Search Results (806)

The impact of seasonality on the aroma quality of tea has been documented in various tea types, but not specifically in oolong tea. This study is the first to explore the complex relationships between seasonality, volatile compounds, and aroma quality in oolong tea. Using Headspace Solid-Phase Microextraction Gas Chromatography–Mass Spectrometry (HS-SPME-GC-MS)-based untargeted metabolomics, we analyzed 266 samples of Tieguanyin oolong tea. The data identified linalool, linalool oxides (trans-linalool oxide (furanoid) and trans-linalool oxide (pyranoid)), and their metabolites (diendiol I; hotrienol) as key seasonal discriminants. Four out of the top ten key differential compounds for distinguishing aroma scores were metabolites from fatty acid degradation, namely trans-3-hexenyl butyrate, trans-2-hexenyl hexanoate, hexyl hexanoate, and hexyl 2-methyl butyrate. Approximately one-fifth of the seasonal discriminant volatile compounds were significant in influencing aroma quality. Overall, the impact of seasonality on the aroma quality of finished Tieguanyin oolong tea is marginal. These findings enhance our understanding of the interplay between seasonal variations, volatile composition, and aroma quality in oolong tea. Full article

During red wine production, managing the pomace cap is key for a successful fermentation, allowing the extraction of phenolics and other metabolites and providing the necessary oxygen for yeast activity. In recent years, automatic cap management systems based on the injection of gases have gained popularity, despite the limited scientific information regarding the outcomes of their use. This trial aimed to evaluate the composition of wine during industrial red wine fermentations using an automatic sequential air injection system (i.e., AirMixing MI^TM). Fourteen lots of Cabernet Sauvignon grapes were fermented using four air injection regimes, where the intensity and daily frequency of air injections were set to either low or high. As expected, the treatment combining high-intensity and high-frequency air injection produced the largest dissolved oxygen peaks reaching up to 1.9 mg L⁻¹ per cycle, compared to 0.1 mg L⁻¹ in the low-intensity and low-frequency treatment. Yet, in all cases, little to no accumulation of oxygen overtime was observed. Regarding phenolics, the highest intensity and frequency of air injections led to the fastest increase in total phenolics, anthocyanins, short polymeric pigments, and tannin concentration, although compositional differences among treatments equilibrate by the end of fermentation. The main differences in phenolic compounds observed during fermentation were mediated by temperature variation among wine tanks. Based on these findings, it is advisable to keep the characterizing kinetics of phenolic extraction and expand the study to the aroma evolution of wines fermented with this technology. Full article

Rootstocks are widely used in viticulture as an agronomic measure to cope with biotic and abiotic stresses. In winegrapes, the aroma is one of the major factors defining the quality of grape berries and wines. In the present work, the grape aroma and wine aroma of Cabernet Sauvignon (CS) grafted on three rootstocks were investigated to inform the selection of rootstocks to utilize. 1103P, 5A, and SO₄ altered the composition of aromatic volatiles in CS grapes and wines. Among them, 5A and SO₄ had less effect on green leaf volatiles in the berries and wines, while 1103P increased green leaf volatile concentrations, up-regulating VvADH2 expression in both vintages. VvLOXA, VvLOXC, VvHPL1, VvADH1, VvADH2, and VvAAT were co-regulated by vintage and rootstock. Orthogonal partial least squares regression analysis (OPLS-DA) showed that the differential compounds in CS/1103P and CS berries were dominated by green leaf volatiles. Furthermore, the concentrations of 1-hexanol in the CS/1103P wines were significantly higher than in the other treatments in the two vintages. 1103P altered the expression of genes in the LOX-HPL pathway and increased the concentration of grape green leaf volatiles such as 1-hexanol and 1-hexanal, while vine vigor also affected green leaf volatile concentrations, the combination of which altered the aromatic composition of the wine and gave it more green flavors. Full article

In this study, whole grain sorghum flour was used to partially substitute the gluten-free flour blend in cookie formulation at 20% (C20) and 40% (C40) replacement levels. The goal was to explore its potential to improve the nutritional value and sensory appeal of cookies relative to conventional and commercially available gluten-free alternatives. Nutritional analysis revealed that cookies with added sorghum flour showed increased levels of protein, ash, and polyphenolic compounds, while maintaining favorable macronutrient profiles. Notably, several bioactive compounds, such as gallic acid, caffeic acid, and apigenin, were detected exclusively in sorghum-containing samples, suggesting enhanced functional properties. Despite these compositional changes, textural measurements showed no significant differences in hardness or fracturability compared with the control. Sensory profiling using the Rate-All-That-Apply (RATA) method demonstrated that both samples (C20 and C40) achieved balanced results in terms of aroma as well as texture and were generally well accepted by the panel. The results indicate that moderate inclusion of sorghum flour (20% and 40%) can improve the sensory and nutritional profiles of gluten-free cookies without compromising product acceptability. Sorghum thus offers a promising pathway for the development of high-quality, health-oriented, gluten-free bakery products. Full article

This study investigated the effects of six cap management protocols targeting contrasting oxidation-reduction potential (ORP) evolutions during alcoholic fermentation of Pinot noir wines. Treatments included twice-daily punch-downs (PD) and pump-overs (PO), 1 h air or N₂ injections (AirMix, N₂Mix), air injections triggered by ORP ≤ −40 mV (RedoxConAir), and equal N₂ injections concurrent to RedoxConAir wines (RedoxConN₂). AirMix wines maintained ORP values above 0 mV throughout fermentation, showed an oxidatively favored glutathione-to-glutathione disulfide ratio (GSH:GSSG) of 0.3:1, and had 21% lower total phenolics and 24% lower anthocyanins than PD wines. In contrast, N₂Mix wines maintained the lowest ORP, near −100 mV, and showed a reductively favored GSH:GSSG ratio (7:1). PD wines extracted 48% more flavan-3-ols than PO wines, consistent with greater berry integrity disruption and seed submersion. Volatile composition was also impacted: ethyl n-octanoate showed the highest OAV among esters, ranging from 147 in PO wines to 116 in AirMix wines. Results suggest the GSH:GSSG ratio served as an indicator of redox history, with potential implications for color and aroma preservation during aging. Inert gas mixings resulted in equal or greater total phenolic content, while excessive air injections may provide a tool to soften astringency. Full article

Flavor, as one of the primary factors that attracts consumers, has always been a crucial indicator for evaluating the quality of food. From processing to final consumption, the conditions that affect consumers’ perception of the aroma of aquatic products can be divided into three stages: aroma formation, release, and signal transmission. Currently, there are few reviews on the formation, release, and perception of aroma in aquatic products, which has affected the product development of aquatic products. This review summarizes aroma formation pathways, the effects of processing methods, characteristic volatile compounds, various identification techniques, aroma-release influencing factors, and the aroma perception mechanisms of aquatic products. The Maillard reaction and lipid oxidation are the main pathways for the formation of aromas in aquatic products. The extraction, identification, and quantitative analysis of volatile compounds reveal the odor changes in aquatic products. The composition of aquatic products and oral processing mainly influence the release of odorants. The characteristic odorants perceived from the nasal cavity should be given more attention. Moreover, the relationship between various olfactory receptors (ORs) and the composition of multiple aromatic compounds remains to be understood. It is necessary to clarify the relationship between nasal cavity metabolism and odor perception, reveal the binding and activation mode of ORs and odor molecules, and establish an accurate aroma prediction model. Full article

Following hygiene standards in milk production is essential for making high-quality sour cream, especially when using traditional methods that rely on raw milk. The aim of this study was to determine the physicochemical, microbiological, and sensory quality of artisanal sour cream samples collected from major marketplaces in the wider Zagreb area. On average, the samples contained 27.99% milk fat, 3.30% protein, 34.29% dry matter, 6.51% fat-free dry matter and 3.00% lactose, with considerable variability observed across all components. Microbiological analysis revealed the presence of Staphylococcus aureus in 35.30% of the samples, Enterobacteriaceae in 76.47%, Escherichia coli in 94.11%, Bacillus spp. in 23.53%, and yeasts in 100% of the samples. Listeria monocytogenes and Salmonella spp. were not detected. The sensory analysis of the textural properties showed significant variability in firmness, adhesiveness, viscosity, creaminess, and fizziness. Samples with higher milk fat and dry matter content were rated better for creaminess, viscosity and mouth firmness. Flavour assessments, particularly for cream and diacetyl notes, also varied widely among samples. These findings highlight the complexity of sour cream’s sensory attributes and the significant influence of ingredient composition and processing techniques on appearance, aroma, texture, taste, and flavour. Principal component analysis (PCA) with Varimax rotation simplified the data structure and identified key dimensions of quality variation. Principal component analysis (PCA) revealed that the first principal component (PC1) effectively discriminated the cream samples based on sensory attractiveness and indicators of spoilage and highlighted the association between off-flavour and microbial contamination with inferior characteristics. The second principal component (PC2) captured the differences in physicochemical characteristics and showed a gradient from richer, creamier samples with higher fat content to those with lower acidity and higher freshness. Full article

This study aimed to develop a fermented mango-based beverage using Lactiplantibacillus plantarum strains Lp6 and Lp32, focusing on enhancing its functional properties, ensuring microbiological safety, improving nutritional value, and achieving sensory acceptability. A central composite design (CCD) was employed to assess the effects of two factors (fermentation time and inoculum concentration) on several response variables: viable cell concentration (CC), total phenolic compounds (TPCs), total flavonoid compounds (TFCs), and concentrations of L-lactic acid and D-lactic acid. The optimized formulation was achieved using L. plantarum Lp6, with an inoculum concentration of 9.89 Log (7.76 × 10⁹) CFU/mL and a fermentation time of 20.47 h. Under these conditions, the beverage reached the highest values for CC, TPC, TF, and L-lactic acid while minimizing the production of D-lactic acid. Following optimization, the fermented beverage underwent further characterization, including physicochemical analysis, microbiological evaluation, proximate composition analysis, and sensory evaluation. The final product exhibited a viable cell count of 13.01 Log (10.23 × 10¹²) CFU/mL, demonstrated functional potential, complied with microbiological safety standards, and showed adequate nutritional content. Sensory analysis revealed high consumer acceptability, attributed to its distinctive mango aroma and flavor. These findings highlight the potential of this fermented mango-based beverage as a novel functional food with promising market appeal. Full article

The art of food–drink pairing has always fascinated gourmets and cooking enthusiasts. While wine has long held pride of place on the table, natural mineral water plays a central role in this new concept. Through the Pyramid of Natural Mineral Waters, we aim to explore the relationships between the structure of water and food, flavors and aromas, revealing a world of previously unexplored nuances and tastes. This new approach is based on the analysis of the fixed residue of water, i.e., the amount of mineral salts dissolved in it. The fixed residue gives the water unique organoleptic characteristics, influencing the perception of flavors and sensations in the mouth. By analyzing the technical data sheet of mineral waters designed by us, it is possible to identify their main characteristics and combine them in a consistent way with various dishes, as proposed in the pyramid scheme. There are many possible combinations between natural mineral waters and foods, depending on numerous factors, including the type of water and the salts dissolved in it, the type of food, the cooking method, and the types of sauces and condiments present in the dish. To guide consumers in this fascinating universe, the figure of the water sommelier, or so-called hydro-sommelier, was born. As expert connoisseurs of natural mineral waters, they are able to recommend the ideal water for every occasion, maximizing the taste characteristics of the food served at the table. This study is completed with the construction of the Pyramid of Natural Mineral Waters, which relates the composition of water, specifically the salient characteristics related to dissolved minerals, with the respective food combinations recommended by us, in relation to the structure of both water and food. Full article

The aim of this study was to investigate the effects of the crop load on the berry and wine composition of Marselan grapes. Thus, the appropriate crop load for Marselan wine grapes in Ningxia was determined based on the shoot density and the number of clusters per shoot. Marselan grapes from the Gezi Mountain vineyard, located at the eastern foot of Helan Mountain in the Qingtongxia region of Ningxia, were selected as the research material to conduct a combination experiment with four levels of shoot density and three levels of cluster density. The analysis of the berry and wine chemical composition was combined with a wine sensory evaluation to determine the optimal crop load levels. Crop load regulation significantly affected both the grape berry composition and the basic physicochemical properties of the resulting wine. Low crop loads improved metrics such as the berry weight and soluble solids content. A low shoot density facilitated the accumulation of organic acids, flavonols, and hydroxybenzoic acids in wine. Moderate crop loads were conducive to anthocyanin synthesis—the total individual anthocyanins content in the 10–20 shoots per meter of the canopy treatment group ranged from 116% to 490% of the control group—whereas excessive crop loads hindered its accumulation. Crop load management significantly influenced the aroma composition of wine by regulating the content of sugars, nitrogen sources, and organic acids in grape berries, thereby promoting the synthesis of esters and the accumulation of key aromatic compounds, such as terpenes. This process optimized pleasant flavors, including fruity and floral aromas. In contrast, wines from the high crop load and control treatments contained lower levels of these aroma compounds. Compounds such as ethyl caprylate and β-damascenone were identified as potential quality markers. Overall, the wine produced from vines with a crop load of 30 clusters (15 shoots per meter of canopy, 2 clusters per shoot) received the highest sensory scores. Appropriate crop load management is therefore critical to improving the chemical composition of Marselan wine. Full article

Bingdao ancient tree tea (BATT), a type of raw Pu-erh tea, is renowned for its brewing durability, characterized by a unique aroma and flavor. To explore the dynamic changes in infusion quality and the impact of multiple steeping process, BATT was brewed 14 times, and its sensory attributes, infusion color, and chemical composition were assessed across different brewing intervals. The color of the tea infusion remained relatively stable throughout the brewing process. Sensory evaluation indicated that BATT exhibited optimal sensory quality between the third and seventh infusions. While the leaching of polyphenols showed minimal variation across brews, the concentrations of ester-catechins, non-ester catechins, free amino acids, and caffeine after the seventh brewing decreased by 28.82%, 21.83%, 28.86%, and 40.37%, respectively. Our results indicated that higher concentrations of flavor compounds in the BATT infusion appeared between the fourth and seventh brews. This study provides a theoretical basis for understanding the brewing characteristics of BATT. Full article

Aroma is an important indicator for evaluating the quality of baijiu. In this study, we determined the aroma-active compounds in four representative brands of strong-aroma baijiu from Sichuan and Jianghuai regions through GC-MS/O, and GC-TOF-MS quantification. In addition, the non-volatile composition of four baijiu samples was quantified by BSTFA derivatization and GC-MS. By constructing a full recombination model containing both volatile and non-volatile components, the effect of different groups of non-volatile compounds on the aroma of strong-aroma baijiu was evaluated through recombination-omission tests. A total of 72 aroma-active compounds and 59 non-volatile compounds were identified and quantified. The results indicated that pyrazines, furfural, and furan derivatives displayed higher aroma intensities in strong-aroma baijiu produced in Sichuan compared to that produced in Jianghuai. The recombination model that included both aroma-active and non-volatile compounds showed a closer resemblance to the original baijiu samples, underscoring the critical role these compounds play in shaping the dominant aroma profile of strong-aroma baijiu. Non-volatile compounds significantly influenced six aroma attributes: fruity, sweet, sauce, pit, acidic, and alcoholic notes. Omission tests revealed that among posorly volatile organic acids, monobasic acids had distinct effects on the aroma profile, while dibasic acids did not show any noticeable influence on the sensory characteristics. Full article

In this study, gravlax, a niche Scandinavian delicacy, was comprehensively investigated by producing it with combinations of two different fish species (tub gurnard (Chelidonichthys lucerna Linnaeus, 1758) and garfish (Belone belone Linnaeus, 1761)) and five herbs (dill (Anethum graveolens Linnaeus, 1753), sage (Salvia officinalis Linnaeus, 1753), mint (Mentha piperita Linnaeus, 1753), sweet (Ocimum basilicum Linnaeus, 1754), and purple basil (Ocimum basilicum var. purpurascens Bentham, 1830)). The nutritional composition, amino acids, color parameters, mineral substances, and heavy metal content, as well as physical characteristics, texture profile analysis, and extensive sensory analyses, were conducted, and the results were thoroughly evaluated using multivariate statistical methods. The influence of using different herbs on nutritional composition was found to be significant in gravlax made from both fish species (p < 0.05). Sensory analyses revealed that panelists identified mint as enhancing aroma and umami sensations, while dill improved overall acceptance. Gravlax with sage exhibited softer textures, but lower general acceptance due to perceived high saltiness. Color analyses revealed that purple basil transferred distinct pigments, causing darkening, whereas sweet basil had a brightening effect. Amino acid analyses revealed higher umami and sweet-tasting amino acids in herb-free gravlax, whereas proteolytic activity appeared to slow down in herb-containing gravlax samples. Full article

Citrus fruit are well-known for their characteristic flavour and nutritional value. Global citrus production has increased by 528% between 1961 and 2021, and in Australia, citrus is the most exported fresh fruit product by volume. There are six described Citrus species endemic to Australia: C. australasica (Australian finger lime), C. australis (round lime), C. garrawayi (Mount White lime), C. glauca (desert lime), C. gracilis (Humpty Doo lime), and C. inodora (Russell River lime). Australian Citrus possess unique flavours, aromas, and phytochemical profiles, suggesting a potential use as novelty crops and/or ‘functional foods’. Furthermore, the native Australian Citrus germplasm is a valuable source of desirable traits in citrus breeding, including drought, cold, heat, salinity, and disease resistance. These may help solve some challenges facing citrus growers globally, including disease, a declining soil quality, changing climates, and narrowing profit margins. However, many Australian citrus species’ nutritional value, chemical composition, and bioactive properties remain unknown. This review focuses on these under-investigated native Citrus species, their distribution, production, physiology, disease tolerance, traditional use, taxonomy, flavour, nutritional composition, bioactivity, and commercial production. It concludes with a perspective on the future of these native species in the Australian and global citrus context. Full article

Hops (Humulus lupulus L.) are a critical component in beer brewing. The growing demand for craft beer has increased interest in hop cultivation in non-traditional regions where unfavorable climatic conditions hinder optimal yield and quality. To address these challenges, this study investigates the effects of plant growth regulators (PGRs) on hop cone yield and chemical compositions. In two separate studies, year-1 Cascade hops were subjected to various PGR treatments in the field. PGR treatments generally had minimal effect on the dry cone yield in study I. In study II, a combination of Ethephon at 45 mg/L and ProGibb at 3 mg/L significantly increased the cone yield by 125% compared to the control. While all treatments had a “good quality” hop storage index, a combination of Ethephon and ProGibb produced alpha acid percentages within the commercial standard range. Ethephon at 30 mg/L combined with ProGibb at 2 mg/L enhanced bitterness and aroma, delivering the highest concentration of volatile organic compounds at 569.7 mg/L, thereby enhancing aroma compounds associated with fruity esters, monoterpenes, and sesquiterpenes. This study demonstrates that specific PGR treatments can improve the chemical composition of hops grown in non-traditional regions, with implications for optimizing aroma and bitterness in beer. Full article