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Headspace Solid Phase Microextraction (headspace + solid_phase_microextraction)
Selected AbstractsCOMPARISON OF HEADSPACE SOLID PHASE MICROEXTRACTION AND XAD-2 METHODS TO EXTRACT VOLATILE COMPOUNDS PRODUCED BY SACCHAROMYCES DURING WINE FERMENTATIONSJOURNAL OF FOOD QUALITY, Issue 1 2006JEFFRI C. BOHLSCHEID ABSTRACT A modified headspace solid phase microextraction (HS-SPME) method was compared with Amberlite® XAD-2 resin for the extraction of volatile compounds. In the HS-SPME method, volatiles were extracted using an 85 ,m polyacrylate fiber from wines that contained a standardized amount of ethanol (10% v/v), NaCl (0.325 g/mL) and internal standards (dodecanol and nonanoic acid). Both extraction procedures yielded high relative recoveries (>92%) and reproducibilities (coefficient of variations , 11%) for the different higher alcohols, esters and medium-chain fatty acids. Overall, limits of detection for the HS-SPME and XAD-2 methods were below sensory threshold concentrations. HS-SPME and XAD-2 performed similarly in the analysis of a Riesling wine; however, the HS-SPME method did not require organic solvents and was generally quicker to perform. In applying the HS-SPME method, differences in concentrations of volatile compounds produced in Riesling and Chenin blanc wines by 11 different yeast strains were noted. [source] SPME , A valuable tool for investigation of flower scentJOURNAL OF SEPARATION SCIENCE, JSS, Issue 8 2003Petr Barták Abstract A novel Headspace Solid Phase Microextraction (HS-SPME) protocol is proposed for the analysis of floral scent. Volatile compounds emitted from the flower are collected on a Carboxen/PDMS fiber for 1 hour, transferred to the GC, and analyzed by GC/MS. The method completely eliminates the use of organic solvents, does not require special instrumentation, and may readily be performed in the field without access to mains electricity and other energy supplies. The method is robust, sensitive, and reduces the sampling stress on the investigated plant. Since enzymatic reactions in living flowers may cause changes in the composition of emitted fragrance, dried rosemary (Rosmarinus officinalis L.) was used as a stable standard for the method development and optimization. In addition, grape wine was also suggested as homogeneous, bio-compatible, and relatively stable standard of pronounced and typical scent for the same purpose. The optimized method was used for the comparative investigation of the fragrances emitted by two different species , Lathyrus vernus (L.) and Orchis pallens (L.). Several monoterpenes (C10 compounds) were found as the main fragrance components of lathyrus, while sesquiterpenes (C15 compounds) were typical for the orchid. [source] Characterization of the aroma-active compounds in five sweet cherry cultivars grown in Yantai (China)FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2010Shu Yang Sun Abstract This study was conducted to determine the aroma-active compounds of five sweet cherry cultivars grown in Yantai region, China, viz. ,Lapins', ,Rainier', ,Stella', ,Hongdeng' and ,Zhifuhong'. The samples were extracted by headspace solid phase microextraction (HS,SPME) and analysed by gas chromatography,mass spectrometry (GC,MS) on DB-wax and DB-5 columns. A total of 52 volatiles were identified. Among these, hexanal, (E)-2-hexenal, 1-hexanol, (E)-2-hexen-1-ol, benzaldehyde and benzyl alcohol were the main volatile compounds in the five cherries. Furthermore, the aroma compounds of five cherry samples were evaluated using a combination of HS,SPME and GC,olfactometry (GC,O) dilution analysis, and a total of 40 aroma-active compounds were identified. The results suggested that hexanal, (E)-2-hexenal, (Z)-3-hexenal, nonanal, benzaldehyde and geranylacetone (FD , 16), responsible for the green, orange, almond and floral characters of the cherries, were the potentially important common odorants in these cherry cultivars. Benzyl alcohol and linalool were significant aroma compounds in most cherries, with the exception of ,Stella' and ,Rainier'. In addition, (E,Z)-2,6-nonadienal (cucumber-like odour) could be important to ,Hongdeng' and ,Zhifuhong', and (E,E)-2,4-nonadienal (fatty odour) probably made great contributions to the aromas in ,Lapins' and ,Stella'. From the present result, it was concluded that the aroma profiles were similar in the five cherry cultivars, but significant variation was found in the contributions of these compounds to each cherry. Copyright © 2010 John Wiley & Sons, Ltd. [source] COMPARISON OF HEADSPACE SOLID PHASE MICROEXTRACTION AND XAD-2 METHODS TO EXTRACT VOLATILE COMPOUNDS PRODUCED BY SACCHAROMYCES DURING WINE FERMENTATIONSJOURNAL OF FOOD QUALITY, Issue 1 2006JEFFRI C. BOHLSCHEID ABSTRACT A modified headspace solid phase microextraction (HS-SPME) method was compared with Amberlite® XAD-2 resin for the extraction of volatile compounds. In the HS-SPME method, volatiles were extracted using an 85 ,m polyacrylate fiber from wines that contained a standardized amount of ethanol (10% v/v), NaCl (0.325 g/mL) and internal standards (dodecanol and nonanoic acid). Both extraction procedures yielded high relative recoveries (>92%) and reproducibilities (coefficient of variations , 11%) for the different higher alcohols, esters and medium-chain fatty acids. Overall, limits of detection for the HS-SPME and XAD-2 methods were below sensory threshold concentrations. HS-SPME and XAD-2 performed similarly in the analysis of a Riesling wine; however, the HS-SPME method did not require organic solvents and was generally quicker to perform. In applying the HS-SPME method, differences in concentrations of volatile compounds produced in Riesling and Chenin blanc wines by 11 different yeast strains were noted. [source] | ||||||||||