挥发性化合物

Abstract(#br)Dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography-quadrupole mass spectrometry analysis (GC- q MS), was used to investigate the aroma profile of different species of passion fruit samples. The performance of five commercially available SPME fibres: 65 μm polydimethylsiloxane/divinylbenzene, PDMS/DVB; 100 μm polydimethylsiloxane, PDMS; 85 μm polyacrylate, PA; 50/30 μm divinylbenzene/carboxen on polydimethylsiloxane, DVB/CAR/PDMS (StableFlex); and 75 μm carboxen/polydimethylsiloxane, CAR/PDMS; was evaluated and compared.

Abstract(#br)In this study, a novel and efficient method based on headspace solid-phase microextraction (HS-SPME), followed by gas chromatography–mass spectrometry (GC–MS), was developed for the analysis of propolis volatile compounds. The HS-SPME procedure, whose experimental parameters were properly optimized, was carried out using a 100\u003cce:hsp sp=\"0.25\"/\u003eμm polydimethylsiloxane (PDMS) fiber.

Headspace solid-phase microextraction (SPME) with an 85 µm Carboxen polydimethylsiloxane (CAR/PDMS) fiber was used to extract volatile compounds, and a gas chromatograph equipped with a mass spectometry detector (GC-MS) was used to identify the volatile compounds in honeys. Thirty-four different volatile compounds from the headspace of honey produced in the central valley of Ñuble Province, Chile, were extracted with fiber coating CAR/PDMS. The identified compounds were: 10 alcohols, 9 acids, 6 ketones, 3 aldehydes, 2 furans, 2 terpenes and 2 lactones.

Analysis of Volatile Compounds in Perilla frutescens var. acuta by Solid Phase MicroextractionPerilla frutescens var. acuta;volatile compound;SPME;This study was conducted to find the appropriate fiber for extraction of volatile compounds from Perilla frutescens var. acuta. by solid phase microextraction (SPME). Two SPME fiber, carboxen/polydimethylsiloxane (CAR/PDMS) and polydimethylsiloxane (PDMS) were used to determine the selectivity of the fibers to the different flavor compounds present in the Perilla frutescens var. acuta.

非洲社区传统的奥帕克啤酒迅速变质，在生产的7天内就被消费。本研究采用搅拌棒吸附萃取技术，GC- HRT测定了南非常见酿造的4种不透明啤酒在7 d货架期内84种挥发性化合物的变化。观察到主要果味酯类在第4天开始增加，并最终减少到第7天，其含量最终低于第1天。醛类急剧减少，第2天低于50 %，第7天几乎无法检测。啤酒货架期常见的啤酒醇类(苯乙醇和3 -甲基-1 -丁醇)减少，而药味不良的酚类(克罗索醇和对甲酚)增加到第7天时的24倍。本研究可能会为非洲农村社区传统的不透明啤酒研究打开未来的研究视角。

非洲社区传统的奥帕克啤酒迅速变质，在生产的7天内就被消费。本研究采用搅拌棒吸附萃取技术，GC- HRT测定了南非常见酿造的4种不透明啤酒在7 d货架期内84种挥发性化合物的变化。观察到主要果味酯类在第4天开始增加，并最终减少到第7天，其含量最终低于第1天。醛类急剧减少，第2天低于50 %，第7天几乎无法检测。啤酒货架期常见的啤酒醇类(苯乙醇和3 -甲基-1 -丁醇)减少，而药味不良的酚类(克罗索醇和对甲酚)增加到第7天时的24倍。本研究可能会为非洲农村社区传统的不透明啤酒研究打开未来的研究视角。

采用基于Arrow固相微萃取装置的新型样品前处理方法，在牛奶样品经气相色谱-质谱( GC-MS )测定前对挥发性有机物( VOCs )进行萃取和预富集。从纤维种类、进样量、萃取温度、萃取时间、搅拌速率、加盐量等方面对固相微萃取( SPME ) Arrow法的实验参数进行了评价。在最佳萃取条件下，将SPME Arrow与传统SPME纤维进行比较，以评价SPME Arrow方法的有效性。对常规SPME程序也在优化条件下进行评价，以便进行适当的方法比较。由于SPME Arrow吸附相体积较大，测定的色谱峰相对于常规SPME纤维具有更高的灵敏度和重现性。碳宽范围( WR ) SPME Arrow /聚二甲基硅氧烷( CAR / PDMS ) SPME Arrow纤维的使用导致比经典SPME装置提高了4 - 5x的因子。此外，常规SPME方法总挥发物的相对标准偏差( RSD )为12.5 %，SPME Arrow方法的RSD为6.2 %。最后，将该新方法成功用于市售牛奶样品的分析。本研究结果表明，SPME Arrow可有效用于复杂食品基质中挥发性有机物的测定。