SPME-GC-MS分析不同产地干黄芪中挥发性风味成分

为了研究不同产地干黄芪的香气成分,采用固相微萃取法分别提取产自山西、内蒙古和甘肃的干黄芪香气成分,提取物经过气-质联用分析仪分析,共鉴定出117种挥发性成分,其中包括烯烃类21种、醇类15种、酸类15种、醛类14种、其他类14种、酮类14种、杂环类8种、酯类10种和酚类6种。内蒙古黄芪香气成分种类最多,为91种,总相对含量为79.49%;其次是山西黄芪,鉴定出75种香气成分,总相对含量为82.49%;香气成分种类最少是甘肃黄芪,为72种,总相对含量为89.64%。在不同产地中鉴定出43种共有成分,其中正己醛、苯甲醛、1-戊醇、3-辛烯-2-酮、丁香酚、榄香素、2-丁基呋喃、2-正戊基呋喃是干黄芪特征香气成分。不同产地的干黄芪香气成分在种类和含量上也有所不同。     

Volatile organic compounds associated with milk spoilage by psychrotrophic bacteria

The volatile organic compounds of milk contaminated with psychrotrophic bacteria were studied by HS‐SPME and GC/MS. Pseudomonas fluorescens PS14, Pseudomonas fragi PS55, Pseudomonas mosselii PS39, Pseudomonas rhodesiae PS62 and Serratia marcescens S92 were inoculated in sterilised milk (2.5% fat) stored at either 5 °C or 10 °C. A total of 47 volatile organic compounds (VOCs) belonging to seven chemical groups were identified in the spoiled milk. Volatile organic compound patterns peculiar to the inoculate bacterial strains were highlighted. 3‐Methylbutan‐1‐ol, 2 methylpropan‐1‐ol, 3‐hydroxybutan‐2‐one, butan‐2,3‐dione, butanoic and hexanoic acids were revealed as potential chemical spoilage indexes of milk spoilage due to the activity of the five psychrotrophic strains studied.     

固相微萃取/气相色谱-质谱联用分析麦芽挥发性风味物质组成

利用固相微萃取与气相色谱-质谱联用分析了酿造大麦Sabastian中的挥发性风味物质组成,共分析鉴定出31种挥发性物质,其中对酿造麦芽风味贡献较大的化合物有:醛类化合物13种占总峰面积的74.65%,醇类化合物7种占总峰面积的4.63%,酮类2种占总峰面积的0.18%,酸类一种占总峰面积的0.62%,其它类化合物8种占总峰面积的11.84%;含量较高的成分为异戊醛、2-甲基丁醛和正己醛,其峰面积相对百分比分别达到26.31%、24.69%和12.87%,搞清了酿造大麦嗅感物质的组成。     

Determination of volatile compounds and quality parameters of traditional Istrian dry-cured ham

The aim of this work was to determine the characteristics of Istrian dry-cured ham by instrumental methods and sensory analysis. The aroma-active compounds of Istrian dry-cured ham from 2010 and 2012 were investigated by using headspace-solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). Samples of biceps femoris were also evaluated by measuring physical and chemical characteristics. 92 volatile aroma compounds of Istrian dry-cured ham were found. Volatile compounds belonged to several chemical groups: aldehydes (51.4; 51.3%), terpenes (16.5; 16.4%), alcohols (15.5; 13.2%), ketones (8.6; 7.4%), alkanes (3.8; 5.7%), esters (1.3; 1.6%), aromatic hydrocarbons (0.8; 3.9%) and acids (0.6; 0.9%). Principal component analysis (PCA) showed that fat content, tenderness and melting texture were positively correlated. Terpenes were strongly correlated with flavour of added spices. Sweet taste and the presence of esters were positively correlated as well as negative odour, raw meat flavour and water content.     

Evaluation of pre-rigor injection of beef with proteases on cooked meat volatile profile after 1day and 21days post-mortem storage

This research was carried out to determine the effects of pre-rigor injection of beef semimembranosus muscle with nine proteases from plant and microbial sources, on the volatile profile of cooked beef after 1 day and 21 days post-mortem (PM) storage using Solid-phase microextraction gas chromatography mass spectrometry analysis. A total of 23 aldehydes, 5 ketones, 3 furans, 8 nitrogen and sulphur compounds, 4 alkanes, 7 alcohols and 6 terpenes were detected. Eleven volatile compounds characteristic of ginger flavour were detected in zingibain-treated meat. Benzaldehyde significantly increased (p<0.05) only in kiwifruit juice (KJ), fungal 31 protease and Asparagus protease (ASP) treated samples from 1day to 21days PM storage. A significant increase (p<0.05) in 3-methylbutanal was observed in KJ, bacterial and fungal protease treated samples at 21days PM storage. Treatments with bromelain, papain, ASP, actinidin, and KJ (except KJ 21days) proteases resulted in flavour profiles closer to that of the control beef sample.     

Comparison of volatile compounds in yoghurts made from cows’, buffaloes’, ewes’ and goats’ milks

The composition of the volatile fraction of yoghurts made from cows’, buffaloes’, ewes’ and goats’ milks was investigated during the 28 days of storage at 4 °C using solid‐phase microextraction technique (SPME) and gas chromatography coupled to mass spectrometry analysis (GC/MS). A total of 34 volatile compounds were identified in yoghurts during their storage at 4 °C, including aldehydes, ketones, alcohols, esters, acids, terpenes, hydrocarbons and sulphur compounds. In this study, acetaldehyde, diacetyl and acetoin, considered as the major compounds of yoghurt, were detected in all yoghurts.     

Evolution of the volatile compounds of ripened sausages as a function of both storage time and composition of packaging atmosphere

An experimental investigation was carried out to study the evolution of the volatile compounds of ripened sausages as a function of both storage time (time) and composition of packaging atmosphere (MAP). Ripened sausages, prepared at an industrial plant, were packed applying three different atmosphere compositions and were stored for three months. The obtained data evinced that the evolution of the volatile compounds was significantly related to the variable time more than to the variable MAP. The main volatile compounds were those derived from spices. Among them, Δ³-carene was the most abundant and a significant decrease was observed during storage (p < 0.05). The volatile compounds derived from lipid autoxidation showed generally a significant increase during storage, suggesting the raise of lipid oxidation also at low oxygen concentration. Moreover, octanal and nonanal were significantly influenced by the atmosphere composition, with the highest values in samples packed at the lowest CO₂ concentration.     

Use of digital aroma technology and SPME GC-MS to compare volatile compounds produced by bacteria isolated from processed poultry

Digital aroma technology, solid-phase micro-extraction (SPME) and gas chromatographic mass spectral (GC-MS) analysis of the headspace volatile organic compounds were used to compare bacterial species important for food safety and common to biofilms in the poultry processing environment. The instrument for digital aroma technology, called the electronic nose, measured changes in resistance of polymer sensors caused by volatile gases from the headspace of samples. Graphical output by the Sammon mapping technique produced patterns of differences or similarities among the samples. Artificial neural network software was used to model groups of samples and classify subsequent unknowns. Compounds isolated from the headspace of sealed cultures using polydimethylsiloxane SPME fibres and identified by GC-MS analyses were predominantly alcohols and indole. These qualitative profiles were repetitive for specific organisms in relation to purity and repeatability of the cultures, differed by species and were used as objective standards to compare the graphical outputs of the electronic nose. © 1998 Society of Chemical Industry.     

Dynamics of volatile and non-volatile compounds in cocoa (Theobroma cacao L.) during fermentation and drying processes using principal components analysis

Different volatile and non-volatile compounds produced during the fermentation-drying process are considered as indicatives of cocoa beans quality. We found thirty-nine different compounds identified by SPME-HS/GC-MS and related to the desirable notes and off-flavor that have been reported. Volatile and non-volatile compounds were associated with acidity and changes of pH, such as acetic and lactic acid. Using the principal component analysis (PCA), relations between compounds and fermentation and drying day were associated with dynamics of these compounds. The identification of principal compound produced during the fermentation and drying processes can be helpful in searching for off-flavor indicator and as a fermentation index, such as isobutyric, isovaleric and propionic acids. Oxidation of 3-methyl-1-butanol-to-3-methyl-1-butanol acetate can be of use in evaluating the degree of fermentation. At drying, the compounds with the highest levels were acetic and isobutyric acid, ethyl and 3-methyl-1-butanol acetate, pentanal and 2,3-pentanedione, and 1,3-butanediol and 2,3-butanediol. Therefore, acetic acid and isobutyric acid, due to their high levels and their low threshold value could play an important role in the aromatic quality of cacao drying.     

The effect of different dietary treatments on volatile organic compounds and aromatic characteristics of buffalo Mozzarella cheese

The objective of this study was to evaluate the effect of two dietary treatments, ryegrass hay (RH) and wrapped ryegrass silage (WRS) on the volatile organic compounds (VOCs) of buffalo Mozzarella cheese. The primary data were collected from 40 female buffaloes. Twenty animals were fed RH, and other twenty received WRS. Volatile organic compounds were identified using a mass selective detector after extraction with a ‘purge and trap’ system and a gas chromatographic analysis. Our results showed differences in the aromatic profile of Mozzarella cheese samples obtained from buffaloes receiving different feed. In particular, 5 VOCs allowed the discrimination between cheese samples.     

The volatile fraction profiling of fresh tomatoes and triple concentrate tomato pastes as parameter for the determination of geographical origin

Two unsupervised pattern recognition techniques such as stepwise linear discriminant analysis (SLDA) and Soft Independent Modeling of Class Analogy (SIMCA) were used to classify tomato samples in categories corresponding to the cultivation areas. The same approach was used for triple concentrated pastes for discrimination between two different Italian production areas. Accordingly, HS-SPME-GC-MS with 85 ??m carboxen/polydimethylsiloxane fiber was used for the determination of the volatile fraction in tomatoes and triple concentrate tomato pastes samples. Ethyl isobututanoate was used as internal standard for semiquantitative analysis and the concentration data (??g/kg) of 38 compounds for tomatoes and of 32 compounds for triple concentrates were used in following chemometric analysis. Sixteen and three variables were selected by forward stepwise LDA for tomatoes and pastes, respectively. SLDA and SIMCA models showed respectively 96% and 94% in term of prediction ability for tomatoes. The two supervised techniques provided 100% and 97% in prediction of the production areas of tomato pastes, respectively.     

Volatile composition and sensory characteristics of Chardonnay wines treated with American and Hungarian oak chips

Toasted or non-toasted chips of oak woods of different geographical provenances were macerated in Chardonnay wines (4 g/l) during a period of 25 days. Oak lactones were detected in significant quantities in wines treated with American oak. Only trace amounts of oak lactones were detected in the wines treated with Hungarian oak. Toasting of the oaks increased the quantities of the compounds derived from the thermal degradation of lignin: vanillin, eugenol, guaiacol and its derivatives and the pyrolysis of cellulose and hemicellulose: furfural and 5-methyl furfural, and decreased the concentrations of the two isomers of oak lactones. The concentrations of the majority of the volatile compounds did not present statistically significant differences between 15 and 25 days. However, the wines preferred by the tasters and with maximum intensity of the sensory attributes acquired were those treated with oak chips for 25 days. Chemical and sensorial analyses of wines revealed that the effect of the toasting of oak chips on wine characteristics was greater than the type of oak used. All wines studied were positively evaluated by the panellists.     

Differentiation of monofloral citrus,rosemary, eucalyptus,lavender, thyme and heather honeys based on volatile composition and sensory descriptive analysis

The volatile profiles of 49 Spanish honey samples of different botanical origins were obtained by means of gas chromatography–mass spectrometry and sensory analysis. Citrus honeys were characterised by higher amounts of linalool derivatives, limonyl alcohol, sinensal isomers, and α-4-dimethyl-3-cyclohexene-1-acetaldehyde, together with fresh fruit and citric aromas; eucalyptus honeys had hydroxyketones (acetoin, 5-hydroxy-2,7-dimethyl-4-octanone), p-cymene derivatives, 3-caren-2-ol and spathulenol, cheese and hay aromas; lavender honeys had hexanal, nerolidol oxide, coumarin, important concentrations of hexanol and hotrienol and sensorial attributes, including balsamic and aromatic herb aromas; finally, heather honeys were characterised by high contents of benzene and phenolic compounds and ripe fruit and spicy aromas. Some of these compounds and sensory attributes were only found in honeys from a specific floral source and could thus be of interest for use as markers of their botanical origin.     

Proteinase-producing halophilic lactic acid bacteria isolated from fish sauce fermentation and their ability to produce volatile compounds

Halophilic lactic acid bacteria were isolated from fish sauce mashes fermented at 1 to 12 months. Seven out of sixty-four isolates were selected according to their proteolytic activity and growth at 25% NaCl for characterization and investigation of volatile compound production. All selected isolates were Gram-positive cocci with pairs/tetrads and grew at 0-25% NaCl, pH 4.5-9.0. Results of 16S rRNA gene sequence analysis showed 99% homology to Tetragenococcus halophilus ATCC 33315. The restriction fragment length polymorphism (RFLP) patterns of all isolates were also similar to those of T. halophilus ATCC 33315. These isolates were, thus, identified as T. halophilus. All isolates hydrolyzed fish protein in the medium containing 25% NaCl. Intracellular aminopeptidase of 7 isolates exhibited the highest activity of 2.85-3.67 U/ml toward Ala-p-nitroanilide (Ala-pNA). T.halophilus strains MS33 and M11 showed the highest alanyl aminopeptidase activity (P < 0.05), and produced histamine in mGYP broth containing 5 and 25% NaCl in the level of 6.62-22.55 and 13.14-20.39 mg/100 ml, respectively. Predominant volatile compounds of fish broth containing 25% NaCl inoculated with T. halophilus MS33 and MRC5-5-2 were 1-propanol, 2-methylpropanal, and benzaldehyde, corresponding to major volatile compounds in fish sauce. T.halophilus appeared to play an important role in volatile compound formation during fish sauce fermentation.     

The relationship between sensory quality and volatile compounds in raw juice processed from elderberries (Sambucus nigra L.)

Elderberry juice was processed by pressing of 101 samples of elderberries (Sambucus nigra L.) picked in Austria, England and Denmark at optimum maturity. Taste panels trained in determination of elderberry flavour evaluated the juices and the results from the sensory evaluation were correlated to the content of volatile compounds. The volatile compounds were isolated from elderberry juices by dynamic headspace technique and analysed by GC-FID and GC-MS. A total of 59 volatile compounds were identified, 9 of which have not previously been detected in elderberry products. A total of 53 compounds occurred in quantifiable amounts and significant differences among the investigated elderberry samples were observed for 50 compounds. The importance of the isolated volatile compounds to elderberry flavour was determined by classical factor analysis using the results from the sensory evaluation and information on the odour of the individual volatile compounds. Classical factor analysis were used including determination of eigenvalues, factor loadings and factor scores by varimax rotation of standardised variables for extraction of four non correlated factors (principal components) explaining approximately 73% of the variation in elderberry flavour. Twenty-eight volatile compounds and sensory quality were included in the four factors. Using the compounds with highest numerical values (loadings) the four factors were named: fresh-elderberry-elder flower (35.2%), fresh-fruity-sweet (17.3%), fresh-fruity (13.7%) and green-floral-fruity (6.7%). Three compounds with characteristic elderberry odour (-damascenone, nonanal, dihydroedulan) were closely correlated with the sensory quality of elderberry together with compounds with fruity, floral, green and/or miscellaneous odours.     

进口鸡翼中单核细胞增生李斯特菌的鉴定及其 挥发性产物分析

目的对从进口鸡翼中分离的菌株F7-10进行种属鉴定,并通过顶空气相色谱-质谱联用法(headspace gas chromatography-mass spectrometry,HS-GC-MS)分析其液态培养代谢的挥发性产物。方法通过VITEK 2 Compact全自动微生物鉴定系统分析菌株的生理生化特征,结合16S r RNA基因和prf A基因PCR扩增测序鉴定分离菌株,通过HS-GC-MS分析分离菌株F7-10代谢的挥发性产物,并与单核细胞增生李斯特菌ATCC 13932、格氏李斯特菌ATCC 700545和英诺克李斯特菌ATCC 33090的代谢挥发性产物进行比较分析。结果菌株F7-10为革兰氏阳性菌,生理生化特征与单核细胞增生李斯特菌(Listeria monocytogenes)的相似性为98%,协同溶血实验在靠近金黄色葡萄球菌的接种端溶血增强;16S r RNA基因序列与单增李斯特菌标准菌株的相似性为99%,prf A基因特异性扩增出现预期大小的目的片段。菌株F7-10在营养肉汤中代谢的挥发性产物主要有乙醇、3-羟基-2-丁酮、乙酸、丁酸、3-甲基戊酸、十二醇等,与单增李斯特菌标准菌株的代谢挥发性产物种类相似,但含量有差别。结论进口鸡翼中分离的菌株F7-10鉴定为单核细胞增生李斯特菌,该菌产生的挥发性产物可为单核细胞增生李斯特菌的鉴定提供参考。     

Headspace analysis of volatile flavour compounds of teleme cheese made from sheep and goat milk

The headspace compounds of teleme cheese made from sheep's milk, goats' milk or mixture of sheep's and goats' milk (50:50) were analysed during ripening by static headspace gas chromatography–mass spectrometry. A total of 21 major compounds were identified, including aldehydes (7), alcohols (5), ketones (4), and acids (2). All types of cheeses contained approximately the same volatiles at different concentrations. The total volatile compounds (TVC) increased during ripening. Cheeses made from sheep's milk showed the highest level of TVC, whereas cheeses made from goats' milk showed the lowest one.     

固相微萃取-气相色谱质谱联用分析辣椒油树脂挥发性成分

以河北望都产朝天椒为原料,利用固相微萃取-气相色谱质谱联用技术分析风干辣椒和焙烤辣椒油树脂挥发性成分。从风干辣椒中共鉴定出28种挥发性成分,其中主要挥发性成分为:乙酸(14.43%),2,4a,5,6,7,8,9,9a-八氢-3,5,5-三甲基-9-亚甲基1H-苯(并)环庚烯(5.74%),1-甲氧基-4-(1-丙烯基)-苯(5.67%),10s,11s-Himachala-3(12),4-diene(41.14%)。从焙烤辣椒中共鉴定出32种挥发性成分,其中主要挥发性成分为:β-月桂烯(3.14%),2,6-二甲基-2,6-辛二烯(5.54%),2-异丙基-5-甲基-3-环己烯-1-酮(10.15%),1a,2,3,4,4a,5,6,7b-八氢-1,1,4,7-四甲基-环丙苷菊(3.51%),4-(1-甲乙基)-苯甲醛(6.54%),苯基乙酸酯(8.12%),1-甲氧基-4-(1-丙烯基)-苯(23.45%),1,6-二甲基-4-(1-甲乙基)-萘(3.69%)。风干辣椒和焙烤辣椒油树脂挥发性成分组成有着很大的差别。     

High pressure processing of Australian navel orange juices: Sensory analysis and volatile flavor profiling

Navel orange juices subjected to high pressure processing (HPP) and temperature treatment (TT) were stored at 4 and 10 °C for up to 12 weeks to establish the shelf-life of such products. The processed juices and a control juice, stored at − 20 °C, were assessed by a trained sensory panel and a consumer acceptance panel at 0, 1, 2, 4, 8 and 12 weeks or until such time that the juices were considered unfit for consumption. Untreated juice stored at 4 °C was similarly assessed for up to 2 weeks and untreated juice stored at 10 °C was assessed for up to 1 week. The volatile components of corresponding juices were isolated by SPME and the extracts were analyzed by GC–MS. Twenty key aroma compounds were selected for quantification and these data were used to monitor the change in volatile content of the juices during storage. The study showed that the odor and flavor of the HPP juice was acceptable to consumers after storage for 12 weeks at temperatures up to 10 °C. However, only the TT juice stored at 4 °C was acceptable after the same length of storage.

Industrial relevance

Orange juice is a sensitive product subject to a high microbial load that can tolerate only moderate heat treatment without the destruction of the product’s delicate aroma and flavor characteristics. High pressure processing at moderate pressures and storage at refrigeration temperatures have been evaluated as means of maximizing microbial inactivation while maintaining consumer acceptability of the product. The sensory and analytical data presented demonstrate that high pressure processing with refrigeration can extend the shelf-life of orange juice while maintaining consumer acceptability.     

Determination of volatile compounds of precooked prawn (Penaeus vannamei) and cultured gilthead sea bream (Sparus aurata) stored in ice as possible spoilage markers using solid phase microextraction and gas chromatography/mass spectrometry

BACKGROUND: Solid phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) have been reported as useful techniques for analysing volatile compounds to monitor fish freshness. In this study, SPME/GC/MS was applied to cultured gilthead sea bream and precooked prawn stored in ice for 6 days in order to find possible markers of spoilage. Total volatile basic nitrogen (TVB‐N) was also determined as a common index of spoilage. RESULTS: The TVB‐N value at the end of the storage period for cultured gilthead sea bream (302.40 ± 8.50 mg kg^?1) was within the range of acceptability for edible fish (300–400 mg kg^?1) but could be considered at the beginning of spoilage. For precooked prawn the TVB‐N value at day 6 (863.04 ± 7.84 mg kg^?1) was not acceptable for human consumption. SPME/GC/MS identified 30 compounds in cultured gilthead sea bream and 49 compounds in precooked prawn. In particular, 3‐methyl‐1‐butanol, 2‐methylbutanal, 3‐methylbutanal and 3‐hydroxy‐2‐butanone increased during refrigerated storage both in the two species investigated here and in other species reported elsewhere and could be considered as markers of spoilage. CONCLUSION: This study confirmed that SPME/GC/MS can be considered an efficient method suitable for analysing the volatile compounds of both raw fish and fishery products in order to monitor loss of freshness. Copyright © 2008 Society of Chemical Industry