SDE and SPME Analysis of Flavor Compounds in Jin Xuan Oolong Tea

Simultaneous distillation‐extraction (SDE) and solid phase micro extraction (SPME) are procedures used for the isolation of flavor compounds in foods. The purpose of this study was to optimize SDE conditions (solvent and time) and to compare SDE with SPME for the isolation of flavor compounds in Jin Xuan oolong tea using GC‐MS and GC‐O. The concentration of volatile compounds isolated with diethyl ether was higher (P < 0.05) than for dichloromethane and concentration was higher at 40 min (P < 0.05) than 20 or 60 min extractions. For SDE, 128 volatiles were identified using GC‐MS and 45 aroma active compounds using GC‐O. Trans‐nerolidol was the most abundant compound in oolong tea. The number of volatiles identified using GC‐MS was lower in SPME than SDE. For SPME, 59 volatiles and 41 aroma active compounds were identified. The composition of the volatiles isolated by the 2 methods differed considerably but provided complementary information.     

A study of volatile flavour substances in Dalmatian traditional smoked ham: Impact of dry-curing and frying

Volatiles from Dalmatian prosciutto were isolated by solvent extraction (SE), simultaneous distillation extraction (SDE) and nitrogen purge and steam distillation (NPSD) and analyzed by GC and GC–MS. In all, 46 compounds were identified by SDE and SE (including fatty acids, aldehydes, phenols, esters, ketones and others), while 81 compounds were identified by NPSD (headspace volatiles including phenols, aldehydes, hydrocarbons, ketones, alcohols, esters and heterocyclic compounds). Regarding the impact of dry curing period on the volatiles, an increase in the percentages of aldehydes and esters during the ripening of the prosciutto was observed. Quantitative percentage differences among fried and raw samples were particularly evident in respect of aldehydes (SDE and SE). The NPSD method provided additional information of the volatiles from fried ham, since the pyrazines and most of the lower aldehydes that are important thermally derived flavour compounds were only isolated by NPSD (not by SE and SDE).     

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     

Study of the volatile profile characteristics of longan during storage by a combination sampling method coupled with GC/MS

BACKGROUND: Longan (Dimocarpus longan Lour.) is a kind of subtropical fruit, but it has a very short shelf life under normal ambient conditions. In this work, a combination sampling method, including headspace solid phase micro‐extraction (HSSPME), simultaneous distillation extraction (SDE) and steam distillation (SD), was used to study the volatile profile characteristics of longan at the fresh and deteriorated storage phases followed by gas chromatography–mass spectrometry (GC‐MS) detection. The study would provide a method for investigating the volatile profile characteristics of longan during storage and some helpful clues for quality discrimination. RESULTS: In total, 28 and 22 volatile compounds of fresh and deteriorated longan were identified. Alkenes and esters were the main volatile components of longan. β‐ocimene accumulated, whereas allo‐ocimene and 3,4‐dimethyl‐2,4,6‐octatriene decreased during storage. Different volatile profile characteristics at the fresh and deteriorated storage phases obtained by HSSPME were specified by principal component analysis (PCA). Typical volatile compounds were distilled by a common model strategy. CONCLUSION: The volatile profiles of longan during storage were studied using a combination of sampling methods followed by GC‐MS detection. Five typical volatiles contributing significantly to the difference in volatile profile characteristics of longan at the fresh and deteriorated storage phases were distilled using a common model strategy. These compounds are potential bio‐markers for longan degradation. Tentative results suggest that combining HSSPME with conventional volatile isolation methods would provided more representative data on changes in the volatile compounds of longan during storage and some helpful clues for quality discrimination. Copyright © 2008 Society of Chemical Industry     

Comparison of isolation methods for the determination of buckwheat volatile compounds

Five different isolation techniques were combined with gas chromatographic–mass spectrometric determination of aroma compounds from buckwheat: dynamic headspace (DHS) with cryotrapping or sorbent trapping, solid-phase microextraction (SPME), headspace sorptive extraction (HSSE), solvent extraction (SE) and simultaneous distillation–extraction (SDE). Optimisation of each technique is presented, as well as comparison of the chemical profiles obtained by them. Solvent extraction with methanol resulted in the isolation of rather polar and less volatile compounds and was deemed least suitable for the odour-active compounds. Only SPME with DVB/CAR/PDMS fibre was suitable for the isolation of highly volatile compounds in a wider polarity range. DHS extracted the smallest number of compounds, but with the comparable chemical profile as obtained by SDE, which was chosen as the most suitable technique to obtain the aroma compounds of cooked buckwheat. The applied isolation techniques are complementary in their ability to extract a representative aroma profile of buckwheat.     

Physicochemical characteristics, textural properties and volatile compounds in comminuted sausages as affected by various fat levels and fat replacers

Physicochemical and textural properties, and volatile compounds of comminuted sausages with various added fat levels and fat replacers were evaluated. Sausages without added fat had higher expressible moisture and texture values, but their lightness and yellowness values were lower, as compared with sausages with 5%, 10%, or 15% fat. Increased fat levels with constant amounts of lean meat and added water increased the lightness and yellowness values, but tended the redness values tended to be similar. Low‐fat sausages (LFSs, <3%) containing non‐meat proteins, except egg white protein, had reduced texture values similar to those of regular‐fat counterparts (RFC). The addition of non‐meat proteins, except egg white protein, as components of fat replacers in LFS improved the textural characteristics, making them similar to those of RFC. LFSs containing sodium caseinate had reduced concentrations of pentadecanal and octadecanal, resulting in similar volatile compositions to those of RFC. Thus, sodium caseinate was the best non‐meat protein for the improvement of both texture and flavour of LFSs.     

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.     

Flavour profiles of low-fat comminuted sausages as affected by the addition of various sugars in combined with 0.1 m lysine

The study was performed to evaluate the flavour profiles of low-fat comminuted sausage (LFS) as affected by the addition of various concentrations of glucose, fructose and sucrose combined with 0.1  m lysine. Among thirty-five volatile compounds, the concentrations of furfural, 2-furan methanol, 2-methoxy phenol, 2-methoxy-4-methyl phenol, myristicine and pentadecanal occupied approximately 60% of the total concentration of volatile compounds identified in full- and low-fat smoked sausages. Phenols and hetero-compounds derived mainly from the smoking process were the predominant chemical groups. Nine volatile compounds were affected by fat content and the reduction of fat predominantly increased the headspace concentration of myristicin and pentadecanal. The headspace concentration of total volatile compounds detected in LFS control was significantly higher than those of LFS treatments with the various sugars and lysine. The headspace concentration of most volatile compounds decreased with the addition of various sugars. The results indicate that the addition of glucose, fructose and sucrose at the concentrations higher than 0.05  m in combination with 0.1  m lysine delays the release of some flavour compounds in LFS.     

Extraction of volatile organic compounds from leaves of Ambrosia artemisiifolia L. and Artemisia annua L. by headspace-solid phase micro extraction and simultaneous distillation extraction and analysis by gas chromatography/mass spectrometry

This study was designed to analyze the volatile organic compounds in the leaves of Ambrosia artemisiifolia L. and Artemisia annua L. from Korea. For extraction of volatile compounds, headspace-solid phase micro extraction (HS-SPME) and simultaneous distillation extraction (SDE) were applied and analyzed by gas chromatography/mass spectrometry (GC/MS). From the results, SDE extraction was found to give the highest concentration of volatile compounds with an average concentration of 1,237.79 mg/kg for A. annua L. leaves compared to 1,122.73 mg/kg by HS-SPME technique. A total of 116 volatile organic compounds were identified, including 76 similar volatile organic compounds detected by both the methods of extraction in leaves of subject species at varying concentrations. Among these 33 volatile organic compounds were reported for the first time from the subject plant species. Thus the present research findings extend the characterization of volatile organic compounds from leaves of A. annua L. and A. artemisiifolia L. species and reported some distinguishing compounds which may be used for their discrimination.     

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     

紫苏不同部位精油成分及体外抗氧化能力的比较研究

采用同时蒸馏萃取法提取紫苏不同部位(叶、花蕾、梗和籽)精油,利用气相色谱-质谱法对精油成分进行分析,并比较不同部位精油体外抗氧化能力。结果表明：紫苏叶精油得率相对最高,达到8.21‰。从紫苏叶、花蕾、梗和籽精油中依次鉴定出40、53、29和26种组分,分别占各自精油总量的99.85%、99.25%、96.73%和97.51%。不同部位精油成分和相对含量差异显著,共有组分仅5种,分别是2-己酰呋喃、4-(2-甲基环己烯)-2-丁烯醛、石竹烯、芳樟醇和石竹素,其中相对含量最高的组分均是2-己酰呋喃。紫苏不同部位精油均具有一定的抗氧化能力,紫苏叶精油清除DPPH自由基的能力较强,紫苏籽精油清除羟自由基的能力较强。     

同时蒸馏萃取技术分析酿酒原料青稞中挥发性化合物的研究

建立了同时蒸馏萃取-气相色谱/质谱联用技术（SDE-GC/MS）分析青稞中挥发性化合物的方法,获得 26 种组分的定性和定量结果。采用这一技术对瓦蓝、肚里黄、白青稞、黑老鸭等四种青稞酒原料进行分析,结果表明不同青稞品种间化合物种类接近又各具特点。本研究还对同时蒸馏萃取技术参数优化、青稞中主要挥发性组分进行了分析研究。     

Identification of volatile components in Chinese Sinkiang fermented camel milk using SAFE,SDE, and HS-SPME-GC/MS

The volatile components of Chinese Sinkiang fermented camel milk were isolated by solvent assisted flavour evaporation (SAFE), simultaneous distillation extraction (SDE, dichloromethane and diethyl ether as solvent, respectively) and headspace solid-phase microextraction (HS-SPME, CAR/PDMS, PDMS/DVB and DVB/CAR/PDMS fibre extraction, respectively) and analysed by GC/MS. A total of 133 volatile components were identified under 6 different conditions, including 30 esters, 20 acids, 18 saturated alcohols, 15 unsaturated aliphatic alcohols, 8 saturated ketones, 9 saturated aldehydes, 8 unsaturated aliphatic aldehydes, 6 furans, 5 sulphur-containing compounds, 5 ethers, 5 lactones, 3 other compounds, and 1 unsaturated aliphatic ketone. Three pretreatment methods were compared, assisted by principal component analysis (PCA). The results indicated that the volatile components obtained using different methods varied greatly both in categories and in content, and therefore, a multi-pretreatment method should be adopted together with GC/MS. A total of 71 aroma-active compounds were detected by gas chromatography-olfactometry (GC–O), among which 66 aroma-active compounds were found by SDE (60, dichloromethane as solvent; 24, diethyl ether as solvent), 26 by SAFE.     

不同方法提取辛夷挥发油化学成分与热失重分析的比较

辛夷是一种传统的中药材,且具有明显的香气特征,可以作为香料使用。本文采用水蒸气蒸馏萃取、同时蒸馏萃取、超临界二氧化碳(CO2)萃取和超声波辅助萃取法对辛夷挥发油进行了提取,采用气相色谱-质谱联用(GC/MS)技术对辛夷挥发油成分进行了鉴定和检测,并对挥发油进行了热失重研究。结果显示,4种不同提取方法的挥发性成分共有61种,主要是萜烯类、醇类、醛酮类和酯类等;通过对4种不同提取方法挥发油的热失重分析发现,水蒸气蒸馏萃取、同时蒸馏萃取和超声波辅助萃取法提取的挥发油的热失重曲线类似,均呈现四个失重阶段,但略有差异;超临界CO2萃取法提取的挥发油热失重曲线为三个失重阶段。4种失重曲线的不同说明4种提取方法提取的挥发性成分存在差异。     

兔肉挥发性风味成分提取效果的比较

为比较不同提取技术对兔肉挥发性风味物质的提取效果,明确兔肉特征风味物质。采用同时蒸馏萃取（simultaneous distillation extraction,SDE）、固相微萃取（solid phase micro extraction,SPME）和超临界二氧化碳流体萃取（supercritical carbon dioxide fluid extraction,SFE）3 种常用方式,提取兔肉风味物质,定量加入2,4,6-三甲基吡啶,通过气相色谱-质谱法进行定性和定量研究,比较提取率差异,确定兔肉主体风味成分。结果显示：SDE法提取到包括烃、醇、醛、酸、酯、酮、醚和杂环共8 类75 种化合物;SPME法提取到烃、醛、酮和酯共4 类41 种化合物;SFE法提取到烃、醇、醛、酯和杂环共5 类38 种化合物。提取物质种类：SDE＞SFE＞SPME,提取物质量：SFE＞SDE＞SPME,提取量：SPME＞SFE＞SDE。通过气味活度值法,确定己酸、己醛、辛醛、壬醛、2,4-癸二烯醛和1-辛烯-3醇为兔肉主体风味物质。     

Effect of fat content on aroma generation during processing of dry fermented sausages

Dry fermented sausages with different fat contents were produced (10%, 20% and 30%). The effect of fat content and ripening time on sensory characteristics, lipolysis, lipid oxidation and volatile compounds generation was studied. Also, the key aroma components were identified using gas chromatography (GC) and olfactometry. High fat sausages showed the highest lipolysis and lipid oxidation, determined by free fatty acid content and thiobarbituric acid reactive substances (TBARS), respectively. A total of 95 volatile compounds were identified using SPME, GC and mass spectrometry (MS). Fat reduction decreased the generation of lipid derived volatile compounds during processing while those generated from bacterial metabolism increased, although only at the first stages of processing. The consumers preference in aroma and overall quality of high and medium fat sausages was related to the aroma compounds hexanal, 2-nonenal, 2,4-nonadienal, ethyl butanoate and 1-octen-3-ol which contributed green, medicinal, tallowy, fruity and mushroom notes.     

Amorphous cellulose gel as a fat substitute in fermented sausages

Fermented sausages were produced with 25%, 50%, 75% or 100% of their pork back fat content replaced by amorphous cellulose gel. The sausage production was monitored with physical, chemical and microbiological analyses. The final products were submitted to a consumer study, and the volatile compounds of the final products were extracted by solid-phase microextraction and analyzed by GC/MS. The reformulated fermented sausages had significant reductions in fat and cholesterol, and the volatile compounds derived from lipid oxidation were also reduced in the final products. These results suggest that the substitution of up to 50% of the pork back fat content by amorphous cellulose gel can be accomplished without a loss of product quality, enabling the production of fermented sausages with the levels of fat and cholesterol decreased by approximately 45% and 15%, respectively.     

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.     

烟用香精香气成分提取方法的选择

采用同时蒸馏萃取、水蒸气蒸馏、固相微萃取和溶剂萃取法分别提取烟用香精中的挥发性成分,并采用GC和GC/MS进行测定,通过比较色谱指纹图谱中提取特征组分的数目、含量和表征香精指纹性的能力,以及提取方法的重复性,得到其最佳提取方法。结果表明:同时蒸馏萃取法能最大程度提取AB1香精样品的风味成分并具有较好的重复性,可以满足建立指纹图谱的要求。