Volatile Profile Research Articles

Aroma enhancement of dealcoholized wines using enzyme treatment and glycosidic aroma precursors

This research has studied the treatment of dealcoholized wines with glycosidic enzymatic preparation and glycosidic aroma precursors extract isolated from aromatic grapes in order to enhance the aroma profile of non-alcoholic white wines. The effect of the addition of the precursors extract and the enzymatic treatment was studied after 15 and 30 d of storage, using dealcoholized wine as control. The analysis of free and bound volatile compounds was carried out by gas chromatography-mass spectrometry (GC-MS) after isolation using solid-phase extraction (SPE). The application of multivariate statistical analysis confirmed differences in the free and bound volatile profile of the studied samples when applicated the different treatments after 15 d and 30 d of storage. The combination of both treatments increased in a significant way the aromatic profile of Verdejo dealcoholized wine, showing high concentrations of terpenic and bencenic compounds due to the addition of precursors extract from an aromatic grape variety. This brings to light that this technique could be considered as a possible way of enhancing the aroma profile of dealcoholized wines in La Mancha region, as well as a way of using by-products from the wine industry, thus contributing to the concept of circular economy.

Bee bread boosts probiotic Yoghurt: Unveiling the impact on physiochemical, microbiological, and sensory attributes

This study aimed to investigate the effects of bee bread ratios of 0.5%, 1%, and 2%, respectively on some parameters in probiotic yoghurt production. The bee bread composition contained the elements B, Ca, Fe, K, Mg, Na, P, and Zn. The analysis of sugar composition revealed the presence of fructose, glucose, and sucrose. The organic acid and phenolic substance content were assessed. The following values were obtained: oxalic acid (1.26 mg/g), malic acid (7.79 mg/g), ascorbic acid (0.91 mg/g), citric acid (2.73 mg/g), p-coumaric acid (15.3 µg/g) and kaempferol (5.562.4 µg/g). The study determined the tocopherol content, specifically alpha (7.09 µg/g), beta (0.4 µg/g), gamma (0.77 µg/g), and delta (0.31 µg/g). A total of 55 distinct components were identified while analyzing the volatile and aroma profiles. This study found that the IC50 value of bee bread was 1.414 mg/mL. Bee bread did not affect physicochemical parameters such as pH, acidity, dry matter, ash, milk fat, and water holding capacity (P>0.05) but affected protein and syneresis (P<0.05). The addition of bee bread positively affected Streptococcus thermophilus and Lactobacillus bulgaricus, and Lactobacillus acidophilus LA-5 activity was preserved at around 107 kob/g during storage (P<0.05). Adding bee bread affected the color parameters L*, a*, and b* values (P<0.05). Consumers preferred the group to which 0.5% bee bread was offered following sensory analytical evaluation. The study has demonstrated that adding bee bread during yoghurt production can effectively maintain probiotic activity.

Characterization of the Geographical Origin of the Traditional Chinese Fermented Soybean Douchi by Gas Chromatography-Mass Spectrometry (GC-MS) and Chemometrics

Douchi is a highly appreciated product due to its unique flavor, high nutritional value, and health benefits. Douchi from different regions exhibits distinct characteristics. The objective of this study was to investigate the volatile profiles in douchi produced from different geographical origins using gas chromatography-mass spectrometry (GC-MS) and chemometrics. The volatiles were extracted by headspace solid-phase micro-extraction (HS-SPME) and subsequently determined by GC-MS. A comparative analysis was further conducted to identify the variations in volatile compounds among the samples. The correlation between the samples was investigated by employing cluster analysis (CA) and principal component analysis (PCA). An orthogonal partial least squares-discriminant analysis (OPLS-DA) model was established to discriminate samples from different regions and identify key differential compounds. A total of 46 volatile compounds were detected, among which terpenes, alcohols were the main compounds. Furthermore, 14 key differentiating compounds were screened out based on the OPLS-DA modle. The application of GC-MS combined with chemometrics offers a theoretical framework for douchi quality control and classification.

Modulating fine flavor cocoa attributes: Impact of seed-to-bean transformation under controlled conditions on metabolite, volatile and sensory profiles

Fine-flavored chocolates are distinguished by their complex and distinct flavor profiles, which includes notes such as floral, fruity, nutty, and spicy. This study sought to modulate the flavor development of chocolates by establishing controlled processing conditions during the transformation from seed to bean in a laboratory setting, to produce superior quality chocolates. Our experimental setup comprised two varying temperature levels (30 °C and 45 °C) and three organic acids (OAs: acetic, lactic, and citric acids) at concentrations of 1–30 g/L to adjust the pH of the transformation system. Our study focused on how these conditions affect the development of distinct flavor profiles in chocolate bars, emphasizing the enhancement of fine-flavor notes. Flavor development was monitored through the untargeted metabolomics of cocoa beans and analyzing the volatile compounds and sensory profiles of the resultant chocolates. This study revealed that OA concentration markedly influenced metabolite formation, particularly affecting peptides, volatile organic compounds, and flavor notes. Chocolates derived from seeds processed with 30 g/L acid solutions demonstrated enhanced fruitiness and acidity, whereas those processed with 1 g/L acid solutions exhibited pronounced nuttiness and cocoa taste attributes but lower acidity. These findings underscore the significance of meticulously managing flavor development processes to produce fine-flavored chocolates with unique aromatic profiles. Crucially, variables in the controlling process, such as temperature and pH, are essential for fine-tuning flavor attributes, enabling the correlation and identification of key quality biomarkers to elucidate flavor development pathways.

The use of microencapsulated banana flower powder pellet on in vitro ruminal fermentation, digestibility, microbial diversity, and methane production.

Ruminant animals constitute major contributors to greenhouse gas (GHG) emissions and play an important part in sustainable agricultural systems. A bioactive compound (BC) with antibacterial properties was utilized to inhibit rumen methanogens and decrease ruminant methane emissions. The bio efficacy of ruminant nutrition was frequently employed using a new technology through microencapsulation technique to produce stable products. The microencapsulated banana flower powder pellet (mBAFLOP) powder was used as a BC in the diets. Consequently, this study aimed to evaluate the effects of mBAFLOP supplementation on in vitro gas production kinetics, rumen fermentation, microbial population, and methane production. A completely randomized design (CRD) was used to randomly assign respective treatments at 0, 1, 2, and 3% of the total dry matter (DM) substrate. Ruminal pH, in vitro dry matter degradability and volatile fatty acid profile both at 12, and 24h were not negatively affected by supplementation with mBAFLOP. The supplemented mBAFLOP (3% of total DM substrate) resulting in ruminal ammonia-nitrogen concentrations was linearly increased (P < 0.01) different among treatments, while methane production was reduced when compared with other treatment (quadratic effect, P < 0.05). Moreover, Ruminococcus flavefaciens was increased when the proportion of mBAFLOP supplement was increased. Furthermore, there was a linear effect (P < 0.05) of decreasing Methanobacteriales in the rumen with increased levels of mBAFLOP supplementation. Based on this study, the use of mBAFLOP at 3% could enhance NH3N concentration and cellulolytic bacteria especially Ruminococcus flavefaciens was increased. Furthermore, supplementation with mBAFLOP decreased methane production. Therefore, a possible dietary plant-based bioactive compound, mBAFLOP supplementation cloud enhances rumen fermentation and mitigates methane production.

Biochemical and physicochemical characteristics and volatile profiles of Erzincan Tulum cheese coagulated by herb-fortified artisanal lamb rennet

The characteristics of Erzincan Tulum cheese (ETC), an artisanal ewe-milk cheese and the first cheese with the designation of origin in Türkiye, are closely related to the geographical location of production and the human factors influencing every stage of the production process. This study aims to determine the influence of different coagulants (namely, herb-fortified artisanal lamb rennet (ALR), artisanal calf rennet (ACR), and commercial calf rennet (CCR)) on the biochemical, physicochemical characteristics, and volatile compounds of ETC, produced on the Heybeli plateau of the Erzincan province. Using artisanal rennet increased total solids, fat content, and acidity while decreasing pH and aw values. The highest PTA-SN (soluble nitrogen in 5 % phosphotungstic acid, w/v) and TCA-SN (soluble nitrogen in 12 % trichloroacetic acid w/w) values at the end of the ripening period (day 150 of storage) were observed in the ALR-Cheese (ALR-C). Furthermore, this cheese exhibited the highest rate of lipolysis (P < 0.01). Electrophoretograms revealed that αs-1 and β-casein degradation rates were the most significant in ALR-C. Following the 30th day of storage, the highest counts of lactic acid bacteria (LAB) were found in ALR-C. The most rapid reduction of coliforms, E. coli, and yeast-mold was observed in this sample throughout the storage. Eighty-nine volatile compounds were identified in the samples. Particularly noteworthy, ALR-C exhibited the highest ratios of hexanoic, octanoic, and decanoic acids after 90 days of storage. Additionally, steroid compounds were exclusively detected in this sample. The findings of this research make a substantial contribution to the existing literature concerning rennet types and the aromatic profile of ETC. These aspects are crucial for further investigations to enhance the cheese's quality and safety.

Association mapping analysis (AMA) for morpho-agronomic traits and leaf aromatic compounds using SSR markers in three types of Perilla crop collected from South Korea.

Perilla is a representative leafy vegetable in South Korea. As K-Food (Korean food) is in the spotlight around the world, there is also increasing interest in Western countries in Perilla crop, an annual plant belonging to the Lamiaceae family. To discover comprehensive information, including genetic and phylogenetic relationships among the 80 native Perilla accessions, using three types of data: simple sequence repeat (SSR) marker data, volatiles profile data, and morpho-agronomic data. This study conducted genotypic and phenotypic analyses on 80 Perilla accessions of three types (cultivated var. frutescens, weedy var. frutescens, weedy var. crispa) from South Korea. Five groups (G1-G5) of the 80 Perilla accessions of the three types were differentiated into two different clusters [genotype-based clustering (GTC) and phenotype-based clustering (PTC)] based on an aroma sensory phenotypic test. A total of 314 alleles were confirmed using 55 Perilla SSR primer sets, and genetic variation in the 80 Perilla accessions was evaluated. Among the three statistical analysis methods, principal coordinate analysis (PCoA) and GTC using data of the 55 Perilla SSR markers revealed perfectly consistent results, whereas PTC produced a total of six clusters. The 10 Perilla SSR markers associated with and significantly correlated with both biochemical and morphological characteristics were selected. These findings are expected to provide valuable information for developing global South Korean Perilla cultivars for further studies in Perilla crop breeding programs.

Characterization of volatile profiles and markers prediction of eleven popular edible boletes using SDE-GC–MS and FT-NIR combined with chemometric analysis

Wild edible boletes mushrooms are regarded as a delicacy in many countries and regions due to their rich nutritional contents and strong aromatic compounds. This study aimed to identify 445 samples of 11 boletes species collected from Yunnan and Sichuan provinces through molecular analysis. Using simultaneous distillation–extraction (SDE) combined with gas chromatography-mass spectrometry (GC–MS), 97 volatile compounds were identified. Chemometric methods were then applied to analyze the heterogeneity of these volatile compounds among the different species. The results showed that, 22 and 21 volatile compounds were selected using variable importance in projection (VIP > 1) and relative odor activity values (ROAV > 0.1), respectively. Partial least squares discrimnatint analysis (PLS-DA) was then employed to develop pattern recognition models for 11 species, which demonstrated strong identification performance. Furthermore, correlation heat maps, volcano plots, and Fisher linear discriminant analysis identified five volatile organic compounds, including methyl (9E)-9-octadecenoate, 2, 6-dimethylpyrazine, 1-decen-3-one, furfural, and methional as markers for distinguishing 11 boletes species. Ultimately, the rapid content prediction models of partial least squares regression (PLSR) were established by combining Fourier Transform Near-Infrared Spectroscopy (FT-NIR) with the concentrations of these five marker compounds. These findings provide a methodological strategy for the effective species identification of wild edible mushrooms and the rapid prediction of their characteristic aroma compounds.

Effect of refrigeration and reheating on the lipid oxidation and volatile compounds in silver carp surimi gels.

As unsaturated and saturated aldehydes, ketones are known to be responsible for off-odors in surimi products, and they are mainly derived from lipid oxidation. Because surimi-based products are rich in unsaturated fatty acids, they are prone to producing off-odors during the refrigeration and reheating processes, which are common treatments for leftovers. The present study investigated the color, lipid oxidation productions, fatty acid profiles and volatile components in surimi gels during refrigeration at 4 °C for 3 days with multiple reheating. The results revealed that the accumulation rate of hydroperoxides was higher in the refrigeration stage, whereas the decomposition rate was higher during reheating in surimi gels. Both refrigeration and reheating treatments promoted conjugated diene values, acid values and carbonyl values. Nevertheless, reheating treatment decreased tohiobarbituric acid reactive substances and whiteness. The contents of unsaturated fatty acids, especially α-linolenic acid, arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid, were reduced, whereas the contents of saturated fatty acids increased during refrigeration and multiple reheating. The unsaturated fatty acids were lost as a result of their oxidative deterioration. The volatile components profile showed that the accumulation of volatile components mainly occurred in the refrigeration stage. Multivariate data analysis was utilized to further clarify whether the off-odors in surimi gels were mainly generated in refrigeration. Refrigeration and reheating both contributed to lipid oxidation and the generation of volatile compounds in surimi gels, but the off-odors were mainly generated during refrigeration. This research provides a novel understanding of the formation of food odors in processing. © 2024 Society of Chemical Industry.

Volatile organic compound profile for the search of rejection markers in protein baits used as Vespa velutina control method

The invasive species Vespa velutina nigrithorax (Lepeletier 1836), commonly known as the Asian hornet, constitutes an economic and environmental threat, as it is a predator of fruits and insects, especially Apis mellifera (Linnaeus, 1758) (honey bees).Different methods have been developed for its control. Among of them, biocidal protein baits are included, which have a limited time of use. Oxidation of their components, enzymatic activity and microorganisms lead to the formation of spoilage compounds.The aim of this work was to determine the optimal conditions for storing and preserving the baits without losing efficacy. Furthermore, a search of rejection markers will be carried out based on field studies results in the apiary on the acceptance and rejection of the baits by hornets under different storage conditions.Volatile organic compound profiles of these baits were obtained by solid phase microextraction/gas chromatography/mass spectrometry (SPME-GC–MS). The data were processed using different statistical and chemometric tools.The identification of potential rejection markers belonging to the families of ketones, esters, alcohols and amines was carried out by partial least squares discriminant analysis (PLS-DA). The four markers with the highest VIP scores were 2-butanone, 2-heptanone, 1-butanol, 3-methyl and 1-butanol, 3-methyl, acetate.

Deciphering aroma complexity between melting flesh and stony hard peach (Prunus persica L.) fruit through integrative analysis of volatile contributions

Stony hard peach is favored in production for resistance to storage and transportation, but presents a challenge of lacking fragrance compared to traditional fragrant peach i.e., melting flesh peach. Addressing this concern necessitates material composition analysis from the perspective of volatile composition and aroma characteristics. However, the complex relationship between volatile compounds and aroma profiles in melting flesh and stony hard peach cultivars remains poorly understood. To address this gap, we examined contribution of volatiles to their aroma. The application of multiple analysis methods, including distribution, odor importance, and partial least squares discriminant analysis facilitated a comprehensive understanding of the contribution of 30 volatiles to aroma; and hierarchical clustering analysis revealed relationships among the compounds within the two types of peaches. The primary differential volatiles between them were cis-3-hexenol, pentyl acetate, prenyl acetate, trans-2-hexenal, cis-3-hexenyl acetate, dihydro-β-ionone, benzaldehyde, and a range of lactones (γ-decalactone, γ-hexalactone, γ-octalactone, δ-decalactone and γ-undecalactone). Overall, the melting flesh peach exhibited more pronounced aroma than the stony hard type. This study underscores the significance of understanding the intricate interplay between volatile compounds and aroma characteristics across cultivars with different textures, offering valuable insights into cultivar selection, flavor enhancement, and consumer preference assessment within the peach industry.

The advantages and trends of lactic acid fermentation in the production of innovative fruit puree: Analysis with PROMETHEE and cluster.

The goal of this study was to create a fermented probiotic fruit puree for lactose-intolerant people, vegetarians, and infants over 6 months old. Fermented fruit purees were developed using apples, peaches, and bananas with lactic acid bacteria (LAB) strains: Lactobacillus plantarum subsp. plantarum (S5), Lactobacillus fermentum strain w8 (S10), and Lactobacillus pentosus strain ml104 (S14). Different fruit puree formulations were produced using three strains, two inoculation ratios (4% and 5%), and two fermentation durations (24 and 48h). The physicochemical parameters (pH, total soluble solids, and color), total phenols content (TPC), total antioxidant capacity, bacterial viability, volatile aroma profile (VAP), and individual phenolic compound profile of fruit puree fermented for both 24 and 48h were compared with the unfermented (control) purees. The results of VAP were evaluated via PROMETHEE and cluster analysis. Time of fermentation and bacterial cultures at varied concentrations improved color values of samples (L*, a*, and b*) compared to controls. The level of bioactive compounds in several samples (S10 and S14) decreased after fermentation in contrast to S5 samples. The bacterial population in the samples ranged from ∼7.00 to 9.50 log CFU/g after 48-h fermentation. The fruit puree samples exhibited the presence of two different phenolic compounds and a total of 17 distinct volatile aroma compounds. The control sample scored highest for aromatic components in PROMETHEE, while S14-II was the most unique sample in cluster analysis. In conclusion, fermented probiotic fruit puree shown high promise as a carrier for live probiotics, and the fermentation process boosted the nutritional content of the fruit puree.

Detection of hypoglycaemia in type 1 diabetes through breath volatile organic compound profiling using gas chromatography-ion mobility spectrometry.

To evaluate the relationship between breath volatile organic compounds (VOCs) and glycaemic states in individuals with type 1 diabetes (T1D), focusing on identifying specific VOCs as biomarkers for hypoglycaemia to offer a non-invasive diabetes-monitoring method. Ten individuals with T1D underwent induced hypoglycaemia in a clinical setting. Breath samples, collected every 10-15 minutes, were analysed using gas chromatography-ion mobility spectrometry (GC-IMS). Correlation analysis and machine learning models, including Partial Least Squares Discriminant Analysis (PLS-DA) and Support Vector Machine classifiers, were used to classify glycaemic states based on VOC profiles. Statistical analysis revealed moderate correlations between specific VOCs (e.g. isoprene, acetone) and venous blood glucose levels. Machine learning models showed high accuracy in classifying glycaemic states, with the best performance achieved by a two-class PLS-DA model showing an accuracy of 93%, sensitivity of 92% and specificity of 94%. Key biomarkers identified included isoprene, acetone, 2-butanone, methanol, ethanol, 2-propanol and 2-pentanone. This study shows the potential of breath VOCs to accurately classify glycaemic states in individuals with T1D. While key biomarkers such as isoprene, acetone and 2-butanone were identified, the analysis emphasizes the importance of using overall VOC patterns rather than individual compounds, which can be markers for multiple conditions. Machine learning models leveraging these patterns achieved high accuracy, sensitivity and specificity. These findings suggest that breath analysis using GC-IMS could be a viable non-invasive method for monitoring glycaemic states and managing diabetes.

Physico-Chemical Properties and Chemical Analysis of Wildflower Honey Before and After the Addition of Spirulina (Arthrospira platensis).

In this study, in order to verify the effects due to the addition of spirulina (Arthrospira platensis) in a food product, a wildflower honey was analyzed in terms of chemical composition, physicochemical properties and antioxidant activity before and after the addition of the spirulina. HS-SPME/GC-MS and HPLC/UV were applied to carry out the chemical analyses. The obtained results demonstrated that the volatile profile and also the sugar content were significantly influenced by the addition of spirulina, showing significant qualitative and quantitative differences compared to honey without spirulina. The increase in HMF in honey added with spirulina was significant, demonstrating that its presence could accelerate the Maillard reaction. Electrical conductivity measured by using a conductometer was also increased while the moisture content was reduced in honey enriched with spirulina. Instead, the pH value was similar between the two samples. On the other hand, honey fortification with spirulina determined a significant increase of 12.5% in the total phenolic content (TPC), and a 56.25% increase in protein content. Further, the total antioxidant capacity (TAC) was also evaluated and a significant increase was determined as a result of the addition of spirulina. In conclusion, honey enriched with A. platensis was found to be characterized by a high pool of bioactive metabolites as well as significant changes in almost all the measurements performed.

Integrated volatolomics and lipidomics analysis reveal the characteristic flavor formation mechanism in steamed large yellow croaker (Pseudosciaena crocea)

The internal relationship between lipid composition and characteristic flavor in the steamed large yellow croaker (LYC) was investigated using volatolomics, lipidomics, and electronic sensory systems. Compared to fresh LYC, the concentrations of five key volatile flavor compounds detected after steaming exceeded human sensory thresholds. Notably, nonanal, hexanal, and 1-octen-3-ol significantly influenced the flavor of the cooked meat. Steaming at 70 °C enhanced the LYC flavor profile, with the strongest flavor observed at 80 °C. The content of three key volatile flavor compounds peaked, especially hexanal, which reached 54.55 μg/kg. Phosphatidylcholines, triacylglycerols, and fatty acids were closely associated with the volatile flavor profile of steamed LYC. The oxidation of FA 22:6 was identified as a crucial source of flavor in LYC. This study aimed to improve consumer experience by exploring the nutritional quality and flavor formation mechanisms in the thermal processing of LYC.

Dissecting negative effects of two root-associated bacteria on the growth of an invasive weed.

Plant-associated microorganisms can negatively influence plant growth, which makes them potential biocontrol agents for weeds. Two Gammaproteobacteria, Serratia plymuthica and Pseudomonas brassicacearum, isolated from roots of Jacobaea vulgaris, an invasive weed, negatively affect its root growth. We examined whether the effects of S. plymuthica and P. brassicacearum on J. vulgaris through root inoculation are concentration-dependent and investigated if these effects were mediated by metabolites in bacterial suspensions. We also tested whether the two bacteria negatively affected seed germination and seedling growth through volatile emissions. Lastly, we investigated the host specificity of these two bacteria on nine other plant species. Both bacteria significantly reduced J. vulgaris root growth after root inoculation, with S. plymuthica showing a concentration-dependent pattern in vitro. The cell-free supernatants of both bacteria did not affect J. vulgaris root growth. Both bacteria inhibited J. vulgaris seed germination and seedling growth via volatiles, displaying distinct volatile profiles. However, these negative effects were not specific to J. vulgaris. Both bacteria negatively affect J. vulgaris through root inoculation via the activity of bacterial cells, while also producing volatiles that hinder J. vulgaris germination and seedling growth. However, their negative effects extend to other plant species, limiting their potential for weed control.

Impact of Cucurbita and Cucumis rootstocks on the performance and quality of Piel de Sapo melon

Melon grafting represent an increasingly important strategy against biotic and abiotic stresses. Cucurbita hybrid rootstocks have been extensively developed for this purpose, but it is necessary to find new alternatives. In this work, several experimental rootstocks of cultivated and wild resources from the Cucurbita and Cucumis genera have been evaluated using Piel de Sapo melon as scion. Cucurbita rootstocks tended to increase fruit size and seed cavity and offered more rounded shapes at the early stages of ripening, but this effect was later minimised. Cucumis rootstocks tended to show less vigour than those of Cucurbita. C. metuliferus hybrid rootstock caused plant collapse at specific environmental conditions, probably due to differences in the growth of rootstock and scion. One of the Cucurbita maxima x C. moschata and the Cucurbita pepo experimental hybrids were also less vigorous, delaying flowering and fruit set, and compromising yield. The effects of Cucurbita and Cucumis rootstocks on sugar and acid accumulation of Piel de Sapo were almost negligible, but they altered the volatile profile. This last impact depended on the specific scion x rootstock interaction and the environmental conditions. Cucumis rootstocks tended to minimise it, especially the hybrid Cucumis melo subsp. melo x C. melo subsp. agrestis Pat 81, which offered a volatile profile highly resembling the non-grafted control. Among Cucurbita alternatives, the commercial hybrid Cucurbita maxima x C moschata had the lowest impact, while other experimental hybrids C. moschata x C. moschata and C. maxima x C. moschata increased levels of alcohols. Among Cucumis rootstocks, the hybrids of wild species Cucumis ficifolius x C. anguria and C. ficifolius x C. myriocarpus, and C. metuliferus had a higher impact on the volatile profile.

Electronic Nose Analysis of Exhaled Breath Volatile Organic Compound Profiles during Normoxia, Hypoxia, and Hyperoxia.

This study investigates volatile organic compound (VOC) profiles in the exhaled breath of normal subjects under different oxygenation conditions-normoxia (FiO2 21%), hypoxia (FiO2 11%), and hyperoxia (FiO2 35%)-using an electronic nose (e-nose). We aim to identify significant differences in VOC profiles among the three conditions utilizing principal component analysis (PCA) and canonical discriminant analysis (CDA). Our results indicate distinct VOC patterns corresponding to each oxygenation state, demonstrating the potential of e-nose technology in detecting physiological changes in breath composition (cross-validated accuracy values: FiO2 21% vs. FiO2 11% = 63%, FiO2 11% vs. FiO2 35% = 65%, FiO2 21% vs. FiO2 35% = 71%, and p < 0.05 for all). This research underscores the viability of breathomics in the non-invasive monitoring and diagnostics of various respiratory and systemic conditions.

Norisoprenoid Accumulation under Genotype and Vintage Effects in Vitis vinifera L. Wine Varieties

Norisoprenoids are important chemical compounds to grape and wine aroma, and their content in the grape berries can be greatly affected by varietal, terroir, and environmental factors. In this study, we investigate how major factors, such as genotype and climate conditions, influence the physicochemical properties of grape juice, volatile C13-norisoprenoid compounds, and gene expression profiles of three Vitis vinifera grape varieties: Muscat blanc à Petit grain, Muscat à petits grains rouges, and Gewürztraminer during the production period in 2010 and 2011. The total soluble solids (TSS) of both Muscat varieties were significantly higher in 2011 compared to 2010, reflecting interannual climatic variations, while Gewürztraminer showed no significant differences. At full maturity, total acid of all three cultivars was consistent between the years, indicating genetic determination. Thirteen norisoprenoids were identified, with Muscat varieties showing consistently higher levels than Gewürztraminer, irrespective of the production year. Varietal differences were significant for 13 out of 14 volatile compounds, and vintage effects were notable for 11 compounds, including key aroma contributors β-damascenone and β-ionone. OPLS-DA analysis highlighted distinct volatile profiles for each variety and vintage, influenced by climatic factors such as precipitation and sunlight hours. Gene expression analysis revealed strong correlations between VvCCD1, VvCCD4a, and VvCCD4b genes and C13-norisoprenoid accumulation, with these genes also implicated in the ABA biosynthesis pathway. Single nucleotide polymorphisms (SNPs) in VvCCD1, VvCCD4a, and VvCCD4b were linked to variations in norisoprenoid content among the cultivars. Altogether, these findings revealed the interaction of genetic and environmental factors in shaping the physicochemical properties for the grape, volatile profiles, and gene expression patterns of grape berries, with significant implications for viticulture and the winemaking process.

Low-calorie d-allulose as a sucrose alternative modulates the physicochemical properties and volatile profile of sponge cake.

d-Allulose, a C-3 epimer of d-fructose, is a rare sugar with ∼70% of the sweetness of sucrose but a caloric content of only 0.4kcal/g. Due to its low-calorie nature, d-allulose has garnered increasing interest in the food industry. This study was the first attempt to explore the effect of d-allulose as a sucrose replacer on the properties of sponge cake, a widely consumed high-sugar product. Substituting sucrose with d-allulose generated negligible impact on the batter system, while pronounced differences in physicochemical properties of cakes were detected, including specific volume, texture, microstructure, color, and antioxidant activity. In addition, sponge cake containing d-allulose displayed a distinctive aroma volatile profile, with more furans and pyrazines generation. Furthermore, correlations of physicochemical properties across all formulations were depicted, and the potential mechanism behind the property alterations modulated by d-allulose was revealed from the perspectives of starch gelatinization and browning reactions. Overall, this study provides insights into the application potential of d-allulose as a sucrose substitute in bakery product. PRACTICAL APPLICATION: This study elucidates the effect of d-allulose as a low-calorie sugar substitute on sponge cakes. This finding is valuable for the food industry, providing insights into a healthier alternative to traditional sugar in baked goods.