Flavor Mixtures Research Articles

Evaluation of mixtures of flavor chemicals in a 90-day nose-only exposures in sprague-dawley rats.

One of the challenges to using some flavor chemicals in aerosol products is the lack of route of administration specific toxicology data. Flavor chemicals (88) were divided into four different flavor mixtures based upon chemical compatibility and evaluated in 2-week dose-range-finding and subsequent 90-day nose-only rodent inhalation studies (OECD 413 and GLP compliant). Sprague-Dawley rats were exposed to vehicle control or one of three increasing concentrations of each flavor mixture. In the dose-range-range-finding studies, exposure to flavor mixture four resulted in adverse nasal histopathology in female rats at the high dose, resulting in this flavor mixture not being evaluated in a 90-day study. In the 90-day studies daily exposures to the three flavor mixtures did not induce biologically meaningful adverse effects (food consumption, body weights, respiratory physiology, serum chemistry, hematology, coagulation, urinalysis, bronchoalveolar lavage fluid analysis and terminal organ weights). All histopathology findings were observed in both vehicle control and flavor mixture exposed animals, with similar incidences and/or severities, and therefore were not considered flavor mixture related. Based on the absence of adverse effects, the no-observed-adverse-effect concentration for each 90-day inhalation study was the highest dose tested, 2.5mg/L of the aerosolized high dose of the three flavor mixtures.

Cerveza artesanal con inclusión de maíz, pulpa de piña (Ananas comosus) y esencia de coco (Cocos nucifera): Propiedades tecnológicas y sensoriales

Craft beer is of vital importance because it is brewed with natural ingredients and has been known worldwide for its variety of flavour and excellent quality since ancient times. Therefore, the aim of this research work was to brew craft beer with the inclusion of corn, pineapple pulp (A. comosus) and coconut essence (C. nucifera) and its evaluation of technological and sensory properties. An A*B+1 factorial design was used, in which cereal mixtures (barley and maize) and flavour mixtures (pineapple pulp and coconut essence) were evaluated. The results showed a significant difference (p < 0.05) between the means of the treatments, determining that GT1 (75% barley + 25% maize + 2.5% pineapple pulp + 1% coconut essence), presented similar values to the control treatment with a total acidity of 0.20%; alcohol content of 4.95% and a colour by spectrophotometry of 7.05 SRM. In addition, it presented the best sensory profiles, according to the categories evaluated, with a mild aroma; moderate bitter taste; golden colouring characteristic of the sample and a higher level of acceptability. It is necessary to mention that the use of new raw materials, such as maize, of which only 20% is used in Ecuador for the food industry, by including it in the formulation of beers, increases the production and consumption of this grain, thus promoting new alternatives that contribute to the country's socio-economic sector.

The role of nonspecific proteolysis in the development of alterative changes in lung tissue when using electronic cigarettes

In recent years, the number of electronic cigarettes (ES) users has been growing steadily around the world. ES heat and vaporize components of a mixture of propylene glycol, vegetable glycerin, nicotine, and flavors. Reports of severe forms of lung injury caused by the use of ES, some of which have resulted in death, urge studying the pathogenetic mechanisms of such complications. One of the mechanisms is the activation of nonspecific proteolysis accompanied by the destruction of connective tissue components of the blood-air barrier.Aim of the study. To study the dynamics of the proteinase-inhibitor system indicators and its role in the morphological changes of lung tissue in experimental modeling of the effects of ES.Methods. Experimental studies were performed in 24 white male Wistar rats weighing 160 – 180 g. ES use of was simulated by intermittent exposure to smoke mixture vapors using a POD system connected to a two-channel compressor.Results. Analysis of the state of the nonspecific proteinase inhibitory system in rat broncho-alveolar lavage and blood serum and the results of morphological studies indicate activation of trypsin-like proteinases and depletion of the local antitryptic potential, leading to biochemical changes with subsequent structural changes in lung tissue. The latter are characterized by congestion, leukocyte infiltration, and stromal proliferation. In addition, exposure to nicotine-containing mixtures has been shown to affect the proteinase inhibitory system and blood serum composition, which is associated with a compensatory increase in antitrypsin activity.Conclusion. The results of the study indicate the activation of trypsin-like proteinases in broncho-alveolar lavage, which have a damaging effect on lung tissue, leading to disturbances in tissue hemodynamics, extravasation of leukocytes, remodeling and thickening of the blood-air barrier.

Charakterisierung von Fermentationsaromen mittels gaschromatographischer Techniken

Charakterisierung von Fermentationsaromen mittels gaschromatographischer Techniken

Identification of Quality of Complex Flavour Mixtures Used in Meat Industry

A húsfeldolgozó iparban nagy jelentőséggel bírnak a többfunkciós komplex fűszerkeverékek, amelyek egyszerűsítik és felgyorsítják az élelmiszer-előállítást. A kutatás célja egy fűszerkeverék-előállító vállalat által gyártott termékek minőségének meghatározása volt. Megállapították, hogy az érzékszervi, fizikai és kémiai paraméterek tekintetében a fokhagymát és grillfűszereket tartalmazó készítmény összetétele megfelel az előírásoknak. A fokhagymakészítményben a gyártó által nem bejelentett étkezési só jelenlétét mutattuk ki. Élelmi rost az összes vizsgált fűszerkeverékben kimutatható mennyiségben volt jelen. A fokhagymakészítmény Al-, Li-, Mg-, P-, Si-, Sr-, Te-, tartalma, illetve megnövekedett Mo-, Ti-, V- és W-tartalma miatt különbözött a többi komplex készítménytől. A második számú keverék viszonylag nagy mennyiségben tartalmazott Ca-ot, Cr-ot és Fe-at, de kimutatható mennyiségben nem tartalmazott a gyártó által az E551 adalékként bejelentett Si-ot. A grillfűszer összetétele a Mn, Na és Zn magas tartalma miatt tűnt ki, egy másik aroma-keverék pedig a magas Cu-tartalom miatt. Meg kell jegyezni, hogy az egyik fűszerkeverékben E627 és E631 ízfokozókat, míg egy grillkeverékben pedig E450 stabilizátort és emulgeálószert találtunk. Számos szakértő szerint ezek az összetevők veszélyt jelentenek az emberi szervezetre, mivel bél- és gyomorpanaszokat okozhatnak. Ebben a tekintetben meg kell érteni, hogy mely élelmiszer-adalékanyagokat kell kizárni az ember étrendjéből, melyek különösen veszélyesek, és melyeket lehet a húskészítmények összetevőként biztonságosan fogyasztani időről időre kis mennyiségben.

Identification of Quality of Complex Flavour Mixtures Used in Meat Industry

Multifunctional complex flavour mixtures, which simplify and speed up food production, are of great importance in the meat processing industry. The aim of the research was to identify the quality of complex food spice mixes prepared by a producer. It was found that the compositions of the grill spice mix met the regulations in terms of organoleptic, physical, and chemical parameters. The garlic mixture sample revealed the presence of edible salt, not declared by the manufacturer. Dietary fiber was present in all the mixes under study. Garlic 1:6 sample differed from the other complex additives by the increased content of Al, Li, Mg, P, Si, Sr, Te, as well as the presence of Mo, Ti, V, and W. The ‘grill spice mix’ had relatively high amounts of Ca, Cr, and Fe, but did not contain detectable amount of Si, declared by the manufacturer as part of E551. The composition of the grill spice mix stood out because of the high content of Mn, Na, and Zn, an aroma mixture – Cu. It should be noted that E627 and E631 flavor enhancers were found in an aroma mixture, whereas E450 stabilizer and emulsifier was found in a grill aroma mixture. According to a number of experts, these components pose a threat to the human body as they can cause intestinal and stomach disorders. In this regard, it is necessary to understand which food additives need to be excluded from a person’s diet, which are especially dangerous, and which are safe to consume from time to time in small quantities as part of meat products.

Introduction of Flavor Chemical Eugenol Attenuating the Synergistic Toxicological Interactions of Flavor Mixtures.

The flavor chemicals benzyl alcohol (BEA), phenylethanol (PHA), and cinnamaldehyde (CID) and their binary mixtures have high toxicity sensitivity to the lethal endpoint of Caenorhabditis elegans. Some binary flavor mixtures even have synergistic toxicological interactions. Eugenol (EUG) is closely related to human life and has many special nonlethal effects on organisms. The effect of its introduction on the combined toxicities of flavor mixtures is worth studying. We introduced EUG into three binary (BEA-PHA, BEA-CID, and PHA-CID) and one ternary (BEA-PHA-CID) flavor mixture systems. Five representative mixture rays were selected from each of the four mixture systems using the uniform design ray (UD-Ray) method. The lethal toxicity of each mixture ray to C. elegans was measured at three different exposure volumes (100, 200, and 400 μL), and a dose–effect model was established. The new parameter iSPAN was used to quantitatively characterize the toxicity sensitivity of each chemical and mixture ray. The toxicological interaction of each mixture was evaluated by the toxicological interaction heatmap based on the combination index (CI). It can be seen that all flavor chemicals and their ternary and quaternary mixture rays have high iSPANs, and the highest value is 16.160 (BEA-PHA-CID-EUG-R1 at 400 μL). According to the heatmap and CI, the introduction of EUG attenuates the synergistic toxicological interactions of flavor mixtures, leading to the transformation ofsynergistic interactions in flavor mixtures into additive action and even antagonistic interaction, and the CI value of the antagonistic interaction is up to 1.8494 (BEA-CID-EUG-R4 at 400 μL).

Assessment of inhalation toxicity of cigarette smoke and aerosols from flavor mixtures: 5-week study in A/J mice.

Most flavors used in e‐liquids are generally recognized as safe for oral consumption, but their potential effects when inhaled are not well characterized. In vivo inhalation studies of flavor ingredients in e‐liquids are scarce. A structure‐based grouping approach was used to select 38 flavor group representatives (FGR) on the basis of known and in silico‐predicted toxicological data. These FGRs were combined to create prototype e‐liquid formulations and tested against cigarette smoke (CS) in a 5‐week inhalation study.Female A/J mice were whole‐body exposed for 6 h/day, 5 days/week, for 5 weeks to air, mainstream CS, or aerosols from (1) test formulations containing propylene glycol (PG), vegetable glycerol (VG), nicotine (N; 2% w/w), and flavor (F) mixtures at low (4.6% w/w), medium (9.3% w/w), or high (18.6% w/w) concentration or (2) base formulation (PG/VG/N). Male A/J mice were exposed to air, PG/VG/N, or PG/VG/N/F‐high under the same exposure regimen. There were no significant mortality or in‐life clinical findings in the treatment groups, with only transient weight loss during the early exposure adaptation period. While exposure to flavor aerosols did not cause notable lung inflammation, it caused only minimal adaptive changes in the larynx and nasal epithelia. In contrast, exposure to CS resulted in lung inflammation and moderate‐to‐severe changes in the epithelia of the nose, larynx, and trachea. In summary, the study evaluates an approach for assessing the inhalation toxicity potential of flavor mixtures, thereby informing the selection of flavor exposure concentrations (up to 18.6%) for a future chronic inhalation study.

Deep Learning-Based Method for Compound Identification in NMR Spectra of Mixtures.

Nuclear magnetic resonance (NMR) spectroscopy is highly unbiased and reproducible, which provides us a powerful tool to analyze mixtures consisting of small molecules. However, the compound identification in NMR spectra of mixtures is highly challenging because of chemical shift variations of the same compound in different mixtures and peak overlapping among molecules. Here, we present a pseudo-Siamese convolutional neural network method (pSCNN) to identify compounds in mixtures for NMR spectroscopy. A data augmentation method was implemented for the superposition of several NMR spectra sampled from a spectral database with random noises. The augmented dataset was split and used to train, validate and test the pSCNN model. Two experimental NMR datasets (flavor mixtures and additional flavor mixture) were acquired to benchmark its performance in real applications. The results show that the proposed method can achieve good performances in the augmented test set (ACC = 99.80%, TPR = 99.70% and FPR = 0.10%), the flavor mixtures dataset (ACC = 97.62%, TPR = 96.44% and FPR = 2.29%) and the additional flavor mixture dataset (ACC = 91.67%, TPR = 100.00% and FPR = 10.53%). We have demonstrated that the translational invariance of convolutional neural networks can solve the chemical shift variation problem in NMR spectra. In summary, pSCNN is an off-the-shelf method to identify compounds in mixtures for NMR spectroscopy because of its accuracy in compound identification and robustness to chemical shift variation.

Zygosaccharomyces rouxii is the predominant species responsible for the spoilage of the mix base for ice cream and ethanol is the best inhibitor tested

A mix base for ice cream (MBIC) is used to produce artisanal or industrial ice creams and desserts and consists of a mixture of different ingredients, including sugar, egg yolk, natural flavors, starch and milk proteins. MBICs, which have chemical-physical characteristics that include a pH of 5.61 and an activity water (Aw) less than or equal to 0.822, are packaged in tin boxes and stored at ambient temperature. Despite the low Aw, MBIC can support osmotolerant and osmophilic yeast growth. The aim of our work was to study the behavior of Zygosaccharomyces rouxii, the main microorganisms responsible of MBIC spoilage, either in the vivo or in a model system in order to inhibit its growth by the selection of antimicrobial agents. Different osmotolerant yeasts belonging to the genus Zygosaccharomyces were isolated and identified from spoiled and unspoiled lots of MBICs. In particular, Z. rouxii was the predominant species responsible for the spoilage, which depended on the high temperature of storage (>20 °C) and was highlighted by the presence of alcohol, esters, acids and gas (CO2), which blew open the tin boxes. To stop spoilage, different antimicrobial compounds were tested: sulfur dioxide, sorbic and benzoic acids and ethanol. However, only 2% v/v ethanol was required to achieve the total inhibition of the Z. rouxii cocktails tested in this work. The use of other antimicrobials cannot be recommended because they were not able to stop yeast spoilage and changed the color and flavor of the products. Conversely, the use of ethanol is suggested because of its extreme effectiveness against osmotolerant yeasts, and the added amount was less than or equal to the taste threshold limit. The MBICs, treated with ethanol, were stable till the end of their shelf-life (6 months).

Analysis of the Ability to Produce Pleasant Aromas on Sour Whey and Buttermilk By-Products by Mold Galactomyces geotrichum: Identification of Key Odorants.

Currently, there is a growing demand for flavorings, especially of natural origin. It is worth paying attention to the biotechnological processes of flavor production, characterized by simplicity, high efficiency and relatively low cost. In this study, we analyzed the ability of the Galac tomyces geotrichum mold to transform by-products of the dairy industry: sour whey and buttermilk to complex flavour mixtures with pleasant, honey-rose aroma. Furthermore, the aroma complexity of the fermentation product has been carefully identified applying a sensomic approach involving the use of gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and stable isotope dilution assay (SIDA) to identify and quantify aroma compounds. Based on the calculation of odor activity value (OAV), 13 key aroma compounds were present in both tested variants. The highest OAVs were found for phenylacetaldehyde (honey-like) in the buttermilk variant (912) and 2-phenylethanol (rose-like) in the sour whey variant (524). High values of this indicator were also recorded for phenylacetaldehyde (319) and 3-methyl-1-butanol with a fruity aroma (149) in the sour whey culture. The other compounds identified are 3-methylbutanal (malty), 2,3-butanedione (cheesy), isovaleric acid (cheesy), 3-(methylthio)-propanal (boiled potato), butanoic acid (vinegar), (E)-2-nonenal (fatty), ethyl furaneol (burnt sugar), dimethyl trisulfide (cabbage), and acetic acid (vinegar).

Electronic cigarettes: Genetic and epigenetic impact (Review)

Electronic cigarettes (ECIGs) are electronic devices that heat and vaporize a solution that usually contains a mixture of glycerol, propylene glycol, water, flavors and various concentrations of nicotine. ECIGs have 3 key components: A power source, a cartridge containing an atomizer along with a liquid solution and a mouthpiece. The solution (often known as e‑liquid or e‑juice) is heated into an aerosol inhaled by the user. Smoking conventional cigarettes is considered a determinant factor in the development of chronic respiratory diseases, cardiovascular diseases, cancers, and reproductive system dysfunctions. Conventional smoking also causes genome damage and alteration of the transcriptome, due to the amounts of noxious substances emitted during the combustion of these products. Recently, cigarette consumers have begun to use ECIGs as a replacement or substitute practice to help them quit smoking. In addition, an increase in the use of ECIGs and similar devices by young individuals has been reported, which is unsurprising due to the unregulated distribution and sale of these products. The present review article describes and discusses the impact and the noxious effects of substances in ECIGs and other nicotine administration systems on DNA structure, gene expression profile, and epigenetic modification, focusing on the respiratory system and embryonic development.

Exploring in vitro to in vivo extrapolation for exposure and health impacts of e-cigarette flavor mixtures

In vitro to in vivo extrapolation (IVIVE) leverages in vitro biological activities to predict corresponding in vivo exposures, therefore potentially reducing the need for animal safety testing that are traditionally performed to support the hazard and risk assessment. Interpretation of IVIVE predictions are affected by various factors including the model type, exposure route and kinetic assumptions for the test article, and choice of in vitro assay(s) that are relevant to clinical outcomes. Exposure scenarios are further complicated for mixtures where the in vitro activity may stem from one or more components in the mixture. In this study, we used electronic cigarette (EC) aerosols, a complex mixture, to explore impacts of these factors on the use of IVIVE in hazard identification, using open-source pharmacokinetic models of varying complexity and publicly available data. Results suggest in vitro assay selection has a greater impact on exposure estimates than modeling approaches. Using cytotoxicity assays, high exposure estimates (>1000 EC cartridges (pods) or > 700 mL EC liquid per day) would be needed to obtain the in vivo plasma levels that are corresponding to in vitro assay data, suggesting acute toxicity would be unlikely in typical usage scenarios. When mechanistic (Tox21) assays were used, the exposure estimates were much lower for the low end, but the range of exposure estimate became wider across modeling approaches. These proof-of-concept results highlight challenges and complexities in IVIVE for mixtures.

Effect of the rs2890498 polymorphism of the OBPIIa gene on the human ability to smell single molecules

Most odors of foods and drinks are mixtures of molecules. By means of the coupled Gas Chromatography-Olfactometry (GC-O) technique, single components of flavor mixtures can be separated, identified and verbally evaluated by subjects. The number of single molecules smelled by subjects during GC-O analysis (i.e., the number of odor-active compounds) was previously found to be linearly correlated with odor Threshold (T) score. Using the “Sniffin' Sticks” test, the same subjects were classified as normosmic or hyposmic. Hydrophobic odorants are captured and transported through the mucus layer by the odorant binding proteins (OBPs), particularly expressed in the olfactory cleft and associated with the olfactory function. In this study, subjects were genotyped for the rs2590498 (A/G) polymorphism of the OBPIIa gene, whose major allele A is associated with a higher olfactory sensitivity as compared to the minor allele G. One-way ANOVA showed a significant effect of the genotype of the OBPIIa locus on the: a) T score; b) number of odor-active compounds smelled; c) intensity perceived when sniffing the complex odor of banana. In conclusion, the threshold olfactory performance, but also the individual ability to smell single molecules, can be attributed, partly at least, to the rs2590498 polymorphism of the OBPIIa gene.

E-Liquid Containing a Mixture of Coconut, Vanilla, and Cookie Flavors Causes Cellular Senescence and Dysregulated Repair in Pulmonary Fibroblasts: Implications on Premature Aging.

Electronic cigarette (e-cig) usage has risen dramatically worldwide over the past decade. While they are touted as a safe alternative to cigarettes, recent studies indicate that high levels of nicotine and flavoring chemicals present in e-cigs may still cause adverse health effects. We hypothesized that an e-liquid containing a mixture of tobacco, coconut, vanilla, and cookie flavors would induce senescence and disrupt wound healing processes in pulmonary fibroblasts. To test this hypothesis, we exposed pulmonary fibroblasts (HFL-1) to e-liquid at varying doses and assessed cytotoxicity, inflammation, senescence, and myofibroblast differentiation. We found that e-liquid exposure caused cytotoxicity, which was accompanied by an increase in IL-8 release in the conditioned media. E-liquid exposure resulted in elevated senescence-associated beta-galactosidase (SA-β-gal) activity. Transforming growth factor-β1 (TGF-β1) induced myofibroblast differentiation was inhibited by e-liquid exposure, resulting in decreased α-smooth muscle actin and fibronectin protein levels. Together, our data suggest that an e-liquid containing a mixture of flavors induces inflammation, senescence and dysregulated wound healing responses.

Urea-Based Low-Molecular-Weight Pseudopeptidic Organogelators for the Encapsulation and Slow Release of (R)-Limonene.

Low-molecular-weight compounds containing alkylurea fragments attached to the amino end of different miminalistic pseudopeptidic structures have been shown to be excellent organogelators in a variety of organic solvents and liquid organic compounds of different nature. The formation of gels in this work is defined through rheological measurements for those cases where G' > G''. Both the topology and the symmetry of the corresponding urea compounds play a role in defining their organogelator behavior. This can also be tuned by the presence of additional supramolecular guests, as is the case for suberic acid. These compounds also achieve the gelation of relevant active substances such as terpene natural oils and complex mixtures of flavors and fragrances. This provides a simple and mass-efficient supramolecular system for the quantitative encapsulation of active substances, without the need for any additional solvent or complex processes, and their consequent controlled release.

Evaluation of toxicity of aerosols from flavored e-liquids in Sprague\u2013Dawley rats in a 90-day OECD inhalation study, complemented by transcriptomics analysis

The use of flavoring substances is an important element in the development of reduced-risk products for adult smokers to increase product acceptance and encourage switching from cigarettes. In a first step towards characterizing the sub-chronic inhalation toxicity of neat flavoring substances, a study was conducted using a mixture of the substances in a base solution of e-liquid, where the standard toxicological endpoints of the nebulized aerosols were supplemented with transcriptomics analysis. The flavor mixture was produced by grouping 178 flavors into 26 distinct chemical groups based on structural similarities and potential metabolic and biological effects. Flavoring substances predicted to show the highest toxicological effect from each group were selected as the flavor group representatives (FGR). Following Organization for Economic Cooperation and Development Testing Guideline 413, rats were exposed to three concentrations of the FGR mixture in an e-liquid composed of nicotine (23 µg/L), propylene glycol (1520 µg/L), and vegetable glycerin (1890 µg/L), while non-flavored and no-nicotine mixtures were included as references to identify potential additive or synergistic effects between nicotine and the flavoring substances. The results indicated that the inhalation of an e-liquid containing the mixture of FGRs caused very minimal local and systemic toxic effects. In particular, there were no remarkable clinical (in-life) observations in flavored e-liquid-exposed rats. The biological effects related to exposure to the mixture of neat FGRs were limited and mainly nicotine-mediated, including changes in hematological and blood chemistry parameters and organ weight. These results indicate no significant additive biological changes following inhalation exposure to the nebulized FGR mixture above the nicotine effects measured in this sub-chronic inhalation study. In a subsequent study, e-liquids with FGR mixtures will be aerosolized by thermal treatment and assessed for toxicity.

Estetica aromatica

In this paper, we aim to show how flavors – specifically food flavors – and the atmospheres they help create have a strong sociopolitical value. Smells are here dealt with as vector elements inscribed in the collective space; they, on the one hand, affect the way in which refusal or acceptance occur and, on the other, mold perceptual and fruition model. By «aromatic aesthetics», we refer to the dimension in which smells are related to peculiar atmospheric policies. Stemming from this framework, we present the notions of sterilization, deodorization, and flavoring anew in the light of bodily, sensory and cognitive effects on the individual and on the relations with the surrounding world, particularly with food. The concoction of synthetic flavor mixtures and its subsequent perception cause atmospheric manipulations able to affect both collectively and individually the sense of smell. In contrast to this aggressive and standardizing practice, we try to outline an alternative approach based on the idea of engagement aiming to contribute to a complete ecological aesthetics.

Association between human olfactory performance and ability to detect single compounds in complex chemical mixtures.

Humans can accurately discern thousands of odorants, although there is a considerable inter-individual variability. Individuals can be classified as normosmic, hyposmic or anosmic, depending on their olfactory sensitivity or blindness. In this research we studied the olfactory sensitivity to banana head-space as a complex odor mixture in a group of 53 subjects classified for their olfactory status, by means of the "Sniffin' Sticks" extended test. Using the coupled Gas Chromatography-Mass Spectrometry/ Olfactometry (GC–MS/O) technique, the single components of the banana flavor mixture were separated, identified and verbally evaluated by each subject. For each compound both the “odor type” (i.e., odor quality: fruity, floral, green, etc.) and “odor descriptor” (i.e., name used by subjects for odor identification) were reported, so that we could identify molecules that were defined as smelling of banana. The results show that: (a) the threshold olfactory performance is linearly correlated with the number of odor-active compounds (total or smelling of banana) for each subject; (b) the intensity reported by each subject during the sniffing of the pen containing the banana aroma in the identification test is positively correlated both with its hedonic valence and the number of odor-active compounds smelling of banana. In conclusion, our findings show that human perception of single compounds is conditioned by the threshold olfactory performance of the subject and that his/her ability to detect single molecular components, which smell as the mixture, affects the intensity and hedonism for the complex aroma.

Assessing the hazard of E-Cigarette flavor mixtures using zebrafish

Since 2007, electronic cigarette (e-cigarette) sales in the U.S. have surpassed those of tobacco cigarettes. This is due, in part, to manufacturer's claims that they are a safer alternative to tobacco cigarettes. However, formaldehyde, acrolein, and diacetyl have been detected in e-cigarettes and public knowledge of e-cigarette composition and ingredient bioactivity is conspicuously lacking. We evaluated the toxicity of nine e-cigarette flavor mixtures and their constituents in the developmental zebrafish, an excellent whole animal biosensor of chemical hazard. Seven of the nine flavors (78%) elicited adverse developmental responses at 1% by volume. The number of toxic endpoints varied greatly between flavors. Two flavors, Grape and Bubble Gum, had similar chemical compositions, but different toxicity profiles. We hypothesized that the toxicity was driven by a constituent present only in the Bubble Gum flavor, cinnamaldehyde. To replicate this toxicity, we built our own defined mixture. The addition of varying concentrations of cinnamaldehyde suggested that it drove the toxicity of these mixtures and that e-cigarette hazard can be flavor dependent.