Release Of Aroma Compounds Research Articles

Unraveling the role of peanut protein in baijiu-peanut pairing flavor complexity: A focus on ethanol-induced denaturation

Food processing, cooking, and consumption introduce various factors that affect food flavor, distinguishing it from its objective composition. This study focuses on liquor-accompanying food pairing, investigating the interaction between baijiu aroma compounds and peanut proteins, and the effect of ethanol on it. Peanut globulins significantly inhibited the release of baijiu aroma compounds through hydrogen bonding (2.63–3.23 Å), hydrophobic interactions, and covalent reactions (−2.85 to −5.64 kcal/mol), resulting in flavor modification. In the presence of ethanol, peanut globulins adopt a more compact and aggregated structure, reducing their affinity for binding aroma compounds. Surprisingly, this structural change promotes a salting-out effect, significantly promoting the release of aldehydes, phenols, and aromatic compounds, enhancing the grassy, floral, and sweet aroma of baijiu. This finding improves the understanding of alcohol pairing and proposes a novel strategy for enhancing the overall flavor profile of baijiu by modifying accompanying food choices.

Influence of Cheese Composition on Aroma Content, Release, and Perception.

The quality of a cheese is determined by the balance of aroma compounds primarily produced by microorganisms during the transformation of milk into ripened cheese. The microorganisms, along with the technological parameters used in cheese production, influence aroma formation. The perception of these compounds is further influenced by the composition and structure of the cheese. This study aimed to characterize how cheese composition affects aroma compound production, release, and perception. Sixteen cheeses were produced under controlled conditions, followed by a quantitative descriptive analysis post ripening. Aroma composition was analyzed using HS-SPME-GC-MS, and a dynamic sensory evaluation (TCATA) was combined with nosespace analysis using PTR-ToF-MS. Image analysis was also conducted to characterize cheese structure. Cheese fat and whey lactose contents were identified as key factors in the variability of sensory attributes. GC-MS analyses identified 27 compounds correlated with sensory attributes. In terms of aroma compound release, 23 ions were monitored, with fat, salt, and lactose levels significantly affecting the release of most compounds. Therefore, cheese fat, salt, and whey lactose levels, as well as the types of microbial strains, play a role in influencing the composition, structure, release of aroma compounds, and sensory perception.

Improvement of rheological and sensory properties of Lactobacillus helveticus fermented milk by prebiotics

The fermentation characteristics and aroma-producing properties of Lactobacilli could influence the flavour quality of fermented milk, an important influencing factor of consumers' preference. In this study, fermented milk was prepared using Lactobacillus helveticus and the dynamic changes in the sensory quality of fermented milk throught fermentation were to assess the dynamic changes in sensory quality of fermented milks throughout the fermentation process, including rheological properties and flavour profiles. Styrene, linalool, octanoic acid, and 1-nonanol were considered as the key flavour components during fermentation. The quality of the fermented milk tends to be stabilized after 24-h, showing the minimal off-flavour at 48-h and optimal fermented aroma at 72-h. Three prebiotics (inulin, Galactooligosaccharides and inulin mixed with Galactooligosaccharides) were added to Lactobacillus spiralis fermented milk separately, and the results showed that inulin mixed with Galactooligosaccharides was the most effective group in improving the organoleptic quality of the fermented milk. Overall, the experimental results provide deeper insights into the release and retention of aroma compounds during fermentation and scientific reference for broadening the application of prebiotics and flavour-producing Lactobacilli in fermented milk processing.

Effects of ethyl palmitate on the release of aroma compounds in propanediol-ethanol solution and its mechanisms.

Long-chain esters (LCEs) are known to affect aroma perception, but the mechanism of their effects remains unclear. In this study, ethyl palmitate (EP), an important LCE in Osmanthus fragrans flower absolute (OFFA), was selected as a target to identify its role and mechanism. The release characteristics of 10 aroma compounds from OFFA with and without EP were obtained by headspace gas chromatography mass spectrometry (HS-GC/MS) and olfactometry evaluation, respectively. The results show that EP changes the release behaviors of volatile compounds in solution, increases their olfactory detection thresholds (ODTs), and reduces the equilibrium headspace concentrations. According to Whitman's two-film model, EP was found to change the partition coefficients and mass transfer coefficients of the compounds between the liquid and gas phases. This indicates that EP plays an important role in the scent formation of a flavor product and that it is very valuable for the style design of the flavor product.

Effects of polyols at low concentration on the release of sweet aroma compounds in model soda beverages

This study investigated the effect of polyols erythritol, d-mannitol, and maltitol on the volatility of aroma compounds γ-butyrolactone, 3-methyl-1-butanol, and 2-phenylethanol in aqueous solution. Headspace solid-phase microextraction/gas chromatography and diffusion-ordered nuclear magnetic resonance techniques were used to obtain information on aroma–food matrix interaction. Results demonstrated that adding polyols at final low concentrations of 5% or 10% (w/w) to an aqueous solution of 2-phenylethanol reduced the release of vapor-phase aromas, except in the case of 3-methyl-1-butanol, which was not affected by the presence of polyols in the liquid matrix. Polyols also reduced the diffusion coefficients of all three aroma compounds, probably due to friction between the molecules. At low polyol concentrations, aroma compound volatility and diffusion coefficient values were altered compared to those of aromas released from pure water. This observation is related to the physicochemical properties of the aroma compounds. These insights may help guide the use of the combination of aroma compounds and polyols in the formulation of sugar-free and reduced-sugar beverages. Chemical compoundsγ-butyrolactone (PubChem CID: 7302), 3-methyl-1-butanol (PubChem CID: 31260), 2-phenylethanol (PubChem CID: 6054), erythritol (PubChem CID: 222285), d-mannitol (PubChem CID: 6251), maltitol (PubChem CID: 493591).

Kinetic analysis of aroma compound release from Citrus aurantium essential oil-casein-phospholipid-nanocomposites

In this study, Citrus aurantium essential oil encapsulated in casein-phospholipid nanocomposites (CAEO–CS–PL-NCs) was prepared and evaluated for controlled-release capacity of aroma compounds. The particle size of the nanocomposites was strongly influenced by the phospholipid concentration in the nanocomposites. The Avrami and Korsmeyer-Peppas kinetic models were used to analyze the aroma release kinetics of freeze-dried CAEO–CS–PL-NCs (FD-CAEO–CS–PL-NCs) at different temperatures and relative humidities. FD-CAEO–CS–PL-NCs were stored for various times with tea leaves to evaluate their potential for making scented teas. The Avrami kinetic analysis indicated that the release of aroma compounds from FD-CAEO–CS–PL-NCs conformed to diffusion-limited, or first-order kinetics, depending on the temperature and relative humidity. The Korsmeyer-Peppas kinetic analysis indicated that the release of aroma compounds from FD-CAEO–CS–PL-NCs involved three release mechanisms, Fickian diffusion, non-Fickian diffusion and the erosive mechanism. The release mechanism involved varied depending on different conditions and different aroma compounds, and at low temperature and relative humidity effective controlled release of aroma compounds was achieved, resulting from intermolecular interactions with the casein micelles. FD-CAEO–CS–PL-NCs showed significantly sensory scores increasing effect of scented tea. The findings will facilitate future developments in the formulation of scented teas, by incorporating aromatic essential oils from fruits and flowers, in the form of essential oil-casein-phospholipid nanocomposites.

Headspace volatiles profiles of different spring varieties and a wild relative of wheat flour.

Volatile profiling was conducted on four wheat varieties Triticum aestivum cv. Chinese Spring (CS), Highbury (High), Paragon (Para), Pavon76 (Pav76), and one wild relative Triticum timopheevii (P95). Headspace solid-phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to explore differences in flavor formation mechanisms in different flours before and after starch gelatinization. Solvent retention capacity (SRC) analysis revealed subtle differences in water absorption, gluten strength, and starch characteristics across wheat flour types. Rapid Visco Analysis (RVA) of whole wheat flour demonstrated significant variations in pasting properties among wheat varieties, with P95 exhibiting higher viscosities compared to CS and High potentially influenced by starch gelatinization, protein-starch interactions, and lipid content. Aroma contributions of P95 clustered positively in PCA plots, contrasting with the four main varieties, indicative of species-level differentiation. Furthermore, the study highlighted the roles of viscosity, protein structure, lipid content, and fatty acid composition in modulating the release and perception of volatile aroma compounds during heating. This study sheds light on how the distinct characteristics of wheat flour influence aroma profiles, revealing species-level differences and the pivotal role of physiochemical properties in shaping flavor development mechanisms.

Aroma compounds retention and release from protein-polysaccharide-based bilayer emulsion gels: A thermodynamic and kinetic study

Thermodynamic and kinetic behavior of five aroma compounds (ACs) with different molecular structures in bilayer-stabilized emulsion gels (BEGs) depending on starch type (ST) and starch concentration (SC) during refrigerated storage time (RST) was investigated. The internal phase of BEGs was stabilized by myofibrillar proteins (MPs) and gum arabic, while the external phase was thickened and texturized with MPs and starches (waxy maize starch, potato starch) differing in amylose/amylopectin ratio. Oscillatory and rotational shear modes were used to evaluate rheological properties of BEGs, and the results are presented in terms of: Herschel-Bulkley parameters, quality factor and divergence from the Cox-Merz rule, which were modeled using a first order kinetic equation. Thermodynamic models composed of myosin and ACs were applied to determine the Stern-Volmer quenching constants, binding and thermodynamic parameters: enthalpy (ΔH), entropy (ΔS) and Gibb’s free energy (ΔG). Retention (R), release rate constant (kr) and mechanism of release (nr) values were significantly (p ≤ 0.05) dependent on: ST, SC and ACs type. After 12 days of refrigerated storage, the R values were ranged from 0.34 to 0.77, whereas those of kr and nr determined during RST were in ranges 6.21–102 × 10−3 (day−1) and 0.55–0.86, respectively. The gas-BEGs partition coefficient (kg/e) of ACs was measured at thermodynamic equilibrium and the enthalpy of vaporization was calculated from the variations of kg/e with temperature changes (30–60 °C). From a practical point of view, these results may have important implications for the development of commercial emulsion-type food with controlled ACs retention during RST.

Effects of gallic acid on the release of aroma compounds in Moutai Baijiu

Due to the trace concentrations of gallic acid (GA), the interaction mechanism between GA and flavor compounds is limited, and the effects on the aroma compounds of Moutai Baijiu are even more unclear. In this study, the aroma compounds and phenolic compounds in Moutai Baijiu were investigated by stir bar sorptive extraction (SBSE), gas chromatography–olfactometry (GC-O), gas chromatography-mass spectrometry (GC–MS) and liquid chromatography-mass spectrometry (LC-MS). A total of 63 volatiles and 10 phenolic compounds were identified, and 16 esters and 4 alcohols were identified as the important aroma substances (odor activity values ≥1). The effect of GA on the release of aroma compounds was investigated by sensory analysis and partition coefficient. The results showed that GA mainly inhibited the volatilization of alcohols, low concentrations of GA promoted the release of esters, and high concentrations slowed down or even inhibited the release effect affected by the hydrophobicity of aroma compounds. UV spectroscopy and thermodynamic analysis further revealed that the interaction of GA with 1-propanol was attributed mainly to hydrogen bonding and van der Waals forces, and the interaction with other compounds was mainly influenced by hydrophobic effects. These results show that gallic acid can effectively control the release of the aromas of Moutai Baijiu, highlight the important role of GA on the volatiles of baijiu, and provide theoretical support for further healthy improvement of the sensory quality of baijiu.

Impact of Fat Replacers on the Rheological, Tribological, and Aroma Release Properties of Reduced‐Fat Model Emulsion Systems and Processed Cheese

Impact of Fat Replacers on the Rheological, Tribological, and Aroma Release Properties of Reduced‐Fat Model Emulsion Systems and Processed Cheese

Aroma formation and transformation during sealed yellowing process of Pingyang yellow tea

Yellow tea, a unique type of tea in China which is characterized with yellow color, has gained increasing popularity due to its pleasant taste. However, transformation of aroma compounds during sealed yellowing has been poorly understood. Results of sensory evaluation exhibited that yellowing time was the key factor for flavor and fragrance formation. A total of 52 volatile components during sealed yellowing process of Pingyang yellow soup were further collected and analyzed. The results demonstrated that the sealed yellowing process significantly increased the ratio of alcohol and aldehyde compounds in the aroma volatiles of yellow tea, which were primarily composed of geraniol, linalool, phenylacetaldehyde, linalool oxide and cis-3-hexenol, and their proportion increased with the prolongation of sealed yellowing. Mechanistic speculation revealed that the sealed yellowing process promoted release of alcoholic aroma compounds from their glycoside precursors and enhanced Strecker and oxidative degradation. This study revealed the transformation mechanism of aroma profile during the sealed yellowing process, which would facilitate processing of yellow tea.

Characterization of aroma compounds and effects of amino acids on the release of esters in Laimao baijiu.

Laimao baijiu is a typical soy-sauce aroma-type baijiu in China. Amino acids are non-volatile compounds in baijiu and are beneficial to human health. Aroma is one of the important indicators that are used to evaluate the quality of baijiu. The interaction between aroma-active compounds and non-volatile compounds can also affect the release of aroma compounds. In this study, we identified the active-aroma compounds and amino acids in Laimao baijiu by stir bar sorptive extraction (SBSE), gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The interaction between amino acids and key esters was investigated by sensory analysis and partition coefficients. A total of 63 aroma compounds and 21 amino acids were identified. Twenty-one esters were identified from them as major aroma-active ester compounds with odor activity values ≥ 1. Finally, sensory analysis revealed that l-alanine had a significant effect on the strength of the aromas of esters, suggesting that low concentrations of amino acids were more likely to promote the release of esters and high concentrations were more likely to inhibit this. The partition coefficient can be a good explanation for this phenomenon. l-Alanine can significantly affect the aroma intensity of key ester aroma compounds in Laimao baijiu, and the effects of different concentrations of amino acids are different. This work shows that amino acids, as non-volatile compounds, have a regulatory effect on the release of aroma compounds in alcoholic beverages, which may provide new technical support for the aroma modulation of alcoholic beverages. © 2022 Society of Chemical Industry.

Investigation of non-Saccharomyces yeasts with intracellular β-glycosidase activity for wine aroma modification.

Since high proportions of aroma-relevant molecules in plant-derived juices are present in glycosylated forms, the introduction of glycosidase activity during processing is an important tool to modify the aroma composition of the product. During winemaking, the addition of β-glycosidase enzyme or microorganisms with β-glycosidase activity is an established technology. However, low stability under acidic conditions and low selectivity for hydrolysis of different glycosides are still drawbacks, which limit application possibilities. Here, we report the identification and characterization of non-Saccharomyces yeast strains with relatively high β-glycosidase activity in their cultures. We found strong indications for intracellular localization of the enzymes, which is in line with the pH robustness found in experiments with whole cells. Furthermore, we compared the selectivity of aroma compound release from glycoside mixtures using whole cells or cell extracts. The results showed strong differences for the released aroma patterns, which indicates the transport of glycosides and intracellular hydrolysis. Our work demonstrates the application potential of yeasts with intracellular β-glycosidase activities as catalysts with high pH robustness and selective aroma release properties. PRACTICAL APPLICATION: The yeast strains identified and characterized within this work can be applied in wine processing but also in other processes to release aroma molecules from their glycosylated precursors provided by the plants. The strains show relatively high activity of the relevant enzyme, β-glycosidase, also at low pH, which is essential in many processes. In contrast to most other approaches, the enzyme is inside the cells, which can lead to a specific release of certain aroma compounds.

Characterisation of Refined Marc Distillates with Alternative Oak Products Using Different Analytical Approaches

The use of oak barrel alternatives, including oak chips, oak staves and oak powder, is quite common in the production of spirits obtained from the distillation of vegetal fermented products such as grape pomace. This work explored the use of unconventional wood formats such as peeled and sliced wood. The use of poplar wood was also evaluated to verify its technological uses to produce aged spirits. To this aim, GC-MS analyses were carried out to obtain an aromatic characterisation of experimental distillates treated with these products. Moreover, the same spirits were studied for classification purposes using NMR, NIR and e-nose. A significant change in the original composition of grape pomace distillate due to sorption phenomena was observed; the intensity of this effect was greater for poplar wood. The release of aroma compounds from wood depended both on the toasting level and wood assortment. Higher levels of xylovolatiles, namely, whisky lactone, were measured in samples aged using sliced woods. Both the NIR and NMR analyses highlighted similarities among samples refined with oak tablets, differentiating them from the other wood types. Finally, E-nose seemed to be a promising alternative to spectroscopic methods both for the simplicity of sample preparation and method portability.

Elucidation of the interaction between fructose and key aroma compounds in watermelon juice via Raman spectroscopy and nuclear magnetic resonance

Food matrix composition is an important factor affecting the release of aroma compounds. In the present study, four key aroma compounds (namely, hexanal, nonanal, (E)-2-nonenal, and acetophenone) were quantified in watermelon juice by stable isotope dilution assay. Using Raman spectroscopy and 1H NMR, it was found that hexanal, nonanal, and (E)-2-nonenal combine with fructose via hydrogen bonds, whereas acetophenone interact with fructose via π-π interaction. Entropy compensation at higher temperatures may explain the decrease in the contents of hexanal, nonanal, and (E)-2-nonenal released from the system. In contrast, the decrease in the contents of these aroma compounds by H2O2 might be due to the formation of a greater number of hydrogen bonds with carboxyl groups oxidized by aldehydes. This study contributes to further the understanding on the interaction between aroma compounds and fructose, thus offering practical insights on the regulation and control of flavor development in watermelon juice.

Human Breast Milk: A Source of Potential Probiotic Candidates.

This study focuses on the isolation of lactobacilli/bifidobacteria from human breast milk and their first characterization, in the perspective to find new probiotic candidates to be included in food products. More specifically, breast-milk-isolated strains demonstrated a very good aptitude to adhere to intestinal cells, in comparison with L. rhamnosus GG strain, taken as reference. The same behavior has been found for hydrophobicity/auto-aggregation properties. A remarkable antagonistic activity was detected for these isolates not only against spoilage and pathogenic species of food interest, but also against the principal etiological agents of intestinal infections. Indeed, isolated strains impaired spoilage and pathogenic species growth, as well as biofilm formation by gut pathogens. In addition, breast milk strains were characterized for their antibiotic susceptibility, displaying species-specific and strain-specific susceptibility patterns. Finally, to assess their technological potential, the fermentation kinetics and viability of breast milk strains in pasteurized milk were investigated, also including the study of the volatile molecule profiles. In this regard, all the strains pointed out the release of aroma compounds frequently associated with the sensory quality of several dairy products such as acetic acid, diacetyl, acetoin, acetaldehyde. Data here reported point up the high potential of breast-milk-isolated strains as probiotics.

Retronasal Aroma of Beef Pate Analyzed by a Chewing Simulator

In retronasal aroma, the targeted aroma compounds are released from food during chewing. The changes in the food structures during chewing strongly influence the release of the compounds, therefore affecting the perception of food. Here, the relationship between retronasal aroma and food deliciousness based on the physicochemical properties of aroma compounds was examined. We considered the consumption of solid foods and the effect of oral parameters in elderly people. Beef pate was used as a model food sample to study the effect of the release of aroma compounds under controlled in vitro mastication and salivation conditions using a chewing simulator. We identified the effects of coexisting ingredients such as beef fat on the time course behavior of the release of aroma compounds. In particular, the release of the middle types of aromas was significantly faster with stronger chewing force, and higher with a high fat content of the sample. In addition, a larger release intensity was observed when soy proteins were partially substituted for beef proteins. Using an appropriate model saliva, a change in the salting-out effect from the saliva composition was found to be a factor, which could explain the lowering of aroma sensation in an elderly person.

Modulating aroma release of flavour oil emulsion based on mucoadhesive property of tannic acid

Flavour is a crucial sensory element that determines the consumers’ preference for food and beverages. In this study, we determined the effects of complex gum arabic (GA) and tannic acid (TA) on the aroma release of flavour oil emulsions in vitro by simulating oral processing conditions. GA and TA were used to stabilize flavour oil emulsions. Visualization of in vitro retention using ex vivo porcine tongue, detection of aroma release in the model mouth, and sensory evaluation of flavour emulsions were performed to determine the effect of TA and GA. The results indicated that the retention of emulsions and the release of aroma compounds were modulated by TA and GA, which could be because of interactions that occurred between GA and TA in emulsions and mucins on the tongue. GA enhanced aroma release, whereas TA contributed to the retention or slow release of target aroma compounds.

Effects of composition and storage time of biopolymers-based emulsion-filled gels on the retention and release of aroma compounds: Thermodynamic and kinetic studies

Studies were performed to determine retention (R) and release kinetics (kr) of aroma compounds (ACs): ethyl butyrate, linalool, 1-octen-3-ol, 2-heptanone and octanal from emulsion-filled gels (EFGs), stabilized by myofibrillar proteins and waxy rice starch (WRS) or tapioca starch (TS). The R and kr parameters were affected by non-covalent interactions of ACs with biopolymers and the development of a compact structure induced by starch addition. Higher kr magnitudes were found in WRS-based samples (88.2–12.8 × 10–3 day−1) than in counterparts prepared with TS (87.6–8.96 × 10–3 day−1). Thermodynamic tests revealed that vaporization enthalpies of ACs were in ranges: 22.6–41.2 kJ mol−1 or 21.4–39.8 kJ mol−1 in samples containing WRS or TS, respectively. This study provides new insight into the factors affecting ACs stability in the EFGs, and the results reported can be used by industry to design relevant systems with extended volatiles retention.

Elucidation of retro‐ and orthonasal aroma differences in biscuits ( panis biscoctus ) using artificial masticator

The present study aimed to define the interest in using a mastication simulator to understand the release of aroma compounds of biscuits in the mouth. The development of aroma compounds during artificial, human mastication and without masticated samples of veritable biscuits was determined. Then, the evaluations of aroma compounds in different types of biscuits were studied. A total of 32 compounds were identified in the veritable sample while 36 were identified in both sugar-free and organic samples. The aldehydes and pyrazines were the main chemical groups in the samples. The number of aroma compounds in the biscuit samples revealed essential changes during mastication and increased about 2.5 times. Additionally, the presence of artificial and human saliva showed a similar effect. They increased the number of volatiles while influencing some volatile groups either by increasing the quantity of ketones or decreasing acids, alcohols, and aldehydes. Novelty impact statement The aroma of biscuits overwhelmingly effects consumer behavior. Hence, the improvements ingredients and manipulation in biscuits have become increasingly important. The artificial mouth would be particularly useful to study whether there is a difference between orthonasal and retronasal perception of dry and starch-rich foods.