To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fer...To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production.展开更多
The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed ...The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process.展开更多
Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma dur...Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time.However,the influence of growth stages on the volatile compounds in Jincheng orange remains unclear.In addition,volatiles originate from fatty acids,most of which are the precursors of volatile substances.On this basis,gas chromatography-mass spectrometry(GC-MS)was performed to elaborate the changes in volatile constituents and fatty acids as precursors.This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages(AF1-AF9).Of those compounds,more than 92.00%of total volatiles and 87.50%of fatty acids were terpenoid and saturated fatty acids,respectively.As shown in the PCA plot,the AF5,AF6,and AF9 stages were confirmed as completely segregated and appeared different.In addition,most of the volatiles and fatty acids first increased at the beginning of the development stage,then decreased from the AF6 development stage,and finally increased at the AF9 maturity stage.Moreover,the highest contents of terpenoid,alcohols,aldehydes,ketones,and saturated fatty acids in Jincheng orange peel oil were d-limonene,linalool,octanal,cyclohexanone,and stearic acid during development stages,respectively.Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil.展开更多
DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched ...DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched egg yolks using comprehensive lipidomics and volatile compound analysis.The results showed that 411 lipids were detected in two egg yolk samples.Among them,148 lipid species,including 48 DHA-containing lipids,were significantly higher in DHA-enriched egg yolks than in Common ones(P<0.05).Furthermore,of the 24 volatile compounds detected,the contents of benzaldehyde,heptanal,hexanal,decanal and 2-nonanone in DHA-enriched egg yolks were significantly higher than in Common egg yolks(P<0.05).The“fishy”smell characteristic of DHAenriched egg yolks was mainly caused by volatile aldehydes,which may be produced through the hydrolysis of lipids in the egg yolk to free fatty acids and further oxidation.Analysis of the correlation network diagram revealed that phospholipids containing docosahexaenoic acid(DHA),linoleic acid,or oleic acid chains were the main contributors to the characteristic flavor of DHA-enriched egg yolks.Overall,this study explored the effect of different lipids on the flavor of DHA-enriched egg yolks and provided a theoretical basis for the production and improvement of DHA-enriched eggs.展开更多
Plant volatile compounds have important physiological and ecological functions.Phenylacetaldehyde(PAld),a volatile phenylpropanoid/benzenoid,accumulates in the leaves of tea(Camellia sinensis)plants grown under contin...Plant volatile compounds have important physiological and ecological functions.Phenylacetaldehyde(PAld),a volatile phenylpropanoid/benzenoid,accumulates in the leaves of tea(Camellia sinensis)plants grown under continuous shading.This study was conducted to determine whether PAld production is correlated with light and to elucidate the physiological functions of PAld in tea plants.Specifically,the upstream mechanism modulating PAld biosynthesis in tea plants under different light conditions as well as the effects of PAld on chloroplast/chlorophyll were investigated.The biosynthesis of PAld was inhibited under light,whereas it was induced in darkness.The structural gene encoding aromatic amino acid aminotransferase 1(CsAAAT1)was expressed at a high level in darkness,consistent with its importance for PAld accumulation.Additionally,the results of a transcriptional activation assay and an electrophoretic mobility shift assay indicated CsAAAT1 expression was slightly activated by phytochrome-interacting factor 3-2(CsPIF3-2),which is a light-responsive transcription factor.Furthermore,PAld might promote the excitation of chlorophyll in dark-treated chloroplasts and mediate electron energy transfer in cells.However,the accumulated PAld can degrade chloroplasts and chlorophyll,with potentially detrimental effects on photosynthesis.Moreover,PAld biosynthesis is inhibited in tea leaves by red and blue light,thereby decreasing the adverse effects of PAld on chloroplasts during daytime.In conclusion,the regulated biosynthesis of PAld in tea plants under light and in darkness leads to chloroplast modifications.The results of this study have expanded our understanding of the biosynthesis and functions of volatile phenylpropanoids/benzenoids in tea leaves.展开更多
Plants respond to environmental stimuli via the release of volatile organic compounds(VOCs),and neighboring plants constantly monitor and respond to these VOCs with great sensitivity and discrimination.This sensing ca...Plants respond to environmental stimuli via the release of volatile organic compounds(VOCs),and neighboring plants constantly monitor and respond to these VOCs with great sensitivity and discrimination.This sensing can trigger increased plant fitness and reduce future plant damage through the priming of their own defenses.The defense mechanism in neighboring plants can either be induced by activation of the regulatory or transcriptional machinery,or it can be delayed by the absorption and storage of VOCs for the generation of an appropriate response later.Despite much research,many key questions remain on the role of VOCs in interplant communication and plant fitness.Here we review recent research on the VOCs induced by biotic(i.e.insects and pathogens)and abiotic(i.e.cold,drought,and salt)stresses,and elucidate the biosynthesis of stress-induced VOCs in tea plants.Our focus is on the role of stress-induced VOCs in complex ecological environments.Particularly,the roles of VOCs under abiotic stress are highlighted.Finally,we discuss pertinent questions and future research directions for advancing our understanding of plant interactions via VOCs.展开更多
This work first describes a simple approach for the untargeted profiling of volatile compounds for distinguishing between white duck down (WDD) and white goose down (WGD) based on resolution-optimized GC-IMS combined ...This work first describes a simple approach for the untargeted profiling of volatile compounds for distinguishing between white duck down (WDD) and white goose down (WGD) based on resolution-optimized GC-IMS combined with optimized chemometric techniques, namely PCA. The detection method for down samples was established by using GC-IMS. Meanwhile, the reason of unpleasant odors caused by WDD was explained on the basis of the characteristic volatile compounds identification. GC-IMS fingerprinting can be considered a revolutionary approach for a truly fully automatable, cost-efficient, and in particular highly sensitive method. A total of 22 compounds were successfully separated and identified through GC-IMS method, and the significant differences in volatile compounds were observed in three parts of WDD and WGD samples. The most characteristic volatile compounds of WGD belong to aldehydes, whereas carboxylic acids from WDD were detected generated by autoxidation reaction. Meanwhile, the main reason of unpleasant odor generation was possibly attributed to the high concentration of volatile carboxylic acids of WDD. Therefore, the constructed model presents a simple and efficient method of analysis and serves as a basis for down processing and quality control.展开更多
Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products.Melon(Pyrus communis)is an aromadense fruit,thus,the evaluation of volatile flavor is crucial to melon-breeding....Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products.Melon(Pyrus communis)is an aromadense fruit,thus,the evaluation of volatile flavor is crucial to melon-breeding.The volatile compounds present in nine varieties of Xinjiang muskmelons were identified and analyzed using the headspace solid-phase microextraction and gas chromatography-mass spectrometry methods.In addition,transcriptomics were used to discover the differential genes in fatty acid degradation pathways.It was found that a total of 170 volatile substances,including 52 alcohols,41 esters,24 aldehydes,32 ketones,14 acids and seven phenols,were identified in the nine melons.Results of PCA showed that 3-nonanol,2-nonanol,bis(2-ethylhexyl)adipate,and 2-methylpropanal contributed more to the flavor of melon.It was verified that high activities of acyl-coenzyme A cholesterol acyltransferase(AAT)promoted the conversion of alcohols to esters,so that the melons have a high content of esters.Four genes of long-chain acyl-CoA synthetase were mainly responsible for the large difference in volatile substances.This practice may further undermine the primary rationale for the breeding and promotion in different cultivars of muskmelon.展开更多
The aroma volatile compounds in Fuji apple were isolated by solid-phase microextraction( SPME),and detected by gas chromatography-mass spectrometry( GC-MS). The results showed that the optimal retention time of the he...The aroma volatile compounds in Fuji apple were isolated by solid-phase microextraction( SPME),and detected by gas chromatography-mass spectrometry( GC-MS). The results showed that the optimal retention time of the heating up of capillary columns was 5 min. Of the seven fibers used in this work,DVB/CAR/PDMS was found to be the most suitable to extract the aroma volatile compounds in Fuji apple. A total number of 43 volatile compounds were identified according to their retention time on capillary columns and their mass spectra,including eleven esters,ten alcohols,ten aldehydes,seven alkenes,two anhydrides,one ketone,one phenol and one ether. This detection method will provide a new foundation for analysis of volatile compounds in apple were identified.展开更多
To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were ana...To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were analyzed and compared,without thyme as control(0.00%,S0).The meaty,fatty,pastoral flavor and spicy were chosen as sensory attributes to evaluate the flavor of the mutton-broth samples.Sensory results were significantly different(P<0.001),with S2 having the optimum overall acceptability.A total of 99 volatile compounds were identified by gas chromatography-mass spectrometry,among which19 compounds were considered as the odor-active compounds according to their odor activity values.Significant changes(P<0.05)appeared in most volatiles in S0 with thyme addition,especially aldehydes.Free fatty acids(FFAs)were also identified,and all of them significantly increased with increased thyme(P<0.05).Correlation analysis of odor-active compounds,FFAs,and sensory attributes through partial least squares regression indicated the important volatiles and FFAs remarkably contributed to the mutton broth samples,and further confirmed that the 0.30%of thyme may be a desirable addition amount for the sensory characteristics of mutton broth.展开更多
[Objectives]This study was conducted to explore the effects of grafting on volatile compounds in bitter gourd fruit.[Methods]The volatile compounds and relative contents of grafted and non-grafted fruit were analyzed ...[Objectives]This study was conducted to explore the effects of grafting on volatile compounds in bitter gourd fruit.[Methods]The volatile compounds and relative contents of grafted and non-grafted fruit were analyzed by headspace solid phase micro-extraction with gas chromatography-mass spectrometry.[Results]There were 59 volatile compounds in Haiyan No.2S,including six unique compounds.There were 58 volatile compounds in Haiyan No.2J,including five unique compounds.[Conclusions]This study provides a scientific basis for further analysis of bitter gourd flavor regulation mediated by grafting.展开更多
A method for optimization of extraction of volatile compounds in Chardonnay wine was developed using headspace-solid phase microextraction (HS-SPME) and gas chromatography coupled with triple quadrupole tandem mass sp...A method for optimization of extraction of volatile compounds in Chardonnay wine was developed using headspace-solid phase microextraction (HS-SPME) and gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS). Optimization of the HS-SPME conditions, temperature (T, °C) and extra-ction time (t, minutes), was carried out using a 2<sup>2</sup> factorial central composite rota- tional design (CCRD). Total area of chromatographic peaks of nineteen compounds was monitored in order to identify the best response and the data was collected on multiple reaction monitoring (MRM) mode. The mathematical model that describes the response surface for the CCRD was validated using the analysis of variance (ANO VA) with 95% of confidence level. This model showed a lack of fit based on mean square pure error ratios for each response, in which F<sub>calculated</sub> was 2.23 higher than F<sub>tabulated</sub>. Even though the models cannot be rigorously used to make quantitative predictions, the coefficients of the model, especially the linear ones, are useful for understanding systematic behaviour of the response values as a function of the factor levels. Multivariate statistical design can be used in optimization of HS-SPME extraction parameters with reduced number of experiments and can be useful in sampling method of volatile compounds of Chardonnay wines analysis by CG-MS/MS. The optimal condition achieved in this method was 30°C and 45 minutes of extraction.展开更多
The freshness and quality indices of whiting (Merlangius merlangus) influenced by a large number of chemical volatile compounds, are here analyzed in order to select the most relevant compounds as predictors for these...The freshness and quality indices of whiting (Merlangius merlangus) influenced by a large number of chemical volatile compounds, are here analyzed in order to select the most relevant compounds as predictors for these indices. The selection process was performed by means of recent statistical variable selection methods, namely robust model-free feature screening, based on quantile correlation and composite quantile correlation. On the one hand, compounds 2-Methyl-1-butanol, 3-Methyl-1-butanol, Ethanol, Trimethylamine, 3-Methyl butanal, 2-Methyl-1-propanol, Ethylacetate, 1-Butanol and 2,3-Butanedione were identified as major predictors for the freshness index and on the other hand, compounds 3-Methyl-1-butanol, 2-Methyl-1- butanol, Ethanol, 3-Methyl butanal, 3-Hydroxy-2-butanone, 1-Butanol, 2,3-Butane- dione, 3-Pentanol, 3-Pentanone and 2-Methyl-1-propanol were identified as major predictors for the quality index.展开更多
In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) fol...In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). The optimum conditions for extracting the volatiles from TS were achieved with the experimental parameters including the use of a 65 μm polydimethylsiloxane/divinyl benzene (PDMS/DVB) fibre, an extraction temperature of 40℃ and an extraction time of 30 min. Under these conditions, 56 volatile compounds were separated and 53 were identified by GC-MS. Among them, 21 sulfide compounds (42.146%) and 27 terpenes(55.984%) were found to be the major components. The sample was analyzed by GC-O and 26 elutes were sniffed and their sensory descriptions evaluated by an odor panelists. Analysis of the data indicated, two compounds cis and trans isomers of 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene were major contributors to the characteristic aroma of TS.展开更多
Chili sauce shrimp paste (CSSP) is an exotic traditional sauce prepared using mainly fresh chili and shrimp paste well known as sambal terasi (Indonesia) and sambal belacan (Malaysia and Brunei). This study aims to ev...Chili sauce shrimp paste (CSSP) is an exotic traditional sauce prepared using mainly fresh chili and shrimp paste well known as sambal terasi (Indonesia) and sambal belacan (Malaysia and Brunei). This study aims to evaluate CSSP from different regions in Indonesia on physiochemical properties, volatile compounds, and sensory evaluation. Evaluation in free amino acid (FAA) and volatile compounds were analyzed using HPLC and GC-MS. CSSP had no significant (p > 0.05) on proximate (except for moisture), salinity, pH, microbial counts and the redness index (a*/b*) compared to control. The identified volatiles can be grouped into hydrocarbon, carbonyl, sulfur, alcohol, nitrogen, fatty acid, and ester compounds. The CSSP A, B, C, D, and E (control) contained 9, 21, 12, 29, and 6 volatile compounds respectively. The total FAA ranged from 44.32 to 67.03 g/100 g, and histidine (his) was found as the most abundant in each CSSP. The rheological properties (yield stress, viscosity, and consistency) of CSSP and control values were significantly, except for CSSP B. The intensities perceived of saltiness, sweetness, and bitterness were greatly varied among CSSP. Although there is no correlation between sweetness and bitterness this is indicated by the negative correlation.展开更多
4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some teas.However,its biosynthesis and metabolism in tea plants are...4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some teas.However,its biosynthesis and metabolism in tea plants are still unknown.Here,HDMF glucoside was unambiguously identified as a native metabolite in tea plants.A novel glucosyltransferase UGT74AF3a and its allelic protein UGT74AF3b specifically catalyzed the glucosylation of HDMF and the commercially important structural homologues 2(or 5)-ethyl-4-hydroxy-5(or 2)-methylfuran-3(2H)-one(EHMF)and 4-hydroxy-5-methylfuran-3(2H)-one(HMF)to their correspondingβ-D-glucosides.Site-directed mutagenesis of UGT74AF3b to introduce a single A456V mutation resulted in improved HDMF and EHMF glucosylation activity and affected the sugar donor preference compared with that of the wild-type control enzyme.The accumulation of HDMF glucoside was consistent with the transcript levels of UGT74AF3 in different tea cultivars.In addition,transient UGT74AF3a overexpression in tobacco significantly increased the HDMF glucoside contents,and downregulation of UGT74AF3 transcripts in tea leaves significantly reduced the concentration of HDMF glucoside compared with the levels in the controls.The identification of HDMF glucoside in the tea plant and the discovery of a novel-specific UDP-glucose:HDMF glucosyltransferase in tea plants provide the foundation for improvement of tea flavor and the biotechnological production of HDMF glucoside.展开更多
Volatile compounds in fresh and fermented sweet potato tips at 0, 10, 20, 30, and 40 d during fermentation were investigated. A new parameter named "relative odor activity value (ROAV)" was applied in evalua...Volatile compounds in fresh and fermented sweet potato tips at 0, 10, 20, 30, and 40 d during fermentation were investigated. A new parameter named "relative odor activity value (ROAV)" was applied in evaluating the contributions of volatile compounds to flavor, considering odor threshold. The results showed that volatile compounds could be clustered in the following chemical families: alkenes (most of them were sesquiterpene), alcohols, aldehydes, ketones, and esters in decreasing order. During fermentation, the concentrations of alkenes and ketones were increased and then decreased continuously. Alcohols and esters were increased; while the concentrations of aldehydes decreased. Interestingly, fermenting processes (0-20 d) may contribute to the increase of alkenes and ketones. Major compounds that were identified in all samples include α- and a-caryophyllene, a- and ?-elemene, and a-cubebene (in decreasing order). The changes of their concentrations during fermentation were the same as that of alkenes. Caryophyllene was abundant in all of the samples examined. It has anti-tumour, anti-inflammatory and anti-pests activities. It can mediate interactions among plant, herbivores and their natural enemies. a- and ?-elemene, which have been used as antitumor drugs, have not been reported previously as volatiles from sweet potato tips. a-cubebene with antioxidant activity can be used as natural preservatives in food and/or by the pharmaceutical industry.展开更多
The effect of the inclusion of chestnut in pigs finishing diet on volatile compounds of dry-cured Celta ham was studied.Twelve hams of each type(from three different pigs finishing diets:concentrate(CO),mixed(MI)and c...The effect of the inclusion of chestnut in pigs finishing diet on volatile compounds of dry-cured Celta ham was studied.Twelve hams of each type(from three different pigs finishing diets:concentrate(CO),mixed(MI)and chestnut(CH)) were used.Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry(GC/MS).Thirty-nine volatile compounds were identified in dry-cured Celta ham samples.Most abundant volatiles in ham samples were aldehydes,which represented respectively,53%(CO),51%(MI)and 46%(CH)of the total volatile composition.With the exception of 2-butenal,2-methyl,all aldehydes were affected by feeding system.On the other hand,hydrocarbons n-alkanes were the second major group in the volatile profile of dry-cured Celta hams and represented 28.9,35.7 and 32.4%of the total volatile composition for CO,MI and CH groups,respectively.Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the finishing diet of pigs.Principal component analysis showed a good separation among groups.The discriminant analysis selected eight variables(butanoic acid,hexanal,octanal,nonenal(E),decenal(E),tetradecane,decane trimethyl and pyridine 2-methyl) and calculated two discriminating functions to predict if chestnut has been included in the finishing diet.Thus,it was possible to discriminate between groups fed with finishing diets containing chestnuts in their composition(mixed and chestnut group).展开更多
Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volati...Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volatile aroma compounds and free fatty acid profiles to compare their differences among the yoghurt products. The results showed that there were significant differences (P<0.05, 0.01, or 0.001) and variations in physico-chemical indices, volatile aroma compounds and volatile free fatty acid profiles among the yoghurt brands, which ultimately influence the flavor quality of the product. Acetaldehyde was predominant volatile compound in yoghurts, which followed by acetone, acetoin, diacetyl and ethanol. The level of diacetly was inversely related to titratable acidity, acetaldehyde and ethanoic acid. From ketones with high carbones 2-undecanone and 2-pentadecanone were higher than 2-butanone, 2-nanonane and 2-tridecanone. These ketones are related to fat content of yoghurt. Among short chain free fatty acids, ethanoic (acetic) acid was the most abundant in yoghurts, followed by hexanoic, octanoic and butanoic acids. These differences in detected chemical compositions of volatile compounds and free fatty acids would be applicable to predict flavor, nutritional value, quality control or shelf-life of the commmercial set-type Turkish yoghurts.展开更多
Volatile compounds from the ripened crabapple fruit of six varieties (Red Splendor, Strawberry Parfait, Pink Spire, Radiant, Sparkler, and Flame) were analyzed by the use of the SPME/GC/MS method. The changes in the v...Volatile compounds from the ripened crabapple fruit of six varieties (Red Splendor, Strawberry Parfait, Pink Spire, Radiant, Sparkler, and Flame) were analyzed by the use of the SPME/GC/MS method. The changes in the volatiles between the ripened and upon full maturity fruit states were studied in Red Splendor and Strawberry Parfait. An effort was made to summarize an effective method for searching and identifying new idioplasms containing a particular fruit aroma within Malus. A total of 37 compounds were identified from the sample. The main aroma volatiles of the six varieties of fruit were comprised of 2-hexenal, 3-hexenal, hexanal, 2,4-hexadienal, benzaldehyde, diethyl phthalate. The main volatile compound of the crabapple fruit was 2-hexenal, but the relative content percentages were different (45.37, 21.98, 33.56, 32.21, 38.60, and 45.88%). The aroma components accumulated differently as the fruits ripened. The relative content of aldehydes and esters decreased as alcohols increased after the Red Splendor and Strawberry Parfait fruit ripened. For Red Splendor, the main volatile was still 2-hexenal, but the relative content decreased to 42.89%, and the relative content of alcohols increased by 13.86% as aldehydes and esters declined by 12.16 and 7.18%, respectively. For Strawberry Parfait, the main volatile was changed to cyclohexanol, and the relative content increased to 46.43%, while the relative content of alcohols increased by 49.03% as aldehydes and esters declined by 23.74 and 9.34%, respectively.展开更多
基金supported by Special key project of technological innovation and application development in Yongchuan District,Chongqing(2021yc-cxfz20002)the special funds of central government for guiding local science and technology developmentthe funds for the platform projects of professional technology innovation(CSTC2018ZYCXPT0006).
文摘To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production.
基金supported by National Natural Science Foundation of China(Nos.31871861 and 31501548)The Apicultural Industry Technology System(NCYTI-43-KXJ17)The Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2015-IAR)。
文摘The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process.
基金supported by the Guizhou Provincial Science and Technology Projects,China(ZK[2022]391)the Cultivation Project of National Natural Science Foundation of Guizhou Medical University,China(21NSFCP20).
文摘Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time.However,the influence of growth stages on the volatile compounds in Jincheng orange remains unclear.In addition,volatiles originate from fatty acids,most of which are the precursors of volatile substances.On this basis,gas chromatography-mass spectrometry(GC-MS)was performed to elaborate the changes in volatile constituents and fatty acids as precursors.This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages(AF1-AF9).Of those compounds,more than 92.00%of total volatiles and 87.50%of fatty acids were terpenoid and saturated fatty acids,respectively.As shown in the PCA plot,the AF5,AF6,and AF9 stages were confirmed as completely segregated and appeared different.In addition,most of the volatiles and fatty acids first increased at the beginning of the development stage,then decreased from the AF6 development stage,and finally increased at the AF9 maturity stage.Moreover,the highest contents of terpenoid,alcohols,aldehydes,ketones,and saturated fatty acids in Jincheng orange peel oil were d-limonene,linalool,octanal,cyclohexanone,and stearic acid during development stages,respectively.Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil.
基金supported by the Opening Project of Hubei Key Laboratory of Lipid Chemistry and Nutrition(202106).
文摘DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched egg yolks using comprehensive lipidomics and volatile compound analysis.The results showed that 411 lipids were detected in two egg yolk samples.Among them,148 lipid species,including 48 DHA-containing lipids,were significantly higher in DHA-enriched egg yolks than in Common ones(P<0.05).Furthermore,of the 24 volatile compounds detected,the contents of benzaldehyde,heptanal,hexanal,decanal and 2-nonanone in DHA-enriched egg yolks were significantly higher than in Common egg yolks(P<0.05).The“fishy”smell characteristic of DHAenriched egg yolks was mainly caused by volatile aldehydes,which may be produced through the hydrolysis of lipids in the egg yolk to free fatty acids and further oxidation.Analysis of the correlation network diagram revealed that phospholipids containing docosahexaenoic acid(DHA),linoleic acid,or oleic acid chains were the main contributors to the characteristic flavor of DHA-enriched egg yolks.Overall,this study explored the effect of different lipids on the flavor of DHA-enriched egg yolks and provided a theoretical basis for the production and improvement of DHA-enriched eggs.
基金supported by grants from the National Natural Science Foundation of China(31902074)the Guangdong Basic and Applied Basic Research Foundation(2020A1515010539)+4 种基金the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2020QNRC001)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2022351)the Basic Frontier Science Research Program of Chinese Academy of Sciences(ZDBS-LY-SM032)the Guangdong Provincial Special Fund for Modern Agriculture Industry Technology Innovation Teams(2023KJ120)Guangdong Provincial Department of Science and Technology Rural Science and Technology Commissioner Project(KTP20210351).
文摘Plant volatile compounds have important physiological and ecological functions.Phenylacetaldehyde(PAld),a volatile phenylpropanoid/benzenoid,accumulates in the leaves of tea(Camellia sinensis)plants grown under continuous shading.This study was conducted to determine whether PAld production is correlated with light and to elucidate the physiological functions of PAld in tea plants.Specifically,the upstream mechanism modulating PAld biosynthesis in tea plants under different light conditions as well as the effects of PAld on chloroplast/chlorophyll were investigated.The biosynthesis of PAld was inhibited under light,whereas it was induced in darkness.The structural gene encoding aromatic amino acid aminotransferase 1(CsAAAT1)was expressed at a high level in darkness,consistent with its importance for PAld accumulation.Additionally,the results of a transcriptional activation assay and an electrophoretic mobility shift assay indicated CsAAAT1 expression was slightly activated by phytochrome-interacting factor 3-2(CsPIF3-2),which is a light-responsive transcription factor.Furthermore,PAld might promote the excitation of chlorophyll in dark-treated chloroplasts and mediate electron energy transfer in cells.However,the accumulated PAld can degrade chloroplasts and chlorophyll,with potentially detrimental effects on photosynthesis.Moreover,PAld biosynthesis is inhibited in tea leaves by red and blue light,thereby decreasing the adverse effects of PAld on chloroplasts during daytime.In conclusion,the regulated biosynthesis of PAld in tea plants under light and in darkness leads to chloroplast modifications.The results of this study have expanded our understanding of the biosynthesis and functions of volatile phenylpropanoids/benzenoids in tea leaves.
基金supported by the National Key Research and Development Program of China(2022YFF1003103)the National Natural Science Foundation of China(U22A20499 and 32022076)+1 种基金the Deutsche Forschungsgemeinschaft(DFG SCHW 634/34-1)the China Postdoctoral Science Foundation 2022 M720193。
文摘Plants respond to environmental stimuli via the release of volatile organic compounds(VOCs),and neighboring plants constantly monitor and respond to these VOCs with great sensitivity and discrimination.This sensing can trigger increased plant fitness and reduce future plant damage through the priming of their own defenses.The defense mechanism in neighboring plants can either be induced by activation of the regulatory or transcriptional machinery,or it can be delayed by the absorption and storage of VOCs for the generation of an appropriate response later.Despite much research,many key questions remain on the role of VOCs in interplant communication and plant fitness.Here we review recent research on the VOCs induced by biotic(i.e.insects and pathogens)and abiotic(i.e.cold,drought,and salt)stresses,and elucidate the biosynthesis of stress-induced VOCs in tea plants.Our focus is on the role of stress-induced VOCs in complex ecological environments.Particularly,the roles of VOCs under abiotic stress are highlighted.Finally,we discuss pertinent questions and future research directions for advancing our understanding of plant interactions via VOCs.
文摘This work first describes a simple approach for the untargeted profiling of volatile compounds for distinguishing between white duck down (WDD) and white goose down (WGD) based on resolution-optimized GC-IMS combined with optimized chemometric techniques, namely PCA. The detection method for down samples was established by using GC-IMS. Meanwhile, the reason of unpleasant odors caused by WDD was explained on the basis of the characteristic volatile compounds identification. GC-IMS fingerprinting can be considered a revolutionary approach for a truly fully automatable, cost-efficient, and in particular highly sensitive method. A total of 22 compounds were successfully separated and identified through GC-IMS method, and the significant differences in volatile compounds were observed in three parts of WDD and WGD samples. The most characteristic volatile compounds of WGD belong to aldehydes, whereas carboxylic acids from WDD were detected generated by autoxidation reaction. Meanwhile, the main reason of unpleasant odor generation was possibly attributed to the high concentration of volatile carboxylic acids of WDD. Therefore, the constructed model presents a simple and efficient method of analysis and serves as a basis for down processing and quality control.
基金This study was funded by China Agriculture Research System of Modern Agro-industry Technology Research(CARS-25)public welfare scientific research institutes of Xinjiang(KY2021118 and KY2020108)China Postdoctor(No.299580).
文摘Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products.Melon(Pyrus communis)is an aromadense fruit,thus,the evaluation of volatile flavor is crucial to melon-breeding.The volatile compounds present in nine varieties of Xinjiang muskmelons were identified and analyzed using the headspace solid-phase microextraction and gas chromatography-mass spectrometry methods.In addition,transcriptomics were used to discover the differential genes in fatty acid degradation pathways.It was found that a total of 170 volatile substances,including 52 alcohols,41 esters,24 aldehydes,32 ketones,14 acids and seven phenols,were identified in the nine melons.Results of PCA showed that 3-nonanol,2-nonanol,bis(2-ethylhexyl)adipate,and 2-methylpropanal contributed more to the flavor of melon.It was verified that high activities of acyl-coenzyme A cholesterol acyltransferase(AAT)promoted the conversion of alcohols to esters,so that the melons have a high content of esters.Four genes of long-chain acyl-CoA synthetase were mainly responsible for the large difference in volatile substances.This practice may further undermine the primary rationale for the breeding and promotion in different cultivars of muskmelon.
基金Supported by Innovative Projects of Hebei Academy of Agriculture and Forestry Sciences (2019-3-4-5)。
文摘The aroma volatile compounds in Fuji apple were isolated by solid-phase microextraction( SPME),and detected by gas chromatography-mass spectrometry( GC-MS). The results showed that the optimal retention time of the heating up of capillary columns was 5 min. Of the seven fibers used in this work,DVB/CAR/PDMS was found to be the most suitable to extract the aroma volatile compounds in Fuji apple. A total number of 43 volatile compounds were identified according to their retention time on capillary columns and their mass spectra,including eleven esters,ten alcohols,ten aldehydes,seven alkenes,two anhydrides,one ketone,one phenol and one ether. This detection method will provide a new foundation for analysis of volatile compounds in apple were identified.
基金supported by the National key research and development program(grant number 2016YFD0400705)。
文摘To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were analyzed and compared,without thyme as control(0.00%,S0).The meaty,fatty,pastoral flavor and spicy were chosen as sensory attributes to evaluate the flavor of the mutton-broth samples.Sensory results were significantly different(P<0.001),with S2 having the optimum overall acceptability.A total of 99 volatile compounds were identified by gas chromatography-mass spectrometry,among which19 compounds were considered as the odor-active compounds according to their odor activity values.Significant changes(P<0.05)appeared in most volatiles in S0 with thyme addition,especially aldehydes.Free fatty acids(FFAs)were also identified,and all of them significantly increased with increased thyme(P<0.05).Correlation analysis of odor-active compounds,FFAs,and sensory attributes through partial least squares regression indicated the important volatiles and FFAs remarkably contributed to the mutton broth samples,and further confirmed that the 0.30%of thyme may be a desirable addition amount for the sensory characteristics of mutton broth.
基金Supported by Hainan Science and Technology Project(No.ZDYF2020229)Scientific Research Project of Key Laboratory for Quality Regulation of Tropical Horticultural Plants of Hainan Province(No.HNZDSYS(YY)-03)。
文摘[Objectives]This study was conducted to explore the effects of grafting on volatile compounds in bitter gourd fruit.[Methods]The volatile compounds and relative contents of grafted and non-grafted fruit were analyzed by headspace solid phase micro-extraction with gas chromatography-mass spectrometry.[Results]There were 59 volatile compounds in Haiyan No.2S,including six unique compounds.There were 58 volatile compounds in Haiyan No.2J,including five unique compounds.[Conclusions]This study provides a scientific basis for further analysis of bitter gourd flavor regulation mediated by grafting.
文摘A method for optimization of extraction of volatile compounds in Chardonnay wine was developed using headspace-solid phase microextraction (HS-SPME) and gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS). Optimization of the HS-SPME conditions, temperature (T, °C) and extra-ction time (t, minutes), was carried out using a 2<sup>2</sup> factorial central composite rota- tional design (CCRD). Total area of chromatographic peaks of nineteen compounds was monitored in order to identify the best response and the data was collected on multiple reaction monitoring (MRM) mode. The mathematical model that describes the response surface for the CCRD was validated using the analysis of variance (ANO VA) with 95% of confidence level. This model showed a lack of fit based on mean square pure error ratios for each response, in which F<sub>calculated</sub> was 2.23 higher than F<sub>tabulated</sub>. Even though the models cannot be rigorously used to make quantitative predictions, the coefficients of the model, especially the linear ones, are useful for understanding systematic behaviour of the response values as a function of the factor levels. Multivariate statistical design can be used in optimization of HS-SPME extraction parameters with reduced number of experiments and can be useful in sampling method of volatile compounds of Chardonnay wines analysis by CG-MS/MS. The optimal condition achieved in this method was 30°C and 45 minutes of extraction.
文摘The freshness and quality indices of whiting (Merlangius merlangus) influenced by a large number of chemical volatile compounds, are here analyzed in order to select the most relevant compounds as predictors for these indices. The selection process was performed by means of recent statistical variable selection methods, namely robust model-free feature screening, based on quantile correlation and composite quantile correlation. On the one hand, compounds 2-Methyl-1-butanol, 3-Methyl-1-butanol, Ethanol, Trimethylamine, 3-Methyl butanal, 2-Methyl-1-propanol, Ethylacetate, 1-Butanol and 2,3-Butanedione were identified as major predictors for the freshness index and on the other hand, compounds 3-Methyl-1-butanol, 2-Methyl-1- butanol, Ethanol, 3-Methyl butanal, 3-Hydroxy-2-butanone, 1-Butanol, 2,3-Butane- dione, 3-Pentanol, 3-Pentanone and 2-Methyl-1-propanol were identified as major predictors for the quality index.
文摘In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). The optimum conditions for extracting the volatiles from TS were achieved with the experimental parameters including the use of a 65 μm polydimethylsiloxane/divinyl benzene (PDMS/DVB) fibre, an extraction temperature of 40℃ and an extraction time of 30 min. Under these conditions, 56 volatile compounds were separated and 53 were identified by GC-MS. Among them, 21 sulfide compounds (42.146%) and 27 terpenes(55.984%) were found to be the major components. The sample was analyzed by GC-O and 26 elutes were sniffed and their sensory descriptions evaluated by an odor panelists. Analysis of the data indicated, two compounds cis and trans isomers of 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene were major contributors to the characteristic aroma of TS.
文摘Chili sauce shrimp paste (CSSP) is an exotic traditional sauce prepared using mainly fresh chili and shrimp paste well known as sambal terasi (Indonesia) and sambal belacan (Malaysia and Brunei). This study aims to evaluate CSSP from different regions in Indonesia on physiochemical properties, volatile compounds, and sensory evaluation. Evaluation in free amino acid (FAA) and volatile compounds were analyzed using HPLC and GC-MS. CSSP had no significant (p > 0.05) on proximate (except for moisture), salinity, pH, microbial counts and the redness index (a*/b*) compared to control. The identified volatiles can be grouped into hydrocarbon, carbonyl, sulfur, alcohol, nitrogen, fatty acid, and ester compounds. The CSSP A, B, C, D, and E (control) contained 9, 21, 12, 29, and 6 volatile compounds respectively. The total FAA ranged from 44.32 to 67.03 g/100 g, and histidine (his) was found as the most abundant in each CSSP. The rheological properties (yield stress, viscosity, and consistency) of CSSP and control values were significantly, except for CSSP B. The intensities perceived of saltiness, sweetness, and bitterness were greatly varied among CSSP. Although there is no correlation between sweetness and bitterness this is indicated by the negative correlation.
基金supported by the National Natural Science Foundation of China(31961133030,31870678)National Key Research and Development Program of China(2018YFD1000601)Science Fund for Distinguished Young Scientists of Anhui Province(1908085J12).
文摘4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some teas.However,its biosynthesis and metabolism in tea plants are still unknown.Here,HDMF glucoside was unambiguously identified as a native metabolite in tea plants.A novel glucosyltransferase UGT74AF3a and its allelic protein UGT74AF3b specifically catalyzed the glucosylation of HDMF and the commercially important structural homologues 2(or 5)-ethyl-4-hydroxy-5(or 2)-methylfuran-3(2H)-one(EHMF)and 4-hydroxy-5-methylfuran-3(2H)-one(HMF)to their correspondingβ-D-glucosides.Site-directed mutagenesis of UGT74AF3b to introduce a single A456V mutation resulted in improved HDMF and EHMF glucosylation activity and affected the sugar donor preference compared with that of the wild-type control enzyme.The accumulation of HDMF glucoside was consistent with the transcript levels of UGT74AF3 in different tea cultivars.In addition,transient UGT74AF3a overexpression in tobacco significantly increased the HDMF glucoside contents,and downregulation of UGT74AF3 transcripts in tea leaves significantly reduced the concentration of HDMF glucoside compared with the levels in the controls.The identification of HDMF glucoside in the tea plant and the discovery of a novel-specific UDP-glucose:HDMF glucosyltransferase in tea plants provide the foundation for improvement of tea flavor and the biotechnological production of HDMF glucoside.
基金supported by the Inde-pendent Innovation of Agricultural Sciences in Jiangsu Province, China (CX [09]628)
文摘Volatile compounds in fresh and fermented sweet potato tips at 0, 10, 20, 30, and 40 d during fermentation were investigated. A new parameter named "relative odor activity value (ROAV)" was applied in evaluating the contributions of volatile compounds to flavor, considering odor threshold. The results showed that volatile compounds could be clustered in the following chemical families: alkenes (most of them were sesquiterpene), alcohols, aldehydes, ketones, and esters in decreasing order. During fermentation, the concentrations of alkenes and ketones were increased and then decreased continuously. Alcohols and esters were increased; while the concentrations of aldehydes decreased. Interestingly, fermenting processes (0-20 d) may contribute to the increase of alkenes and ketones. Major compounds that were identified in all samples include α- and a-caryophyllene, a- and ?-elemene, and a-cubebene (in decreasing order). The changes of their concentrations during fermentation were the same as that of alkenes. Caryophyllene was abundant in all of the samples examined. It has anti-tumour, anti-inflammatory and anti-pests activities. It can mediate interactions among plant, herbivores and their natural enemies. a- and ?-elemene, which have been used as antitumor drugs, have not been reported previously as volatiles from sweet potato tips. a-cubebene with antioxidant activity can be used as natural preservatives in food and/or by the pharmaceutical industry.
基金financially supported by the Spanish Ministry of Science and Innovation(AGL2008-05274-C02-01/ALI)
文摘The effect of the inclusion of chestnut in pigs finishing diet on volatile compounds of dry-cured Celta ham was studied.Twelve hams of each type(from three different pigs finishing diets:concentrate(CO),mixed(MI)and chestnut(CH)) were used.Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry(GC/MS).Thirty-nine volatile compounds were identified in dry-cured Celta ham samples.Most abundant volatiles in ham samples were aldehydes,which represented respectively,53%(CO),51%(MI)and 46%(CH)of the total volatile composition.With the exception of 2-butenal,2-methyl,all aldehydes were affected by feeding system.On the other hand,hydrocarbons n-alkanes were the second major group in the volatile profile of dry-cured Celta hams and represented 28.9,35.7 and 32.4%of the total volatile composition for CO,MI and CH groups,respectively.Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the finishing diet of pigs.Principal component analysis showed a good separation among groups.The discriminant analysis selected eight variables(butanoic acid,hexanal,octanal,nonenal(E),decenal(E),tetradecane,decane trimethyl and pyridine 2-methyl) and calculated two discriminating functions to predict if chestnut has been included in the finishing diet.Thus,it was possible to discriminate between groups fed with finishing diets containing chestnuts in their composition(mixed and chestnut group).
文摘Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volatile aroma compounds and free fatty acid profiles to compare their differences among the yoghurt products. The results showed that there were significant differences (P<0.05, 0.01, or 0.001) and variations in physico-chemical indices, volatile aroma compounds and volatile free fatty acid profiles among the yoghurt brands, which ultimately influence the flavor quality of the product. Acetaldehyde was predominant volatile compound in yoghurts, which followed by acetone, acetoin, diacetyl and ethanol. The level of diacetly was inversely related to titratable acidity, acetaldehyde and ethanoic acid. From ketones with high carbones 2-undecanone and 2-pentadecanone were higher than 2-butanone, 2-nanonane and 2-tridecanone. These ketones are related to fat content of yoghurt. Among short chain free fatty acids, ethanoic (acetic) acid was the most abundant in yoghurts, followed by hexanoic, octanoic and butanoic acids. These differences in detected chemical compositions of volatile compounds and free fatty acids would be applicable to predict flavor, nutritional value, quality control or shelf-life of the commmercial set-type Turkish yoghurts.
基金the program of Technology Development Program of Shandong Province, China(2007GG20009013)
文摘Volatile compounds from the ripened crabapple fruit of six varieties (Red Splendor, Strawberry Parfait, Pink Spire, Radiant, Sparkler, and Flame) were analyzed by the use of the SPME/GC/MS method. The changes in the volatiles between the ripened and upon full maturity fruit states were studied in Red Splendor and Strawberry Parfait. An effort was made to summarize an effective method for searching and identifying new idioplasms containing a particular fruit aroma within Malus. A total of 37 compounds were identified from the sample. The main aroma volatiles of the six varieties of fruit were comprised of 2-hexenal, 3-hexenal, hexanal, 2,4-hexadienal, benzaldehyde, diethyl phthalate. The main volatile compound of the crabapple fruit was 2-hexenal, but the relative content percentages were different (45.37, 21.98, 33.56, 32.21, 38.60, and 45.88%). The aroma components accumulated differently as the fruits ripened. The relative content of aldehydes and esters decreased as alcohols increased after the Red Splendor and Strawberry Parfait fruit ripened. For Red Splendor, the main volatile was still 2-hexenal, but the relative content decreased to 42.89%, and the relative content of alcohols increased by 13.86% as aldehydes and esters declined by 12.16 and 7.18%, respectively. For Strawberry Parfait, the main volatile was changed to cyclohexanol, and the relative content increased to 46.43%, while the relative content of alcohols increased by 49.03% as aldehydes and esters declined by 23.74 and 9.34%, respectively.
