Reducing the Influence of the Thermally Induced Reactions on the Determination of Aroma-Active Compounds in Soy Sauce Using SDE and GC-MS/O

A method based on simultaneous distillation extraction (SDE) coupled with gas chromatography–mass spectrometry/olfactometry (GC-MS/O) was developed for the analysis of volatile profiles in soy sauce. Its optimum operating conditions were as follows: 100 mL soy sauce plus 100 mL saturated brine; 2 h extraction using 50 mL dichloromethane. Eighty-eight volatile compounds were identified. Of these, 26 aroma-active compounds were detected by GC-O including 3-(methylthio)propanal, 2-methoxy-4-vinylphenol, 2-methoxyphenol, 2-methylbutanoic acid, 2,3-butanedione, phenylacetaldehyde, 2-ethyl-6-methylpyrazine, 3-methylbutanal, 2-methylbutanal, 3-methyl-1-butanol, and 2-methyl-1-butanol (which occurred at a high odor intensity in both high-salt liquid-state fermentation soy sauce (HLFSS) and low-salt solid-state fermentation soy sauce (LSFSS). SDE analysis of the odorless soy sauce indicated 12 volatiles (mainly Strecker aldehydes and α-dicarbonyl compounds). Thus, the proportions of these compounds (1.94–54.07 %) shown in previous GC-MS results could result from thermal degradation of non-volatile compounds in soy sauce. Especially, the contribution of 3-methylbutanal, 2-methylbutanal, phenylacetaldehyde, 3-(methylthio)propanal, and 2,3-butanedione to the aroma of soy sauce could be overestimated by conventional SDE-GC-O. With a full consideration of such limitations, this study will improve the application of SDE on aroma analysis of complex food matrix.     

不同淀粉质原料对高盐稀态酱油香气品质的影响

为了研究不同淀粉质原料(面粉、麸皮)对高盐稀态酱油香气品质的影响,本文利用定量描述分析(QDA)对面粉类酱油(FSS)、麸皮类酱油(WSS)的感官特征进行分析,通过顶空-固相微萃取(HS-SPME)和液液萃取(LLE)结合气相色谱-质谱联用(GC-MS)定量对比分析了两种酱油挥发性化合物组成。FSS中酸香、土豆香、麦芽香显著性高于WSS,焦糖香、烟熏香显著性低于WSS(p0.05)。GC-MS共分离鉴定出94种挥发性化合物,其中以酸类、酮类、醛类占主要比例,HS-SPME法能萃取出较多的醛类、含硫化合物,LLE法对呋喃(酮)类、酸类化合物萃取效果较好。通过对酱油中17种关键香气活性物质定量分析以及香气活性值(OAV)的计算,有9种化合物OAV值大于20。其中3-甲基丁醛OAV值最高,HDMF、愈创木酚均有较高的OAV值,且在WSS中高于FSS,与感官分析中的焦糖香、烟熏香结果一致;FSS中2-甲基丁醛、3-甲硫基丙醛的OAV值高于WSS,与麦芽香、土豆香感官分析结果相符。     

应用GC-O和GC-MS分析酱香型习酒中挥发性香气成分

利用液液萃取法(LLE)提取酱香型习酒中的香气化合物,按照酸碱性将萃取组分分离,获得酸性/水溶性、中性、碱性三个组分,通过气相色谱-闻香法(GC-O)结合气相色谱-质谱(GC-MS)分别进行香气成分分析。在具有典型酱香特征的习酒中共检测出72种香气化合物,其中酸性组分29种,中性组分43种,碱性组分22种,14种香气化合物在两种或两种以上组分中均可检测到。研究发现酱香型习酒中主要的香气物质是酯类、醇类、挥发性有机酸、呋喃类、芳香族类、酚类、醛酮类、吡嗪类以及含硫化合物等。香气强度较大的物质有丁酸乙酯、己酸乙酯、1-丙醇、3-甲基丁醇、乙酸、3-甲基丁酸、糠醛、四甲基吡嗪和二甲基三硫,这些物质对酱香型习酒的风味贡献较大。     

固相微萃取技术在豆瓣风味物质分析中的应用

应用顶空固相微萃取、气相色谱和质谱联用技术分析了豆瓣中的风味物质。对HS-SPME的条件如萃取头的选择、萃取时间、萃取温度进行了优化,建立了对豆瓣风味物质的萃取和分析条件———采用萃取头75μmCAR/PDMS在55℃下吸附30min。该方法具有很高的灵敏度,在样品前处理中简单、快速,适于分析豆瓣风味物质的组成。     

SDE和HS-SPME法与GC-MS/O联用分析阳江豆豉的香气活性化合物

采用同时蒸馏萃取法(SDE)和顶空-固相微萃取法(HS-SPME)结合气相色谱-质谱/嗅闻检测技术(GC-MS/O)深入研究阳江豆豉的香气成分,共鉴定出挥发性化合物174种。SDE法对高分子量、低挥发性物质,如呋喃酮、吡喃酮等,有良好的萃取效果;而HS-SPME法能萃取更多的高挥发性化合物,如小分子的酸和酯类。通过GC-O技术在两种方法的萃取物中共嗅闻到46个香气活性区域。其中9种共有化合物(2/3-甲基丁醛、2/3-甲基丁酸、3-甲硫基丙醛、苯乙醛、愈创木酚、3-羟基-2-甲基-4H-吡喃-4-酮和苯乙醇),以及香气强度较高(评分大于2.5分)的单方法检出化合物:SDE法4种(3-羟基-4,5-二甲基-2(5H)-呋喃酮、2-乙酰基-1-吡咯啉、2-丙烯基-3-甲基吡嗪和4-羟基-2,5-二甲基-3(2H)-呋喃酮)、SPME法1种(1-辛烯-3-醇),是阳江豆豉中的关键香气活性物质,对麦芽香、酸奶酪香、烤土豆香、花香、烟熏香、焦糖香和烤香等有贡献。     

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.     

应用GC-O和GC-MS研究蛇龙珠葡萄酒游离态挥发性香气成分

建立了提取和分离葡萄酒香气成分的方法。对烟台产区的蛇龙珠葡萄酒中的挥发性香气成分进行了定性分析,并比较其香气强度。葡萄酒样品的前处理包括:液液萃取、溶剂辅助萃取(SAFE)和香气成分分离技术,最终得到酸性/水溶性和中性/碱性两个组分。处理好的葡萄酒样品通过GC-O(gas chromatography-olfactometry)和GC-MS技术进行香气成分的定性和香气强度分析。从蛇龙珠葡萄酒中共鉴定出74种香气组分,包括酯类、醛酮类、醇类、酸类、萜烯类、酚类、甲氧基吡嗪类、降异戊二烯类和硫化物,其中3-甲基丁醇和β-大马酮是香气强度最强的组分。     

剁椒坯盐水酱油与普通酱油香气特征比较分析

采用固相微萃取-气质联用(SPME-GC-MS)方法,对剁椒坯盐水酱油和普通酱油的香气成分进行分析和鉴定。共鉴定出84种风味化合物,其中包括醇类物质12种,酯类物质12种,酸类物质15种,醛酮类物质15种,杂环类物质17种,酚类物质5种,烃类物质3种,醚类物质1种,含N化合物2种,含S化合物2种。其中剁椒坯盐水酱油比普通酱油的香气物质多15种,两种酱油的共有香气成分有30种,说明剁椒坯盐水酱油比普通酱油风味更优。     

HS-SPME-GC-MS分析新疆胡麻油挥发性成分的技术优化

采用顶空固相微萃取-气相色谱-质谱(headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术对新疆胡麻油挥发性成分测定分析进行优化,以期获得HS-SPME-GCMS分析胡麻油挥发性香气的最佳条件。结果表明,采用DVB/CAR/PDMS萃取头,在磁力搅拌条件下,胡麻油SPME最佳萃取条件为萃取温度50℃、萃取时间40 min、解吸时间4 min,在该条件下采用HS-SPME-GC-MS鉴定出的胡麻油挥发性物质达到46种,主要包括醛类、酮类、醇类、酸类、酯类、烷烃类、杂环类及其他类物质,其中醛类、杂环类和醇类总相对含量较高,分别为30.14%、12.73%和9.25%,分离鉴定效果较好。     

固相微萃取-气相色谱-质谱及气相色谱嗅闻技术分析双孢蘑菇汤的风味活性物质

测定双孢蘑菇汤的风味活性成分,分析这些风味活性成分对双孢蘑菇汤整体风味的重要贡献。利用顶空固相微萃取技术萃取双孢蘑菇汤的风味物质,通过气相色谱分别与质谱仪和嗅闻仪相联,对风味成分进行分离鉴定,比较不同萃取头的萃取效果及不同极性色谱柱的分离效果。结果表明：三相萃取头(DVB/CAR/PDMS)比两相萃取头(CAR/PDMS)得到的风味成分多7种;极性柱(DB-WAX)较弱极性柱(HP-5)得到的风味成分多3种,并且极性柱分离得到的蘑菇类风味成分比弱极性柱多,而弱极性柱分离得到了更多的吡嗪类化合物。蘑菇汤的主要风味活性物质包括C8类不饱和醇、酮(蘑菇味)、苯乙醛(花香)、2,5-二甲基吡嗪(爆米花味)、2,6-二甲基吡嗪(巧克力味)、正己醛(青草味)、3-甲基丁醛(果香)、2-乙酰噻唑(肉香)等。     

酒花浸膏关键性香气成分分析

采用固相微萃取（solid-phase microextraction,SPME）与溶剂辅助蒸发萃取（solvent-assisted evaporative extraction,SAFE）法结合气相色谱-质谱（gas chromatography-mass spectrometry,GC-MS）联用技术分析酒花浸膏中的香气成分,同时采用气相色谱-嗅闻仪（gas chromatography-olfactory,GC-O）结合香气提取稀释分析（aroma extraction dilution analysis,AEDA）方法和香气活性值（odor activity value,OAV）,最终确定酒花浸膏的关键性香气成分。结果显示,采用2 种萃取方法结合GC-MS在酒花浸膏中共鉴定出111 种香气成分;经GC-O分析共鉴定出27 种香气活性化合物,其中异丁酸乙酯、丁二酸二乙酯、2-甲基丁酸含量最高,结合风味稀释因子和OAV分析共同确认酒花浸膏的关键香气成分为异丁酸乙酯、2-甲基丁酸、异己酸乙酯、辛酸乙酯、癸酸乙酯等化合物。     

酱香型白酒液液微萃取-毛细管色谱骨架成分与香气重组

应用液液微萃取（LLME）、气相-质谱联用仪（GC-MS）研究酱香型白酒骨架成分。液液微萃取定量48种香气物质,确定29种骨架成分。通过52种物质香气重组,得到的模拟酒香气较为丰满,且富有层次感,呈现酱香型白酒的背景香,但未出现典型酱香。缺失实验表明酱香型白酒骨架成分中香气贡献较大的主要是酯类和醇类物质,其中：己酸乙酯、乙酸乙酯、丁酸乙酯、1-丙醇、2-苯乙醇以及3-甲基丁醇是重要的香气物质;缺失与添加实验验证了三甲基吡嗪、糠醛、4-乙基愈创木酚和呋喃扭尔（furaneol）与酱香型白酒的典型酱香无关。     

顶空固相微萃取- 气质联用法测定哈尔滨红肠的挥发性风味物质

为进一步探明烟熏灌肠类食品的风味特征,以哈尔滨红肠为对象,采用顶空固相微萃取制备样品,联合气质联用测定其主要挥发性物质。通过比较不同萃取头、萃取温度以及萃取时间对萃取效果的影响,获得较适的萃取条件：50/30μm DVB/CAR/PDMS萃取头、萃取温度50℃、萃取时间50min。采用气质联用对解吸物进行测定的结果表明,其挥发性风味物质的主要成分中醛类占17.59%、酮类占7.01%、酚类占7.27%、醇类占12.29%、烯萜类占9.39%、烷烃类占6.14%、含硫化合物占27.38%、杂环化合物占7.01%。     

基于SPME-GC-MS和PCA的不同萃取头对新疆烤羊肉香气成分萃取效果比较

以烤羊肉中关键挥发性物质的萃取效果为目的进行萃取头类别筛选。采用固相微萃取、气相色谱-质谱联用检测技术,对新疆石河子地区烤羊肉样品的挥发性风味物质的种类和组成进行提取和分析。以灵敏性及主成分分析（principal component analysis,PCA）法得到的载荷矩阵中投影大于0.80的关键共有物质作为筛选最优萃取头的依据,研究不同纤维涂层萃取头（75?μm?CAR/PDMS、65?μm?DVB/PDMS、85?μm?PA、100?μm?PDMS、50/30?μm?DVB/CAR/PDMS）与所萃取的挥发性物质之间的相关性。结果表明：经灵敏度检验、PCA后确认75?μm?CAR/PDMS为萃取烤羊肉样品中关键挥发性物质的最优萃取头,萃取得到样品中的关键香气成分为1-辛烯-3-醇、庚醛、正戊醛、十二醛、己醛、苯甲醛、1-十四炔、萘、4-甲基壬酸、反-2-癸烯醛、6-甲基庚醛、对异丙基苯甲醛、癸醛、壬醛、2-甲基-3-甲硫基呋喃、辛醛、联二苯。     

顶空固相微萃取法(SPME)在红葡萄酒香气成分测定中的应用研究

利用固相微萃取和气质固相微萃取联用技术对赤霞珠干红葡萄酒中的香气成分进行分析,研究了萃取时间、萃取温度、加电解质的量等对红葡萄酒中香气物质萃取的影响,优化了提取条件,建立了快速测定葡萄酒中香气物质的方法。质谱图中共分离出70个峰,利用计算机检索,结合已有的报道鉴定出65种香气物质,根据面积归一法测其相对含量,共占其色谱流出组分总量的98.46%。     

顶空固相微萃取-气相色谱-质谱法同时检测啤酒酿造大米中16 种风味物质含量

利用顶空固相微萃取-气相色谱-质谱技术,建立了一种同时检测啤酒酿造大米中16 种风味物质的定量分析方法。通过研究不同因素对风味物质萃取效果的影响,最终确定顶空固相微萃取最佳萃取条件为：使用50/30 μmDVB/CAR/PDMS萃取头、40 ℃条件下萃取60 min。质谱的采集使用选择离子监控模式。该方法的线性良好（R2＞0.99）,准确性高（16 种物质的加标回收率在85.7%～118.0%之间）,稳定性强（相对标准偏差均低于9.98%）,操作过程简便,能准确检测啤酒酿造大米中16 种风味物质的含量,对啤酒风味和质量控制具有一定作用。     

顶空-固相微萃取与气质联用法分析草菇中的香味成分

本文以享有“中国蘑菇”之称的草菇为原料，采用碳分子筛-聚二甲基硅氧烷（CAR／PDMS）涂层的固相微萃取头分别萃取新鲜草菇和干草菇蒸馏后的挥发性成分，并通过气质联用仪分析鉴定了其主要的香味成分。结果表明，固相微萃取有效地吸附了草菇中的挥发性成分，经NIST质谱数据库和文献对照，分别从干草菇和新鲜草菇中检测出48和29种成分，其中八碳化合物是最要的风味主体。     

Characterizing Red Radish Pigment Off-Odor and Aroma-Active Compounds by Sensory Evaluation,Gas Chromatography-Mass Spectrometry/Olfactometry and Partial Least Square Regression

Aroma-active compounds of red radish pigment extracts (water extract, phosphoric acidified water extracts (PAW), 10 min water or phosphoric acidified water preheated extracts (HW or HPAW), Chongqing, and Yunan extracts) were identified and characterized via sensory evaluation, gas chromatography-mass spectrometry (GC-MS), and gas chromatography-mass spectrometry with olfactometry (GC-MS/O). Three sensory attributes, namely radish odor (desirable) and radish off-odor and sulfur-like odor (undesirable), were selected to characterize the red radish pigment extracts. The correlation between the aroma-active compounds (GC-MS) and sensory attributes was studied using partial least square regression (PLSR). The sensory evaluation results revealed that Chongqing (9.30 and 8.80), water (9.00 and 9.10), Yunan (7.80 and 8.00), and HW (6.90 and 7.20) extracts showed higher radish off-odor and sulfur-like odor scores, while PAW-2.5 (7.70) and HPAW-2.5 (7.60) extracts showed higher radish odor scores. Sulfur-containing compounds, allyl isothiocyanate, 1-butyl isothiocyanate, acetonitrile, oxygen-containing compounds, terpenes, and naphthalene were positively and significantly correlated with radish off-odor and sulfur-like odor but negatively and significantly correlated to radish odor. 3-(Methylthio)propyl isothiocyanate and pyridine were positively and significantly correlated to radish odor. Additionally, 3-buten-1-yl isothiocyanate and 4-(methylthio)-3-butenyl isothiocyanate showed positive but not significant impact on radish odor. Based on their higher volatile concentration, the aroma-active compounds of the four extracts were evaluated using GC-MS/O. Thirty-three aroma-active compounds with different odor intensities were identified to be the major odorant compounds for red radish pigment extracts by panelists. Conclusively, the red radish pigment extraction conditions play a great role in its sensory characteristics.