Unique Volatile Compounds Research Articles

Exploring the potential of red pitaya pulp (Hylocererus sp.) as a plant-based matrix for probiotic delivery and effects on betacyanin content and flavoromics

This study evaluated the potential of red pitaya pulp fermented with Lacticaseibacillus paracasei subsp. paracasei F-19 (F-19) as a base for probiotic products. Physicochemical parameters, sugar, betacyanin, and phenolic contents, and antioxidant activity were analyzed over 28 days at 4 °C and compared to a non-fermented pulp, and to a pulp fermented with Bifidobacterium animalis subsp. lactis BB-12 (BB-12). Volatile compounds were identified using HS-SPME/GC–MS. Probiotic viability during storage and survival through in vitro-simulated gastrointestinal tract (GIT) stress were assessed. Red pitaya pulp, rich in moisture (85.83 g/100 g), carbohydrates (11.65 g/100 g), and fibers (2.49 g/100 g), supported fermentation by both strains. F-19 and BB-12 lowered pH, with F-19 showing stronger acidification, and maintained high viability (8.85–8.90 log CFU/mL). Fermentation altered sugar profiles and produced unique volatile compounds, enhancing aroma and sensory attributes. F-19 generated 2-phenylethanol, a unique flavor compound, absent in BB-12. Phenolic content initially increased but antioxidant activity decreased during storage. Betacyanin remained stable for up to 14 days. Red pitaya improved F-19 viability through the simulated GIT, while BB-12 populations significantly decreased (p < 0.05). These results suggest red pitaya pulp is a promising plant-based matrix for F-19, offering protection during digestion and highlighting its potential as a functional food with enhanced bioactive compound bioavailability and sensory attributes.

Effect of thermosonication on the bioactive peptide profile, volatile compounds, and fatty acid profile of Minas Frescal cheese

This study investigated the effect of thermosonication (TS) of milk on the bioactive peptide profile, fatty acid composition, and volatile compounds of Minas Frescal cheese. Five cheese formulations were prepared: raw milk (Control), pasteurized milk (High-Temperature Short-Time or HTST) (72–75 °C/15 s), and milk treated by TS at nominal powers of 160 W (TS160), 400 W (TS400), and 640 W (TS640). The fatty acid profile and health indices did not change significantly after HTST or TS. TS, mainly TS400 treatment, increased the number of bioactive peptides with antihypertensive, antioxidant, immunomodulatory, and antimicrobial activities and promoted the formation of unique volatile organic compounds, mainly from the ester and fatty acid groups. In conclusion, TS can be considered by the dairy industry as an interesting alternative for manufacturing Minas Frescal cheese, resulting in products with greater functional potential and unique volatile compounds and keeping the fatty acid profile unchanged.

Analysis of volatile compounds in roasted Liberica Coffee in the Philippines by gas chromatography mass spectrometry

The study is aimed at evaluating volatile compounds of Liberica coffee (Coffea liberica) collected from Lipa Batangas. Sample analysis was performed using Static Headspace Gas Chromatography. The roasting process also generated furans, pyridines, aldehydes ,and pyrazines potent volatile compounds in Liberica beans including unique volatile compounds including Terpinene 4-acetate (0.65%) and trans-β-Ocimene (0.47%). Furthermore, the presence of the abovementioned compounds revealed the essential marker as Liberica coffee beans. This finding may help to add more information with regards to the volatile compounds of Liberica Coffee.

Unique Volatile Compounds of Sea Cucumber Beer and its Anticoagulant Activity

Unique Volatile Compounds of Sea Cucumber Beer and its Anticoagulant Activity

Carcass meat quality, volatile compound profile, and gene expression in Tan sheep under different feeding regimes

The formation mechanism of volatile compounds in Tan lamb meat under different feeding regimes remains unclear. This study aimed to determine whether the volatile compounds in meat are related to lipid metabolism in an attempt to improve the theoretical basis for increasing the yield and quality of lamb production. Results showed that the specialized pasture grazing with indoor feeding (GF) and indoor feeding only (F) regimes had advantages in terms of growth and carcass traits compared to the specialized pasture grazing only (G) regime. Lamb meat qualities of the GF group were in an intergrade position compared to those of the F and G groups. Although the lamb meat of the three groups had different aroma attributes, as measured using SPME-GC-MS, GF lamb meat had the most pleasant active compounds. In contrast, the expression of lipid transport genes was altered in all three groups. In summary, Tan lambs had different growth performance, intramuscular fat content, and composition under the three feeding regimes, which might be due to the differences in energy and lipid transport, resulting in unique volatile compound profiles in meat from different groups.

Fungal Biomarkers in Traditional Starter Determine the Chemical Characteristics of Turbid Rice Wine from the Rim of the Sichuan Basin, China.

The fungal community in Qu plays a key role in the formation of turbid rice wine (TRW) style. The Sichuan Basin and its surrounding areas have become one of the main TRW production regions in China; however, the fungal community in Qu and how they affect the characteristics of TRW remain unknown. Therefore, this study provided insight into the fungal biomarkers in Qu from Guang'an (GQ), Dazhou (DQ), Aba (AQ), and Liangshan (LQ), as well as their relationships with compounds in TRW. The main biomarkers in GQ were Rhizopus arrhizus, Candida glabrata, Rhizomucor pusillus, Thermomyces lanuginosus and Wallemia sebi. However, they changed to Saccharomycopsis fibuligera and Mucor indicus in DQ, Lichtheimia ramose in AQ, and Rhizopus microsporus and Saccharomyces cerevisiae in LQ. As a response to fungal biomarkers, the reducing sugar, ethanol, organic acids, and volatile compounds were also changed markedly in TRWs. Among important volatile compounds (VIP > 1.00), phenethyl alcohol (14.1-29.4%) was dominant in TRWs. Meanwhile, 3-methyl-1-butanol (20.6-56.5%) was dominant in all TRWs except that fermented by GQ (GW). Acetic acid (29.4%) and ethyl palmitate (10.1%) were dominant in GW and LW, respectively. Moreover, GQ biomarkers were positively correlated with acetic acid and all unique important volatile compounds in GW. DQ biomarkers had positive correlations with unique compounds of acetoin and ethyl 5-chloro-1,3,4-thiadiazole-2-carboxylate in DW. Meanwhile, the AQ biomarkers were positively correlated with all AW unique, important, and volatile compounds. Although there were not any unique volatile compounds in LW, 16 important volatile compounds in LW were positively related to LQ biomarkers. Obviously, biomarkers in different geographic Qu played vital roles in the formation of important volatile compounds, which could contribute specific flavor to TRWs. This study provided a scientific understanding for future efforts to promote the excellent characteristics of TRW by regulating beneficial fungal communities.

A comparative study of in-vitro and in-silico anti-candidal activity and GC-MS profiles of snow mountain garlic vs. normal garlic.

The study aimed to profile the volatile phytocomposition of snow mountain garlic (SMG) compared to normal garlic and investigate the anti-Candida efficacy against clinically relevant multi-drug resistant isolates of Candida species. Herein, SMG has shown significantly superior fungicidal power at 2x-MIC dose against C. albicans and C. glabrata in killing kinetic evaluation unlike the fungistatic effect of normal garlic. GC-MS headspace-based profiling of SMG showed 5 unique volatile compounds and a 5-fold higher content of saponins than normal garlic. In an in-silico analysis, cholesta-4,6-dien-3-ol,(3-beta) was uniquely identified in SMG as a potential inhibitor with high binding affinity to the active site of exo-1,3-betaglucan synthase, an established anti-candida drug target crucial for the biofilm matrix formation, thus suggesting a plausible anti-Candida mechanism. The in-vitro and in-silico studies have demonstrated the Candida-cidal and anti-biofilm activities of SMG, distinguishing it from the Candida-static efficacy of normal garlic. This is the first report that identifies several phytochemical signatures of SMG along with a potential anti-Candida compound, that is cholesta-4,6-dien-3-ol,(3-beta)-, which appears worthy of detailed studies in the future to explore the utility of SMG as a fungal phytotherapy agent, especially against drug-resistant Candida sp.

The Use of γ-Aminobutyric Acid-Producing Saccharomyces cerevisiae SC125 for Functional Fermented Beverage Production from Apple Juice.

The development of functional fermented beverages enriched with γ-aminobutyric acid (GABA) has been pursued because of the health benefits of GABA; however, few studies have described GABA production by yeast. Therefore, this study aimed to produce fermented apple beverages enriched with GABA produced by Saccharomyces cerevisiae SC125. Golden Delicious apples were fermented by S. cerevisiae SC125 to produce a novel functional beverage; commercial yeast was used as the control. The GABA, organic acid, and volatile compound content during the fermentation process was investigated by high-performance liquid chromatography and headspace solid-phase microextraction/gas chromatography-mass spectrometry. A yield of 898.35 ± 10.10 mg/L GABA was achieved by the efficient bioconversion of L-monosodium glutamate. Notably, the S. cerevisiae SC125-fermented beverage produced several unique volatile compounds, such as esters, alcohols, 6-decenoic acid, and 3-hydroxy−2-butanone, and showed significantly enhanced contents of organic acids, including malic acids, citric acid, and quinic acid. Sensory analysis demonstrated that the S. cerevisiae SC125-fermented apple beverage had improved aroma, flavor, and overall acceptability. In conclusion, a fermented functional apple beverage containing GABA was efficiently produced using S. cerevisiae SC125.

Characterization of the Volatile Compounds in Camellia oleifera Seed Oil from Different Geographic Origins.

Volatile flavor of edible oils is an important quality index and factor affecting consumer choice. The purpose of this investigation was to characterize virgin Camellia oleifera seed oil (VCO) samples from different locations in southern China in terms of their volatile compounds to show the classification of VCO with respect to geography. Different samples from 20 producing VCO regions were collected in 2020 growing season, at almost the same maturity stage, and processed under the same conditions. Headspace solid-phase microextraction (HS-SPME) with a gas chromatography–mass spectrometer system (GC–MS) was used to analyze volatile compounds. A total of 348 volatiles were characterized, including aldehydes, ketones, alcohols, acids, esters, alkenes, alkanes, furans, phenols, and benzene; the relative contents ranged from 7.80–58.68%, 1.73–12.52%, 2.91–37.07%, 2.73–46.50%, 0.99–12.01%, 0.40–14.95%, 0.00–27.23%, 0.00–3.75%, 0.00–7.34%, and 0.00–1.55%, respectively. The VCO geographical origins with the largest number of volatile compounds was Xixiangtang of Guangxi (L17), and the least was Beireng of Hainan (L19). A total of 23 common and 98 unique volatile compounds were detected that reflected the basic and characteristic flavor of VCO, respectively. After PCA, heatmap and PLS-DA analysis, Longchuan of Guangdong (L8), Qingshanhu of Jiangxi (L16), and Panlong of Yunnan (L20) were in one group where the annual average temperatures are relatively low, where annual rainfalls are also low. Guangning of Guangdong (L6), Yunan of Guangdong (L7), Xingning of Guangdong (L9), Tianhe of Guangdong (L10), Xuwen of Guangdong (L11), and Xiuying of Hainan (L18) were in another group where the annual average temperatures are relatively high, and the altitudes are low. Hence, volatile compound distributions confirmed the differences among the VCO samples from these geographical areas, and the provenance difference evaluation can be carried out by flavor.

Unique volatile chemical profiles produced by indigenous and commercial strains of &lt;i&gt;Saccharomyces uvarum&lt;/i&gt; and &lt;i&gt;Saccharomyces cerevisiae&lt;/i&gt; during laboratory-scale Chardonnay fermentations

Each wine growing region hosts unique communities of indigenous yeast species, which may enter fermentation and contribute to the final flavour profile of wines. One of these species, Saccharomyces uvarum, is typically described as a cryotolerant yeast that produces relatively high levels of glycerol and rose-scented volatile compounds as compared with Saccharomyces cerevisiae, the main yeast in winemaking. Comparisons of fermentative and chemical properties between S. uvarum and S. cerevisiae at the species level are relatively common; however, a paucity of information has been collected on the potential variability present among S. uvarum strains. The objective of this study was to compare the fermentation kinetics and production of volatile compounds between indigenous and commercial Saccharomyces strains at different temperatures. We compared laboratory-scale fermentation of Chardonnay juice at 15 °C and 25 °C for 11 Saccharomyces yeast strains (six indigenous S. uvarum, one commercial S. uvarum, one indigenous S. cerevisiae and three commercial S. cerevisiae). Fermentation kinetics and the production of volatile compounds known to affect the organoleptic properties of wine were determined. The indigenous S. uvarum strains showed comparable kinetics to commercially sourced strains at both temperatures. Volatile compound production among the strains was more variable at 15 °C and resulted in unique chemical profiles at 15 °C as compared with 25 °C. Indigenous S. uvarum strains produced relatively high levels of 2-phenylethyl acetate and 2-phenylethanol, whereas these compounds were found at much lower levels in fermentations conducted by commercial strains of both S. cerevisiae and S. uvarum. Production of glycerol by indigenous S. uvarum strains did not differ from commercial strains in this study. Our findings demonstrate that indigenous strains of S. uvarum show functional variation among themselves. However, when compared with commercial S. cerevisiae and S. uvarum strains, they have comparable fermentation kinetics but unique volatile compound profiles, especially at low fermentation temperatures.

Differences in New Zealand Hop Cultivars Based on Their Unique Volatile Compounds: An Integrated Fingerprinting and Chemometrics Approach.

Hop aroma characteristics originate from hop essential oils, which have complex chemical profiles that remain poorly understood, particularly for New Zealand hops. The aim of this study was to determine volatile compounds that distinguish New Zealand hop cultivars. Untargeted fingerprinting methods based on headspace gas chromatography mass spectrometry (GC-MS) were used to analyse nine hop cultivars. A total of 61 volatile compounds were identified as compounds that differentiated the commercial hop varieties using advanced chemometrics and feature selection techniques. Similarities in volatile composition were found between Wakatu, Wai-iti™ and Kohatu®, which are rich in alcohols. Another grouping was found between Waimea™ and Nelson Sauvin™, where ketones and esters were commonly found. Rakau™ was distinct from the other eight cultivars, distinguished by 2-methylbutyl 3-methylbutanoate and methanethiol hexanoate. Riwaka™ contained the greatest number of discriminating volatile compounds when compared to other cultivars, which was dominated by terpenoids, such as geranyl 2-methylbutanoate, perillene and D-limonene. The chemical fingerprinting approach successfully identified volatile compounds that had not been previously found in New Zealand hop cultivars and that discriminated the commercial cultivars. The data obtained in the present study further extend the knowledge of New Zealand hops and will help facilitate targeted breeding.

Insights into the chemosensory basis of flavor in table grapes.

The full flavor of grape berries is determined by the interaction of sugars, acids, volatile compounds, and other berry properties, such as astringency. Sugars and acids are important for berry taste, whereas volatile compounds are important for the unique berry flavors, e.g., monoterpenes for the Muscat varieties. We explored the basis for 'fruity' flavor perception in table grapes. Samples were collected from 134 new table grape lines and commercial varieties and tested chemically for their volatile profiles and organoleptically by tasting panels. At the sensory level, flavor impression was strongly correlated with berry preference, whereas among 'fruity', 'neutral', 'herbaceous,' and 'Muscat', only the 'fruity' flavor was correlated with berry preference. At the chemical level, 114 volatile compounds were detected in the 81 breeding lines and cultivars examined, and grouped into 'core' and 'unique' categories. The typical berry flavor seemed to depend on the major volatile aldehydes-1-hexanal and (E)-2-hexenal-accounting for up to an average 85% of the berry's core volatile concentration. We found four volatile compounds-α-bergamotene, geranyl formate, aristolene and α-penansinene-previously undetected, to our knowledge, in fresh grape berries. High 'fruity' flavor scores were related to three independent factors: (i) presence of unique volatile compounds, such as the sesquiterpene α-copaene, (ii) higher total concentration of volatile compounds, (iii) optimal maturity associated to high total soluble solids (TSS) levels, interacting with berry volatile composition. These combined sensory and analytical data on the flavor of table grapes improve our understanding of the complex interface between chemical and sensory perception in fruit. © 2019 Society of Chemical Industry.

Antimicrobial activities of Trichoderma atroviride against common bean seed-borne Macrophomina phaseolina and Rhizoctonia solani

ABSTRACT Common bean (Phaseolus vulgaris L.) is the most consumed legume worldwide, with a commercial value surpassing that of all other legume crops combined. Seed-borne fungi cause at least 10% loss in common bean. Standard blotter (SB) and agar plate (AP) techniques were used to identify seed-borne fungi associated with common bean seeds. Thirty-two fungal species comprising 23 genera were detected. Among the fungal pathogens recovered, Macrophomina phaseolina and Rhizoctonia solani were predominant with a higher recovery using the AP technique than SB technique. Antagonistic activities of six Trichoderma isolates associated with healthy common bean seeds were evaluated against both pathogens, M. phaseolina and R. solani through a dual culture assay. Of them, Trichoderma isolate T22 remarkably suppressed the growth of both pathogens (72.42% and 68%, respectively), 5 days after inoculation. Both pathogens were completely overgrown by T22 mycelia, and sclerotia formation by the two pathogens was lacking compared to the control plates, after 8 days. The T22 isolate was morphologically identified as T. atroviride. The scanning electron microscopy (SEM) confirmed the mycoparasitism of T. atroviride T22 against M. phaseolina and R. solani, resulting in mycelium collapse of both pathogens. A total of nine unique volatile compounds of T. atroviride T22 filtrate were identified by GC-MS technique, representing 75.03% of the total components. Among them, 5-hydroxymethylfurfural (46.11%), and 4 H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (15.66%) were detected as major components, while furfural (3.14%), hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester (2.81%), 1,2-cyclopentanedione (2.79%), and 2-furanmethanol (2.09%) were found to be minor compounds. Our results confirmed that T. atroviride T22 can be used as an effective biocontrol agent against M. phaseolina and R. solani, which are pathogens on common beans and many other crops.

Performance of non-Saccharomyces yeasts isolated from Jiaozi in dough fermentation and steamed bread making

The characteristics of three non-Saccharomyces yeasts, namely, Wickerhamomyces anomalus Y13, Saccharomycopsis fibuligera Y18, and Torulaspora delbrueckii Y22, isolated from Jiaozi in dough fermentation and steamed bread making were investigated and compared with those of Saccharomyces cerevisiae Y10. The maltose levels in the dough fermented by Y13, Y18, and Y22 in the entire fermentation were higher than those in the dough fermented by Y10. The CO2 production kinetics of Y22 was similar to that of Y10, but the total CO2 volume was slightly less. The volume of CO2 produced by Y13 and Y18 was less than 30% of that generated by Y10. The sensory qualities of Y22-prepared steamed bread were similar to those of Y10 and could also be accepted. The degree of whiteness of the steamed bread prepared with Y22 was higher than that produced with Y10. Steamed bread produced with each of the non-Saccharomyces yeasts contained unique volatile compounds, and the highest number of categories of volatile compounds were observed in the product prepared with Y22. The results indicated that non-Saccharomyces yeasts exhibited distinctive characteristics of dough fermentation and showed the potential for applications in dough fermentation and steamed bread making.

A Phylogenetic and Functional Perspective on Volatile Organic Compound Production by Actinobacteria.

Soil microbes produce an immense diversity of metabolites, including volatile organic compounds (VOCs), which can shape the structure and function of microbial communities. VOCs mediate a multitude of microbe-microbe interactions, including antagonism. Despite their importance, the diversity and functional relevance of most microbial volatiles remain uncharacterized. We assembled a taxonomically diverse collection of 48 Actinobacteria isolated from soil and airborne dust and surveyed the VOCs produced by these strains on two different medium types in vitro using gas chromatography-mass spectrometry (GC-MS). We detected 126 distinct VOCs and structurally identified approximately 20% of these compounds, which were predominately C1 to C5 hetero-VOCs, including (oxygenated) alcohols, ketones, esters, and nitrogen- and sulfur-containing compounds. Each strain produced a unique VOC profile. While the most common VOCs were likely by-products of primary metabolism, most of the VOCs were strain specific. We observed a strong taxonomic and phylogenetic signal for VOC profiles, suggesting their role in finer-scale patterns of ecological diversity. Finally, we investigated the functional potential of these VOCs by assessing their effects on growth rates of both pathogenic and nonpathogenic pseudomonad strains. We identified sets of VOCs that correlated with growth inhibition and stimulation, information that may facilitate the development of microbial VOC-based pathogen control strategies. IMPORTANCE Soil microbes produce a diverse array of natural products, including volatile organic compounds (VOCs). Volatile compounds are important molecules in soil habitats, where they mediate interactions between bacteria, fungi, insects, plants, and animals. We measured the VOCs produced by a broad diversity of soil- and dust-dwelling Actinobacteria in vitro. We detected a total of 126 unique volatile compounds, and each strain produced a unique combination of VOCs. While some of the compounds were produced by many strains, most were strain specific. Importantly, VOC profiles were more similar between closely related strains, indicating that evolutionary and ecological processes generate predictable patterns of VOC production. Finally, we observed that actinobacterial VOCs had both stimulatory and inhibitory effects on the growth of bacteria that represent a plant-beneficial symbiont and a plant-pathogenic strain, information that may lead to the development of novel strategies for plant disease prevention.

Assessment of urinary volatile compounds and proteins in the female goat Capra hircus: A pilot study to reveal potential indicators of oestrus.

Urine samples of female goats in pro-oestrus, oestrus and post-oestrus phases were analysed for finding oestrus-specific volatile compounds using gas chromatograph-mass spectrometry (GC-MS), and proteins using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). Fourteen urinary volatile were identified covering all three phases among which four compounds, 1-Tetradecanol, n-Pentadecanol, 3-Methylene tridecane and 2-Ethyl-1-dodecene, were unique to oestrus. Also, oestrus urine contained a 25kDa protein, which was totally absent in pro-oestrus urine, and less-expressed in post-oestrus urine. This protein revealed to be complement C3 fragment. This pilot study, for the first time, reveals the difference in urinary volatile compounds and proteins in the female goat during the different phases of oestrous cycle. The four unique volatile compounds and a 25kDa protein that appeared as oestrus-specific in this study warrant further investigation to consider them as urinary biomarkers of oestrus in goats.

Trichothecium roseum infection promotes ripening of harvested muskmelon fruits and induces the release of specific volatile compound

Pink rot caused by Trichothecium roseum is a major postharvest disease of muskmelon fruit in the northwestern areas of China. The pathogen generally reduced quality of melons and enhanced loss. In this study, T. roseum infected muskmelon (Cucumis melo c v. ‘Jinhongbao’) fruits were used to investigate the effect of infection on respiration rate, ethylene production, basic quality parameters and volatile compounds. The results showed that T. roseum infection increased an earlier ethylene and respiration evolution of the infected fruits. Infected fruit showed an higher weight loss, but lower firmness, total soluble solid (TSS) and ratio of TSS to titratable acid (TA). The amounts of total volatile compounds, aldehydes, alcohols and esters, increased following infection. Among them, heptanal, benzeneacetaldehyde and 4-methyl-2-propyl-1-pentanol were specifically found in the infected fruits. Between the produced volatiles, heptanal and 4-methyl-2-propyl-1-pentanol showed an increase, while benzeneacetaldehyde showed a downward trend over the whole infection period. These results suggested that T. roseum infection promotes muskmelon fruit ripening and quality loss, accelerates release of esters, aldehydes, and alcohols, and produces some unique volatile compounds.

Identification and Characterization of Geranic Acid as a Unique Flavor Compound of Hops ( Humulus lupulus L.) Variety Sorachi Ace.

Hops are natural ingredients used to impart bitterness and flavor to beer. Recently, new varieties of hops have attracted global research attention. The Sorachi Ace variety, in particular, interests many craft brewers. This hop imparts characteristic varietal aromas, including woody, pine-like, citrus, dill-like, and lemongrass-like, to finished beers. Here, we investigated specific flavor compounds derived from Sorachi Ace using selectable one-dimensional or two-dimensional gas chromatography-olfactometry/mass spectrometry and head space-solid phase microextraction-gas chromatography-mass spectrometry. The results showed that a unique volatile compound, geranic acid, was present at a significant level only in the test beer brewed with the Sorachi Ace hop. Furthermore, sensory evaluation techniques revealed that geranic acid has very unique characteristics. This compound is not odor-active but functions as an enhancer for hop-derived terpenoids at subthreshold levels.

Fruit quality and volatile compounds of ‘Jinhong’ plums harvested at different times

The aim of this study was to determine the optimum harvest time of ‘Jinhong’ plums. In 2013, differences in fruit quality and volatile components of ‘Jinhong’ plum at different harvest dates were studied in a field experiment in a plum orchard at Shandong Institute of Pomology. The results showed that fruit weight and soluble sugars, vitamin C, tannin, anthocyanin, and calcium content of the fruit increased with delay in harvest time. The soluble solids and total acid and total flavonoids content first increased and then decreased with delay in harvest time, and the firmness decreased with delay in harvest time. Plums could release unique volatile compounds at different harvest dates, but the rates of volatile compound synthesis decreased as the delay in harvest time increased; an electronic nose was sensitive to changes in volatile compounds in plums harvested at different times. The optimal harvest time of ‘Jinhong’ plums in central Shandong was 20-25 July.

SPME-GC/MS combined with AMDIS analysis of the volatile compounds in fish sauce from different origins

Objective:Identifing the volatile compounds of fish sauce from different origins. Methods:Gas chromatography-mass spectrometry and headspace solid phase microextraction were applied to the examination of the volatile compounds of fish sauce from different origins. Retention index and automatic mass spectral deconvolution system were used to determine the nature of the volatile compound as well. Results:93 kinds of volatile compounds were detected, and the content of esters and aromatic compounds were higher in Guangdong fish sauces than others, and the content of ketones compounds were higher in Thailand fish sauce, and the content of acids and heterocyclic compounds were higher in Vietnamese fish sauce, and the content of aldehydes and alcohols compounds in fish sauce made in laboratory were higher than others. Assignment Validator and Integrator was used for automatic peak alignment of different samples, and satisfactory results were received. 35 kinds of unique volatile compounds and 11 kinds of common volatile compounds were detected in five fish sauce samples. The common volatile compounds were used in principal component analysis, and fish sauces from different origins can be easily separated in the principal component graph. Conclusion:This study identified the characteristics of volatile compounds of fish sauces from different regions, and provided a traceabale method and work flow of using GC-MS to analysis volatile compounds.