Search Results (43)

This paper introduces a novel multi-objective optimization framework for sustainable portfolio rebalancing under uncertainty. The model simultaneously targets return maximization, downside risk control, and liquidity preservation, addressing the complex trade-offs faced by investors in volatile markets. Unlike traditional static approaches, the framework allows for dynamic asset reallocation and explicitly incorporates nonlinear transaction costs, offering a more realistic representation of trading frictions. Key financial parameters—including expected returns, volatility, and liquidity—are modeled using interval arithmetic, enabling a flexible, distribution-free depiction of uncertainty. Risk is measured through semi-absolute deviation, providing a more intuitive and robust assessment of downside exposure compared to classical variance. A core innovation lies in the behavioral modeling of investor preferences, operationalized through three strategic configurations, pessimistic, optimistic, and mixed, implemented via convex combinations of interval bounds. The framework is empirically validated using a diversified cryptocurrency portfolio consisting of Bitcoin, Ethereum, Solana, and Binance Coin, observed over a six-month period. The simulation results confirm the model’s adaptability to shifting market conditions and investor sentiment, consistently generating stable and diversified allocations. Beyond its technical rigor, the proposed framework aligns with sustainability principles by enhancing portfolio resilience, minimizing systemic concentration risks, and supporting long-term decision-making in uncertain financial environments. Its integrated design makes it particularly suitable for modern asset management contexts that require flexibility, robustness, and alignment with responsible investment practices. Full article

This study investigated the effect of the water content of large yellow croaker fillets on their quality characteristics after roasting. The large yellow croaker fillets were randomly divided into groups, namely, the fresh group (BMC-77), the 3% salt-cured group (BMC-70), and groups cured with 3% salt followed by hot air drying to obtain different moisture contents (BMC-65, BMC-60, and BMC-55). Then, the fillets were roasted at 220 °C for 20 min. There were four replicates for each group. Various indicators, including color, texture, thiobarbituric acid-reactive substance (TBARS) content, total volatile basic nitrogen (TVB-N) content, water distribution, volatile components, and myofibrillar proteins were determined, and a sensory evaluation was carried out. The results showed that as the water content decreased, the lightness (L*) of the roasted fillets significantly decreased (p < 0.05), while the redness (a*) and yellowness (b*) increased. The hardness, shear force, TBARS, and TVB-N values all increased significantly (p < 0.05). The proportion of immobile water decreased, while the proportions of tightly bound water, free water, and loosely bound water increased. The electronic nose, electronic tongue, and GC-MS analyses revealed that there were significant differences in odor, taste, and volatile components among fillets with different water contents. A comprehensive analysis of all the indicators demonstrated that the fillets with an initial water content of 65% (BMC-65) achieved the best sensory qualities after roasting in terms of taste and flavor. An appropriate reduction in the initial water content helped to improve the texture and appearance of the fillets while delaying the degradation of proteins and lipids. This study provides a theoretical foundation for optimizing the roasting process of large yellow croaker fillets. Future research could explore the synergistic effects of the roasting conditions and water content to achieve more accurate quality control. Full article

Dragon fruit (Hylocereus spp.), a globally popular tropical fruit, is highly regarded for its unique sensory attributes and potential health benefits. However, the volatile organic compound (VOC) profiles that define its aroma and flavor are underexplored. This exploratory study investigates the VOC profiles of Australian-grown and imported dragon fruit, focusing on free volatiles and glycosidically bound volatiles released through acid and enzymatic hydrolysis. The analysis aims to uncover the competitive advantages of Australian-grown dragon fruit, providing a scientific foundation for establishing industry standards in Australia, where such standards are currently absent. Using gas chromatography–mass spectrometry (GC-MS) and statistical analysis such as principal component analysis (PCA), this study revealed significant differences in VOC profiles influenced by variety and growing region. Northern Territory-grown white-fleshed dragon fruit (NTW) displayed the most diverse and unique volatile profile, with key unique contributors such as acetoin, phenylethyl alcohol, and prenol, highlighting its potential as a premium product. Despite regional similarities, Queensland-grown white- (QLDW) and red-fleshed (QLDR) dragon fruit exhibited distinct profiles, with compounds such as farnesol and linoleic acid ethyl ester serving as distinguishing markers. Overseas white- (OverseasW) and red-fleshed (OverseasR) samples had less complex profiles, likely related to earlier harvesting and postharvest treatments, emphasizing the impact of such practices on volatile complexity. Glycosidically bound volatiles were identified as latent precursors that enhance aroma during ripening and processing. This research underscores the importance of VOC profiling in potentially assisting with establishing industry standards for Australian dragon fruit, enabling the differentiation of domestic varieties from imports and enhancing market competitiveness. As this is a novel and exploratory study, future research should prioritize the identification of unknown compounds and refine methodologies to better understand the dynamic changes in VOCs during storage and ripening. These findings provide valuable insights for optimizing postharvest practices and developing standards that support the Australian dragon fruit industry’s growth and global positioning. Full article

The study aimed to investigate the effects of pre-treatment (husking, sifting, and moisture adjustment) and explosion puffing on the chemical composition, volatile profile, phenolic content (free and bound), radical-scavenging activity, and formation of potentially hazardous compounds in wheat grain. Processing decreased protein, fat, ash, and dietary fiber content primarily due to removing the aleurone layer and thermal degradation leading to a diminished overall nutritional value. However, the starch content increased, along with significant changes in mono- and disaccharides, including higher maltose and glucose content attributed to starch gelatinization and hydrolysis. Thermal processing significantly altered the volatile profile, introducing new aroma-active compounds, such as pyrazines and furans, formed through Maillard and caramelization reactions. Additionally, the content of spectrophotometrically determined free phenolics and flavonoids increased, enhancing the grains’ radical-scavenging potential. Safety analyses confirmed that 5-hydroxymethylfurfural (5-HMF) and acrylamide levels remained within permissible limits, ensuring compliance with food safety standards. These findings highlight the nutritional and safety implications of explosion puffing, emphasizing its potential as a wheat-processing method. Full article

Shiikuwasha, a citrus fruit native to Okinawa, Japan, has various cultivation lines with distinct free volatile and non-volatile components. However, the glycosylated volatiles, which are sources of hidden aromas, remain unknown. This study aimed to characterize the chemical profiles of free and glycosidically bound volatile as well as non-volatile components in the mature fruits of six Shiikuwasha cultivation lines: Ishikunibu, Izumi kugani-like, Kaachi, Kohama, Nakamoto seedless, and Ogimi kugani. Free volatiles were analyzed using solid-phase microextraction–gas chromatography–mass spectrometry. Glycosides were collected via solid-phase extraction and hydrolyzed with β-glucosidase, and the released volatiles were measured. Additionally, the non-volatile components were determined using non-targeted proton nuclear magnetic resonance analysis. Total free and bound volatiles ranged from 457 to 8401 µg/L and from 104 to 548 µg/L, respectively, and the predominant free volatiles found were limonene, γ-terpinene, and p-cymene. Twenty volatiles were released from glycosides, including predominant 1-hexanol and benzyl alcohol, with Kaachi and Ogimi kugani showing higher concentrations. Principal component analysis (PCA) revealed that taste-related compounds like sucrose, citrate, and malate influenced line differentiation. The PCA of the combined data of free and bound volatile and non-volatile components showed flavor component variances across all lines. These findings provide valuable insights into the chemical profiles of Shiikuwasha fruits for fresh consumption and food and beverage processing. Full article

Vitis vinifera L. is a commercially important horticultural plant with abundant microbial resources. However, the impact of grape-associated microbiota on grape quality and flavor has been largely overlooked. We integrated volatomics and microbiomics to explore temporal variations in berry volatiles and microbial diversity of ‘Cabernet Sauvignon’ in Ningxia (NX) and Shanxi (SX), and the correlation between microbial communities and volatiles. A total of 38 and 35 free and bound aroma compounds, respectively, were identified in NX berries and SX berries. For free aroma, these 38 compounds were classified into aldehydes (69%), alcohols (22%), acids (4%), aromatics (4%), terpenes (0.6%), esters (0.37%), and norisoprenoids (0.3%). Similarly, the 35 bound aromas were attributed to aromatics (58%), acids (29%), terpenes (4%), esters (3%), alcohols (2.82%), aldehydes (2.78%), and norisoprenoids (0.4%). Additionally, a total of 616 bacterial genera and 254 fungal genera were detected in all samples from both regions. The results demonstrated that vineyard sites significantly shaped the characteristics of berry volatiles and microbial biogeographic patterns. SX berries exhibited more abundant free aroma and higher microbial diversity than NX berries, with three key taxa (Sphingomonas, Massilia, and Bacillus) identified in the bacterial network. Correlation analysis results highlighted that these key taxa might play an important role in berry-free aroma. This study reveals the crucial role of microbes in shaping grape flavor and uncovers the link between microbial diversity and the regional attributes of grapes and wine. Full article

Current research does not fully elucidate the key compounds and their mechanisms that define the aroma profile of fresh jujube fruits. Therefore, this study conducted a comprehensive analysis of both free and glycosidically bound aroma compounds in fresh jujube fruits of ten cultivars. Utilizing gas chromatography–mass spectrometry (GC-MS), we identified 76 volatile free aroma compounds and 19 glycosidically bound volatile compounds, with esters, aldehydes, and ketones emerging as the predominant volatile compounds in the jujube fruits. Odor activity value (OAV) analysis revealed that the primary aroma profile of the jujubes is characterized by fruity and fatty odors, with β-damascenone being a key contributor to the fruity aroma, and (E)-2-oct-en-1-al and nonanal significantly influencing the fatty aroma. Moreover, the integration of sensory evaluation and partial least squares regression (PLSR) analysis pinpointed octanal, (E)-2-oct-en-1-al, nonanal, β-damascenone, and pentanal as significant contributors to the jujube’s characteristic aroma, while isoamyl acetate was identified as significantly influencing the fatty acid taste. This study not only underscores the complexity of the jujube aroma composition but also highlights the impact of environmental factors on aroma profiles, offering valuable insights into the sensory characteristics of jujube fruits. Full article

The species Prunus mume consists of uniquely aromatic woody perennials with large amounts of free aromatic substances in the flower cells. Uridine diphosphate glycosyltransferase (UGT) modifies these free aromatic substances into water-soluble glycoside-bound volatiles (GBVs) which play an important role in regulating the use of volatiles by plants for information exchange, defense, and stress tolerance. To investigate the changes in the glycosidic state of aromatic substances during the flowering period of P. mume and discern the location and expression of glycoside synthesis genes, we extracted and enzymatically hydrolyzed GBVs of P. mume and then utilized gas chromatography–mass spectrometry (GC–MS) to characterize and analyze the types and contents of GBV glycosides. Further, we identified and classified the members of the UGT gene family of P. mume using the bioinformatic method and analyzed the correlation between the expression of the UGT family genes in P. mume and the changes in glycosidic content. The results showed that the benzenoids were the main aromatic substance that was glycosylated during flowering in P. mume and that glycosidic benzaldehyde was the most prevalent compound in different flower parts and at different flowering stages. The titer of glycoside benzaldehyde gradually increased during the bud stage and reached the highest level at the big bud stage (999.6 μg·g⁻¹). Significantly, titers of glycoside benzaldehyde significantly decreased and stabilized after flowering while the level of free benzaldehyde, in contrast, significantly increased and then reached a plateau after the flowering process was completed. A total of 155 UGT family genes were identified in the P. mume genome, which were divided into 13 subfamilies (A–E, G–N); according to the classification of Arabidopsis thaliana UGT gene subfamilies, the L subfamily contains 17 genes. The transcriptome analysis showed that PmUGTL9 and PmUGTL13 were highly expressed in the bud stage and were strongly correlated with the content of the glycosidic form of benzaldehyde at all stages of flowering. This study provides a theoretical basis to elucidate the function of UGT family genes in P. mume during flower development, to explore the mechanism of the storage and transportation of aromatic compounds in flower tissues, and to exploit industrial applications of aromatic products from P. mume. Full article

To investigate the effects of the application of bentonite, tannins, and their combination in alcoholic fermentation, Malvazija istarska (Vitis vinifera L.) white grape must was treated with 95 g/L of bentonite, 25 g/L of a hydrolysable tannin preparation, while the third treatment received the aforementioned doses of both agents. Control grape must was fermented without bentonite and exogenous tannins. All of the produced wines were additionally fined after fermentation with doses of bentonite needed to achieve complete protein stability. Wines were analyzed both after fermentation and after additional bentonite fining. Standard physicochemical parameters were determined by the OIV methods, and phenols were analyzed by high-performance liquid chromatography with diode-array detection (HPLC-DAD), while the concentrations of free and bound volatile aroma compounds were obtained after solid-phase extraction (SPE) followed by gas chromatography–mass spectrometry (GC-MS). Bentonite and tannins in fermentation generally reduced the total dose of bentonite needed for complete stabilization. Treatments with bentonite slightly decreased the concentration of total dry extract, while tannins preserved total acidity. The negative effect of bentonite on flavonoids was more severe. Tannins in fermentation preserved more hydroxycinnamoyltartaric acids with respect to control wine, and this effect was additionally enhanced by bentonite. Volatile and bound aroma composition was affected by all the treatments, while the addition of tannins resulted in higher concentrations of several important odoriferous esters, such as ethyl hexanoate, ethyl decanoate, and hexyl acetate. Additional fining with bentonite to complete protein stabilization annulled some of the positive effects observed after fermentation. Full article

Leaf removal is a cultural practice mainly aimed at improving cluster zone microclimates and impacting primary and secondary metabolites, such as volatiles. This research aimed to assess the impact of defoliation on free and glycosylated aromas of a neutral (‘Nebbiolo’) and a semi-aromatic (‘Aleatico’) red variety. Defoliation was performed at fruit set (BBCH 71) and, for ‘Nebbiolo’, also at berries touch (BBCH 81) phenological stages. Skins and pulps were separately analyzed by Solid Phase Extraction–Gas Chromatography/Mass Spectrometry. Results showed that the response to defoliation was variety-dependent. For ‘Nebbiolo’, especially when performed at the berries’ touch stage, defoliation had a significant effect on the accumulation of free volatiles and glycosidic precursors. Differently, free and bound ‘Aleatico’ volatiles were less impacted by defoliation. Interestingly, in both grapevine varieties, defoliation significantly enhanced the accumulation of aroma precursors in grapes’ skins, which is of particular relevance for red wine production and their aging potential. Moreover, results could be helpful for the management of grape quality, as defoliation is currently considered as a strategy to address climate change issues. Full article

Sirex nitobei is an important wood-boring wasp to conifers native to Asia, causing considerable economic and ecological damage. However, the current control means cannot achieve better efficiency, and it is expected to clarify the molecular mechanism of protein–ligand binding for effective pest control. This study analyzed the expression pattern of CSP2 in S. nitobei (SnitCSP2) and its features of binding to the screened ligands using molecular docking and dynamic simulations. The results showed that SnitCSP2 was significantly expressed in female antennae. Molecular docking and dynamic simulations revealed that SnitCSP2 bound better to the host plant volatile (+)-α-pinene and symbiotic fungal volatiles terpene and (−)-globulol than other target ligands. By the molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) method, the free binding energies of the three complexes were calculated as −44.813 ± 0.189 kJ/mol, −50.446 ± 0.396 kJ/mol, and −56.418 ± 0.368 kJ/mol, and the van der Waals energy was found to contribute significantly to the stability of the complexes. Some key amino acid residues were also identified: VAL13, GLY14, LYS61, MET65, and LYS68 were important for the stable binding of (+)-α-pinene by SnitCSP2, while for terpenes, ILE16, ALA25, TYR26, CYS29, GLU39, THR37, and GLY40 were vital for a stable binding system. We identified three potential ligands and analyzed the interaction patterns of the proteins with them to provide a favorable molecular basis for regulating insect behavioral interactions and developing new pest control strategies. Full article

The peel and core discarded from the processing of MD2 pineapple have the potential to be valorized. This study evaluated the functional and volatile compounds in the extracts of MD pineapple peel and core (MD2-PPC). The total soluble solids, pH, titratable acidity, sweetness index, and astringency index were 9.34 °Brix, 4.00, 0.74%, 12.84, and 0.08, respectively, for the peel and 12.00 °Brix, 3.96, 0.32%, 37.66, and 0.03, respectively, for the core. The fat and protein contents of the peel and core were found to be significantly different (p < 0.05). The total phenolic (TPC) and flavonoid contents (TFC) were significantly higher in the peel. The peel also showed better antioxidant activity, with a half-maximal inhibitory concentration (IC₅₀) of 0.63 mg/mL for DPPH free radical activity compared with the core. The TPC of different phenolic fractions from peel extract was highest in the glycosylated fraction, followed by the esterified, insoluble-bound, and free phenolic fractions. GC–MS analysis identified 38 compounds in the peel and 23 in the core. The primary volatile compounds were 2-furan carboxaldehyde, 5-(hydroxymethyl), and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP). The identification of phenolics and volatile compounds provides important insights into the valorization of (MD2-PPC) waste. Full article

The importance of white wines in the northwest of the Iberian Peninsula has led to study on the aromatic profiles of 20 white grapevine varieties along three consecutive vintages. Volatile compounds were evaluated through solid-phase microextraction and gas chromatography-mass spectrometry methodology (SPME-GC-MS). The main aims of this study were as follow: test if their aromatic profile could be used as a potential chemotaxonomic tool to differentiate among grapevine varieties, evaluate if there is any relationship among the aromatic characteristics and the genetic origin of the varieties studied and try to bring out aromatically interesting varieties that could trigger diversified wine production in the study area. Free and bound volatile profiles were tentatively identified in each variety, grouping all identified compounds into thirteen volatile families to allow for a better discussion of the results obtained. Significant differences were found for terpenes among varieties in the free fraction and for acids, aldehydes, terpenes and norisoprenoids in the glicosidically bound fraction. Good differentiation among varieties was achieved by free and glicosidically bound profiles in the principal component analysis (PCA), as well as some clustering of varieties belonging to the same genetic reconstructed populations (RPP). Varietal aromatic profiling could be expected to be a good chemotaxonomic tool. Full article

In this study, UPLC-MS/MS was used to study the effects of smoking duration and temperature on the formation of heterocyclic amines (HAs) in smoke-processed meat patties. Four kinds of free HAs—including F-7,8-DiMeIQx; F-MeAαC; F-Harman and F-Norharman—and six kinds of protein-bound HAs—including B-AαC; B-7,8-DiMeIQx; B-Glu-p-1; B-MeAαC; B-Harman and B-Norharman—were detected and quantified. Among the free HAs, we observed a 23-fold content increase (p < 0.05), from 0–4 h (at 0 h and 4 h they were 4.24 ng·g⁻¹ and 98.33 ng·g⁻¹, respectively), and the content of the free HAs decreased to 78.80 ng·g⁻¹, at 5 h. At the same time, the free HAs content increased from 53.52 ng·g⁻¹, at 50 °C, to 127.16 ng·g⁻¹, at 60 °C, and then decreased continuously. The content of the free HAs was the highest at 60 °C. For the protein-bound HAs, their content was found to generally decrease with the increase in smoking duration and temperature. However, at 5 h, the content of protein-bound HAs slightly increased to 984.2 ng·g⁻¹. Meanwhile, at 90 °C, it increased to 1643.53 ng·g⁻¹. Additionally, a total of 16 volatile organic compounds (VOCs) were found in all of the meat samples, of which 10 VOCs (one acid, three aldehydes and seven phenols) were significantly related to the formation of free HAs. These findings showed that all the different types of HAs were produced under low-temperature processing, which provided scientific insights into the potential generation of HAs during meat smoking processes and could be used as a reference to minimize the risks of cancer related to the consumption of smoked meat products. Full article

Aldehydes, particularly acetaldehyde, are carcinogenic molecules and their concentrations in foodstuffs should be controlled to avoid upper aerodigestive tract (UADT) and liver cancers. Highly reactive, acetaldehyde forms DNA and protein adducts, impairing physiological functions and leading to the development of pathological conditions. The consumption of aged beer, outside of the ethanol metabolism, exposes habitual drinkers to this carcinogen, whose concentrations can be over-increased due to post-brewing chemical and biochemical reactions. Storage-related changes are a challenge faced by the brewing industry, impacting volatile compound formation and triggering flavor instability. Aldehydes are among the volatile compounds formed during beer aging, recognized as off-flavor compounds. To track and understand aldehyde formation through multiple pathways during beer storage, consequent changes in flavor but particularly quality losses and harmful compound formation, this systematic review reunited data on volatile compound profiles through gas chromatography analyses from 2011 to 2021. Conditions to avoid flavor instability and successful methods for reducing beer staling, and consequent acetaldehyde accumulation, were raised by exploring the dynamic conversion between free and bound-state aldehydes. Future research should focus on implementing sensory analyses to investigate whether adding aldehyde-binding agents, e.g., cysteine and bisulfite, would contribute to consumer acceptance, restore beer flavor, and minimize acetaldehyde-related health damage. Full article