顶空固相微萃取气质联用分析大蒜挥发性风味成分

采用顶空固相微萃取——气相色谱-质谱联用法分别测定生、熟大蒜的挥发性风味物质,检出生大蒜挥发性风味物质共17个化合物,主要成分有二烯丙基二硫醚(61.68%)、二-2-丙烯基四硫醚(13.61%)、甲基2-丙烯基二硫醚(12.46%)、二-2-丙烯基三硫醚(3.20%)、烯丙硫醇(2.10%)、二乙基-1,3-二噻烷(1.74%)、二烯丙基硫醚(1.30%)、甲基1-丙烯基二硫醚(1.10%)共8种物质,占总含量的97.19%。检出熟大蒜挥发性风味物质共30个化合物,主要成分有二烯丙基二硫醚(32.87%)、甲基2-丙烯基二硫醚(16.47%)、二烯丙基硫醚(10.88%)、二-2-丙烯基四硫醚(5.60%)、甲基烯丙基硫醚(4.19%)、甲基2-丙烯基三硫醚(3.45%)、二-2-丙烯基三硫醚(3.06%)、二甲硫醚(3.05%)、甲基环硫乙烷(2.22%)、二乙基-1,3-二噻烷(2.18%)、甲基1-丙烯基二硫醚(1.85%)、1,3,5-三噻烷(1.83%)、苯甲醛(1.35%)、二甲基二硫醚(1.31%)、二甲基三硫醚(1.17%)共15种物质,占总含量的91.79%。     

大葱挥发油含量与化学成分的分析

采用水蒸气蒸馏法提取莱芜鸡腿葱中的挥发油 ,测知其含量为 0 0 1 % ;并用毛细管气相色谱 /质谱法定性鉴别了挥发油中的 2 5种化学成分。其中含硫有机硫化合物为 2 0种 ;主要成分有 :丙基甲基硫代硫磺酸酯 ,甲基烯丙基硫代硫磺酸酯 ,甲基丙烯基三硫醚 ,烯丙基硫醇 ,甲丙基二硫醚 ,反式甲基烯丙基二硫醚 ,二甲基三硫醚 ,二丙基二硫醚 ,反式烯丙基丙基二硫醚 ,二甲基四硫醚 ,二丙基三硫醚 ,反式烯丙基丙基三硫醚 ,顺式烯丙基丙基三硫醚 ,甲硫醇 ,丙硫醇 ,二巯基甲烷 ,2 ,5 二甲基噻吩等含硫化合物 ,还鉴定出不饱和脂肪醛 1种 (3 ,7 二甲基 2 ,6 二辛烯醛 ) ,脂肪酮 1种 (十一酮 2 ) ,萜烯类化合物 2种 (2 甲基 庚稀 2和顺式 2 ,6 二甲基 2 ,6 辛二烯 ) ,挥发性无机化合物 1种 (SO2 )。     

顶空-固相微萃取-气质联用分析泡蒜中的挥发性成分

采用顶空-固相微萃取对泡蒜中挥发性成分进行了提取,并用气相色谱-质谱联用仪对提取出的挥发性成分进行了定性和定量分析。结果表明:从泡蒜中共鉴定出46个挥发性化合物,其中以含硫化合物为主体,共29种。泡蒜中的主要挥发性化合物有二烯丙基二硫醚(19.16%)、二烯丙基三硫醚(13.60%)、3-乙酰基-2-羟基-6-甲基-吡喃-4-酮(11.45%)、3-乙烯基-3,4-二氢-1,2-二噻烯(8.10%)、二烯丙基硫醚(4.07%)、2,4-二甲基噻唑(4.00%)、二烯丙基四硫醚(3.34%)、3-甲基-5-氨基-1,2,4-噻二唑(3.10%)。     

顶空固相微萃取结合气质联用分析沙葱中挥发性成分

沙葱是一种生长于荒漠地带的野生蔬菜,具有独特的气味。为了确定其挥发性成分,实验采用顶空固相微萃取技术(HS-SPME)对其挥发性成分进行萃取,然后用气相色谱质谱联用(GC-MS)进行检测。结果表明,共检测到24种化合物,在DVB/CAR/PDMS、PDMS/DVB、PA三种固相萃取头中,DVB/CAR/PDMS型号的萃取头萃取效果最佳;沙葱中主要挥发性成分是:2-己烯醛(27.74%)、甲基-2-烯丙基三硫醚(25.70%)、二甲基三硫化物(13.62%)、烯丙基甲基二硫醚(9.94%)、二烯丙基二硫(7.23%),占总成分的84.23%,其中2-己烯醛在沙葱中首次报道。     

芝麻香型白酒中含硫风味组分的分析

采用液-液萃取、固相微萃取的前处理方法提取扳倒井芝麻香型白酒中的香味物质成分,结合气相色谱(GC)、气相色谱-嗅闻仪联用(GC-O)及气相色谱-质谱联用(GC-MS)方法分析该香型白酒中含硫特征风味物质,结果表明,除了之前报道的4种含硫化合物外,还检测到二甲基二硫醚、二甲基四硫醚、3-甲硫基丙醛、糠硫醇、二异丙基二硫、二糠基二硫醚和甲基甲烷硫代磺酸酯。其中二甲基四硫醚、糠硫醇、二异丙基二硫、二糠基二硫醚和二甲基硫代亚磺酸酯是首次在芝麻香型白酒中发现。     

三种水果韭花酱香气成分分析

采用顶空固相微萃取(HS-SPME)与气相色谱-质谱联用(GC-MS)法分析对照韭花酱及加入3种不同水果(苹果、梨、菠萝)韭花酱的香气成分。在温度20℃、萃取时间30min 的条件下,对3 种水果韭花酱香气成分测定。结果：从苹果韭花酱、梨韭花酱、菠萝韭花酱中分别鉴定出7、7、11 种香气成分;4 种韭花酱的共有成分为甲硫醇、二甲基二硫醚、一硫二丙烯、二甲基三硫醚,其中苹果韭花酱中特有成分为1- 甲硫基-1- 丙烯-(E),菠萝韭花酱中特有成分为丁酸甲基酯、2-甲基-丁酸-甲基酯、甲基酯己酸、甲基丙基二硫醚、二噻烷。     

南极磷虾头胸部和腹部挥发性风味成分对比

采用顶空固相微萃取-气相色谱-质谱联用技术分析南极磷虾头胸部、腹部和整虾的挥发性风味成分,结合感觉阈值,利用相对气味活度法评价挥发性风味成分对总体风味的影响程度。结果表明,南极磷虾头胸部的主体风味成分为（E,Z）-2,6-壬二烯醛、3-甲基丁醛、3-甲硫基丙醛、壬醛、苯乙醛、D-柠檬烯、（Z）-4-庚烯醛、二甲基硫醚、辛醛、苯甲醛;南极磷虾腹部主体风味成分为二甲基三硫醚、癸醛、壬醛、3-甲基丁醛、辛醛、二甲基硫醚、D-柠檬烯、（Z）-4-庚烯醛;整虾的主体风味成分则包括二甲基三硫醚、癸醛、（E,Z）-2,6-壬二烯醛、3-甲基丁醛、壬醛、3-甲硫基丙醛、辛醛等物质。     

HS-GC-O-MS分析细叶韭花易挥发性风味成分

采用顶空-气相色谱-质谱联用技术对细叶韭花中易挥发性成分的萃取条件及气相色谱-质谱分离检测条件进行系统研究,并结合嗅闻仪确定挥发性风味成分。在选定HP-5MS色谱柱的分离条件下,最优顶空条件为样品用量1.0 g/20.0 mL顶空瓶,平衡温度100℃,平衡时间40 min。结果表明:经气相色谱-嗅闻-质谱联用分析,共分离得到52种化合物,确定结构46种,占总易挥发性成分的99.15%。其中,含硫类17种、醛类10种、烃类4种、酮类4种、呋喃类3种、醇类4种、酸类2种、芳香族类1种、萜类1种。根据嗅闻结果结合相对气味活度值可得,细叶韭花挥发性风味成分主要是二甲基硫醚、二甲基二硫醚、二甲基三硫醚、3-甲基丁醛、2-甲基丁醛、1,3-二噻烷。     

新鲜蒜黄香气活性成分分析鉴定

为分析鉴定新鲜蒜黄的香气活性成分,将新鲜蒜黄加水和二氯甲烷匀浆后进行溶剂辅助蒸发处理,获得风味萃取物。风味萃取物采用气-质联机分析检测出39个挥发性化合物,采用稀释法/气相色谱-嗅闻分析检测出35个气味活性区。根据质谱、保留指数、嗅闻的气味、相关文献,鉴定出35个香气活性化合物,其中3-乙烯基-1,2-二硫环己-4-烯、2-乙烯基噻吩、2,3-二甲基噻吩、二甲基三硫醚、二烯丙基二硫醚、1-氧-4,6-二氧杂环辛烷-5-硫酮、2-甲基二氢-3(2H)噻吩酮具有极高稀释因子(log₃FD ≥ 6),表明对新鲜蒜黄风味贡献大。本实验样品处理条件温和,最大化保持了新鲜蒜黄的风味,研究结果可为蒜黄的贮藏加工及开发利用提供指导。     

基于SAFE法分析市售小磨香油的关键风味成分

以市售小磨香油为研究对象,采用溶剂辅助风味蒸发萃取(SAFE)法萃取其挥发性风味成分,利用三重四级杆气相色谱-质谱联用进行半定量分析,结合相对气味活度值(ROAV)进行关键风味成分贡献度分析。结果表明：从市售小磨香油中共鉴定出107种挥发性风味成分,其中35种挥发性风味成分(ROAV≥0.01)具有典型的风味特征贡献,包括4种硫化物、5种酚类、10种吡嗪类、4种呋喃类、3种醛类、4种噻唑类、2种吡咯类、2种噻吩类和1种吲哚,使小磨香油呈现卷心菜味、鱼腥味、硫磺味、烟熏味、爆米花味、油香和烤芝麻味。14种ROAV≥0.10的风味成分(乙酰基吡嗪、2-呋喃甲醇、2,3-二甲基-吡嗪、2,3,5-三甲基吡嗪、二甲基二硫醚、二甲基三硫醚、甲基糠基二硫醚、硫醇酸甲酯、4-乙烯基-2-甲氧基苯酚、2-甲氧基苯酚、己醛、2-乙基-6-甲基吡嗪、2-甲基-3-呋喃硫醇和3-乙基-2,5-二甲基-吡嗪)被确认为小磨香油的关键风味成分。综上,采用该方法确定小磨香油的关键风味成分,不仅可扩充小磨香油的风味数据库,还可为芝麻油风味品质评价及品质调控提供重要的物质基础。     

Effects of pH Adjustment and Subsequent Heat Treatment on the Formation of Volatile Compounds of Garlic

Effects of pH adjustment during the blending of garlic cloves and subsequence heat treatment on the formation of volatile compounds of garlic were studied by means of gas chromatography (GC). The formation of the two isomeric cyclic compounds 3-vinyl-[4H]-l,2-dithiin and 2-vinyl-[4H]-l,3-dithiin, which were artifacts from allicin, was favored around pH 5.5. Formation of diallyl trisulfide, methyl allyl trisulfide, cis-1-propenyl allyl disulfide, isobutyl isothiocyanate, 2,4-dimethylfuran, 1,3-dithiane, aniline, methyl allyl sulfide, dimethyl disulfide and 3-methyl-2-cyclopentene-l-thione were favored in neutral or weak acidic conditions, whereas formation of diallyl disulfide, diallyl sulfide, methyl allyl disulfide, propenylthiol, propyl allyl disulfide and 1,2-epithiopropane were favored around pH 9.0.     

A New Essential Oil Chemotype of Allium Roseum Analyzed by an Apolar Column

This study deals with the chemical characterization of a medicinal and an aromatic plant of the Tunisian flora: Allium roseum var. odoratissimum, and aimed to identify new bioactive natural compounds in its flower essential oil. These compounds were extracted by hydrodistillation and were analyzed by GC and GC/MS, using an apolar column. The most important compounds characterized were organo-sulphurous (46%), including methyl 2-propenyl trisulfide, di-2-propenyl trisulfide, di-1-propenyl disulfide, di-2-propenyl disulfide, dimethyl trisulfide, methyl 2-propenyl disulfide, and di-1-propenyl trisulfide, found as 10.75, 9.07, 5.81, 4.98, 3.90, 3.30, and 2.53%, respectively. Moreover, heneicosane and pentacosane were identified for the first time at relatively high rates (8.18 and 4.49%, respectively) in the Allium roseum essential oil. This essential oil composition exhibited newly identified sulphurous compounds at relatively high rates (46.53%) when compared with what was found while using polar column.     

Characterisation of volatile sulphur-containing compounds generated in crushed leaves of Chinese chive (Allium tuberosum Rottler)

To characterise the composition of sulphur-containing constituents in Chinese chive (Allium tuberosum Rottler), GC–MS and HPLC analyses were carried out, using 12 varieties of Chinese origin, 4 varieties of Japanese origin and 6 commercially available cultivars. Five disulphides (dimethyl, allyl methyl, methyl 1-(E)-propenyl, diallyl, and allyl 1-(E)-propenyl), two trisulphides (dimethyl and allyl methyl), and two vinyldithiins (3-vinyl-[4H]-1,2- and 2-vinyl-[4H]-1,3-) were identified on the basis of their mass spectral and GC-retention data. Among the detected sulphur compounds, sulphides with a methyl group predominated over those with an allyl group. This was supported by the HPLC estimations, suggesting that all cultivars examined had much greater amounts of methiin than alliin. Also, two novel compounds were tentatively identified as [3H,4H]-1,2-dithiin and [2H,4H]-1,3-dithiin on the basis of their mass spectral features, GC-retention data, and some experimental results on their formation in reaction mixtures with different proportions of methiin and alliin. Their formation mechanism was proposed.     

顶空固相微萃取与气质联用法分析大葱的挥发性风味成分

本文以经过切碎和打浆两种方法处理后的新鲜大葱为研究对象，采用顶空固相微萃取和气质联用的方法测定其挥发性成分，分别分离得到了多种风殊物质。其中，经过两种处理方法后共同检测出的物质为：正丙醛，二硫化碳，二甲基二硫醚，2．甲基1-2．戊醛，甲丙基瑚啾，二-塞烷，二甲基三硫醚，十一烷，二丙基鞠隧，2-十一酮，二丙鲞三硫醚，3，5二乙基-1，2，4-三硫窥杂环戊烷，2-十三酮，N-环己基吡咯烷酮。     

Chemical and Sensory Properties of Sauerkraut Produced with Leuconostoc mesenteroides Starter Cultures of Differing Malolactic Phenotypes

ABSTRACT: Research was conducted to determine whether Leuconostoc mesenteroides starter cultures with and without malolactic activity (MDC⁺ and MDC^-, respectively) influenced sensory and chemical properties of sauerkraut. No sensory differences were found between MDC⁺ and MDC− sauerkraut ( P ≥ 0.05). In addition, sulfur compound profiles of the resulting sauerkraut were nearly identical. Brining at lower NaCl (0.5%) with either inoculum changed both the microbiology and chemistry of the fermenting sauerkraut, leading to decreased sauerkraut sulfur flavor. Quantification of allyl isothiocyanate (AITC), dimethyl disulfide, dimethyl trisulfide (DMTS), methyl methanethiosulfinate, and methyl methanethiosulfonate (MMTSO₂) by gas chromatography-mass spectrometry showed that sauerkraut sulfur flavor correlated linearly with DMTS and MMTSO₂ ( P ≤ 0.01).     

Investigation of the volatile aroma components of garlic leaves essential oil. Possibility of utilization to enrich garlic bulb oil

The volatile aroma components of Egyptian green garlic leaves essential oil was investigated for the first time. After the utilization of garlic bulbs to prepare garlic oil or after drying the bulbs to produce garlic powder, garlic leaves are considered to be waste material, which is disposed of without any benefit. In this investigation, green garlic leaves were distilled and the essential oil was subjected to GC and GC-MS identification. The yield of the oil was 0.06% (based on wet weight of the leaves). The most prominent compounds of the essential oil were diallyl trisulfide (32.32%), followed by diallyl disulfide (31.35%) and methyl allyl trisulfide (11.40%); these compounds are the same as those found in garlic bulb oil. This means that garlic leaf oil is a rich, renewable and priceless source of garlic aroma compounds which could be utilized in fortification and enriching of garlic bulb essential oil to increase its quantity without changing the quality. Utilization of green garlic leaves for production of essential oil will also save, to some extent, the costs of disposing of large amounts of leaves in garlic possessing factories, transforming them into profits.     

夏季和冬季普定县韭黄韭菜的营养与香气成分分析

为探讨普定县韭黄、韭菜的营养和香气成分的差异以及季节的影响,以期为二者的资源开发提供依据,通过国标方法测定营养成分和气相色谱-质谱联用测定香气成分。结果表明,韭黄、韭菜的营养成分有显著差异(P<0.05),主成分分析可将影响二者营养的指标归类于2个主成分。二者水分含量高达90%,夏季韭菜的粗蛋白、总糖、粗纤维和总多酚含量最高,冬季韭菜的粗脂肪、可滴定酸、维生素C的含量最高。韭黄基本营养低于韭菜,其夏季粗蛋白、总糖、维生素C、总多酚含量高于冬季,而粗脂肪、可滴定酸、粗纤维总量略低于冬季。韭菜的氨基酸价值较韭黄更高,但鲜味和甜味氨基酸呈味贡献值较低。夏季韭黄、韭菜各检出香气成分27、24种,冬季各检出16、18种,经组间联接聚类分析韭黄和韭菜气成分各聚为3类、2类,有机硫化合物是主要香气成分。韭黄中烯丙基甲基二硫醚(413.23~661.70 ng/g)、二甲基三硫(478.41~726.30 ng/g)含量最高;韭菜中烯丙基甲基硫醚(793.40~925.08 ng/g)、烯丙基甲基二硫醚(785.28~837.60 ng/g)含量最高。冬季韭菜营养价值更高,而韭黄风味更佳,受季节影响较大,该研究有助于韭菜、韭黄资源的季节性开发。     

韭菜籽挥发油组分的分析鉴定

韭菜籽挥发油中分析鉴定出的27 种成分分别占三种韭菜籽挥发油总量的92.79%、93.00% 和92.01%,其中包括7 种二硫化合物、1 种四硫化合物、3 种醛类化合物、2 种酮类化合物、3 种醇类化合物。己醛(17.74%)、十九烯-2- 酮(10.39%)和2- 戊基呋喃(6.50%)是“791”韭菜籽挥发油的主要成分。韭菜籽挥发油中含有大量的己醛,韭菜籽挥发油中含32.43% 的二硫化合物。     

Volatile constituents from Romanesco cauliflower

The volatile and semi-volatile constituents of Brassica oleracea L. var. Botrytis L., Romanesco group, Navona variety, were extracted by steam distillation from leaves and inflorescence, using a Likens–Nickerson-type apparatus. The extracts from fresh, ripening and frozen vegetables were investigated by gas chromatography and mass spectrometry. From the fresh leaves extract, a total of 61 compounds were identified, representing 96.8% of the oil. The major constituent was found to be hex-3(Z)-enol (61.1%). From fresh disrupted inflorescence tissues of Romanesco, 35 compounds were detected, representing 97.7% of the extract. Dimethyl disulfide, dimethyl trisulfide and hex-3(Z)-enol were identified as major constituents of the hydrodistillation products, representing, respectively, 30.2, 24.2 and 21.7% of the volatiles. From ripening and frozen inflorescence tissues, dimethyl disulfide and trisulfide were again detected as predominant components. In the latter, hex-3(Z)-enol had almost disappeared (0.8%) whereas dimethyl trisulfide represented 49.7% of the oil. This is the first report concerning the steam distillation compounds present in the leaves and inflorescence tissues of this species.