利用AEDA方法鉴别牛肉香精中的关键芳香化合物

GC-O(GC-olfactometry)技术是近年来国外广泛使用的一种香味分析技术,其中的稀释方法AEDA在鉴别关键芳香化合物方面具有优势。文中采用AEDA技术分析自制牛肉香精的关键芳香化合物,发现该牛肉香精香味中的绝大多数气味活性化合物在相关的牛肉香味文献中都有报道。     

Characterization of the key aroma compounds in beef extract using aroma extract dilution analysis

Aroma extract dilution analysis (AEDA) of an ether extract prepared from beef extract (BE) and subsequent identification experiments led to the determination of seven aroma-active compounds in the flavor dilution (FD) factor range of 32–128. Omission experiments to select the most aroma-active compounds from the seven aroma compounds suggested that 2,3,5-trimethyl pyrazine, 1-octen-3-ol, 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were the main active compounds contributing to the aroma of BE. Aroma recombination, addition, and omission experiments of the four aroma compounds in taste-reconstituted BE showed that each compound had an individual aroma profile. A comparison of the overall aroma between this recombination mixture and BE showed a high similarity, suggesting that the key aroma compounds had been identified successfully.     

气质联用结合主成分分析辨别卷烟基本味觉的研究

利用气相色谱质谱联用技术测定了烤烟型A、烤烟型B、混合型C、混合型D四种成品烟的主流烟气成分,利用主成分分析对烟气成分数据进行分析处理,筛选主要贡献物质,进而考察主要贡献成分与酸、甜、苦、咸四种味觉的相互关系。主成分分析结果表明,四种成品烟中,混合型C与混合型D的味觉相互接近,其他两种之间差异较大。进一步对四种成品烟进行感官评价,主要对四种味觉强度进行描述评价,结果与气质联用结合主成分分析结果基本一致,由此验证了主成分分析与气质联用结合的客观性。     

Evaluation of potent odorants in heated egg yolk by aroma extract dilution analysis

Egg yolk was extracted using the method of Likens-Nickerson (simultaneous distillation/extraction). The resulting aroma extract, which smelled characteristic of heated egg yolk was analysed by aroma extract dilution analysis and gas chromatography–mass spectrometry. Of 41 odorants that were detected, 19 could be identified. Compounds with high flavour dilution factors were methional, phenyl acetaldehyde, 2-acetyl-1-pyrroline, heptanal, 1-octen-3-one and (E,E)-2,4-decadienal. Strecker degradation of methionine, phenylalanine and proline, as well as autoxidation of phospholipid-bound linoleic and arachidonic acids are proposed as the major factors for egg yolk flavour formation.     

Comparative evaluation of potent odorants of boiled beef by aroma extract dilution and concentration analysis

 After boiling, beef was extracted with dichloromethane, and the volatile fraction including the solvent was distilled from the non-volatile material. The distillate was divided into two portions; one-half was subjected to aroma extract dilution analysis (AEDA), and the other to aroma extract concentration analysis (AECA). In the latter case, the AECA was accompanied by a series of gas chromatography-olfactometry (GCO) analyses, whereas in the former (i.e. AEDA) the extract was first concentrated to a small volume and then diluted stepwise for GCO analysis. Both screening procedures confirmed the presence of 32 odorants which were all identified after a 250-fold concentration of the extracts. However, the ranking of the compounds in order of odour potency was different due to losses of the odorants in AEDA. 2-Furfurylthiol and 4-hydroxy-2,5-dimethyl-3(2H)-furanone followed by 2-methyl-3-furanthiol and a group containing 3-mercapto-2-pentanone, 1-octen-3-one and (E)-2-non-enal were indicated by AECA to be the most potent odorants of boiled beef. Received: 15 March 1996     

非热杀菌在NFC果汁上的应用前景

为探究浓缩还原（From concentrate,FC）和非浓缩还原（Not from concentrate,NFC）杨梅汁成分的差异,本文借助超高效液相色谱-四极杆飞行时间质谱的代谢组学技术分析二者的代谢产物。通过正交偏最小二乘-判别分析实现了对NFC和FC杨梅汁的区分,根据变量投影重要度和差异倍数筛选出9个差异较大的代谢物,经对比发现,FC杨梅汁中对磺基苯甲酸、5-甲基四氢叶酸、矢车菊素、西瑞香素、花椒毒酚和异黄蝶呤等抗氧化活性成分的含量相对较低,而苦味物质（新橙皮苷、橙皮苷和槲皮素-3-O-新橙皮苷）含量相对较高。通过对差异代谢物的代谢途径分析,筛选出5条差异较大的代谢通路,其中苯丙氨酸代谢、黄酮和黄酮醇的生物合成是NFC与FC杨梅汁中差异代谢物的关键代谢途径。本研究揭示了NFC与FC杨梅汁代谢产物的差异性,为NFC杨梅汁的加工与鉴别提供理论参考。     

气相色谱-质谱联用法分析三沟白酒香气成分

目的 采用气相色谱-质谱联用技术对三沟白酒香气成分进行分析。方法 对10批三沟白酒样品经前处理后,应用色谱峰面积归一化法测定各组分的相对含量。结果 分离并鉴定了49种微量物质,包括18 种酯类成分,占所有香气物质的64.71 %;9 种酸类成分,占28.09%;15 种醇类成分,占5.04 %;4 种醛类成分,占1.82 %;2 种酮类成分占0.28%;和1 种烷烃类成分占0.06 %。相对含量较高的化合物有己酸乙酯、乳酸乙酯、乙酸乙酯、、丁酸乙酯己酸、乙酸、丁酸、乙缩醛、异戊醇和正丁醇。结论 所含主要相对含量较高的化合物,合计占总香气成分的94.16%,构成了三沟白酒主要香气成分。     

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。     

Gas chromatographic-olfactometric characterization of aroma active compounds in sun-dried and vacuum-dried tarhana

The influence of drying methods on the aroma active volatiles of sun-dried tarhana (SDT) and vacuum-dried tarhana (VDT) were compared using headspace SPME, GC-O and GC-MS. Although vacuum drying reduced the total amount of volatiles as compared to SDT (total FID peak area), more aroma active material was retained with VDT (total olfactory peak area). Vacuum drying retained a greater number of aroma active components (41) whereas the sun-dried method retained only 23. Aldehydes were the largest single class of aroma compounds in both types of tarhana: 17 in VDT and 10 in SDT. Other differentiating aroma compounds include alcohols, terpenes, and phenols such as geraniol, terpinolene, and 4-vinylguaiacol among others. A total of 22 aroma active components were present in greater amounts in the VDT versus only four aroma compounds present in greater amounts in the SDT.     

Quantitative determination of wine polysaccharides by gas chromatography-mass spectrometry (GC-MS) and size exclusion chromatography (SEC)

Wine polysaccharides play an important role on a number of technological and quality properties of wines and thus several methods have been proposed for their quantification. The present study evaluates the suitability of gas chromatography with mass spectrometry detector (GC-MS) for determining the content of wine monosaccharides and thus polysaccharide families. Factors affecting the yield of polysaccharide precipitation were firstly evaluated and the GC-MS method was characterised and compared with the previously reported GC-FID method. Repeatability and reproducibility values were similar in both methods, with values ranging from 1% to 14%. LODs obtained by MS were below 1.0 μg for all monosaccharides and LOQs were below 1.8 μg. Moreover, a recovery study of the whole method was carried out and it provided absolute recoveries between 81% and 116% for different wine samples, very good values taking into account the multi-step procedure. Both GC-MS and GC-FID were applied to determine the content of wine polysaccharide families in three wine samples and no significant differences were observed. Finally, high-resolution size exclusion chromatography with refractive index detector (HRSEC-RID) was applied to obtain the molecular weight distributions of the wine polysaccharides and to estimate their global content. The correlation observed between the polysaccharide values obtained with the GC method and the HRSEC-RID method (r = 0.746, p < 0.05) indicated that the latter could serve as a rapid and simple method to give an estimation of total wine polysaccharides although it can not be used to quantify in a precise way.     

梯度稀释法结合气相色谱-嗅闻-质谱联用仪鉴定炸花椒油中关键性香气活性化合物

采用同时蒸馏萃取和溶剂辅助蒸发提取炸花椒油中的挥发性风味成分,气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)对提取物进行定性和定量分析,梯度稀释法结合气相色谱-嗅闻(gas chromatography and olfactometry,GC-O)鉴定提取物中的关键性香气化合物。2种方法共鉴定出75种挥发性风味成分,包括烃类19种、醛类13种、醇类22种、酮类5种、酯类8种、杂环类及其他化合物8种;2种方法共检测出58个气味活性区域,从中鉴定出44种香气活性化合物,稀释因子较大(FD≥34)的芳樟醇、大根香叶烯D、柠檬烯、乙酸芳樟酯、乙酸-4-松油烯醇酯等是炸花椒油中的关键性香气活性化合物。     

GC-O-AEDA法在食品风味分析中的应用

芳香萃取物稀释分析法是气相色谱-嗅觉测量法中一种有效地利用稀释因子(FD)具体说明气味活性物质贡献大小的方法。文章介绍它的原理、主要的样品稀释方法及其所对应采用的前处理方法,并综述该技术在食品风味分析中的应用。     

红枣不同部位的脂溶性成分分析

为研究红枣的果肉、果皮和果核中脂肪酸成分,以石油醚为提取溶剂,采用索氏提取法分别对枣肉、枣皮和枣核进行提取,运用衍生化GC-MS对其成分进行了分析和鉴定。结果表明:(1)果核在红枣各部位中脂质成分的含量最高,占果核总重(13.5±3.6)%,果皮次之,占果皮总重(6.0±2.5)%,果肉最少,仅(2.4±1.5)%;(2)从枣果脂溶性物质中分离鉴定了12个化学成分,占色谱总馏分出峰面积的82.34%,从枣皮分离鉴定了9个化学组分,占总出峰面积的81.66%,从枣核中分离坚定了15个化学成分,占色谱总馏分出峰面积的59.40%;(3)红枣3个部位的脂溶性物质中均含有一定量的苯系化合物、不饱和烃、不饱和脂肪酸、饱和脂肪酸及酰胺类物质,其中枣皮部位还有较高含量的角鲨烯成分。     

Characterization of the key aroma compounds in roasted duck liver by means of aroma extract dilution analysis: comparison with beef and pork livers

By application of the aroma extract dilution analysis (AEDA) on the volatile fraction isolated by solvent extraction and solvent-assisted flavour evaporation from roasted duck liver, thirty odour-active areas could be detected in the flavour dilution factor (FD) range of 16–2,048. The highest FD factors were found for 2-acetyl-1-pyrroline (roasty, popcorn-like), 2-acetyltetrahydropyridine (roasty), and 2-acetyl-2-thiazoline (roasty), followed by 2-furfurylthiol (roasty, coffee-like) and 3-methylthio(propanal) (cooked potato) with slightly lower FD factors of 1,024. Application of the AEDA on the volatiles isolated from roasted pork and beef livers revealed basically the same set of odorants in about the same range of FD factors in both livers. A main difference, however, was the comparatively low FD factor of 2-acetyltetrahydropyridine in beef and pork livers indicating that this roasty smelling odorant might be responsible for the difference detectable in the overall aroma of duck liver. In total, 15 odorants were identified for the first time in liver.     

川藏高原不同年份霞多丽冰酒香气成分GC-MS分析

采用气相色谱质谱-联用分析法分别对2009年至2013年五个年份的川藏高原霞多丽冰酒进行了香气成分分析。结果表明,五个年份冰酒中所含的主要香气成分为酯类,醇类和酸类物质等。在2009年至2013年的冰酒中分别检测到26种、22种、53种、23种和38种香气成分。2009年冰酒中酯类10种（75.44%）,醇类6种（11.16%）,酸类3种（7.36%）和萜烯类3种（2.30%）;2010年酯类9种（74.47%）,醇类5种（14.67%）,酸类3种（6.75%）和萜烯类2种（1.94%）;2011年酯类16种（62.77%）,醇类10种（16.49%）,酸类4种（8.6%）和萜烯类3种（2.49%）;2012年酯类9种（78.8%）,醇类3种（8.92%）,酸类3种（9.16%）和萜烯类3种（1.62％）;2013年酯类14种（66.13%）,醇类4种（10.83%）,酸类4种（13.05%）和萜烯类4种（4.65%）。     

气质联用法测定卷烟侧流烟气中苯并[a]芘

建立了采用气相色谱/质谱联用法分析卷烟侧流烟气中苯并[a]芘的分析方法.该方法使用配有鱼尾罩的侧流吸烟机抽吸卷烟,鱼尾罩附着的苯并[a]芘采用甲醇洗脱,洗脱液中的甲醇在N2保护下加热至80℃挥发完,然后加入捕集了侧流烟气总粒相物的玻璃纤维滤片,采用环己烷超声萃取苯并[a]芘,萃取液苯并[a]芘浓度采用气相色谱/质谱联用...     

脐橙果汁与果酒香气成分的GC-MS分析

采用溶剂萃取法分别提取脐橙果汁和经发酵后的果酒中的香气成分,经气相色谱质谱联用仪(GC-MS)分析,从果汁中鉴定出19种成分,占峰面积的83.5％,香气成分主要为苯乙醇、4-羟基-苯乙醇3-甲基-1-丁醇、D-柠檬烯、2,3丁二醇、巴伦西亚桔烯、亚油酸、油酸等:从果酒中鉴定出30种成分,占峰面积的91.13％,主要香气成分为苯乙醇、3-甲基-1-丁醇、d-柠檬烯、2,3丁二醇、乙酸乙酯、香叶醇、棕榈酸乙酯、3-乙氧基-1-丙醇、巴伦西亚桔烯、吲哚-3-乙醇、乙酸戊酯等.