states by appeal to their role in perceiving. QST is typically described in terms of the mental qualities that pertain to color. Here we apply QST to the olfactory modalities. Olfaction is in various respects more complex than vision, and so provides a useful test case for QST. To determine whether QST can deal with the challenges olfaction presents, we show how a quality space (QS) could be constructed relying on olfactory perceptible properties and the olfactory mental qualities then defined by appeal to that QS of olfactory perceptible properties. We also consider how to delimit the olfactory QS from other modalities. We further apply QST to the role that experience plays in refining our olfactory discriminative abilities and the occurrence of olfactory mental qualities in non-conscious olfactory states. QST is shown to be fully applicable to and useful for understanding the complex domain of olfaction.

Extensive Environmental-Monitoring Project Relies on Integration of Several Networks

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 156294, ’Innovative Environmental Monitoring for Upstream Onshore Installation,’ by Paolo Carnevale, SPE, and Silvia Di Croce, Eni, prepared for the 2012 SPE/APPEA International Conference on Health, Safety, and Environment in Oil and Gas Exploration and Production, Perth, Australia, 11-13 September. The paper has not been peer reviewed. A comprehensive environmental-monitoring project in the Agri Valley in southern Italy has been developed to ensure continuous management of the environmental effects of Eni’s oil treatment center there. This project is able to control the environmental effects of exploration and production in a large area around the plant (100 km2). It is characterized by a complete integration of several networks, stations, and systems used to monitor simultaneously air quality, noise, odorous emissions in terms of olfactory nuisance, groundwater and soil quality, ecosystems status, and ecological biodiversity. Introduction The area where the environmental-monitoring project was developed is characterized by sites that have community-level protection, especially areas protected because of national parks, widespread woods, rivers and streams of high quality, and springs and ground water of great regional and national importance for the production of safe drinking water. Eni’s oil treatment center in this territory collects the production from 24 oil wells, amounting to approximately 104,000 BOPD (Fig. 1). The environmental-monitoring plan consists of environmental-monitoring networks on more than 100 km2 at altitudes between 600 and 900 m. The system includes monitoring networks relevant to the following environmental variables: Air quality Biosystems Bad odors Noise Microseismicity Ecosystem Air Quality The network consists of four monitoring units placed 2.3–4.8 km from the oil center. The sites were chosen according to a model that predicted the spread of emissions from the oil center. The air-quality-monitoring stations were installed outside the plant to continuously identify the effects that production activities have on the quality of the air and to provide operational warnings to avoid any negative effect on the surrounding territory. Each unit is provided with computerized instruments, allowing continuous monitoring of the levels of carbon mon-oxide, hydrogen sulfide, sulfur dioxide, ozone, nitrogen oxides, benzene, toluene, xylene, methane, nonmethane gases, volatile organic compounds, polycyclic aromatic hydrocarbons, and radon, and monitoring of meteorological standards (e.g., wind speed and direction, rainfall levels, humidity, temperature). The data received continuously from the monitoring units are reported in real time on the Web and in the control room of the plant and are compared continuously with information on pollution standards taken from the chimneys of the oil center.