Analysis and characterization of aroma‐active compounds of Schizandra chinensis (omija) leaves

Volatile components from leaves of Schizandra chinensis (omija), a native plant of Korea, were extracted by simultaneous distillation–extraction (SDE) and analyzed by gas chromatography–mass spectrometry (GC‐MS) using two types of capillary column with different polarities (DB‐5MS and DB‐Wax). The GC‐MS analysis of volatile compounds obtained by SDE revealed that germacrene D is the most abundant compound (22.6%) in omija leaves, followed by β‐elemene (17.4%), (E)‐2‐hexenal (8.7%), and (E)‐β‐ocimene (7.2%). Aroma‐active compounds were determined by gas chromatography–olfactometry (GC‐O) using the aroma‐extract‐dilution analysis method. (E,Z)‐2,6‐Nonadienal (cucumber) was the most intense aroma‐active compound due to its higher flavor‐dilution factor (243–729) than any other compound. (Z)‐3‐Hexenal (green/apple), (E)‐2‐hexenal (green/fruity), and (E)‐β‐ocimene (wither green/grass) were also identified as important aroma‐active compounds by GC‐O. In addition, the volatile compounds were extracted by solid‐phase microextraction (SPME), and the quantitative analysis of the SPME samples gave slightly different results, depending on the type of SPME fiber, compared with those from SDE, However, the aroma‐active compounds identified in SPME were similar to those in SDE. Copyright © 2004 Society of Chemical Industry     

Rapid Analysis of Flavor Volatiles in Apple Wine Using Headspace Solid‐Phase Microextraction

Flavor volatiles are important components of alcoholic beverages. In this study, headspace solid‐phase microextraction and gas chromatography—mass spectrometry (HS‐SPME‐GC‐MS) were investigated for the determination of flavor‐contributing volatiles for apple wine. HS‐SPME parameters were defined, including fiber coatings, extraction time, and extraction temperature. Good linearity, recoveries, and repeatability of the SPME method using carboxen‐polydimethylsiloxane (carboxen‐PDMS) fiber were obtained with r² values, recoveries, and relative standard deviations ranging from 0.9112 to 0.9960, 80.23% to 110.21%, and 1.5% to 6.4% respectively using standard solution. No significant effects of ethanol concentration on headspace concentrations of analytes were observed when ethanol concentration changed from 0% to 12% (v/v), indicating that the HS‐SPME‐GC‐MS method can be used for the determination of flavor volatiles in apple wine with an alcohol content below 12% (v/v) as well as in apple juice, and the method enables the monitoring of volatiles in mash during fermentation.     

固相微萃取与同时蒸馏萃取法分析香精成分比较

分别采用同时蒸馏萃取法与固相微萃取法对烟草香精中的香味成分进行萃取 ,再用气相色谱 /质谱联用法和气相色谱法进行了定性和定量 ,并对这 2种萃取方法鉴定出的化学成分、重复性和定量值进行了比较。结果显示 :同时蒸馏萃取法具有良好的重复性和较高的萃取量 ,适合于烟用香精香味成分的定量分析 ;固相微萃取法具有快速简便、不使用溶剂和样品检测非破坏性等优点 ,适合于香精的剖析定性。     

Characterization of Aroma Compounds in Chinese Bayberry (Myrica rubra Sieb. et Zucc.) by Gas Chromatography Mass Spectrometry (GC‐MS) and Olfactometry (GC‐O)

Abstract: The aroma‐active compounds in Chinese bayberry were identified using gas chromatography‐olfactometry (GC‐O) and GC‐mass spectrometry techniques. The volatile compounds were extracted using Liquid–liquid extraction, solvent‐assisted flavor evaporation and headspace solid‐phase microextraction (HS‐SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4‐terpineol, linalool oxide, linalool, benzyl alcohol, α‐methylbenzyl alcohol, β‐phenylethanol, 3‐methylbutanoic acid and acetic acid, and so on. Moreover, HS‐SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, β‐caryophyllene) was predominant and its concentration represented over 89.9% of the overall compounds, and alcohols, aldehydes, ketones, esters, acids, and others were typically present in lesser amounts. Finally, principal component analysis revealed that there was also significant difference between immature and mature waxberry fruits     

Comparison of simultaneous distillation extraction (SDE) and solid‐phase microextraction (SPME) for the analysis of volatile compounds in dry‐cured ham

Simultaneous distillation extraction (SDE) and solid‐phase microextraction (SPME) using a carboxen/polydimethylsiloxane fibre were compared for their effectiveness in the extraction of volatile compounds from dry‐cured ham samples. A higher number of compounds was detected using SPME owing to the use of a solvent delay time in the GC‐MS analysis of SDE extracts. SPME was more efficient in extracting low molecular weight and high volatility compounds, while SDE was able to extract compounds with low volatilities that were not extracted using SPME. Both techniques satisfactorily extracted most volatiles previously highlighted as odour‐active compounds in dry‐cured ham. However, the ratio between some compounds from lipid oxidation and those from degradation of amino acids was much lower in SDE extracts than with SPME, which could be a consequence of the development of Strecker degradation of amino acids during distillation in SDE owing to the high temperatures used. Similarly, diunsaturated aldehydes detected in SDE extracts were absent using SPME, probably owing to oxidation of polyunsaturated fatty acids in SDE as a consequence of the temperature during extraction. Copyright © 2004 Society of Chemical Industry     

The comparison of physico-chemical and textural properties, as well as volatile compounds, from low-fat and regular-fat sausages

In order to determine the optimum method for extraction of the entire flavour profile of sausages, three extraction techniques, solvent extraction (SE), purge and trap (PT), and simultaneous distillation extraction (SDE), were compared. Similarly, to effectively analyse the volatile compounds of low‐fat (<3%) and regular‐fat (approximately 15%) sausages, three isolation techniques were investigated and gas chromatography (GC) and gas chromatography–mass spectrometry (GC/MS) were used for final identification of compounds. A total of thirty‐three volatile compounds were identified in the sausages by SDE, twelve by SE, and nine by PT. In the SE method, fats interfered in the extraction of some volatile components, resulting in lower recovery and longer isolation time when compared with the other two methods. The PT method might not be a good extraction method because of the loss of heterocyclic compounds. However, the SDE method showed greater yields and recognized more volatiles when compared with SE. Furfural, trans‐caryophyllene, and myristicine were the predominant volatile compounds extracted by SDE. These results suggest that the SDE method is the most efficient method in isolating volatile compounds in both regular‐ and low‐fat sausages. The amounts of volatile compounds, such as, 4‐acethyl‐3‐methyl pyrazole, 1,4‐dimethyl benzene, p‐ethylguaiacol and β‐caryophyllene were higher in regular‐fat sausages; however, the amounts of myristicine and hexadecanoic acid were higher in low‐fat sausages.     

Volatile Composition and Aroma Activity of Guava Puree Before and After Thermal and Dense Phase Carbon Dioxide Treatments

Volatiles from initially frozen, dense phase carbon dioxide (DPCD)‐ and thermally treated guava purees were isolated by solid phase microextraction (SPME), chromatographically separated and identified using a combination of gas chromatography‐mass spectrometry (GC‐MS), GC‐olfactometry (GC‐O), and GC‐pulsed flame photometric detector (GC‐PFPD, sulfur mode). Fifty‐eight volatiles were identified using GC‐MS consisting of: 6 aldehydes, 2 acids, 15 alcohols, 6 ketones, 21 esters, and 8 terpenes. Eleven volatiles were newly identified in guava puree. Hexanal was the most abundant volatile in all 3 types of guava puree. Ten sulfur compounds were identified using GC‐PFPD of which 3 possessed aroma activity and 3 were not previously reported in guava puree. Both treatments profoundly reduced total sulfur peak areas and produced different peak patterns compared to control. Thermal treatment reduced total sulfur peak area 47.9% compared to a loss of 34.7% with DPCD treatment. Twenty‐six volatiles possessed aroma activity. (Z)‐3‐Hexenyl hexanoate was the major contributor to the aroma of the freshly thawed and DPCD‐treated guava puree. DPCD treatment reduced total MS ion chromatogram (MS TIC) peak area 35% but produced a GC‐O aroma profile very similar to control. Whereas thermal treatment reduced total TIC peak area only 8.7% compared to control but produced a 35% loss in total GC‐O peak intensities.     

Determination of the Principal Volatile Compounds of Turkish Raki

Turkish Raki is a type of traditional aniseed spirit produced in different areas of Turkey. The amounts and the repartition of the alcoholic fermentation products (fusel alcohols, esters, and aldehydes) are mainly responsible for the flavours and quality of the spirit. Previous studies have been carried out on the quantification of the volatiles of the different aniseed spirits using GC and GC‐MS. In this study of 20 different commercial brands of bottled Raki and 5 homemade Turkish Raki products, the major volatiles and methanol were determined using direct injection with GC‐MS. SPME extraction was also used as a confirmation method for the separation of Raki volatiles. Eight different substances were successfully identified using SPME extraction. The results indicated that some homemade Turkish Raki products from the different regions contained slightly higher concentrations of the most studied compounds. The toxic compound methanol was detected only at a level far below the acceptable legal limit.     

Chemical analysis of French beans (Phaseolus vulgaris L.) by headspace solid phase microextraction (HS-SPME) and simultaneous distillation/extraction (SDE)

Headspace Solid Phase Microextraction (HS-SPME) involving divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fibre and simultaneous distillation/extraction (SDE) techniques were applied to study the volatile and semi volatile compounds of thawed and cooked Phaseolus vulgaris L. A total of 104 compounds were detected by GC and GC/MS. Thereof, 76 compounds were identified for the first time in this species. The major differences between HS-SPME and SDE were found in the content of identified alcohols (23.62% SDE versus 62.20% SPME), terpenoids (39.15% SDE versus 2.45% SPME), heterocyclic compounds (13.78% SDE versus 1.21% SPME), hydrocarbons (2.22% SDE versus 13.87% SPME) and esters (0.98% SDE versus 12.98% SPME). The SPME technique was found to be useful for rapid and routine quality controls of thawed French beans, while SDE is favourable to study the entire set of flavour volatiles in the corresponding cooked samples.     

Characterization of volatile compounds of pu-erh tea using solid-phase microextraction and simultaneous distillation–extraction coupled with gas chromatography–mass spectrometry

Two extraction methods, namely, solid-phase microextraction (SPME) and simultaneous distillation–extraction (SDE) both followed by gas chromatography–mass spectrometry were applied for the determination of a wide range of volatile compounds in pu-erh tea. The conditions of solid-phase microextraction including fiber selections and sampling condition optimization have been previously investigated. By the two methods, 79 volatile compounds belonging to different categories were identified. Among them, 61 volatile compounds were extracted by SDE and 67 by SPME. Qualitative and quantitative differences of pu-erh tea volatile profiles were observed by applying the two aforementioned extraction methods. SDE technique achieved higher percentages of high molecular weight alcohols, acids, and esters of low volatility, whereas SPME technique was found useful for analyzing low molecular weight alcohols, methoxy-phenolic compounds, aldehydes, ketones, and hydrocarbons of high volatility that were closely related to the characteristics of pu-erh tea aroma and its sensory perception. Therefore, SPME technique was a reliable extraction method for controlling pu-erh tea quality flavor.     

Hot and cold water infusion aroma profiles of Hibiscus sabdariffa: fresh compared with dried

Abstract: Calyxes from the Roselle plant (Hibiscus sabdariffa L.) were used to prepare cold (22 °C for 4 h) and hot (98 °C for 16 min) infusions/teas from both fresh and dried forms. Aroma volatiles were extracted using static headspace SPME and analyzed using GC‐MS and GC‐O with 2 different columns (DB‐5 and DB‐Wax). Totals of 28, 25, 17, and 16 volatiles were identified using GC‐MS in the dried hot extract (DHE), dried cold extract (DCE), fresh hot extract (FHE), and fresh cold extract (FCE) samples, respectively. In terms of total GC‐MS peak areas DHE ? DCE > FHE ? FCE. Nonanal, decanal, octanal, and 1‐octen‐3‐ol were among the major volatiles in all 4 beverage types. Thirteen volatiles were common to all 4 teas. Furfural and 5‐methyl furfural were detected only in dried hibiscus beverages whereas linalool and 2‐ethyl‐1‐hexanol were detected only in beverages from fresh hibiscus. In terms of aroma active volatiles, 17, 16, 13, and 10 aroma active volatiles were detected for DHE, DCE, FHE, and FCE samples, respectively. The most intense aroma volatiles were 1‐octen‐3‐one and nonanal with a group of 4 aldehydes and 3 ketones common to all samples. Dried samples contained dramatically higher levels of lipid oxidation products such as hexanal, nonanal, and decanal. In fresh hibiscus extracts, linalool (floral, citrus) and octanal (lemon, citrus) were among the highest intensity aroma compounds but linalool was not detected in any of the dried hibiscus extracts. Practical Application: Hibiscus teas/infusions are one of the highest volume specialty botanical products in international commerce. The beverage is consumed for both sensory pleasure and health attributes and is prepared a number of ways throughout the world. Although color and taste attributes have been examined, little information is known about its aroma volatiles and no other study has compared extractions from both fresh and dried as well as extraction temperature differences. This is also, apparently, the first study to identify the aroma active volatiles in hibiscus beverages using GC‐olfactometry. Manufacturers and consumers will now have a better understanding of why hibiscus teas prepared in different ways from either fresh or dried forms have a different flavor quality and intensity.     

Comparison of the characterisation of the fruit‐like aroma of Teucrium flavum L. subsp flavum by hydrodistillation and solid‐phase micro‐extraction

BACKGROUND: Teucrium species (Lamiaceae) are interesting for the food industry since many of them are used in the preparation of flavoured wines and beers, herbal teas, bitters and liqueurs. On this basis, the analysis of the aroma components of Teucrium flavum L. subsp. flavum growing in central Italy was carried out by means of both hydrodistillation (HD) and headspace solid‐phase micro‐extraction (HS‐SPME), coupled with GC/FID and GC/MS. RESULTS: A total of 102 components were identified in the essential oils, representing 99.0‐99.3% of the total oils. Sesquiterpenes hydrocarbons constituted the major fraction (48.5–49.4%), with the apple‐like flavour (Z,E)‐α‐farnesene being the major component. HS‐SPME allowed the analysis of the volatiles not only emitted by specific plant parts, but also by different parts within a single flower: flower calyx afforded the highest contribution, in terms of volatiles, to the aroma of the plant. CONCLUSION: The chemical profile of the volatile fraction obtained by HD and HS‐SPME, demonstrated the plant fruit‐like aroma, confirming the usefulness for flavouring wines, bitters and other kind of beverages, and also suggested other applications, as aroma and taste enhancer in food processing. In particular, SPME resulted in a very useful technique, which permits a choice between the part of the plant which has the highest concentration of a specific fragrance, and therefore establishes the best way of sampling during industrial applications of aromatic plants. Copyright © 2009 Society of Chemical Industry     

牛肉风味料的香气成分

采用Tenax-Gc（Diphenyl-PhenyleneOxide）吸附剂吸附－解吸法和同时蒸馏萃取法(SDE)两种方法提取牛肉风味料中的挥发性香气成分,并利用GC-MS（色质联用）进行了成分的分离与鉴定.结果表明,鉴定得出的化合物共104种,杂环化合物和含硫、氮化合物构成了牛肉风味的主体.比较两种提取方法得知吸附－解吸法有利于提取易挥发性化合物,而SDE法对提取中、高沸点化合物更有效.     

Analysis of Volatile Flavor Components in Steamed Rangia Clam by Dynamic Headspace Sampling and Simultaneous Distillation and Extraction

The volatile flavor components of steamed rangia clam (Rangia cuneata) were extracted by dynamic headspace sampling (DHS) and simultaneous distillation/extraction (SDE) techniques, and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC-coupled aroma perception. Twenty-two heterocyclic aroma compounds were identified. Volatile flavor compounds in other chemical classes, such as aldehydes, alcohols, ketones, and terpenes, also were identified. The unique clam aromas were contributed by a combination of S-, and N- containing compounds and ketones. In general, sampling methods (DHS and SDE) complemented each other in compounds detected in the sample. However, SDE gave more information on characteristic steamed clam flavors.     

固相微萃取法分析凤凰单枞乌龙茶香气组分

本文以凤凰单枞乌龙茶（Camellia sinensis）为材料，采用固相微萃取（solid Phase Microextraction，SPME）对其呈香组分进行研究。结果表明采用SPME萃取凤凰单枞乌龙茶香气组分，从桂花香型乌龙茶干茶样中检测出41种香气组分，而SDE法则检测到55种香气组分，两种方法都检测出高比例的芳樟醇、橙花叔醇、茉莉酸甲酯和吲哚。SPME法萃取了乌龙茶自身散发出的香气组分，避免了茶叶中易挥发或热不稳定的香气组分被破坏，减少了香气组分的测定误差和不稳定性。     

Free and Bound Volatile Chemicals in Mulberry (Morus atropurpurea Roxb.)

Mulberry (Morus atropurpurea Roxb.) is a popular and desirable fruit that is widely cultivated in China. Despite its popularity, the free volatile chemicals and glycosidically bound volatiles (GBVs) of mulberry have been minimally studied. To this end, we have investigated these compounds in 4 mulberry cultivars via solid phase extraction (SPE) and headspace solid phase microextraction with gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS). A total of 55 free volatile chemicals and 57 GBVs were identified and quantified. In 3 of the cultivars (“YFS,” “T10,” and “D10”), the GBVs were found in higher amounts than their free counterparts, corresponding to a ratio of 1.2 to 1.8. The characteristic aromas were determined by their odor activity values (OAVs) and by generating an aroma series (AS). A total of 20 volatile compounds had OAVs ≥ 1.0. In particular, ethyl butanoate, hexanal, (Z)‐3‐hexenal (E)‐2‐hexenal, (E)‐2‐nonenal, and eugenol had relatively high OAVs and were considered to be the key aromas contributing to the mulberry flavor. Consequently, mulberry was characterized by a variety of herbaceous scents having a background of sweet, spicy, fruity, and floral notes. The free volatiles exhibited strong herbaceous notes, whereas the GBVs were responsible for the sweet and spicy qualities of the fruit. Based on our results, 2 cultivars (“YFS” and “D10”) are proposed to be good candidates suitable for the further development of mulberry‐based food products due to their complex and desirable aromas.     

同时蒸馏萃取-气质联用分析乌梅中的挥发性成分

采用同时蒸馏萃取法提取两种不同工艺制成的乌梅中的风味成分。所得到的挥发性成分用气相色谱/质谱(GC/MS)法分离并分析鉴定,共鉴定出了69种挥发性成分。其中酚类15种,酸类8种,醇类2种,醛类5种,酯类6种,烃类26种,其它杂环类7种。两种乌梅的挥发性风味成分的种类和含量虽有差异,但是风味的主体成分基本相同。酚类及其衍生物应是提供乌梅烟熏香的最重要的成分。     

不同方法提取的海南黑、白胡椒香气物质GC-MS比较分析

分别采用固相微萃取法(SPME)、水蒸气蒸馏法(DDE)和同时蒸馏萃取法(SDE)对海南黑、白胡椒的香气成分进行提取,然后经气相色谱-质谱联用法结合计算机检索对其香气成分进行分析和鉴定。研究结果表明,从海南黑、白胡椒中共鉴定出香气物质96种。其中,对白胡椒,采用SPME法的提取物中鉴定出了59种化合物,占整个峰面积的90.20%;采用DDE法的提取物中共鉴定出了52种化合物,占整个峰面积的90.25%;采用SDE法的提取物中共鉴定出了26种化合物,占整个峰面积的84.64%。对黑胡椒,采用SPME法的提取物中鉴定出了36种化合物,占整个峰面积的93.07%;采用DDE法的提取物中共鉴定出了37种化合物,占整个峰面积的81.98%;采用SDE法的提取物中共鉴定出了34种化合物,占整个峰面积的78.17%。海南黑、白胡椒的主体香气物质主要有α-蒎烯、3-蒈烯、α-水芹烯、β-月桂烯、D-柠檬烯、石竹烯等烯烃类物质。同时,三种提取方法中,采用SPME法可更加全面地鉴定出胡椒的香气物质,而采用SDE法则可更好地对胡椒的主体香气物质进行浓缩。将这三种方法相结合可以更加全面地检测出海南黑、白胡椒的香气物质。