Concentrations Of Volatile Compounds Research Articles

Effects of Hexanal Supplementation on Volatile Compound Profiles and Quality Parameters of ‘Fuji Kiku’ Apples During Cold Storage and Shelf Life

The effects of hexanal supplementation in the storage atmosphere of ‘Fuji Kiku’ apples were investigated. The contents of volatile compounds (VOCs) in the headspace emitted by apple fruit during cold storage and in the headspace of apple fruit and juice during shelf life were determined. Hexanal treatment during storage significantly affected the VOC profile by stimulating the production or retention of key esters, including hexyl acetate, ethyl acetate, and butyl 2-methylbutanoate, during cold storage. Supplementation of hexanal also increased the production of linear esters, especially hexyl acetate, and promoted the formation of branched esters such as ethyl 2-methylbutanoate and hexyl 2-methylbutanoate during shelf life. Hexanal also increased the alcohol concentrations, with a significant increase in hexanol and 2-pentanol. Partial least squares discriminant analysis showed clear separation between control and hexanal-treated samples, with compounds like butyl hexanoate and 2-methyl-1-butanol being the most influential. Apple juice extracted from the flesh of hexanal-treated apples exhibited higher concentrations of key VOCs, including 2-methylbutyl acetate, hexyl acetate, and 2-methyl-1-butanol. No significant differences in firmness were observed; however, hexanal showed an inhibitory effect on the colour development of fruit. This study highlights the potential of hexanal in influencing aroma-related compounds and provides insight into strategies to improve postharvest aroma in apples.

Comparison of lignin degradation and flavor compound formation in roasted tobacco by two Bacillus subtilis strains

Two strains of Bacillus subtilis designated YY-10 and BY-2, were isolated from the surface of tobacco and found to be capable of significant lignin degradation. The predominant lignin-degrading enzymes produced by these strains were lignin peroxidase (LiP) and manganese peroxidase (MnP), respectively. A notable distinction was observed in the organoleptic evaluation and volatile flavor compounds, as determined by sensory evaluation and GC–MS analysis. The content of volatile flavor compounds, such as geranylacetone, meglumine trienone B, and meglumine trienone C, was found to be significantly increased in roasted tobacco treated with YY-10. This treatment has been shown to reduce the astringent flavor of the roasted tobacco and improve the aroma, which in turn could improve the quality of the roasted tobacco. Conversely, the quality and aroma levels of the roasted tobacco treated with the crude enzyme solution of the BY-2 strain were reduced. Transcriptome analysis revealed that the expression of genes related to amino acid metabolism, genetic material biosynthesis, and protein synthesis was up-regulated in the YY-10 strain compared with the BY-2 strain, which promoted the biosynthesis of LiP. This study provides a preliminary elucidation of the potential mechanism by which YY-10 enhances the quality of tobacco leaves through lignin-degrading enzyme production, thus establishing a research foundation for the subsequent treatment of waste tobacco raw materials and industrial applications.

Characterization of flavor profiles of water-boiled pork meatballs at different ultrasonic powers using solid-phase microextraction gas chromatography-mass spectrometry combined with electronic nose.

The objective of this study was to evaluate the flavor profiles of water-boiled pork meatballs at different ultrasonic powers (0, 150, 300, 450, 600, and 750W) using solid-phase microextraction gas chromatography-mass spectrometry (SPME-GC-MS) combined with electronic nose (E-nose). A total of 36 volatile compounds were determined by SPME-GC-MS, including alcohols, aromatic hydrocarbons, aldehydes, terpenes, alkanes, phenols, ketones, and other. With the appropriate ultrasound treatment, the type and relative content of volatile compounds were significantly increased (P<0.05), and the ultrasound treatment at 450W had the better effect on the flavor characteristics of pork meatballs. E-nose analysis also showed that the 450W ultrasound treatment had the highest response values of W1S, W6S, and W2S sensors (sensitive to hydrocarbons, alcohols, aldehydes, and ketones) to volatile compounds of pork meatballs. The characteristic flavor compounds of pork meatballs, including m-cresol, limonene, nonanal, and linalool, were further confirmed by comparing the content, partial least squares discriminant analysis (PLS-DA), and odor activity value (OAV). Overall, appropriate ultrasound-assisted cooking (especially at 450W) could be a promising approach to enhance the flavor profiles of pork meatballs.

Compositional Changes of Volatile Organic Compounds in Biogases and Biomethanes Depending on the Feedstock in Sweden

Biogas usually contains volatile organic compounds such as terpenes, siloxanes, halogenated hydrocarbons, ketones, alcohols, furans and esters whose presence in the biogas is highly dependent on the feedstock. These trace components can affect the integrity of the materials they come into contact with, e.g., equipment, pipelines and engines, and their presence in the gas may pose health, safety and environmental risks. Understanding the composition of gases is a prerequisite to ensure the correct function of gas infrastructure, appliances and vehicles. This study examined how volatile organic compound (VOC) content in biogas varies depending on the feedstock and evaluated the efficiency of different upgrading processes in removing VOCs. The data, primarily collected in Sweden, include biogases produced in digesters and landfills. The selection of VOCs included in this study was based on extensive analysis of samples collected from numerous biogas and biomethane industrial facilities over an extended period, providing a comprehensive overview of VOC composition. The conducted research is intended to serve as a basis for more systematic studies on the influence of process parameters and feedstock composition on the formation of VOCs. The data have multiple potential uses, including predicting which VOCs would be found in biomethane for a given feedstock and upgrading techniques. Additionally, these data can also be used in standardization discussions to assess the plausibility of the proposed limit values and the need to regulate additional compounds.

Changes in Volatile Compounds and Sensory Properties of Chicken with Armillaria mellea During the Pressure-Cooking Process.

Chicken with Armillaria mellea prepared via pressure cooking is a traditional Chinese delicacy with great potential for food development. Optimizing its cooking time is crucial. In this study, chicken and Armillaria mellea were pressure-cooked for different amounts of time (20 min, 25 min, 30 min, 35 min, and 40 min). In total, 101 and 81 volatile compounds were identified by GC-MS and GC-IMS, respectively. The results showed that the content of volatile compounds was the highest at 40 min. Nonanal, decanal, (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, and 1-octen-3-ol were identified as the most critical aroma compounds at this time, which brought unique fat, oil, and mushroom aroma to chicken with Armillaria mellea during the pressure-cooking process. The optimal time was determined to be 35 min through sensory properties. In summary, the optimal cooking time for chicken with Armillaria mellea prepared via pressure cooking is 35-40 min. Our research results not only preliminarily determined the optimal conditions for industrial processing of the prepared dish of with Armillaria mellea prepared via pressure cooking, laying a foundation for the later industrial production of prepared dishes and international sales, but also stimulated innovative composite food development and promoted people's exploration of the mechanism of heat treatment on composite food flavor and taste.

Effects of Lactiplantibacillus plantarum on Metabolites and Flavors in Synthetic Microbiota During Baijiu Fermentation.

The distinctive flavor and aroma of Chinese baijiu are closely linked to the microorganisms involved in the fermentation process. Lactiplantibacillus plantarum, a dominant species in the fermentation of Chinese baijiu, has become a prominent research focus. In this study, we selected well-characterized pure cultures of microorganisms to construct diverse chassis microflora. The primary objective was to investigate the effects of L. plantarum on the fermentation process of Chinese baijiu and its association with metabolites produced by different chassis microflora. Our results demonstrated that the concentrations of ethyl lactate and other volatile aromatic compounds increased in all fermentation protocols where L. plantarum was added. The addition of L. plantarum also significantly increased the concentration of total organic acids, particularly lactic acid, which rose by 17 to 123 times. Furthermore, L. plantarum helped maintain the stability of ethanol concentration during the middle and late stages of fermentation. Notably, among the three different chassis microbial fermentation protocols involving L. plantarum, the protocol with the highest microbial diversity exhibited a greater capacity to produce lactic acid (1.56 ± 0.19 mg/g), ethanol (5.74 ± 0.47 mg/g), and reducing sugars (6.39 ± 0.31 mg/g). These findings provide valuable insights into the potential of L. plantarum for modulating the flavor of Chinese baijiu.

Influence of Organic Nitrogen Derived from Recycled Wine Lees and Inorganic Nitrogen on the Chemical Composition of Cabernet Sauvignon Wines Fermented in the Presence of Non-Saccharomyces Yeasts Candida boidinii, C. oleophila, and C. zemplinina.

In this study, the influences of inorganic nitrogen source (INS) and organic nitrogen source (ONS) supplementation during the wine fermentation process using three non-Saccharomyces yeasts (Candida zemplinina, Candida oleophila, and Candida boidinii) were analyzed. Diamine phosphate (DAP) was used as an INS, and lees enzymatic hydrolysate was used as an ONS. Complete alcoholic fermentation and a higher concentration of volatile compounds were obtained in fermentations with ONS, mainly esters from 81 to 4564 µg/L, alcohols from 231 to 7294 µg/L, and isoamyl acetate ester compounds from 12.3-22.8 ppb, with a very marked odorant activity value (OAV). In addition, malic acid was detected due to its influence on yeast metabolism and, consequently, on aroma production. Using a Y15 enzymatic autoanalyzer, residues of 1.30 g/L in ONS and 1.35 g/L in INS were obtained on the last day of alcoholic fermentation. In summary, we obtained promising results concerning the production of wine with enhanced functionalities due to higher concentrations of some volatile and polyphenolic compounds.

Comprehensive Analysis of Volatile Organic Compounds and Their Impact on Apple Quality Following Some Essential Oil Treatments Against Botrytis cinerea

The susceptibility of apples to post-harvest decay by the fungus Botrytis cinerea has prompted innovative research into alternative preservation methods. In this regard, essential oils (EOs) have emerged as promising candidates due to their natural origin and potential antimicrobial properties. Investigating the biological significance of EO blends is crucial for understanding their potential antimicrobial mechanisms and evaluating their capacity to modulate metabolic responses that could inhibit post-harvest fungal decay in fruit tissues. This study delves into the intricate chemistry of apples when subjected to various EO treatments, shedding light on the profound changes in alcohols, esters, C6 compounds, terpenes, and volatile compounds. Based on our results, terpene concentrations exhibit significant variations with α-Pinene ranging from 13.4 µg L−1 in Fungus + Thymol + 1,8-Cineole treatment (Fun+Thy+Cin) to 28.7 µg L−1 in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug), and β-Pinene concentrations spanning 19.3 µg L−1 in Fungus + 1,8-Cineole + Eugenol treatment (Fun+Cin+Eug) to 45.5 µg L−1 in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug). Ester elaboration presents marked changes, with ethyl octanoate peaking at 715.7 µg L−1 in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug) and ethyl propionate reaching 152.9 µg L−1 in Fungus + Thymol treatment (Fun+Thy). The volatile compound dynamics also demonstrate significant variations, with hexanoic acid concentrations ranging from 0.1 to 0.2 among treatments and 3-Methylbutanal displaying concentrations from 0.8 to 6.4, with the highest concentration observed in the Control. The essential oil combination of Thymol, Eugenol, and 1,8-Cineol (Fun+Thy+Cin+Eug) had the most significant impact on the volatile compound content in the fruits. The findings from this study unveil the intricate responses of apple chemistry to various EO treatments. These insights hold promise for enhancing post-harvest apple preservation strategies through the modulation of EO treatments.

Development of Volatile Compounds in Raw Fermented Sausages with Reduced Nitrogen Compounds—The Effect of Tomato Pomace Addition

The aim of this study was to assess the impact of tomato pomace (TP) on the content of volatile compounds and L-carnitine and the sensory characteristics of raw fermented sausages produced with reduced nitrite. The produced sausages were divided into three experimental groups: control sample, sample with 1.5% addition of freeze-dried tomato pomace, and sample with 2.5% addition of TP. The results showed that the addition of tomato pomace significantly affected the quality of raw fermented sausages. Lower L-carnitine content was observed in samples with TP. The main groups of volatile compounds identified in fermented sausages were alcohols, aldehydes, hydrocarbons, and ketones. The addition of TP influenced the smell and taste of the sausages, which were characterized by a more intense tomato taste and smell and more intense red color compared to the control sample. Despite the influence of TP addition on some sensory features, the products were characterized by a high score of overall quality of over 7 c.u. on a 10-point scale, similar to the control sausage.

Influences of Drying Conditions on Quality Attributes, Taste and Volatile Compounds of Celery Leaves

Celery leaves account for 5–10% of the celery weight and are rich in nutrients, but they are usually discarded as waste. To explore this resource, hot-air drying (HA), intermittent hot-air drying (IHA-A and B), vacuum hot-drying and freeze-drying (VH and VF) were used to systematically investigate the effects of drying conditions on quality attributes, taste and volatile compounds of celery leaves. VF could better maintain the quality attributes, while IHA-B leaves were rich in taste and volatile components. The results indicated that both drying temperature and vacuum environment had significant effects on quality attributes. In terms of taste, reducing the drying temperature enriched the taste of celery leaves; however, in vacuum drying, the high temperature could contribute to increase the contents of total free amino acids and bitter amino acids. For volatile compounds, different drying conditions gave celery leaves different aromas, and IHA treatments resulted in a significantly higher content of volatile compounds than other treatments.

Effect of Lime Solution Soaking on Physicochemical Characteristics of Catfish Bone Powder (Arius thalassinus)

Fish bone powder is one of the fisheries by product processing that has a high nutritional content, especially calcium and phosphorus content. In the processing of fish bone powder, the fishy odor is still detected due to organic compound such as protein and lipid which produce volatile compounds yielded unpleasant odor. The use of lime can eliminate fishy odors, improve color, shape, taste, texture, and extend shelf life. This study aimed to determine the difference of lime solution concentration on the physicochemical characteristics of catfish bone powder and to determine the best lime concentration used on the volatile compound content of catfish bone powder. The method carried out in this study was a laboratory experimental method and used a Complete Random Design (CRD) with 4 treatments (0%, 15%, 20%, 25%) and carried out in triplicate. Data analysis from physical and chemical tests were analyzed using ANOVA, while hedonic tests were performed using the Kruskal-Wallis test followed by the Mann-Whitney test. The results showed that soaking lime solution had a significant effect (P&lt;5%) on moisture content, protein content, fat content, ash content, calcium content and color. Catfish bone powder with the best treatment of soaking in lime solution of 20% contained a calcium of 25.17%.The results of the hedonic test showed that the best treatment (20%) had a confidence interval of 3.95 &lt; μ &lt; 4.19 from 5 scale. The volatile compound of 4-[4-(dimethylamine) Benzaldehyde associated with fishy odor was detected in fish bone powder without lime solution, but it could not be detected in sample soaked in 20% lime solution showing the capability of lime solution to reduce fishy odor in fishbone powder.

New insights into the drying technology of Pleurotus eryngii: Effects on protein structure, properties and product flavor analysis

Drying techniques have been widely used in food macromolecule modification, sterilization, and other fields. However, comparisons about the effects of different heat treatments on the structural and functional properties of proteins have yet to be elucidated. In this study, we compared the effects of boiling water, microwave, hot air, and infrared pretreatment on the structural and functional properties of P. eryngii (Pleurotus eryngii) proteins (PEP), with the addition of low-temperature hot air drying (Fresh-H) and vacuum freeze drying (VFD) as controls. The flavor of apricot mushroom products was also analyzed. The results showed that the PEP from boiling water pretreatment combined with hot air drying (BPHD) maintained high surface hydrophobicity, turbidity, particle size, and zeta potential. Microwave pretreatment combined with hot air drying (MPHD) of PEP had higher water and oil-holding properties, crystallinity, hydrolysis, and antioxidant capacity. Meanwhile, both MPHD and infrared pretreatment combined with hot air drying (IPHD) maintained higher emulsification, foaming, and free amino acid content. There were large differences in the types and contents of volatile compounds in P. eryngii with different treatments, providing more options.

Headspace Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry Combined with Sensory Evaluation for the Analysis of Volatile Aromatic Compounds in Apricot (Prunus armeniaca L.) Germplasm Resources Cultivated in Xinjiang, China.

The volatile compounds in the fruits of 24 apricot cultivars were quantitatively and qualitatively determined via headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of 429 volatile compounds were detected in these fruits, and the greatest number of detected terpenoids was 77. Significant differences were found among the cultivars in terms of the total volatile compound content of the fruits, with variation from 112.76 ('ZSHYX') to 317.36 µg/g ('JNL'). Using relative odor activity value (rOAV) analysis, 42 key aroma compounds were identified. The rOAVs of (2S,4R)-4-methyl-2-(2-methylprop-1-enyl)oxane, (E)-non-2-enal, (3-methyl-3-sulfanylbutyl) formate, and thiophen-2-ylmethanethiol were above 1000, and most had green, fruity, and woody odors; these results indicated that these substances were important contributors to the overall aroma of the apricot fruits. Our study provides a comprehensive analysis of the volatile compounds from 24 representative apricot cultivars and can aid in the further scientific understanding of the metabolites and aroma in apricots. These findings provide a reference for controlling fruit quality and for future apricot cultivar breeding.

Exploring the freshness biomarker and volatiles formation in stored pork by means of lipidomics and volatilomics

Raw pork is prone to oxidation and rancidity as it contains a high level of unsaturated lipid molecules. Reliable biomarkers to benchmark pork freshness and their formation have not been systematically investigated. The results indicated that the peroxide values, TVB-N and rancid volatiles dramatically increased in pork during the storage period (4 °C, 0–9 d). Concentrations of most volatile compounds with carbonyl groups were increased markedly in pork during storing, including hexanal, acetic acid, and hexadecanoic acid methyl ester. Lipidomics, volatilomics and chemometrics methods were used to discriminate the freshness of pork, among which acetic acid and PC O-20:3 emerged as the most reliable freshness biomarkers. Phospholipids and neutral lipids, including phosphatidylcholines (PC), triglycerides (TG), and phosphatidylethanolamine (PE), played a crucial role in the formation of rancid volatiles and the decreased freshness. This work will provide technical supports for the efficient storage and preservation of raw meat.

Volatile markers for unifloral safflower honey: An untargeted and targeted metabolomics analysis.

The volatile markers and aroma properties of unifloral safflower honey in Xinjiang, China were identified for the authentication. An untargeted metabolomics analysis was performed to compare the volatile components in safflower honey with those in four other unifloral honey and the nectar plants of safflower honey through headspace solid-phase microextraction-chromatography-mass spectrometry. Tentative markers, including benzaldehyde, longifolene, and cedrol, were comprehensively screened through variable importance in projection based on orthogonal partial least-squares discrimination analysis, nectar origin volatile components analysis, and odor characteristics analysis. A targeted quantitative analysis of potential volatile compound contents within safflower honey between 2021 and 2023 provided valuable evidence for differentiating safflower honey and other honey. Furthermore, bacterial inhibition tests showed that safflower honey exhibits inhibitory activity against Escherichia coli, with efficacy comparable to control. The reliable volatile markers, longifolene, and cedrol, enhance safflower honey's antibacterial effect.

Determination of the quantitative content of volatile components in ethanol-containing products

A method is proposed for correctly determining the quantitative content of volatile components, including ethyl alcohol, in alcohol-containing products. The method is based on the use of sample density measurement data and chromatographic data for determining the quantitative content of volatile compounds. It is shown that in a number of cases the difference between the values of the volumetric content of ethyl alcohol in alcoholic products, calculated according to the interstate standard GOST 3639 and according to the proposed method, exceeds by several times the declared measurement error limit of 0.1 % by volume. The results obtained can be used to update state, interstate and international standards for quality control and safety of alcoholic and alcohol-containing products.

Volatile Compounds of Sucuk, a Dry Fermented Sausage: The Effects of Ripening Rate, Autochthonous Starter Cultures and Fat Type.

The aim of this study was to determine the effects of ripening rate (slow or fast), usage autochthonous starter cultures (control-spontaneous fermentation, Lactiplantibacillus plantarum GM77, Staphylococcus xylosus GM92 or L. plantarum GM77 + S. xylosus GM92) and type of fat (beef fat-BF, sheep tail fat-STF and BF+STF) on the volatile compounds of sucuk (a Turkish dry fermented sausage). A total of 74 volatile compounds were identified, including groups of aliphatic hydrocarbons, aldehydes, ketones, alcohols, sulfide compounds, esters, aromatic hydrocarbons, nitrogenous compounds, acids and terpenes in sucuk. Slow ripening resulted in significant increases in the abundance of ethanol, acetic acid, ethyl acetate, acetoin and diacetyl. A similar situation was determined for a mixed culture (L. plantarum + S. xylosus). Correlation analysis showed that the effects of slow ripening and mixed culture use were more pronounced in terms of volatile compound content. Although the effect of fat type on volatile compounds was quite limited compared to other factors, correlation analysis showed that STF had a different volatile compound profile.

Evaluating the Potential of Legume-Based Wort for Brewing Applications

The study aims to enhance sustainability in the brewing industry by exploring the use of legumes as eco-friendly substitutes for barley, given their lower greenhouse gas emissions. The physicochemical properties of Congress wort made from both raw and malted forms of five legumes were investigated: red lentil, beluga lentil, green peas, fava bean, and mung bean. These legumes were tested at inclusion levels of 10, 30, 50, and 100% in the mashing process. The effect of adding exogenous enzymes to improve extract yield and filtration efficiency was also tested. Malting the legumes increased extract yield and free amino nitrogen (FAN) concentration while decreasing polyphenol and protein content compared to raw legumes. The malted legumes also had higher concentrations of volatile aroma compounds compared to their raw counterparts. Worts with mung bean had the most distinct aroma profile compared to other legume wort. At lower inclusion levels (10–30%), adding malted legumes did not negatively affect wort quality. However, at a 50% inclusion level, the use of exogenous enzymes improved wort characteristics with more pronounced effects in malted legumes. These findings highlight the potential of locally sourced legumes as sustainable barley alternatives in brewing, even at high inclusion levels. However, the environmental impact of the whole supply chain needs to be clarified in future studies.

Identification of Floral Fragrance Components in 20 Intersectional Hybrids of Paeonia in Luoyang Region

ABSTRACTIntersectional hybrids of Paeonia (Paeonia Itoh hybrids) have rich colours and strong fragrance, combining the advantages of sect. Moutan and sect. Paeonia, and have great economic value and development potential. However, there have been few studies on the floral fragrance components of intersectional hybrids of Paeonia. In this study, the types and contents of volatile components of 20 intersectional hybrids of Paeonia were conducted. A total of 53 floral volatiles were identified though gas chromatography–mass spectrometry (GC–MS) analysis, with linalool, nonanal and phenylethyl alcohol as the main floral components. Based on the compound contents and odour activity values (OAVs) analysis, the 20 cultivars were classified into four aroma types: a floral scent, a fresh floral scent, a floral with spicy scent and a fruity scent. ‘Magical Mystery Tour’ had the highest volatile compound contents and OAVs, and had potential for exploitation. This study provided a theoretical reference for the selection of parents for flower fragrance breeding of Paeonia Itoh hybrids.

Volatile compounds and fatty acids of mixture herbal product Pectorales Species No 2

Pectorales species No. 2 is a multicomponent herbal preparation with expectorant and anti-inflammatory effects. It includes coltsfoot leaves, plantain leaves, and licorice roots. This study focused on assessing the composition and content of volatile compounds and fatty acids in Pectorales species No. 2. The volatile compounds and fatty acids profile was assessed by GC-MS and GC-FID respectively. It is represented by 24 fatty acids and 91 volatile compounds. The main fatty acids in the composition of Pectorales species No. 2 are palmitic, linoleic and α-linolenic acids. The prevailing volatile lipophilic compounds are carvone, isomentone, iso-octenyl alcohol, anethole, hexyl alcohol, menthanone, cis-hex-3-enyl alcohol, benzaldehyde, pulegone, linalool, α-thujone.