共查询到17条相似文献，搜索用时 123 毫秒
1.
番薯藤挥发性化学成分的分析 总被引：2，自引：0，他引：2
采用同时蒸馏萃取法对番薯藤幼苗和成熟番薯藤的挥发性成分进行了提取,用GC/MS方法对挥发性成分进行了鉴定,从幼番薯藤中鉴定了28种化学成分,从成熟的番薯藤中鉴定了26种成分,两者成分上有较大差异. 相似文献
2.
将超声雾化作用与固相微萃取技术相结合,应用于提取蜂蜜中的挥发性成分,采用GC/MS方法进行分离、鉴定.实验结果表明,DVB/CAR/PDMS萃取纤维头富集出蜂蜜中22种挥发性化合物,且该方法简便快速,无需加热,适用于蜂蜜中挥发性成分的分析. 相似文献
3.
介绍了食品中挥发性风味的感官评价技术及指纹分析技术,食品中挥发性成分分析前处理的溶剂萃取法、同时蒸馏萃取法、固相微萃取法,挥发性成分的气相色谱一质谱定性定量分析法及气味活性成分的气相色谱一嗅闻法和气味活性值法,并对各种方法的优缺点进行了比较。 相似文献
4.
采用固相微萃取法和水蒸气蒸馏法提取白胡椒中挥发性化学成分,用气相色谱．质谱法确定挥发性化学成分结构及各化学成分在挥发油中的质量分数．分别鉴定出22种和24种化学成分．两种方法提取白胡椒挥发油中蒎烯、蒈烯、3,7-二甲基1,6-辛3-醇和石竹烯的含量均较高． 相似文献
5.
采用固相微萃取法和水蒸气蒸馏法测定姜黄中挥发性组分,测得用水蒸气蒸馏方法提取的姜黄挥发油含量3.81％.用GC/MS法从姜黄挥发油中分离并确定出30种化学成分,用固相微萃取法测定出21种化合物,并用峰面积归一化法得出各类化学成分在挥发油中的相对百分含量. 相似文献
6.
报道了用固相微萃取法（ SPME）和水蒸汽蒸馏萃取法（ DE）提取白茶中挥发性物质,并用气相色谱-质谱联用方法对其挥发性化学成分进行分析．固相微萃取法分离并确定出35种化学成分,其中主要化学成分为苯甲醛（5．91％）﹑苯乙醇（5．46％）和芳樟醇（9．02％）．水蒸汽蒸馏萃取法分离并确定出39种化学成分,其中主要化学成分为苯甲醇（5．56％）﹑苯乙醇（8．22％）和芳樟醇（5．69％）． 相似文献
7.
利用顶空固相微萃取技术,采用气相色谱-质谱法（GC/MS）对山东金银花挥发组分的化学成分进行了研究.结果：从山东干燥金银花中分析鉴定出了21种挥发性化学成分,并测定了各成分在挥发油中的百分含量,测得其中茴香精含量较高. 相似文献
8.
刺芫荽挥发性成分研究 总被引：1，自引：0，他引：1
以野生刺芫荽为原料,采用同时蒸馏萃取法提取其挥发性成分,应用气相色谱—质谱法对提取物进行化学成分分析.实验结果表明,野生刺芫荽提取物中共鉴定出24种化合物,占总峰面积的65.94％,质量分数达到1.00％以上的有6种物质,其挥发性成分中醛酮类化合物相对质量分数达到58.05％. 相似文献
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10.
白茶挥发性成分的固相微萃取-气相色谱-质谱分析 总被引：2，自引：0，他引：2
报道了用固相微萃取法提取白茶中挥发性化学成分,用气相色谱-质谱法从白茶挥发油中分离并确定出36种化学成分,其中主要成分为苯甲醛（5.91%）、苯乙醇（5.46%）、芳樟醇（9.02%）. 相似文献
11.
Guo-hua Zhang Tao Wu Faizan A. Sadiq Huan-yi Yang Tong-jie Liu Hui Ruan Guo-qing He 《Journal of Zhejiang University. Science. B》2016,17(10):787-797
Aroma of Chinese steamed bread (CSB) is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB still remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction (SPME), simultaneous distillation-extraction (SDE), and purge and trap (P&T). All samples showed a unique aroma profile, which could be attributed to their unique microbial consortia. (E)-2-Nonenal and (E,E)-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and P&T. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies. 相似文献
12.
Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous distillation and extraction (SDE). Temperature and pressure for the SFE were optimized. The extracts obtained by the two methods showed different characters in composition and represented differently the flavor characteristics of tobacco; compared to SDE, SFE can extract compounds within a shorter time and avoid the thermal degradation and solvent contamination of samples. The extracts by the two extraction methods are complementary for investigating the flavor characteristic of tobacco products. 相似文献
13.
Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous distillation and extraction (SDE). Temperature and pressure for the SFE were optimized. The extracts obtained by the two methods showed different characters in composition and represented differently the flavor characteristics of tobacco; compared to SDE, SFE can extract compounds within a shorter time and avoid the thermal degradation and solvent contamination of samples. The extracts by the two extraction methods are complementary for investigating the flavor characteristic of tobacco products. 相似文献
14.
采用同时蒸馏萃取法提取牡丹皮中的挥发油,通过GC-MS对其化学成分进行分析.结果显示挥发油中含有20个化合物,鉴定出20个.挥发油中芍药醇含量最多,其次是油酸和棕榈酸. 相似文献
15.
SPME／GC—MS法分析柠檬草挥发气体成分 总被引：1，自引：0，他引：1
利用固相微萃取SPME／GC—MS技术分析了柠檬草的挥发气体成分。结果表明：柠檬草中共鉴定出25种主要挥发性化合物,以碳氢化合物和醛类物为主,包括β-月桂稀（34．34％）、石竹烯（0．493％）、莰烯（0．646％）、D-柠檬烯（0．126％）、1R-α-蒎烯（0．73％）、柠檬醛（26．5％）、3,7二甲基-2,6-辛二稀醛（26．63％）等。经过精制的柠檬草精油含有酮和烃类化合物,主要有：2-十一酮（0．606％）、2-甲基-5-（1-甲基乙基）环己酮（1．83％）、（1S）-6,6-二甲基-二乙基二环-[3,1,1]-庚烷,（0．34％）、1,4-双亚甲基-环已烷,（0．176％）,3-丙基-环已基（0．1667％）。 相似文献
16.
Stochastic differential equation (SDE) models are a promising method for modeling intraindividual change and variability. Applications of SDEs in the social sciences are relatively limited, as these models present conceptual and programming challenges. This article presents a novel method for conceptualizing SDEs. This method uses structural equation modeling (SEM) conventions to simplify SDE specification, the flexibility of SEM to expand the range of SDEs that can be fit, and SEM diagram conventions to facilitate the teaching of SDE concepts. This method is a variation of latent difference scores (McArdle, 2009; McArdle & Hamagami, 2001) and the oversampling approach (Singer, 2012), and approximates the advantages of analytic methods such as the exact discrete model (Oud & Jansen, 2000) while retaining the modeling fiexibility of methods such as latent differential equation modeling (Boker, Neale, & Rausch, 2004). A simulation and empirical example are presented to illustrate that this method can be implemented on current computing hardware, produces good approximations of analytic solutions, and can flexibly accommodate novel models. 相似文献
17.
Xuan Cai Rong-zhang Mai Jing-jing Zou Hong-yan Zhang Xiang-ling Zeng Ri-ru Zheng Cai-yun Wang 《Journal of Zhejiang University. Science. B》2014,15(7):638-648
Objective: Aroma is the core factor in aromatherapy. Sensory evaluation of aromas differed among three sweet osmanthus (Osmanthus fragrans) cultivar groups. The purpose of this study was to investigate the aroma-active compounds responsible for these differences. Methods: Gas chromatography-olfactometry (GC-O) and GC-mass spectrometry (GC-MS) were used to analyze the aroma-active compounds and volatiles of creamy-white (’Houban Yingui’, HBYG), yellow (’Liuye Jingui’, LYJG), and orange (’Gecheng Dangui’, GCDG) cultivars. Results: Seventeen aroma-active compounds were detected among 54 volatiles. trans-β-Ocimene, trans-β-ionone, and linalool, which were major volatiles, were identified as aroma-active, while cis-3-hexenyl butanoate, γ-terpinene, and hexyl butanoate were also aroma-active compounds, although their contents were low. Analysis of the odors was based on the sum of the modified frequency (MF) values of aroma-active compounds in different odor groups. HBYG contained more herb odors, contributed by cis-β-ocimene and trans-β-ocimene, while LYJG had more woody/violet/fruity odors released by trans-β-ionone, α-ionone, and hexyl butanoate. In GCDG, the more floral odors were the result of cis-linalool oxide, trans-linalool oxide, and linalool. Conclusions: Aroma-active compounds were not necessarily only the major volatiles: some volatiles with low content also contributed to aroma. The aroma differences among the three cultivars resulted from variation in the content of different odor groups and in the intensities of aroma-active compounds. 相似文献