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The objective of this study was to investigate the impact of co-fermentation of Italia and Negra Criolla grape musts using non-Saccharomyces yeast strains (NSYSs) isolated from both grape varieties, on the major volatile compounds and sensory characteristics of Piscos (distilled spirits). Native NSYSs previously isolated from Italia (Pichia terricola, Metschnikowia pulcherrima, and Naganishia vaughanmartiniae) and Negra Criolla (Vishniacozyma carnescens, Vishniacozyma heimaeyensis, and Aureobasidium pullulans) grapes' skins were inoculated at the beginning of grape must fermentation. A centroid simplex design was applied in order to obtain 10 representative yeast blends for use as mono- (n = 3), bi- (n = 3), and ternary (n = 4) inoculations. Additionally, a control sample without inoculum was also set up. For each yeast blend, the volatile composition and sensory characteristics of Piscos were evaluated. Results showed that mono-inoculation using specific NSYSs, such as P. terricola, M. pulcherrima, and N. vaughanmartiniae, led to a notable predominance of some terpenes such as α-terpineol, citronerol, and geraniol in Pisco from Italia grapes compared to the control Pisco. Conversely, in Pisco from Negra Criolla grapes, where V. carnescens, V. heimaeyensis, and A. pullulans were used in a similar mono-inoculation process, a higher presence of phenylethyl alcohol and 2-phenylethyl acetate compared to the control was observed. The sensory analysis revealed that citrus, floral, alcohol, and syrup descriptors had a higher intensity in mono-inoculated Pisco Italia, whereas spice, herbaceous, and cooked vegetable descriptors had the highest intensity in Negra Criolla Piscos produced with ternary NSYS inoculum inoculations. This study demonstrates that the use of native non-Saccharomyces yeast strains in the co-fermentation of grape musts can significantly influence the volatile profile and sensory characteristics of Pisco. These findings will allow us to establish new inoculation strategies to impact the overall sensory and aromatic profile of the Piscos produced with different grape varieties. [ABSTRACT FROM AUTHOR]

Aroma plays a pivotal role in defining tea quality and distinctiveness, and tea producers have often observed that specific drought conditions are closely associated with the formation and accumulation of characteristic aroma compounds in tea leaves. However, there is still limited understanding of the differential strategies employed by various tea cultivars in response to drought stress for the accumulation of key volatile aroma compounds in fresh tea leaves, as well as the associated metabolic pathways involved in aroma formation. In this study, two widely cultivated tea cultivars in China, Fuding Dabai (FD) and Wuniuzao (WNZ), were examined to assess the impact of mild field drought stress on the composition and accumulation of key volatile aroma compounds in fresh leaves using headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS) and headspace solid phase micro-extraction gas chromatography–mass spectrometry (HS-SPME-GC-MS) technologies. Results revealed that drought stress led to a substantial increase in the diversity of volatile compounds (VOCs) in FD, while WNZ exhibited a notable rise in low-threshold VOC concentrations, amplifying sweet, floral, fruity, and earthy aroma profiles in post-drought fresh leaves. Through partial least squares discriminant analysis (PLS-DA) of HS-GC-IMS and HS-SPME-GC-MS data, integrating variable importance projection (VIP) scores and odor activity values (OAVs) above 1, 9, and 13, key odor-active compounds were identified as potential markers distinguishing the drought responses in the two cultivars. These compounds serve as crucial indicators of the aromatic profile shifts induced by drought, providing insights into the differential metabolic strategies of the cultivars. Additionally, KEGG enrichment analysis revealed 12 metabolic pathways, such as terpenoid biosynthesis, fatty acid synthesis, cutin, suberine, and wax biosynthesis, and phenylalanine metabolism, which may play crucial roles in the formation and accumulation of VOCs in tea leaves under drought stress. These findings provide a comprehensive framework for understanding the cultivar-specific mechanisms of aroma formation and accumulation in tea leaves under mild drought conditions. [ABSTRACT FROM AUTHOR]

Abstract The objective of this work was to compare salep orchid species based on the composition of the volatile compounds of their tubers. Tuber samples extracted by solid-phase microextraction were analyzed by gas chromatography-mass spectrometry. In all studied species, p-cresol was the main volatile compound detected. The highest p-cresol proportion was found in Anacamptis laxiflora (76.31%), followed by Ophrys sphegodes subsp. mammosa (62.72%), Orchis coriophora (55.95%), and Anacamptis pyramidalis (21.19%). The proportions of the other volatile compounds also varied significantly between the evaluated species. The clustering analysis of the species according to their volatile compounds showed that A. laxiflora and O. coriophora were the closest, while A. laxiflora and A. pyramidalis were the most distant.

Aqueous extracts from four different American hops varieties (Mosaic, Chinook, Citra, and Centennial) were produced using the Synergy Pure technique, an innovative extraction distillation process developed by Synergy Flavours, a global specialist in the manufacturing of flavors, extracts and essences. This process is able to preserve and maximize the aromatic characteristics without increasing the bitterness of the final product. Therefore, the aim of this work is to identify the volatile and sensory characteristics of these extracts, with the additional aim to assess their suitability for brewing. GC-MS and sensory analyses were carried out on the four different aqueous extracts. The results highlighted the presence of 33 volatile compounds in a quantity that allowed us to identify the characteristics of the varieties under investigation in each extract. Sensory analysis was carried out using the expert sensory profiling technique. The results regarding the olfactory analysis of the extracts allowed us to define the aroma profiles of the four extracts, highlighting their strong correspondence with the characteristic of the varieties under investigation. Finally, the results showed that the aqueous extracts produced using the Synergy Pure extraction technique had a richer aroma profile, highlighting its higher aptitude in beer production. [ABSTRACT FROM AUTHOR]

Fruit wine is one of the oldest fermented beverages made from non-grape fruits. Owing to the differences in fruit varieties, growing regions, climates, and harvesting seasons, the nutritional compositions of fruits (sugars, organic acids, etc.) are different. Therefore, the fermentation process and microorganisms involved are varied for a particular fruit selected for wine production, resulting in differences in volatile compound formation, which ultimately determine the quality of fruit wine. This article reviews the effects of various factors involved in fruit wine making, especially the particular modifications differing from the grape winemaking process and the selected strains suitable for the specific fruit wine fermentation, on the formation of volatile compounds, flavor and aroma profiles, and quality characteristics of the wine thus produced. Key points: • The volatile profile and fruit wine quality are affected by enological parameters. • The composition and content of nutrients in fruit must impact volatile profiles. • Yeast and LAB are the key determining factors of the volatile profiles of fruit wines. [ABSTRACT FROM AUTHOR]

Quinoa is a full‐nutrition food; however, its poor flavor and small size make it not the best food option for direct consumption. In this study, a quinoa snack (QS, a cake) was developed, and the aroma profile of the products was improved by adding jujube fruit powder (made from dried jujube fruits, from 5% to 30%). Gas chromatography mass spectrum (GC–MS) combined with electronic nose (e‐nose) was applied for characterizing the aroma profiles of QS samples. Results showed a total of 26 aroma compounds were identified in QS samples by GC–MS, and 3‐methylbutanol (from 1525 μg/kg in QS‐30 to 3487 μg/kg in QS‐0), ethanol (from 1126 μg/kg in QS‐0 to 3581 μg/kg in QS‐30), hexanal (from 125.6 μg/kg in QS‐30 to 984.1 μg/kg in QS‐0), and acetaldehyde (from 531.9 μg/kg in QS‐30 to 191.1 μg/kg in QS‐0) were common. The e‐nose response of W1S (sensitive to methane, from 17.50 of QS‐0 to 93.85 of QS‐30) and W1W (sensitive to sulfur‐organic compounds of e‐nose, from 15.57 of QS‐0 to 39.50 of QS‐30) were significantly higher, and significant differences were presented among QS samples. In conclusion, the aroma profile of the QS sample was significantly (p <.05) enhanced by the addition of jujube powder, and QS‐30 with the highest jujube content (30%) presented the strongest aroma profile. Moreover, QS samples with different additions of jujube powders could be well distinguished by principal component analysis (PCA), and the combination of e‐nose and GC–MS was effective in the volatile profile analysis of QS samples. [ABSTRACT FROM AUTHOR]

This research aimed to analyze the impact of two different non-Saccharomyces yeast species on the aromatic profile of red wines made from the cv. Babić (Vitis vinifera L.) red grape variety. The grapes were obtained from two positions in the Middle and South of Dalmatia. This study compared a control treatment with the Saccharomyces cerevisiae (Sc) strain as a type of sequential inoculation treatment with Lachancea thermotolerans (Lt x Sc) and Torulaspora delbrueckii (Td x Sc). The focus was on the basic wine parameters and volatile aromatic compound concentrations determined using the SPME-Arrow-GC/MS method. The results revealed significant differences in cis-linalool oxide, geraniol, neric acid, and nerol, which contribute to the sensory profile with floral and rose-like aromas; some ethyl esters, such as ethyl furoate, ethyl hexanoate, ethyl lactate, ethyl 2-hydroxy-3-methylbutanoate, ethyl 3-hydroxy butanoate, diethyl glutarate, and diethyl succinate, contribute to the aromatic profile with fruity, buttery, overripe, or aging aromas. A sensory evaluation of wines confirmed that Td x Sc treatments exhibited particularly positive aromatic properties together with a more intense fullness, harmony, aftertaste, and overall impression. [ABSTRACT FROM AUTHOR]

This study tested the effect of Companilactobacillus paralimentarius E-106, Lactiplantibacillus paraplantarum N-15 and Lactiplantibacillus plantarum SC-9 on the amount of Maillard reaction and aroma profile in bread making with main bread quality parameters. The specific volumes of sourdough and control breads were in the range of 2.97–3.04 cm3/g, and the control II bread had the highest hardness values on all days. The FAST index value was determined to be between 40.48% and 81.22% in all breads. The FAST index value was found to be higher in the control breads than in the sourdough breads. In the volatile compounds analysis, 72 volatile compounds were detected. The variety of volatile compounds in the breads with sourdough addition was higher than the control breads. Among the tested strains, Companilactobacillus paralimentarius E-106 demonstrated superior properties for bread characteristics in comparison to other strains as a type II sourdough starter. In summary, improved aroma profile and decreased Maillard reaction products can be provided by sourdough addition without changing the bread quality, along with meeting consumer demand for less additive use. [ABSTRACT FROM AUTHOR]

Spirulina platensis (SP) has gained popularity over the last few years, owing to its remarkable nutritional properties and high potential across various industrial sectors. In this study, we analyzed the volatile profile of eight SP samples from the same strain subjected to different drying (oven-drying, air-drying, and spray-drying) and storing conditions ("freshly prepared" and after 12 months of storage) using HS-SPME-GC-MS. Principal component analysis (PCA) was used as a multivariate technique to discern similarities and differences among the samples. The main aim was to assess the impact of the drying technique on the aroma profile and storage life of SP samples. Air-drying leads to the less pronounced formation of by-products related to heat treatment, such as Maillard and Strecker degradation compounds, but promotes oxidative and fermentative phenomena, with the formation of organic acids and esters, especially during storage. Thermal treatment, essential for limiting degradation and fermentation during storage and extending shelf life, alters the aroma profile through the formation of volatile compounds, such as Strecker aldehydes and linear aldehydes, from amino acid and lipid degradation. High temperatures in spray-drying favor the formation of pyrazines. The findings underscore the trade-offs inherent in choosing an appropriate drying method, thereby informing decision-making processes in industrial settings aimed at optimizing both product quality and efficiency. [ABSTRACT FROM AUTHOR]

Abstract Herbal spices are widely consumed as food additives owing to their distinct aroma and taste as well as a myriad of economic and health value. The aroma profile of four major spices including bay leaf, black pepper, capsicum, and fennel was tested using HS-SPME/GC–MS and in response to the most widely used spices´ processing methods including autoclaving and γ-radiation at low and high doses. Additionally, the impact of processing on microbial contamination of spices was tested using total aerobic count. GC–MS analysis led to the identification of 22 volatiles in bay leaf, 34 in black pepper, 23 in capsicum, and 24 in fennel. All the identified volatiles belonged to oxides/phenols/ethers, esters, ketones, alcohols, sesquiterpene and monoterpene hydrocarbons. Oxides/phenol/ethers were detected at high levels in all tested spices at ca. 44, 28.2, 48.8, 61.1%, in bay leaves, black pepper, capsicum, and fennel, respectively of the total blend and signifying their typical use as spices. Total oxides/phenol/ethers showed an increase in bay leaf upon exposure to γ-radiation from 44 to 47.5%, while monoterpene hydrocarbons were enriched in black pepper upon autoclaving from 11.4 in control to reach 65.9 and 82.6% for high dose and low dose of autoclaving, respectively. Cineole was detected in bay leaf at 17.9% and upon exposure to autoclaving at high dose and γ-radiation (both doses) its level increased by 29–31%. Both autoclaving and γ-radiation distinctly affected aroma profiles in examined spices. Further, volatile variations in response to processing were assessed using multivariate data analysis (MVA) revealing distinct separation between autoclaved and γ-radiated samples compared to control. Both autoclaving at 115 °C for 15 min and radiation at 10 kGy eliminated detected bioburden in all tested spices i.e., reduced the microbial counts below the detection limit (

The objective of this study was to investigate the impact of co-fermentation of Italia and Negra Criolla grape musts using non-Saccharomyces yeast strains (NSYSs) isolated from both grape varieties, on the major volatile compounds and sensory characteristics of Piscos (distilled spirits). Native NSYSs previously isolated from Italia (Pichia terricola, Metschnikowia pulcherrima, and Naganishia vaughanmartiniae) and Negra Criolla (Vishniacozyma carnescens, Vishniacozyma heimaeyensis, and Aureobasidium pullulans) grapes’ skins were inoculated at the beginning of grape must fermentation. A centroid simplex design was applied in order to obtain 10 representative yeast blends for use as mono- (n = 3), bi- (n = 3), and ternary (n = 4) inoculations. Additionally, a control sample without inoculum was also set up. For each yeast blend, the volatile composition and sensory characteristics of Piscos were evaluated. Results showed that mono-inoculation using specific NSYSs, such as P. terricola, M. pulcherrima, and N. vaughanmartiniae, led to a notable predominance of some terpenes such as α-terpineol, citronerol, and geraniol in Pisco from Italia grapes compared to the control Pisco. Conversely, in Pisco from Negra Criolla grapes, where V. carnescens, V. heimaeyensis, and A. pullulans were used in a similar mono-inoculation process, a higher presence of phenylethyl alcohol and 2-phenylethyl acetate compared to the control was observed. The sensory analysis revealed that citrus, floral, alcohol, and syrup descriptors had a higher intensity in mono-inoculated Pisco Italia, whereas spice, herbaceous, and cooked vegetable descriptors had the highest intensity in Negra Criolla Piscos produced with ternary NSYS inoculum inoculations. This study demonstrates that the use of native non-Saccharomyces yeast strains in the co-fermentation of grape musts can significantly influence the volatile profile and sensory characteristics of Pisco. These findings will allow us to establish new inoculation strategies to impact the overall sensory and aromatic profile of the Piscos produced with different grape varieties.

Guava is a high-value tropical fruit that is widely grown in tropical and subtropical regions around the world. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. The use of seedlings in cultivation created a genetic variation and differences were observed between the resulting genotypes, especially in terms of fruit size, shape and colour. Based on this observation, this study aimed to characterize 13 different guava fruit genotypes based on physical, chemical, bioactive and aroma properties. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. There is only one commercial variety namely 'Ruby Supreme' grown in Turkey. Presently, the interest of the guava cultivation has been increased and farmers were used seedling material instead of vegetative to establish orchard. Due to the cross pollination, it has been observed great variation in the population. Therefore, it is important to select promising genotypes according to fruit size, shape and colour. The present study was evaluated 13 different guava genotypes according to physical, chemical, bioactive and aroma properties. Significant differences were observed among the genotypes. One genotype was found superior over all the genotypes, in terms of fruit weight (131.44 g) and length (82.00 mm). Although three genotypes were having lower values than the other samples in results of total soluble solids, they had higher results in terms of antioxidant capacity and total phenolic content. Two genotypes formed a separate group from all other genotypes in terms of (Z)-3-Hexen-1-yl acetate (sweet, pear, melon), 3-Hexenal (melon, tropical) and Ethyl alcohol (fruit and sweet) components. The flavor components are distinctive for the guava samples, as are the physical properties. It was also determined that the white guava genotypes had very different chemical and aromatic properties from other genotypes. The promising genotypes can be utilized in the future breeding programme to improve new guava varieties. [ABSTRACT FROM AUTHOR]

In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardaria draba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatile organic compounds (96.7%-98.9%) were identified; 4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones, 1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the main group, representing 49.5%-84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane (44.5%-76.2%) reaching the highest relative percentages. Forty-two compounds were determined in the two fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal components were hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermis using light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces and nearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes were anisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandular trichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones were identified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatal index (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essential oil compounds can be used to characterize this species, and the various epidermis micromorphological features are very useful for biosystematics taxonomic studies within Brassicaceae. [ABSTRACT FROM AUTHOR]

The growing interest in functional foods is driven by the exploration of new foods with positive health effects. Pleasant sensory features are essential for consumer acceptance. In this work, we investigated the composition of the bioactive compounds, antioxidant activity, and aroma profiles of four edible flowers: Cucurbita moschata Duchesne, Dianthus chinensis L., Fuchsia regia (Vand. ex Vell.) Munz., and Viola cornuta L. For the first time, we quantified the water-soluble group of B vitamins. Significant variations in the content of soluble sugars, vitamins, and secondary metabolites were observed. V. cornuta showed the highest concentration of vitamin C and carotenoids, while C. moschata had the highest content of vitamin B and flavonoids. F. regia stood out for its exceptionally high content of total phenolics, while D. chinensis surpassed the other flowers in soluble sugar content. The aroma profile analysis revealed a diverse array of volatile organic compounds, with each species having its own unique composition. C. moschata was characterized by p-dimethoxybenzene and D. chinensis by non-terpene compounds; F. regia displayed high amounts of decanal and nonanal, while V. cornuta was rich in myrcene and α-farnesene. These findings provide valuable insights into the secondary metabolites and aroma profiles of these flowers, enhancing our understanding of their bioactive compounds and potential health benefits. [ABSTRACT FROM AUTHOR]

The prevailing climate is an important factor affecting the development of the physical quality and flavor of cacao (Theobroma cacao L.) beans. The influence of harvest seasons on the physical, chemical, and flavor characteristics of cacao beans from Nakhon Si Thammarat Province, southern Thailand, was assessed. Among cacao beans, those harvested in the rainy season (R) had the highest fresh and dry weights and the lowest bean count per 100 g (87.00 ± 2.83). Although the overall fat content remained relatively constant across harvest seasons, cacao beans harvested in R exhibited a significantly higher fatty acid (C16:0, C18:1, and C18:2) content than those harvested in the dry season (D). Cacao beans harvested in D displayed a more diverse and intense aroma profile than those harvested in R. Therefore, this study proved that harvest seasons significantly influenced the physicochemical characteristics of cacao beans. Cacao beans harvested in D exhibited more complex and distinct postroasting aroma profiles than those harvested in R. Evaluating the seasonal harvesting of cacao beans is crucial for developing cocoa and chocolate with fine and unique flavors in southern Thailand. [ABSTRACT FROM AUTHOR]

The scope of the present study was to study the effect of different populations of Hermetia illucens, commonly known as black soldier fly (BSF), on the major components and volatile composition of the derived freeze-dried flours. Potential differences in the composition of different life cycle stages of BSF, i.e., larvae and pupae, were also investigated. The flours obtained from larvae of two BSF populations from Greece (GR) and Portugal (PO) (L-GR and L-PO, respectively) demonstrated similar major chemical compositions. Pupae (Pu-PO) were richer in chitin compared to larvae. Differences were spotted in their fatty acid profiles and volatile fractions. The saturated/unsaturated lipid fraction ratio was 1.5 in L-GR, higher in L-PO (2.5), and even higher in the case of Pu-PO (4.0). Seventeen (17) compounds were detected in the volatile fraction of the Pu-PO samples and 24 in the volatile fraction of the L-GR and L-PO samples. Notably, dodecanoic acid ethyl ester was the predominant volatile compound in all samples. The proteins of both larvae and pupae were dominated by β-sheet structures. The present study's findings are valuable for designing food or feed products based on BSF components and could be important for applying suitable manufacturing and processing procedures.

The study reports the presence of 87 free and glycosidically bound volatile compounds in two quince fruit cultivars (Round and Oblong). The major free volatile compounds were ethyl acetate,ethyl (E)-2-butenoate, hexyl butanoate, hexyl 2-methylbutanoate, ethyl 3- phenyl propanoate, α-farnesene, hexanal, 1-hexanol, dihydo-beta-ionol and linalool oxide. The major bound volatiles were ethyl acetate, hexyl pentafluoro propanoate, ethyl hexanoate, γ-elemene, cyclocitral, megastigmatrienone-II and dihydo-beta-ionol. Among all the volatiles, γ-elemene (in glycosidically bound form), cyclocitral, (E)-β-damascenone (in both free and bound form), were found for the first time in quince fruit. Odour activity values (OAVs) of most potent volatiles were calculated for both free and bound volatiles, with 11 compounds having an OAV above 1. Volatiles with higher OAVs in two varieties were β-ionone, (E)-β-damascenone, (Z, E)-α-farnesene, ethyl 2-methyl butanoate and hexanal, with the highest being 425 for (E)-β-damascenone as free form in ‘Round’ variety. In addition, the off-flavours released from quince juice after enzyme treatment or cooking were identified. In particular, megastigmatrienone-II was identified to contribute tobacco flavour. Thus, it can be concluded that variation in free and bound volatiles between the two quince cultivars resulted in the different organoleptic properties, which would assist consumers in selection of the desired quince cultivar.

Aroma plays a pivotal role in defining tea quality and distinctiveness, and tea producers have often observed that specific drought conditions are closely associated with the formation and accumulation of characteristic aroma compounds in tea leaves. However, there is still limited understanding of the differential strategies employed by various tea cultivars in response to drought stress for the accumulation of key volatile aroma compounds in fresh tea leaves, as well as the associated metabolic pathways involved in aroma formation. In this study, two widely cultivated tea cultivars in China, Fuding Dabai (FD) and Wuniuzao (WNZ), were examined to assess the impact of mild field drought stress on the composition and accumulation of key volatile aroma compounds in fresh leaves using headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS) and headspace solid phase micro-extraction gas chromatography–mass spectrometry (HS-SPME-GC-MS) technologies. Results revealed that drought stress led to a substantial increase in the diversity of volatile compounds (VOCs) in FD, while WNZ exhibited a notable rise in low-threshold VOC concentrations, amplifying sweet, floral, fruity, and earthy aroma profiles in post-drought fresh leaves. Through partial least squares discriminant analysis (PLS-DA) of HS-GC-IMS and HS-SPME-GC-MS data, integrating variable importance projection (VIP) scores and odor activity values (OAVs) above 1, 9, and 13, key odor-active compounds were identified as potential markers distinguishing the drought responses in the two cultivars. These compounds serve as crucial indicators of the aromatic profile shifts induced by drought, providing insights into the differential metabolic strategies of the cultivars. Additionally, KEGG enrichment analysis revealed 12 metabolic pathways, such as terpenoid biosynthesis, fatty acid synthesis, cutin, suberine, and wax biosynthesis, and phenylalanine metabolism, which may play crucial roles in the formation and accumulation of VOCs in tea leaves under drought stress. These findings provide a comprehensive framework for understanding the cultivar-specific mechanisms of aroma formation and accumulation in tea leaves under mild drought conditions.

In this study, the change of aroma components in instant Baiyaqilan tea powder during processing was investigated by sensory evaluation, gas chromatography-mass spectrometry (GC-MS) and odor activity value (OAV). The results showed that the over aroma profile and the types of aroma components in instant Baiyaqilan tea powder were similar at different stages of processing, while the aroma intensity and volatile components were significantly different. 3-Ethyl-2,5-dimethylpyrazine, hotrienol, methyl salicylate, safranal, geraniol, indole, β-damascenone, cis-jasmonone, geranyl acetone, trans-nerolidol and methyl jasmonate were found to make key contributions to aroma changes. The extraction process significantly increased the OAV of safranal, geraniol, indole, β-damascenone and cis-jasmonone. Disc separation, reverse osmosis and freeze drying significantly reduced the OAV of geraniol, indole, β-damascenone, cis-jasmonone, methyl jasmonate, trans-nerolidol, 3-ethyl-2,5-dimethylpyrazine and safranal. Moreover, ultrafiltration treatment removed tea polyphenol complexes, promoting the release of aroma volatile compounds combined with polyphenols and thus increasing the OAV of geraniol, indole, β-damascenone, cis-jasmonone and methyl jasmonate. This study clarified the aroma change during the processing of instant Baiyaqilan tea powder and showed that ultrafiltration treatment promoted the release of aromatic volatiles. This study can provide a theoretical basis for improving the processing of instant Baiyaqilan tea powder for improved aroma quality and the processing technology of instant tea.

The effect of ultrasound (US) applied before (US + i) and after (i + US) inoculation of yoghurt starter into cows' milk on some parameters of yoghurt was investigated. Lightness (L*) values, amounts of acetaldehyde, diacetyl, acetoin, ethanol, lactic, pyruvic, and acetic acid were higher in the US‐treated groups compared with control (P < 0.05). In the US + i group, the total amount of ketones increased. Lactobacillus and Streptococcus spp. numbers reached log ≥7.0 cfu/g in all groups (P > 0.05). It can be concluded that low‐intensity ultrasound applied to cows' milk before or after inoculation of yoghurt starters increases the aroma components and organic acid content of yoghurt. [ABSTRACT FROM AUTHOR]

In order to investigate the differences of aroma components and aroma profiles in segmented smoke of cigars, gas chromatography-mass spectrometry (GC-MS) was used to detect the aroma compounds of Great Wall No. 2 and Montecristo No. 4 cigars, supplemented by sensory evaluation and odor contribution weight to investigate the aroma characteristics of cigars, and the key aroma components in cigars were screened based on partial least squares discriminant analysis (PLS-DA). The results showed that the cigar was shorter, the interception effect was weakened, and the quantity and release of aroma components in cigar smoke were increased during smoking. In the odor contribution weight of segmented smoke of cigars, the bean and woody aromas of Great Wall No. 2 weakened and the coffee aroma increased as smoking proceeded, while the bean aroma of Montecristo No. 4 weakened and the spicy aroma increased. These changes in odor contribution weight were consistent with the results of the sensory evaluation. 12 key differential aroma components such as γ-hexalactone, 2-furoic acid, acetophenone, phenylacetic acid, 2,6-dimethylpyrazine were obtained during the smoking process of Great Wall No. 2, and 11 key differential aroma components such as cedrol, 2-methylbutyraldehyde, 2-methoxy-4-vinylphenol, guaiacol, γ-nonanolactone were obtained during the smoking process of Montecristo No. 4. The results of this study reflected the change rules of smoke composition in the smoking process of cigar and explained the reasons for the flavor changes in the smoking process of cigar. [ABSTRACT FROM AUTHOR]

In this study, the influence of the essential oil extracted from dill fruits and fronds on lactic acid bacteria, aroma profile and sensory characteristics of the obtained yoghurt was investigated. The addition of essential oils in amounts of 30 µl kg-1 fermented milk affects the pH and aroma profile, which is due to the different compositions of the oils. The obtained yoghurts were sensory well evaluated by the testers during the tasting performed. [ABSTRACT FROM AUTHOR]

Jasmine tea is loved by most people who drink flower tea owing to its unique aroma, and it is known as the top of flower teas. In our study, the quantitative evaluation of the quality of jasmine tea and detection of aroma components were carried out. First, the flavor quality of 92 kinds of jasmine tea was evaluated using multiple sub‐factor quality evaluation methods. According to the evaluation results, jasmine tea was divided into three types: "fresh and lovely" (FL), "heavy and thick" (HT), and "fresh and heavy" (FH). Gas chromatography–mass spectrometry (GC–MS) was used to detect the aroma components of the three types of jasmine tea samples. α‐Farnesene, cis‐3‐hexenyl benzoate, acid phenylmethyl ester, linalool, methyl anthranilate, and indole were the main substances that constituted the basic aroma quality characteristics of jasmine tea. Compared to the FL type, the HT and FH types were weaker in the diversification of the characteristic aroma and accumulation of green, herb, sweet, and roast aroma substances. Green and herb aromas play crucial roles in the fresh and persistent qualities of the three types of jasmine tea, which are the key quality factors research focus of jasmine tea. [ABSTRACT FROM AUTHOR]

Yield and aroma stability under drought in indigenous aromatic rice cultivars (IARCs), which needs significant attenuation of reduction of grain yield and quality through redox metabolic reprograming in contributory flag leaf was rarely studied and hence was the subject of present investigation. The redox landscaping of flag leaves of experimental IARCs done (Oryza sativa L., Cultivars Tulaipanji, Badshabhog, Jamainadu, and Sitabhog) during ensuing drought stress at grain-filling stage (65% of field capacity) and stress withdrawal (after 6 days) revealed tilt in the magnitude of redox homeostasis (assessed in terms of oxidation of DCFDA, accumulation of O2⋅−, H2O2, free radical scavenging property, non-protein thiol compounds, redox osmolytes, antioxidant pigments, and ROS-antioxidant interaction index), efficacy of RboH- ascorbate–glutathione/catalase pathway and sensitive biomarkers oxidative stress (accumulation of free carbonyl compounds, hydroperoxide, conjugated diene, and thiobarbituric acid reactive substances). The Cultivars capable of regulating ROS-antioxidant interaction dynamics at metabolic interface in flag leaf (Badshabhog and Tulaipanji) and able to prevent oxidative deterioration of flag leaf caused better restoration of aroma profile, 2-acetyl-1-pyrroline (2AP) content, agronomic characters, seed yield, and kernel quality than the others (Jamainadu and Sitabhog). Further, germplasm specific comparative assessment of metabolites shared by redox osmolyte proline and (2AP), exhibited metabolic cross talking toward regulation of dehydration induced oxidative stress and restoration of aroma production. Ability of maintenance of aromatic compounds, agronomic characters, seed yield, and kernel quality under drought stress through redox-regulatory acclimatory events of flag leaves in IARCs is suggested. [ABSTRACT FROM AUTHOR]

Aqueous extracts from four different American hops varieties (Mosaic, Chinook, Citra, and Centennial) were produced using the Synergy Pure technique, an innovative extraction distillation process developed by Synergy Flavours, a global specialist in the manufacturing of flavors, extracts and essences. This process is able to preserve and maximize the aromatic characteristics without increasing the bitterness of the final product. Therefore, the aim of this work is to identify the volatile and sensory characteristics of these extracts, with the additional aim to assess their suitability for brewing. GC-MS and sensory analyses were carried out on the four different aqueous extracts. The results highlighted the presence of 33 volatile compounds in a quantity that allowed us to identify the characteristics of the varieties under investigation in each extract. Sensory analysis was carried out using the expert sensory profiling technique. The results regarding the olfactory analysis of the extracts allowed us to define the aroma profiles of the four extracts, highlighting their strong correspondence with the characteristic of the varieties under investigation. Finally, the results showed that the aqueous extracts produced using the Synergy Pure extraction technique had a richer aroma profile, highlighting its higher aptitude in beer production.

This study tested the effect of Companilactobacillus paralimentarius E-106, Lactiplantibacillus paraplantarum N-15 and Lactiplantibacillus plantarum SC-9 on the amount of Maillard reaction and aroma profile in bread making with main bread quality parameters. The specific volumes of sourdough and control breads were in the range of 2.97–3.04 cm3/g, and the control II bread had the highest hardness values on all days. The FAST index value was determined to be between 40.48% and 81.22% in all breads. The FAST index value was found to be higher in the control breads than in the sourdough breads. In the volatile compounds analysis, 72 volatile compounds were detected. The variety of volatile compounds in the breads with sourdough addition was higher than the control breads. Among the tested strains, Companilactobacillus paralimentarius E-106 demonstrated superior properties for bread characteristics in comparison to other strains as a type II sourdough starter. In summary, improved aroma profile and decreased Maillard reaction products can be provided by sourdough addition without changing the bread quality, along with meeting consumer demand for less additive use.

This research aimed to analyze the impact of two different non-Saccharomyces yeast species on the aromatic profile of red wines made from the cv. Babić (Vitis vinifera L.) red grape variety. The grapes were obtained from two positions in the Middle and South of Dalmatia. This study compared a control treatment with the Saccharomyces cerevisiae (Sc) strain as a type of sequential inoculation treatment with Lachancea thermotolerans (Lt x Sc) and Torulaspora delbrueckii (Td x Sc). The focus was on the basic wine parameters and volatile aromatic compound concentrations determined using the SPME-Arrow-GC/MS method. The results revealed significant differences in cis-linalool oxide, geraniol, neric acid, and nerol, which contribute to the sensory profile with floral and rose-like aromas; some ethyl esters, such as ethyl furoate, ethyl hexanoate, ethyl lactate, ethyl 2-hydroxy-3-methylbutanoate, ethyl 3-hydroxy butanoate, diethyl glutarate, and diethyl succinate, contribute to the aromatic profile with fruity, buttery, overripe, or aging aromas. A sensory evaluation of wines confirmed that Td x Sc treatments exhibited particularly positive aromatic properties together with a more intense fullness, harmony, aftertaste, and overall impression.

The study employed gas chromatography-ion mobility spectrometry to differentiate between wines undergoing spontaneous fermentation and inoculated fermentation, with aging periods of 3, 9, and 15 months. The results indicate that throughout the three aging periods, there was a notable increase in the levels of ethyl hexanoate (Monomer, M), 2-methyl butanal, ethyl octanoate (M), ethyl octanoate (Dimer, D), propyl acetate, and 3-methylbutanal in the spontaneous Italian Riesling wine (RS). Furthermore, the compounds isoamyl acetate (M), ethyl formate (D), 4-methyl-2-pentanone (M), and ethyl formate (M) demonstrated the highest concentrations at 15 months in RS, accordingly, these compounds displayed a consistent upward trend throughout the aging period. A total of 14 volatile compounds exhibited an upward trend from 3 to 15 months in the spontaneous fermentation of Petit Verdot Wine (VS). Subsequently, these compounds attained their maximum levels. Spontaneous fermentation effectively enhances the aromatic characteristics of wines, consequently improving their capacity for aging.

Specialty coffees from various geographical origins were processed using different extraction methods. Four extraction techniques were employed: cold brew (CB), espresso (ES), French press (FR), and aeropress (AE). The potential health benefits of coffee brews were linked to their antioxidant activity, as determined by the DPPH assay, and total polyphenol content (TPC) measured through the Folin–Ciocalteu reducing-capacity assay. The Columbia (C) espresso coffee type (omni-roasting) exhibited the highest antioxidant activity (86.31 ± 0.70) μmol/100 mL, with a TPC value of (44.41 ± 0.35) mg GAE/g. Quantitative analyses of caffeine and chlorogenic acid were conducted using high-performance liquid chromatography (HPLC). The evaluation of coffee aroma profiles involved the application of headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC-MS) and was complemented by sensory analysis following the Specialty Coffee Association (SCA) standard protocol. The predominant volatile compounds found in all samples included furans, phenols, pyrazines, and terpenes. The EY espresso type (medium dark roasting) had the highest levels of most coffee volatiles. The C cold brew type (omni-roasting) was rated as the preferred coffee in terms of its sensory characteristics and flavour. In summary, ES and CB were found to be more effective extraction methods for the parameters assessed. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing interest in natural products of plant origin as herbal remedies. In this study, the profile of bioactive volatile organic compounds and odorous compounds in a sample of Pistacia lentiscus L. vegetable oil has been determined. The study indicated that the oil extraction yield is influenced by the method, the extraction conditions, the stage of maturity of plant and the sampling area. Analysis by HS‐SPME‐GC–MS and GC–MS showed that monoterpenes and sesquiterpenes represent the most numerous groups among the 57 compounds identified. The most abundant compounds are beta‐myrcene, d‐limonene and linoleic acid ethyl ester. Among other compounds humulene, caryophyllene, a‐muurolene and copaene have been detected known for facilitating wound healing. Moreover, β‐caryophyllene and α‐humulene with anti‐inflammatory effects have been determined. 38 different odorous compounds with herbal, citrus and vegetable aromas were detected by panellists using HS‐SPME‐GC‐O‐MS. Research confirmed that the analysed samples have only pleasant aromas that make it a perfect active agent for medicinal use and may gain acceptance of consumers. [ABSTRACT FROM AUTHOR]

This study aimed to compare the aroma profiles of Sorbara and Spergola grapevine prunings roasted at different temperatures (120, 140, 160, 180, 200, and 240 °C). One potential application of grapevine prunings is their use as infusion chips to enhance and improve the aging processes of alcoholic beverages and vinegars. Aromatic compounds impart unique flavors and contribute to the complexity of the final products. Thermogravimetry–mass spectrometry coupled with evolved gas analysis (TGA-MS-EGA) was conducted to identify the thermal steps at which substantial changes occurred in the wood matrix. Solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) was used for the analysis of volatile compounds. Several key volatile compounds were identified, showing variations in their concentrations as a function of cultivar and roasting temperature. Furan derivatives, such as furfural, and phenolic compounds, such as guaiacol and vanillin, were the two main chemical classes of volatile compounds that predominantly defined the aroma of grapevine chips roasted above 180 °C. At lower roasting temperatures, some aldehydes, such as hexanal and terpenes, defined the aroma profiles of the samples. By repurposing waste materials, this application offers a pathway for environmentally conscious viticulture and sustainable practices within the food industry. [ABSTRACT FROM AUTHOR]

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The physicochemical, rheological, aroma, and sensory properties of spreadable processed cheese supplemented with chia, quinoa, and teff seeds were evaluated. The changes in proximate composition, color values, rheological parameters, volatile profile, sensory, and microbiological properties of the cheese samples stored at 4 °C for 90 days were assessed. Significant differences in the initial contents of dry matter, protein, and fat were observed among the cheese samples. The pH was affected by the storage time and type of added pseudocereal. Moreover, the storage time and type of pseudocereal interaction affected the titratable acidity and color parameters of the cheese samples. The water-soluble nitrogen content increased slightly in all cheese samples during storage. The cheese samples supplemented with pseudocereals exhibited a pseudoplastic behavior. The consistency index of the cheese samples ranged from 2.277 to 2.550 Pa.sn, and the flow behavior index ranged from 0.528 to 0.665. The counts of total coliform and yeast-mold in all cheese samples were

Bee honey has different volatile organic compound profiles that depend on the botanical origin and the state of conservation and which are mainly responsible for its specific aroma. During honey storage, the profile of these molecules and other indicators, such as 5-hydroxymethylfurfural and the diastatic index, can change depending on temperature and time. This study analyzed the variations that these parameters in acacia honey stored at three different temperatures for a total period of 550 days, using gas chromatography coupled with mass spectrometry and an electronic nose equipped with 10 different sensors. The results confirm that the composition of acacia honey varies over time due to both the reduction in the concentration of volatile molecules (e.g., formic acid, a natural acaricide) and the increase in compounds resulting from heat-dependent degradations (e.g., 5-hydroxymethylfurfural). This study supports the usefulness of the electronic nose for the early detection of aromatic alterations in honey subjected to high-temperature storage. [ABSTRACT FROM AUTHOR]

BACKGROUND: Steamed bread is a popular staple food in China, and the significant regional differences of the microbiota in traditional starters make the flavor and quality of steamed bread highly variable along with long preparation times. Therefore, analyzing the microbial flora of traditional starters and their influences on the flavor and quality may help to solve the problems mentioned earlier, and it may also be conducive to potentially meet consumer needs and permit industrialization of this traditional fermented food. RESULTS: One hundred and thirty‐two fungal and 50 bacterial species were identified in five traditional starters, each with a different dominant genus. The fermentation properties of dough showed that total titratable acid, dough volume and gas production increased and the pH decreased with fermentation time. The traditional starters improved the quality of Chinese steamed bread (CSB) including the crumb structure, specific volume and sensory attributes. Thirty‐three aroma compounds with a VIP (variable importance for the projection) > 1 were identified as characteristic aroma compounds. The correlations among the microbiota, aroma and qualities of CSB showed a greater contribution from the bacteria, which was consistent with the predictions of metabolic pathways in the sequenced genomes. CONCLUSION: The quality of CSB fermented with traditional starters was improved induced by their different microbial profiles, and bacteria made a greater contribution than fungus to the aroma and qualities of CSB. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Pineapple juice was added at three different points in the brewing process, (i) wort, (ii) toward the end of fermentation and (iii) at the beginning of maturation. The physicochemical properties, taste and aroma of the three fruit beers was compared to a control beer without addition of pineapple juice. The beers were analysed using an electronic nose (E-nose), head space solid phase micro-extraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and head space gas chromatography-ion mobility spectrometry (HS-GC-IMS). Of the three fruit beers, esters characteristic of pineapple aroma was found in the beer produced with juice added late during primary fermentation. Further, the abundance of esters-isoamyl acetate, ethyl butyrate, ethyl acetate, ethyl hexanoate and phenethyl acetate-was higher. Sensory analysis showed the beer produced from the addition of juice late in fermentation had a superior aroma and was the most preferred in sensory testing. These results provide technical support for process optimisation and for improving the aroma of fruit beers. [ABSTRACT FROM AUTHOR]

The majority of chemical compounds that contribute to varietal aroma originate from grape skin. To investigate the differences between volatile aroma compounds when different maceration conditions are applied, a total of six vinification treatments were carried out on Malvazija istarska (Vitis vinifera L.) variety, non-maceration control treatment (C), pre-fermentative two days cryomaceration treatment at 8 °C (CRYO), seven days maceration treatment at 16 °C (M7), 14 days maceration treatment at 16 °C (M14), and prolonged post-fermentative maceration treatments at 16 °C for 21 day (M21) and 42 days (M42). Wines were subjected to GC/MS and sensory analysis. Obtained results showed that prolonged post-fermentative maceration treatments contained the highest concentration of total volatile aroma compounds, precisely monoterpenes, alcohols, and other esters. Contrary, C and CRYO wines resulted in highest concentration of ethyl and acetate esters, and fatty acids. In addition, sensory analysis showed that longer maceration treatment wines (M14, M21, M42) were characterized by more aroma complexity, varietal flowery typicity, pronounced fruitiness, with accentuated dried fruit, moderate honey, and herbal notes. Obtained results can provide valuable information to producers when choosing an appropriate vinification technique based on the desired wine style which may lead to a further diversification of white wine market. [ABSTRACT FROM AUTHOR]