Aroma Molecules Research Articles

Kinetics of aroma formation from grape-derived precursors: Temperature effects and predictive potential

This study investigates the accumulation and degradation of aroma molecules released by acid hydrolysis of aroma precursors in winemaking grapes. A first-order kinetics model effectively interprets this accumulation, including subsequent degradation. Experimentation at three temperatures categorizes specific grape-derived aroma molecules into three stability-based groups: labile molecules from labile precursors, stable molecules from labile precursors, and stable molecules from stable precursors. While many grape-derived aromas exhibit similar patterns and levels of accumulation across temperatures, reaction rates significantly increase with temperature. The analysis of 12 samples of two grape varieties hydrolyzed at 50 °C for 5 weeks and 75 °C for 24 h confirms that fast hydrolysis accurately replicates varietal and between-sample aroma compositional differences. Moreover, the accumulated levels of 21 relevant grape-derived aromas strongly correlate with those at 50 °C, indicating that fast hydrolysis at 75 °C reliably predicts grape aroma potential.

Unlocking Nature's Aroma: Hora Perfumes and The Art of Harnessing Natural Fragrance Compounds

This study looks into the world of perfumery and how essential oils, plant extracts, and other organic materials can be changed to make fragrance molecules that can be used to make beautiful perfumes. It goes into great detail about the many aspects of the art and science of perfumery, with a focus on how important natural materials are for making unique and appealing scents. In addition, the paper looks at the complicated problems the perfume industry faces when it tries to balance the growing demand for natural scents with the moral obligation to use ingredients that are safe for customers and good for the environment. This study shows how difficult it can be to use natural fragrance compounds in perfumery by looking at a lot of previous research and successful case studies. It does this by shedding light on the topic and giving useful information for the perfume business and future research. After a comprehensive review of numerous research papers that delve into the complexities of perfume production, and following an in-depth analysis of customer surveys, we are excited to introduce our imaginative perfume brand.

Impact of cooking methods on the quality, sensory and flavor compounds of Sichuan pepper oleoresin.

Sichuan pepper oleoresin (SPO) is highly appreciated by the food industry as well as consumers for flavor. To understand the overall flavor of SPO and how the quality changes during practical application, this study investigated the effects of five cooking methods on the quality, sensory, and flavor compounds of SPO. The differences in physicochemical properties and sensory evaluation responded to potential changes in SPO after cooking. The SPO after different cooking could be clearly distinguished by E-nose and PCA. Based on the qualitative analysis of volatile compounds, 13 compounds were screened by OPLS-DA that had the ability to explain above differences. Further analysis of taste substances revealed that pungent substances (hydroxy-α-sanshool) were significantly reduced in SPO after cooking. And the conclusion that the degree of bitterness significantly increased was predicted by E-tongue. The PLS-R model was developed to achieve correlation analysis between aroma molecules and sensory quality.

Art of Aromatherapy: A Complementary Therapy in Healthcare Professional

Aromatherapy, a part of herbology, is one of today's rapid-developing treatments. Fundamental oils are best utilized asback rubs, shower oils, or inward breaths. It is often accounted for that fragrance-based treatment leaves one inclination elevated,animated, empowered, or restored, contingent upon the oil utilized. At the point when breathed in, the different smells infiltratethe circulatory system through the lungs, causing physiologic changes. Aromatherapy is a form of alternative medicine.Aromatherapy is becoming increasingly popular, and there are clear indications that it should be used. It is one of thecomplementary therapies for anxiety reduction. Derived aroma molecules from essential oils contain curative and preventive usesin the medicine department. Although the perception and reaction to essential oils appear to differ significantly between men andwomen, aromatherapy benefits people of all ages. This article mainly focuses on a narrative review of aromatherapy, Derivatives,and uses of essential oils with a widened horizon in Aromatology.

Scent and sustainability: investigating consumer evaluations of biocatalysis and naturalness in fragrances

With growing global environmental concerns, consumer acceptance of new technologies or innovation-derived products can be tied strongly with how natural the latter are perceived to be. A prior study found that fragrances were evaluated more positively if participants were informed that the fragrances were of natural origin. This led the authors to conclude that the perceived naturalness of a fragrance activates a positive effect, similar as for other consumer products. However, obtaining fragrant molecules from natural sources can pose a strain on the environment and biotechnology-based fragrances could potentially improve the sustainability of the perfumery industry. The primary goal of this study was to extent the findings of this initial study with a focus on biocatalysis-based fragrances. For this, a laboratory experiment was conducted with a 3x2x2 mixed design: participants smelled either three fragrances of natural origin or three biocatalysis-based fragrances and were either informed or not informed about the origin of the fragrances. In contrast to expectations, no consistent positive effect of natural origin or negative effect of biocatalysis-based origin of fragrances was found in our study. The results suggest that the participants were open to novel production methods in the fragrance industry. The discussion comprises a methodological comparison to the prior study, alternative explanations for these findings, and discusses insights for the fragrance industry and future research. Further research is needed to fully understand the complex factors that shape consumer behaviour in the fragrance industry.

Fragrance in dermocosmetic emulsions: From microstructure to skin application.

Fragrance is added to almost all dermocosmetic emulsions, as it has been found to be a key driver in consumer choice and contributes to the perception of product performance. Fragrance is a complex mixture of odorant chemicals at different concentrations. When incorporated into a formulation, the individual fragrance chemicals partition between the emulsion phases depending on their physicochemical properties, which can impact the structure, stability, texture and odour of the final product. On the other hand, it is well known in the food industry how the composition and structure of food emulsion matrices influence the release of aroma chemicals. Fragranced dermocosmetic emulsions have been studied to a lesser extent but it is interesting to apply findings from the food domain since emulsion structure, composition and aroma compounds share common features. This review aims to give an overview of the literature dealing with the interactions between fragrance and dermocosmetic emulsions. The effects of fragrance on emulsion microstructure, stability and texture are highlighted and discussed. The effects of composition and structure of emulsion on the release of fragrance molecules are also presented. Finally, the interactions between skin and fragranced emulsions are addressed.

Dynamic Instrumental and Sensory Methods Used to Link Aroma Release and Aroma Perception: A Review.

Perception of flavor is a dynamic process during which the concentration of aroma molecules at the olfactory epithelium varies with time as they are released progressively from the food in the mouth during consumption. The release kinetics depends on the food matrix itself but also on food oral processing, such as mastication behavior and food bolus formation with saliva, for which huge inter-individual variations exist due to physiological differences. Sensory methods such as time intensity (TI) or the more-recent methods temporal dominance of sensations (TDS) and temporal check-all-that-apply (TCATA) are used to account for the dynamic and time-related aspects of flavor perception. Direct injection mass spectrometry (DIMS) techniques that measure in real time aroma compounds directly in the nose (nosespace), aimed at obtaining data that reflect the pattern of aroma release in real time during food consumption and supposed to be representative of perception, have been developed over the last 25 years. Examples obtained with MS operated in chemical ionization mode at atmospheric or sub-atmospheric pressure (atmospheric pressure chemical ionization APCI or proton-transfer reaction PTR) are given, with emphases on studies conducted with simultaneous dynamic sensory evaluation. Inter-individual variations in terms of aroma release and their relevance for understanding flavor perception are discussed as well as the evidenced cross-modal interactions.

Comparing molecular representations, e-nose signals, and other featurization, for learning to smell aroma molecules.

Recent research has attempted to predict our perception of odorants using Machine Learning models. The featurization of the olfactory stimuli usually represents the odorants using molecular structure parameters, molecular fingerprints, mass spectra, or e-nose signals. However, the impact of the choice of featurization on predictive performance remains poorly reported in direct comparative studies. This paper experiments with different sensory features for several olfactory perception tasks. We investigate the multilabel classification of aroma molecules in odor descriptors. We investigate single-label classification not only in fine-grained odor descriptors ('orange', 'waxy', etc.), but also in odor descriptor groups. We created a database of odor vectors for 114 aroma molecules to conduct our experiments using a QCM (Quartz Crystal Microbalance) type smell sensor module (Aroma Coder®V2 Set). We compare these smell features with different baseline features to evaluate the cluster composition, considering the frequencies of the top odor descriptors carried by the aroma molecules. Experimental results suggest a statistically significant better performance of the QCM type smell sensor module compared with other baseline features with F1 evaluation metric.

New Lyotropic Complex Fluid Structured in Sheets of Ellipsoidal Micelles Solubilizing Fragrance Oils.

New lyotropic, fragranced, viscoelastic fluid with a complex structure is obtained from fragranced microemulsions by the addition of a fatty acid. Nonhomogeneous mixing of an appropriate nonionic surfactant, a fatty acid, and a fragrance oil led to the formation of anisotropically shaped and highly oriented micelles in aqueous solution. The nano- and microstructures, and consequently the viscosity, are controlled by the balance of fatty acids used as a cosurfactant and fragrance molecules, which partly behave as a cosurfactant and partly segregate in the micelles of the hydrophilic nonionic surfactant. The transition from isotropic microemulsion to a more structured viscoelastic solution is characterized by X-ray scattering and rheological methods. Considering our X-ray scattering results, we propose a structure composed of planar sheets of ellipsoidal micelles arranged in a lamellar type of stacking. The complex structured, low viscous, transparent fluid is capable of solubilizing a fragrance inside the ellipsoidal micelles, as well as retaining microparticles containing fragrance, without the addition of a polymeric thickener or another gelator. These features allow the creation of a 2-in-1 fragrance-solubilizing liquid product compatible with all types of home and body care consumer products.

Insempra launches biotech flavor molecule

Insempra is launching a fermentation- derived version of α-ionone, a flavor and fragrance molecule that smells like fresh violets and raspberries. The underlying technology was developed by Phytowelt Green Technologies. The α-ionone molecule can be produced synthetically or from natural sources, such as raspberries, almonds, and blackberries. Insempra says that customers are increasingly demanding natural ingredients but that sourcing α-ionone from crops is unsustainable.

Recovery of flavor compounds from vanilla bagasse by hydrolysis and their identification through UPLC-MSE

Vanilla is a globally treasured commodity, and the consequences of its unstable value affect social, environmental, economic, and academic ambits. The extensive range of aroma molecules found in cured vanilla beans is crucial to the complexity of this natural condiment and knowledge about their recovery is of the essence. Many strategies aim on reproducing the chemical intricacies of vanilla flavor, such as biotransformation and de novo biosynthesis. Few studies, however, aim at the exhaustion of the cured pods, of which the bagasse, after the traditional ethanolic extraction, might still bear a highly valued flavor composition. An untargeted liquid chromatography coupled with mass spectrometry (LC–MSE) approach was applied to elucidate if sequential alkaline–acidic hydrolysis was effective in extracting flavor related molecules and chemical classes from the hydro–ethanolic fraction. Important vanilla flavor related compounds present in the hydro-ethanolic fraction were further extracted from the residue through alkaline hydrolysis, such as vanillin, vanillic acid, 3-methoxybenzaldehyde, 4-vinylphenol, heptanoic acid, and protocatechuic acid. Acid hydrolysis was effective on further extracting features from classes such as phenols, prenol lipids, and organooxygen compounds, though representative molecules remain unknown. Finally, sequential alkaline–acidic hydrolysis rendered natural vanilla’s ethanolic extraction residues as an interesting supplier of its own products, which could be used as a food additive, and many other applications.

Comparative Study of Raw and Dehydrated Boletus edulis Mushrooms by Hot Air and Centrifugal Vacuum Processes: Functional Properties and Fatty Acid and Aroma Profiles

A study on Boletus edulis mushrooms subjected to either hot air drying (HAD) or centrifugal vacuum drying (CVD) was performed to evaluate and compare their functional properties, fatty acids, and aroma compounds. Better flowability and a higher rehydration ratio were observed for HAD powders, while enhanced indices of water solubility, emulsifying activity, and stability were noticed for CVD ones. The composition of 21 identified fatty acids varied between raw and dried samples, the most relevant being the decrease of oleic acid and the increase of linoleic acid during drying. The PUFAs/SFAs ratio was >3.3 in all samples, thus meeting the requirements for healthy lipids. Of the 15 aroma compounds identified in raw mushrooms, only hexanal, 1-octen-3-ol, and (Z)-2-octen-1-ol were also found in dried samples, to different extents; 1-octen-3-ol was the major volatile constituent in all samples. Low amounts of new alcohols, aldehydes and ketones, D-limonene, and caryophyllene were detected in HAD powders, while dimethyl disulfide and 2-n-pentyl-furan were detected in CVD ones. The drying of mushrooms resulted in a total loss of 2-methyl-2-butenal, (E)-2-octenal, and 1-octen-3-one. These findings become important milestones for food manufacturers and researchers in selecting the desired drying technique of B. edulis based on the powder/emulsifying properties and preservation of fatty acids and aroma molecules.

Flavour them up! Exploring the challenges of flavoured plant‐based foods

AbstractFood flavourings are often added to enhance overall flavour experience during food consumption and their use in plant‐based food analogues is crucial. The flavour sensory perception is strongly mediated by flavour–food matrix interactions. Aroma molecules establish chemical and physical bonds with lipids and carbohydrates, but proteins play a pivotal role having a strong flavour binding minimizing aroma release and quenching flavour perception. Consequently, final food quality is reduced and so is consumer acceptance. Depending on the chemical structure of the flavour and the type of protein involved, the strength of the flavour–protein binding can vary. It is of great importance to understand if this interaction remains under dynamic conditions such as the oral processing during food consumption. This review aims to gain insights into the influence of the chemical structure and physicochemical features of both proteins and flavours on the binding mechanism. Moreover, the potentiality of coupling in vivo instrumental analysis with sensory methods to study flavour release in real time is explored. Elucidating the drivers of flavour interaction with, and release from, the food matrix is essential to develop flavour solutions for the new generation of plant‐based food products.

Do Synthetic Fragrances in Personal Care and Household Products Impact Indoor Air Quality and Pose Health Risks?

Fragrance compounds (synthetic fragrances or natural essential oils) comprise formulations of specific combinations of individual materials or mixtures. Natural or synthetic scents are core constituents of personal care and household products (PCHPs) that impart attractiveness to the olfactory perception and disguise the unpleasant odor of the formula components of PCHPs. Fragrance chemicals have beneficial properties that allow their use in aromatherapy. However, because fragrances and formula constituents of PCHPs are volatile organic compounds (VOCs), vulnerable populations are exposed daily to variable indoor concentrations of these chemicals. Fragrance molecules may trigger various acute and chronic pathological conditions because of repetitive human exposure to indoor environments at home and workplaces. The negative impact of fragrance chemicals on human health includes cutaneous, respiratory, and systemic effects (e.g., headaches, asthma attacks, breathing difficulties, cardiovascular and neurological problems) and distress in workplaces. Pathologies related to synthetic perfumes are associated with allergic reactions (e.g., cutaneous and pulmonary hypersensitivity) and potentially with the perturbation of the endocrine-immune-neural axis. The present review aims to critically call attention to odorant VOCs, particularly synthetic fragrances and associated formula components of PCHPs, potentially impacting indoor air quality and negatively affecting human health.

Copper(I)-Iodide Clusters as Carriers for Regulating and Visualizing Release of Aroma Molecules.

Achieving the controlled release of functional substances is indispensable in many aspects of life. Especially for the aroma molecules, their effective delivery of flavor and fragrance is challenging. Here, selected pyridines, as highly volatile odorants, were individually coordinated with copper(I) iodide (CuII) via a straightforward one-pot synthesis method, rapidly forming pure or even crystalline CuII cluster-based profragrances at room temperature. The obtained profragrances enabled the stable and high loading of volatile fragrances under ambient conditions and guaranteed their long-lasting release during heating. Furthermore, the intrinsic emission luminescence of these solid-state profragrances decayed along with the aroma release, which can serve as an additional indicator for monitoring the delivery process. This research sets a precedent for using CuII clusters as dual-purpose release agents and greatly expands their potential applications.

A new fan-like adaptive porous organic cage for the structure determination of liquid perfume molecules

Chloroform and nine liquid perfume guests were successfully encapsulated by a newly synthesized fan-like adaptive porous organic cage.

Encapsulation of Volatile Monoterpene Fragrances in Mesoporous Organosilica Nanoparticles and Potential Application in Fruit Preservation.

In this work, we synthesized mesoporous silica nanoparticles (MSNs) and periodic mesoporous organosilica nanoparticles containing bridging groups of ethylene (E-PMO) and phenylene (P-PMO) and compared their adsorption properties using D-limonene (Lim), myrcene (Myr), and cymene (Cym) as model guest molecules. For the selected nanoparticles of ~100 nm in diameter, the loading capacity to the volatile fragrances was in the order of P-PMO < E-PMO < MSN, consistent with the trend of increasing total pore volume. For example, P-PMO, E-PMO, and MSN had a Lim uptake of 42.2 wt%, 47.3 wt%, and 62.7 wt%, respectively, which was close to their theoretical adsorption capacity. Under isothermal thermogravimetric analysis conditions (30 °C, a N2 flow of 1 mL min−1), the lowest fragrance release of ~56% over 24 h was observed for P-PMO, followed by E-PMO (74−80%), and MSN (~89%). The release kinetics of the fragrant molecules from MSN and PMO materials can be well described by first-order and Weibull models, respectively. Moreover, the incorporation of Lim-loaded P-PMO NPs in an aqueous solution of regenerated silk fibroin provided a composite coating material suitable for perishable fruit preservation. The active layer deposited on fruit peels using dip coating showed good preservation efficacy, enabling the shelf-life of mangoes in a highly humid and hot atmosphere (30−35 °C, 75−85% RH) to be extended to 6 days.

Engineering volatile thiol formation in yeast.

Volatile thiols are very potent aroma molecules which contribute to the aroma of many beverages. The characteristic thiols of certain wine varieties like Sauvignon Blanc are partly released during the yeast-based fermentation from plant-synthesized glutathione- or cysteine-conjugated and dipeptic precursors present in the must. In this work, we aimed at the construction and characterization of yeast strains with the ability to synthesize volatile thiols from respective precursors. Besides genome integration of the Escherichia coli gene tnaA, which encodes an enzyme with high β-lyase activity, a glutathione synthetase and glutathione-S-transferases were overexpressed. Up to 8.9µg L-1 3-mercaptohexan-1-ol could be formed with the strain from externally added trans-2-hexen-1-ol. Well characterized thiols such as 2-methyl-2-butanethiol, 3-mercapto-3-methylbutan-1-ol and 8-mercapto-p-menthan-3-one, as well as several so far undescribed thiol compounds could be synthesized. Volatile thiols could be produced by feedingalcohol, alkenol, aldehyde or ketone precursors like trans-2-hexenal, trans-2-hexen-1-ol, cis-2-hexen-1-ol, 3-methyl-2-buten-1-ol, 3-buten-2-one and pulegone to the optimized yeast cells.

A breathing A4 paper by in situ growth of green metal–organic frameworks for air freshening and cleaning

Here, we prepared γ-CD-MOF@A4 nanocomposites through in-situ growth of γ-CD-MOFs on A4 printing paper for indoor air fresh and cleaning, including air pollutant capture, antibacterial, and fragrance encapsulation and release. Surface modification of natural cellulose fibers with nanomaterials is an effective strategy for producing functional textiles for multiple applications. A4-sized printing paper is a commonly used, cheap, and easily acquirable office supply which is mainly made of cellulose fibers. Here, we report green and simple nanofabrication of A4 paper to endow it with high capability for fragrance encapsulation and sustained release, and strong adsorption to indoor air pollutants. The method utilizes the sugar molecule of cellulose for in-situ growth of γ -cyclodextrin ( γ -CD) metal–organic frameworks (MOFs) on A4 paper. The obtained γ -CD-MOF/A4 nanocomposites have superior specific surface area and high porous structure. γ -CD-MOF/A4 nanocomposites can effectively encapsulate fragrant molecules through host-guest interaction. γ -CD-MOF/A4 nanocomposites also show strong absorption capability to formaldehyde and carbon dioxide through the formation of hydrogen bonding and chemical bond. The γ -CD-MOF/A4 nanocomposites combine the advantages of both A4 paper and γ -CD-MOF, which can be used in indoor air freshening and cleaning.

Structure- and computational-aided engineering of an oxidase to produce isoeugenol from a lignin-derived compound

Various 4-alkylphenols can be easily obtained through reductive catalytic fractionation of lignocellulosic biomass. Selective dehydrogenation of 4-n-propylguaiacol results in the formation of isoeugenol, a valuable flavor and fragrance molecule and versatile precursor compound. Here we present the engineering of a bacterial eugenol oxidase to catalyze this reaction. Five mutations, identified from computational predictions, are first introduced to render the enzyme more thermostable. Other mutations are then added and analyzed to enhance chemoselectivity and activity. Structural insight demonstrates that the slow catalytic activity of an otherwise promising enzyme variant is due the formation of a slowly-decaying covalent substrate-flavin cofactor adduct that can be remedied by targeted residue changes. The final engineered variant comprises eight mutations, is thermostable, displays good activity and acts as a highly chemoselective 4-n-propylguaiacol oxidase. We lastly use our engineered biocatalyst in an illustrative preparative reaction at gram-scale. Our findings show that a natural enzyme can be redesigned into a tailored biocatalyst capable of valorizing lignin-based monophenols.