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 )。     

豆汁的风味物质分析

为了研究老北京豆汁中的风味物质,采用SPME法处理3种市售成品豆汁以及自制的不同发酵时间的豆汁样品,用GC-O-MS联用法对其风味物质定性分析。结果表明,从市售豆汁中分析出14种醇,5种醛,3种酸,2种醚,1种酚,1种酯;二甲基二硫醚、乙醇、乙酸、丙酸等物质具有豆汁的典型气味。从自制不同发酵时间的豆汁中分析出10种醇,3种醛,2种酮,5种酸,3种醚,1种酚,3种酯,1种烯烃。与市售成品豆汁相比,自制豆汁中甲硫醇、二甲基二硫醚、正戊醇、二甲基三硫醚、乙酸、丙酸、4-乙基-苯酚、丁酸始终存在,其他挥发性风味成分在发酵的不同阶段显示不同的存在规律。     

顶空固相微萃取气质联用分析香葱挥发性风味成分

采用顶空固相微萃取气质联用分析检测了香葱的挥发性风味成分,共检测到30种化合物,占总峰面积的98.18%。主要成分是二丙基二硫醚(31.94%)、二丙基三硫醚(16.4%)、1-丙硫醇(11.27%)、二甲基硫醚(10.36%)、甲基-2-丙烯基二硫(6.11%)、1-丙烯-1-甲基硫醇(3.49%),占总成分的79.57%。     

基于电子鼻和气相色谱-质谱法结合相对气味活度值分析植物油对红油辣椒气味的影响

目的 为探究植物油对红油辣椒气味的影响。方法 采用电子鼻、气质联用技术(gas chromatography-mass spectrometry,GC-MS)结合正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)和相对气味活度值(Relative Odor Activity Value,ROAV)等分析方法探究不同品种的植物油对红油辣椒气味物质的影响。结果 电子鼻检测结果结合OPLS-DA分析表明不同品种的植物油制备的红油辣椒其整体气味轮廓差异明显。GC-MS检测结果表明5种植物油制备的红油辣椒共检测到101种挥发性物质,其中醇类29种、醛类30种、烃类12种、硫醚类3种、酯类6种、酸类2种以及其他化合物19种；醇类、醛类、硫醚类是红油辣椒的主要挥发性物质。ROAV分析表明A样品(精炼菜籽油)的关键性化合物是：苯乙醛、反-2-壬醛、二甲基硫醚；B样品(大豆油)的关键性化合物是：1-庚烯-3-酮、二甲基硫醚；C(花生油)、E(菜籽油)样品的关键性化合物是：二甲基硫醚; D(玉米油)样品的关键性化合物是：二甲基硫醚、(Z)-2-壬烯醛、1-辛烯-3-酮。结论 不同品种的植物油制备的红油辣椒的主要挥发性物质有一定差,二甲基硫醚是红油辣椒的共有关键性化合物。     

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%。     

同时蒸馏萃取- 气质联机分析腌渍野韭菜花香成分

以乙醚为溶剂,采用同时蒸馏萃取法提取腌渍野韭菜花精油,提取率0.29%。用气相色谱- 质谱法结合气相色谱保留指数定性方法,从腌渍野韭菜花精油中鉴定出37 种挥发性成分,占精油总成分的95.75%。主要成分为二甲基三硫醚(28.18%)、二甲基二硫醚(18.13%)、甲基丙烯基二硫醚(14.24%)、甲基烯丙基三硫醚(4.89%)、甲基烯丙基二硫醚(3.19%)、甲基甲硫基甲基二硫醚(3.10%)、4- 乙烯基愈创木酚(2.93%)、二烯丙基二硫醚(2.71%)、二甲基四硫醚(2.67%)、3- 羟基-2- 丁酮(2.42%)、2- 乙烯基-2- 丁烯醛(1.54%)、2,5- 二甲基-1,3,4- 五硫三环(1.45%)、苯甲醇(1.31%)和甲硫基甲磺酰基甲烷(1.28%)等。其中硫醚和多硫醚类成分11 种,相对含量79.99%,是腌渍野韭菜花的特征香气成分。     

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。     

清炖猪肉汤香气物质的分析鉴定

对实验所用猪肉的氨基酸组成及脂肪酸组成进行分析。将猪肉清炖3 h的肉汤,采用溶剂辅助蒸发提取,气相色谱-质谱联机分析,通过谱库检索和保留指数核对,鉴定出70种化合物;进一步采用稀释法-气相色谱-嗅闻分析,结合保留指数、气味特征及与标准品比对,鉴定出24种香气活性物质。所鉴定的气味活性化合物主要为脂肪族的醛类、酮类、醇类及含硫化合物,稀释因子较高的(log2FD≥9)有庚醛、壬醛、(E)-2-壬烯醛、(E,E)-2,4-癸二烯醛、2-十一酮、3-羟基-2-丁酮、3-(甲硫基)丙醛、糠硫醇、二甲基三硫醚、2-噻吩硫醇、双(2-甲基-3-呋喃基)二硫醚、1-辛烯-3-醇、γ-癸内酯。     

腌制对大蒜挥发性风味物质以及生物活性物质的影响

为了解腌制方式对大蒜中挥发性风味物质及生物活性物质的影响,采用气相色谱和离子迁移谱联用技术对不同腌制方式的大蒜样品中挥发性物质进行采集和分析,采用高效液相色谱法检测蒜氨酸含量,采用植物蒜氨酶酶联免疫分析试剂盒检测蒜氨酸酶浓度活性。结果表明,不同腌制方式的大蒜样品中均鉴定出39种挥发性物质,包括含硫化合物(9种)、酯类(10种)、醛类(5种)、酮类(6种)、醇类(2种)、酚类(1种)、酸类(1种)及其他类(5种)。四川坛泡咸大蒜的特征风味物质有己酸乙酯(M)、己酸乙酯(D)、2-癸烯醛、2,3-二乙基-5-甲基吡嗪、乙酸异戊酯、惕各酸乙酯、2-戊基呋喃、2-甲基丁酸乙酯、2,3-戊二酮、甲基吡嗪、3-苯丙酸乙酯、羟基丙酮、2,6-二甲基-4-庚酮、3-己烯酸乙酯、2,4,5-三甲基噻唑(D)、2,4,5-三甲基噻唑(M)、2-丁酮。腊八蒜的特征风味物质有二丙基二硫、苯甲醛、2-戊酮、己醛(M)、己醛(D)、2-庚基呋喃、二烯丙基三硫、2(3H)-二氢呋喃酮、二甲基三硫、E-2-庚烯醛(M)、E-2-庚烯醛(D)、戊酸乙酯(D)、戊酸乙酯(M)、糠醛。糖醋蒜的特征风味物质有二烯丙基硫醚、二...     

不同发酵方式盐渍萝卜挥发性成分动态分析

以不同发酵方式盐渍萝卜为研究对象,分析发酵过程中挥发性成分及其差异性。制备水分活度为0.95、0.90和0.85的盐渍萝卜模拟湿态、半干态和干态工艺,采用顶空固相微萃取-气相色谱-质谱联用法分析不同发酵方式盐渍萝卜发酵过程中挥发性风味成分变化,结合多元统计方法分析盐渍萝卜的主成分及特征挥发性成分。结果表明,湿态盐渍萝卜以乳酸菌为主导发酵,半干态和干态盐渍萝卜微生物影响较小,其发酵程度弱或不发酵。3种不同发酵方式的盐渍萝卜发酵30 d共分析出挥发性风味物质61种,基于主成分分析发现4-异硫代氰酸甲基戊酯、己醇、癸醛、壬醛、二甲基四硫醚、3-羟基-2-丁酮、1-辛烯-3-醇、1-异硫代氰酸己酯、3,5-辛二烯-3-酮、4-仲丁基苯酚、1-庚醇和顺-2-戊烯醇为正影响挥发性物质的典型代表。采用偏最小二乘法判别分析和层次聚类方法筛选出重要度(VIP1.2)以及t检验(P0.05)的挥发性特征成分12种。其中乙酸为湿态盐渍萝卜特征性成分;1-戊烯-3-醇、顺-2-戊烯醇、1,1-二(甲硫基)乙烷和甲氧基苯肟为半干态盐渍萝卜特征性成分;己酸、二甲基三硫醚、3-羟基-2-丁酮、2-正戊基呋喃、二甲基四硫醚、庚醛和苯乙醇为干态盐渍萝卜特征性成分。这些特征挥发性风味成分有助于区分3种发酵方式盐渍萝卜的工艺特性和发酵状态。研究结果为提升盐渍萝卜风味品质提供一定的理论依据。     

6类常见食品中含硫化合物风味特征及形成机理研究进展

挥发性含硫化合物广泛存在于多种食品中,具有阈值极低的特点,是对食品感官品质有重要贡献的特征风味组分,在形成食品独特风味特征中也起着至关重要的作用。不同种类的含硫化合物表现出的食品风味特征不尽相同,不同含量的含硫化合物对食品感官品质的影响也差异显著,因此,对感官风味受含硫化合物影响较大的6类常见食品中含硫化合物风味特征及其形成机理进行了研究。牛奶中主要含硫化合物是甲硫醇和二甲基三硫醚,通常表现为蒸煮味;2-甲基-3-呋喃硫醇是牛肉的关键含硫化合物,呈现为焙烤香和肉香;糠硫醇的焙烤香、3-巯基己烷-1-醇的果香是酒类中的关键风味组分;1,2,3,5,6-五硫杂环庚烷是呈现香菇独特气味的关键化合物;二丙基二硫醚、二甲基三硫醚和大蒜素分别为大葱、洋葱和大蒜风味形成的关键含硫化合物;二甲基硫醚和二甲基三硫醚是菜籽油呈现辛辣刺激风味的主要原因。含硫化合物主要是由含硫前体物质在微生物或酶的降解作用下形成,同时有些含硫化合物也产生于美拉德反应。通过对6类常见食品中含硫化合物的种类、对食品感官品质的影响及其形成机制进行全面介绍,总结常见食品中含硫化合物的风味及其对食品感官品质影响的一般规律,旨在为食品中含硫化合物形成机理及风味特征的进一步研究提供参考。     

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.     

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.     

Involvement of Volatile Sulfur Compounds in Ionizing Radiation-induced Off-odor of Fresh Orange Juice

ABSTRACT: The influences of ionizing radiation on volatile sulfur compounds in fresh Valencia orange juice were analyzed using gas chromatography (GC)-pulsed flame photometric detection and sensory evaluation. Methyl sulfide (MS) and methanethiol (MT) were induced most, followed by dimethyl disulfide and dimethyl trisulfide. Carbon disulfide was reduced by irradiation, while hydrogen sulfide was not consistently affected. Sensory evaluation indicated that the odor of irradiated juice differed from the nonirradiated samples at 0.5, 1, 2, or 3 kGy. Addition of the 2 major irradiation-induced sulfur compounds (MS and MT) into fresh juice changed the juice odor, indicating that those 2 compounds were probably involved in the development of irradiation-induced off-odor.     

Transfer of the Meat Aroma Precursors (Dimethyl Sulfide, Dimethyl Disulfide and Dimethyl Trisulfide) from Feed to Cooked Pork

Eight pigs were given standard concentrate feed to a live weight of 70 kg. Subsequently half the pigs were controls and were fed the concentrate feed, while the other half of the pigs were fed an experimental diet consisting of the concentrate feed (89 percent of calories) and Brussels sprouts (11 percent of calories) the last 4 weeks before slaughter. Analyses of volatiles in chops and gastro-intestinal contents were performed using solid-phase micro extraction and subsequent characterization by gas chromatography-mass spectrometry. The ratio between the amount of dimethyl sulfide found in the stomach contents from pigs fed Brussels sprouts and the stomach contents from pigs fed the control diet was 9.0, and correspondingly the ratio was 475.5 for dimethyl disulfide and 8.3 for dimethyl trisulfide. The ratio between the amount of dimethyl sulfide found in meat from pigs fed Brussels sprouts and meat from pigs fed the control diet was 14.9, and correspondingly the ratio was 4.8 for dimethyl disulfide and 1.9 for dimethyl trisulfide. Moreover, several other compounds seem to be influenced by feed composition. Finally, the increase in concentration of sulfur compounds in meat in relation to pork aroma is discussed.     

Changes in Volatile Sulfur Compounds of Whisky During Aging

Volatile sulfur compounds of malt whiskies were analyzed using a gas chromatograph equipped with a flame photometric detector by direct injection and solvent extraction methods. Sulfur compounds identified by coupled gas chromatography-mass spectrometry and by matching GC retention times were dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, 3-(methylthio)propanal, 3-(methylthio)propanol, 3-(methylthio)propyl acetate, ethyl 3-(methylthio)-propanoate, dihydro-2-methyl-3(2H)-thiophenone, 2-thiophene-carboxyaldehyde, 5-methyl-2-thiophenecarboxaldehyde, benzothiophene and benzothiazole. Quantitative changes in these volatile sulfur compounds were studied by analyzing 48 aged and unaged malt whiskies by these methods. Dimethyl sulfide, 3-(methylthio)propyl acetate, dihydro-2-methyl-3(2H)-thiophenone and ethyl 3-(methylthio)propanoate decreased rapidly during aging and disappeared within three years. Dimethyl disulfide decreased gradually during aging. Dimethyl disulfide proved to be formed during distillation by the action of copper.     

冷藏小黄鱼优势腐败菌致腐能力评价及其对挥发性成分的影响

为探究不同优势腐败菌(Specific spoilage organisms,SSOs)的致腐能力及其对水产品挥发性成分的影响,本文以小黄鱼为原料,通过接种优势腐败菌,测定其挥发性盐基氮值(TVB-N)、菌落总数和挥发性成分含量。结果表明,变形杆菌属(Proteus hauseri)致腐能力与希瓦氏菌属(Shewanella glacialipiscicola)相当,且强于普罗威斯登菌属(Providencia heimbachae);3种优势腐败菌作用下挥发性成分主要为醇类、酯类、烃类以及含氮含硫物,其中气味的主要贡献物质为吲哚、三甲胺、二甲基二硫和二甲基三硫,S.glacialipiscicola产生的气味物质量最大,P.hauseri次之,P.heimbachae最少;优势腐败菌的产量因子与对应的含氮含硫挥发物含量变化具有一致性,相关性研究进一步显示,吲哚、三甲胺、二甲基二硫和二甲基三硫含量与TVB-N含量呈显著相关(p<0.05)。