酸桔果皮油的特征香气成分

为评价酸桔果皮的特征香气成分,先用同时蒸馏与萃取法(SDE)提取酸桔果皮的精油,并用硅胶柱将精油分成碳氢化合物和含氧化合物两大部分.含氧化合物部分具有果皮油的特征香气,用GC/MS对该部分进行了分析,鉴定出56种含氧化合物成分,然后用GC-Sniffing方法评价了酸桔果皮油的特征香气成分,明确了顺式氧化沉香醇、沉香醇、顺式氧化柠烯、香茅醛、香茅醇、香芹酮以及一些脂肪族醛等12种成分对酸桔果皮的香气影响.用这些成分按适当比调配成的混合液基本上能够代表原果皮的香气.     

白柠檬果皮油的挥发性成分

∶以溶剂萃取法从白柠檬果皮提取精油,并用硅胶柱将精油分成碳氢化合物和含氧化合物两大部分． 利用气相色谱和质谱联用系统测定了白柠檬果皮油的香气成分,并依据各成分的保留指数,鉴定出７５种挥发性成分． 其中有２３种碳氢化合物、１２种醇类物质、１７种醛类物质、１１种酯类物质、２种酚类物质、２种醚类物质和８种酮类物质．     

套袋对柠檬香气成分的影响

为了研究套袋技术对柠檬香气的影响,以套袋安岳柠檬的果皮果肉为研究对象,未套袋柠檬为对照,采用顶空固相微萃取-气相色谱-质谱联用技术测定果皮和果肉香气成分,检出主要香气成分的相对含量从高到底依次为烯烃类、醇类、醛类、酯类和酮类等物质。结果表明:无论是否套袋,果皮始终比果肉的香气组分更加丰富,柠檬香气品质主要体现在果皮上;与对照相比,套袋后柠檬果皮果肉香气的主要组分仍保持基本一致;套袋后含氧萜类成分的相对含量减少,减少量均低于2.91%,套袋降低柠檬的香气品质,但降低程度不大。柠檬醛是柠檬中最重要的香气成分,两种同分异构体(橙花醛和香叶醛)的含量比很稳定,果皮中约2:3,果肉中约1:2。     

GC—MS分析柠檬不同品种果皮精油成分

以云南德宏地区栽培的不同柠檬品种为试材,利用气质联用技术（GC-MS）分析果皮精油挥发性成分种类及相对含量,比较不同品种挥发性成分差异。结果表明,费米耐劳、云柠1号、艾伦尤力克柠檬果皮精油中分别检测到23、20、27种挥发性成分,烯烃类、醇类、醛类、酯类和酮类是3个品种共有组分。烯烃类物质是主要组分,其中特征香气成分D-柠檬烯含量最高,β-蒎烯、γ-萜品烯次之。艾伦尤力克柠檬中挥发性物质的种类和含量均高于费米耐劳和云柠1号柠檬,主要特征香气成分含量也最高。     

不同成熟阶段柠檬果皮挥发物和酚类成分分析

为探究柠檬果皮香气和酚类成分在不同成熟阶段的变化特点,以抗病品种香水柠檬和泰吹柠檬不同成熟阶段果皮为材料,采用顶空固相微萃取结合气相色谱-质谱法分析其挥发物成分,高效液相色谱法测定其酚类成分。结果表明：2 个品种柠檬果皮中共检测到86 种挥发性成分,以萜烯类、醛类和醇类为主,香水柠檬果皮中倍半萜和醛类含量较高,泰吹柠檬果皮中单萜和醇类含量较高。香水柠檬果皮中单萜、倍半萜、醛类的含量在成熟期间发生显著变化,其中单萜、倍半萜含量均呈先下降后上升再下降的趋势,醛类含量呈上升趋势;泰吹柠檬果皮中单萜、醇类和醛类的含量在成熟期间发生显著变化,3 类香气物质的含量均呈先下降后上升的趋势。根据香气成分的香气值,香水柠檬和泰吹柠檬果皮中分别鉴定出26 种和22 种特征香气成分。在整个发育期中,对香水柠檬香气贡献最大的特征香气成分为癸醛、十二醛、香叶醛、芳樟醇和橙花醛,对泰吹柠檬香气贡献最大的特征香气成分为癸醛、芳樟醇、香茅醛、β-月桂烯和乙酸香茅酯。香水柠檬和泰吹柠檬果皮中分别检出12 种和15 种酚类物质,2 个品种柠檬果皮中酚酸总量无显著差异,泰吹柠檬果皮中类黄酮总量显著高于香水柠檬,其中泰吹柠檬果皮中多甲氧基黄酮总量为香水柠檬的20.94～118.75 倍。果实成熟对香水柠檬和泰吹柠檬果皮中酚酸总量和类黄酮总量有显著影响,随成熟度提高,2 个品种酚酸总量和类黄酮总量均呈下降趋势。研究结果为柠檬果实资源的利用和抗病种质创新提供支撑。     

柠檬果皮精油挥发性成分的GC-MS分析

采用水蒸气蒸馏法(SD)与有机溶剂萃取法分别提取干、鲜柠檬果皮的精油,通过气相色谱和质谱联用仪测定了柠檬果皮精油的挥发性成分.结果显示:较简单的有机溶剂萃取法更有利于果皮精油挥发性成分的保留,依据化合物的质谱特性鉴定出柠檬果皮油里含有72种挥发性成分.柠檬果皮精油的主要成分为柠檬烯,含量在50%以上.     

木姜子香气成分与生物活性及其代谢途径的研究进展

木姜子作为一种药食两用的香辛料,具有较强的抗菌、抗炎、抗癌等功效,其强烈的柠檬香气,可以去腥增香提味。萜类化合物是木姜子的主要香气成分,以柠檬醛为代表的萜类化合物具有显著的生物活性。木姜子中的关键香气成分包括D-柠檬烯、(Z)-3,7-二甲基-2,6-辛二烯醛、(E)-3,7-二甲基-2,6-辛二烯醛、β-月桂烯、(E)-肉桂酸乙酯和β-石竹烯等。本文主要综述了木姜子在中国的种群分布、香气成分与生物活性的研究进展,以及主要萜类化合物在植物体内的代谢途径,以期对木姜子的资源开发和高附加值利用提供科学依据。     

青柠果皮精油蒸馏工艺优化及香气成分分析

目的:研究青柠果皮精油提取工艺及性质,为青柠果皮的综合利用提供数据。方法:以青柠果皮为原料,通过压榨法提取其精油粗产品,后经分子蒸馏技术对其进行分离纯化,以总轻馏分得率为指标,考察蒸馏温度、刮板转速、进料速度、蒸馏压力4个单因素对青柠果皮精油提取的影响,通过正交实验优化青柠果皮精油提取工艺,并用气质联用仪(GC/MS)分析青柠果皮精油香气成分组成。结果:青柠果皮精油的最佳提取工艺:蒸馏温度30℃,刮板转速400 r/min,进料速度0.25 L/h,蒸馏压力15 Pa,其总轻馏分得率为76.10%±0.29%;GC/MS结合保留指数对纯化青柠果皮精油进行香气成分分析,共鉴定55种化合物,主要包括柠檬烯(36.585%)、γ-松油烯(12.077%)、α-松油醇(8.407%)、萜品油烯(7.867%)、α-松油烯(5.777%)等。结论:优化了分子蒸馏提取青柠果皮精油工艺,并从香气成分中鉴定出55种化合物。     

锦橙果肉和果皮中游离态和键合态香气物质研究

以锦橙为研究对象,应用AmberliteXAD-2吸附和溶剂洗脱分离锦橙果肉和果汁中游离态和糖苷键合态的芳香化合物,并采用GC-MS检测了锦橙果肉和果皮中的芳香物质。结果表明,锦橙果肉中检出游离态香气31种,键合态香气21种,锦橙果皮中检出游离态香气33种,键合态香气29种。果肉和果皮中游离态和键合态香气组分的构成差别较大,果肉中主要为正己醇、3-羟基己酸乙酯、丁酸乙酯、癸醛和异环柠檬醛等;果皮中则主要为芳樟醇、反金合欢醇、δ-杜松烯、柠檬醛和榄香醇等。     

三种晚熟甜橙冷磨精油挥发性及主体香气成分的比较分析

为研究重庆主栽晚熟甜橙精油的挥发性及主体香气物质的组成含量特点,采用顶空固相微萃取-气质联用技术和香气活度值(odor activity values,OAV)分析奥林达夏橙、五月红甜橙和晚熟血橙的果皮冷磨精油(cold-pressed oil,CPO)。3个品种中分别鉴定出53、54和52个挥发性物质,其中D-柠檬烯含量普遍较低;奥林达CPO醇酚类、醛酮类含量更高,五月红和晚熟血橙CPO含较高的萜类物质。OAV分析表明,3种CPO的主体香气贡献物质包括对伞花烃、癸醛、己醛、壬醛和芳樟醇等30个成分,体现柑橘香、花香、油脂香等8类主要香气属性;奥林达CPO中花香、脂香和甜香类物质OAV较高,晚熟血橙CPO中松香和木香类物质OAV较高。本地区3个晚熟甜橙冷磨油的主体香气属性各具特点,适合加工不同类型的低萜精油,提升晚熟甜橙的产品附加值。     

Characterization of the Key Aroma Compounds of Citrus flaviculpus Hort. ex Tanaka by Aroma Extraction Dilution Analysis

ABSTRACT: The key aroma compounds were identified in Citrus flaviculpus Hort. ex Tanaka (ki-mikan) by using aroma extraction dilution analysis (AEDA) and the sniff test. Ki-mikan peel oil was extracted by cold-pressing. The highest flavor dilution (FD) factor was found for limonene. β-Phellandrene, carvacrol, spathulenol, camphene, elemol, (+)- trans -limonene oxide, and tetradecane showed higher relative flavor activity. Results of the sniff test of the original essential oil and its oxygenated fraction revealed that tetradecane, linalool, and α-terpineol were regarded as the key aroma compounds of ki-mikan peel oil. A diluted solution of linalool and α-terpineol of 3 ppm gave a ki-mikan-like flavor, while a higher concentration near 100 ppm of tetradecane tended to produce a fresh and fruity aroma note similar to ki-mikan flavor.     

气色谱-质谱/嗅觉检测联用分析九制陈皮腌制存放过程中香气成分的变化

研究九制陈皮腌制存放过程中香气成分的变化，为九制陈皮腌制存放工艺和质量控制提供依据。本研究以未腌制干燥柑桔皮（原料）及腌制后不同存放时间点九制陈皮为样品，采用气相色谱-质谱/嗅觉检测联用（GC-O/MS）对九制陈皮腌制存放过程中的挥发性成分进行分析鉴定，并结合相对气味活度值进行统计分析。共检测出58种挥发性成分，相对含量超过1%的化合物有6种。主要为烯烃类化合物，有38种，其中相对含量最高的为D-柠檬烯，最高达81.84%。存放至8个月时，挥发性化合物种类最少。随着九制陈皮风味形成，不同化合物对风味的贡献有较大变化。有香气特性的化合物有25种，关键性风味化合物有12种。醛类、酚类和烯烃类化合物对风味的贡献较大。存放至7个月时关键性风味物质种类最少，仅5种。研究表明九制陈皮腌制前后主要挥发性成分为D-柠檬烯，挥发性风味物质在腌制存放过程中物质种类和含量均有一定变化。     

Characterisation of the key aroma compounds in the peel oil of Pontianak oranges (<Emphasis Type="Italic">Citrus nobilis</Emphasis> Lour. var. <Emphasis Type="Italic">microcarpa</Emphasis> Hassk.) by aroma reconstitution experiments

Nineteen odour-active compounds previously identified with high Flavour Dilution factors in an extract from the peel oil of Pontianak oranges (Citrus nobilis Lour. var. microcarpa Hassk.) were quantified using stable isotope dilution assays (SIDA). For this purpose, four new SIDA were developed, i.e. for the quantification of (E)-2-dodecenal, geraniol, nerol, and 1-phenylethanethiol. The results showed that (R)-limonene, myrcene, and (R)-α-pinene were the predominant compounds present in concentrations between 0.4 and 60 mg/g peel. An aroma recombinate containing the nineteen aroma compounds in the concentrations naturally occurring in the peel oil elicited the overall aroma of the peel oil itself, thus confirming the identification experiments. Furthermore, omission experiments showed that the unique odour quality of the peel is significantly influenced by the resinous, sulphurous-smelling 1-phenylethanethiol, although its concentration was only 38 ng/g peel.     

Characterization and discrimination of premium‐quality,waxy, and black‐pigmented rice based on odor‐active compounds

BACKGROUND: Odor‐active compounds have been studied in cooked aromatic rice, but not in specialty rice types that have distinctly different flavors. We analyzed the odor‐active compounds emanating from three different types of specialty rice (premium‐quality, waxy and black‐pigmented) and identified the differences in odor‐active compounds among them. RESULTS: Twenty‐one, 21 and 23 odorants were detected using GC‐O for cooked samples of premium‐quality, waxy and black‐pigmented rice cultivars, respectively. Hexanal was the main odorant in premium‐quality and waxy cultivars; however, waxy cultivars had 16 times higher hexanal odor activity values (OAVs) than premium‐quality cultivars, indicating premium‐quality rice had a less pronounced overall aroma. 2‐Acetyl‐1‐pyrroline was the main contributor to overall aroma in black‐pigmented rice, followed by guaiacol. The three types of specialty rice were clearly discriminated based on the OAVs of their odor‐active compounds using multivariate analyses. Six odor‐active compounds [2‐acetyl‐1‐pyrroline, guaiacol, hexanal, (E)‐2‐nonenal, octanal and heptanal] contributed the most in discriminating the three types of specialty rice. Six very similar superior cultivars of premium rice could likewise be readily separated using aroma chemistry. CONCLUSION: The ability to discriminate the aroma among rice types using the OAVs of the principal odor‐active compounds facilitates our understanding of the aroma chemistry of specialty rice. Copyright © 2010 Society of Chemical Industry     

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。     

Fresh squeezed orange juice odor: a review

Fresh orange juice is a highly desirable but unstable product. This review examines analytical findings, odor activity, and variations due to cultivar, sampling methods, manner of juicing, plus possible enzymatic and microbial artifacts. Initial attempts to characterize orange juice odor were based on volatile quantitation and overemphasized the importance of high concentration volatiles. Although over 300 volatiles have been reported from GC-MS analytical studies, this review presents 36 consensus aroma active components from GC-olfactometry studies consisting of 14 aldehydes, 7 esters, 5 terpenes, 6 alcohols, and 4 ketones. Most are trace (microg/L) components. (+)-Limonene is an essential component in orange juice odor although its exact function is still uncertain. Total amounts of volatiles in mechanically squeezed juices are three to 10 times greater than hand-squeezed juices because of elevated peel oil levels. Elevated peel oil changes the relative proportion of several key odorants. Odor active components from solvent extraction studies differ from those collected using headspace techniques as they include volatiles with low vapor pressure such as vanillin. Some reported odorants such as 2,3-butanedione are microbial contamination artifacts. Orange juice odor models confirm that fresh orange aroma is complex as the most successful models contain 23 odorants.     

Elucidation of key aroma enhancement in cloudy lemon juices by the addition of peel oil using GC–MS-Olfactometry

Volatile substances play a crucial role in the consumer preference of lemon juices. The effects of heat treatment and addition of lemon peel oil to lemon juice (Citrus limon Burm. cv. Kutdiken) on the aroma compounds were elucidated for the first time. Total phenolic, antioxidant activity, acidity, pH and colour properties were also studied. Results revealed that the aroma of the juice samples comprised mostly the terpene compounds. Limonene, γ-terpinene, β-pinene and α-pinene were the influential terpenes responsible for the distinctive odour of the lemon juice. The addition of the lemon peel oil increased the amounts of the aroma and aroma-active compounds. Besides, the heat treatment had a positive effect on the total phenolics and the antioxidant activity but it caused significant reduction of the aroma compounds. Sensory analysis revealed that the most preferred sample was the juice with lemon peel oil added after pasteurisation.     

A comparison of the peel oil components of Australian native lime (Microcitrus australe) and Mexican lime (Citrus aurantifolia Swingle)

The essential oil components extracted from the pericarp layer of two varieties of lime fruit, viz. Mexican lime (Citrus aurantifolia Swingle) and an Australian native lime (Microcitrus australe) have been analysed by gas chromatography/mass spectrometry. Thirty‐three components were identified in M australe and 34 in C aurantifolia. The compound types comprised monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes and coumarins. For the more volatile monoterpenoid compounds, the major component was limonene, with significant amounts of γ‐terpinene, β‐pinene, geranial, neral, neryl acetate and geranyl acetate. From an examination of the nature and contents of individual components, there was no indication that any one compound might be responsible for the predominant aroma impact. The possible contribution to aroma differences due to quantitative differences in the amounts of these components is discussed. However, sensory evaluation indicated that there was little or no difference between the aromas of the two oils. Copyright © 2004 Society of Chemical Industry