Gas Chromatography-Olfactometry analysis

Priser, C., Etievant, P. X., Nicklaus, S., and Brun, O. (1997). Representative champagne wine extracts for gas chromatography olfactometry analysis. /. Agric. Food Client. 45,3511-3514. 

Marti, M.P., Mestres, M., Sala, C., Busto, O., and Guasch, J. (2003). Solid-phase microextraction and gas chromatography olfactometry analysis of successively diluted samples. A new approach of the aroma extract dilution analysis applied to the characterization of wine aroma. J. Agric. Food Chem., 51, 7861-7865. 

Ong, P.K.C., Aciee, T.E. Gas chromatography/ olfactometry analysis of Lichee (Litchi chinensis). J. Agric. Food Chem. 46,2282 (1998)... 

A relatively new methodology caEed aroma dEution analysis (ada), which combines aroma dEution and gas chromatography-olfactometry to gain a better understanding of the relative importance of aroma compounds, was recently done for coffee. In a roasted Colombian coffee brew, 41 impact compounds were found with flavor dEution threshold factors (FD) greater than 25, and 26 compounds had FD factors of 100 or above. WhEe the technique permits assessment of the impact of individual compounds, it does not evaluate synergistic effects among compounds (13). 

Maas B, Dietrich A, Mosandl A, Enantioselective capillary gas chromatography — Olfactometry in essential oil analysis, Naturwissenschafien 80 470 72,1993. 

Maas, B., A. Dietrich, and A. Mosandl, Enantioselective Capillary Gas Chromatography— Olfactometry in Essential Oil Analysis. Naturwissenschaften, 1993 80, 470-472. 

G1.6 Solid-Phase Microextraction for Flavor Analysis G1.7 Simulation of Mouth Conditions for Flavor Analysis G1.8 Gas Chromatography/Olfactometry... 

Basic Protocol 1 Gas Chromatography/Olfactometry Using Direct Sniffing Gl.8.1 Basic Protocol 2 Dilution Analysis With Gas Chromatography/... 

Gas chromatography/olfactometry (GC/O) based on dilution analysis (e.g., CharmAna-lysis or Aroma Extraction Dilution Analysis) gives an indication of what compounds are most potent in the aroma of foods. The application of SPME to GC/O dilution analysis can be achieved by varying the thickness of the fiber phase and the length of exposure, resulting in various absorbant volumes. 

It should be kept in mind that most analytical instruments, such as gas chromatographs and mass spectrometers, do not discriminate between volatile compounds that do or do not possess odor activity. Some form of sensory analysis must be conducted in order to select which volatile compounds contribute to the flavor of the foods. Gas chromatography-olfactometry (GC/O) is an important tool to accomplish that task. 

Gas chromatography/olfactometry (GCO) methods have been developed as screening procedures to detect potent odorants in food extracts. The FD-factors or CHARM values determined in food extracts are not consequently an exact measure for the contribution of a single odorant to the overall food flavor for the following reasons. During GCO the complete amount of every odorant present in the extract is volatilized. However, the amount of an odorant present in the headspace above the food depends on its volatility from the food matrix. Furthermore, by AEDA or CHARM analysis the odorants are ranked according to their odor thresholds in air, whereas in a food the relative contribution of an odorant is strongly affected by its odor threshold in the food matrix. The importance of odor thresholds in aroma research has been recently emphazised by Teranishi et al. [58],... 

The method of choice for the analysis of odorants and subsequent identification is gas chromatography-olfactometry (GC—O), a method which combines the separation capability of volatile compounds by GC with the selective and sensitive odor detector human nose (Fuller, Steltenkamp and Tisserand, 1964). A scheme of the set-up can be seen in Figure 8.6. 

In addition to GC-MS, recent studies have focused on the identification and quantitative analysis of impact odorants in botrytized wines using gas chromatography-olfactometry (GC-O) analysis. Sarrazin et al. (2007a) investigated numerous botrytized and nonbotry-tized Sautemes wines. They could identify several key odorants that were responsible for the sensory differences between the wines, notably 3-mercaptohexan-l-ol, various furanons, ethyl-hexanoate, methional, phenylethanol, phenylacetaldehyde, sotolon, p-damascenone, and 2-methyl-3-furanthiol. 

The volatiles of fresh leaves, buds, flowers and fruits were isolated by solvent extraction and analysed by capillary gas chromatography-mass spectrometry. Their odour quality was characterized by gas chromatography-olfactometry—mass spectrometry (HRGC-O-MS) and aroma extract dilution analysis (AEDA). In fresh bay leaves, 1,8-cineole was the major component, together with a-terpinyl acetate, sabinene, a-pinene, P-pinene, P-elemene, a-terpineol, linalool and eugenol. Besides 1,8-cineole and the pinenes, the main components in the flowers were a-eudesmol, P-elemene and P-caryophyllene, in the fruits (EJ-P-ocimene and biclyclogermacrene, and... 

I. Blank, Gas Chromatography-Olfactometry in Food Aroma Analysis. In Flavor, Fragrance, and Odor Analysis, R. Marsili, Ed. Marcel Dekker New York, 2002 pp 297-331. 

Debonneville, C., Orsier, B., Flament, I., and Chaintreau, A. (2002). Improved hardware and software for quick gas chromatography-olfactometry using Charm and GC- SNIF analysis. Anal. Chem., 74, 2345-2351. 

Fan, W.L., and Qian, M.C. (2005). Headspace solid phase microextraction and gas chromatography-olfactometry dilution analysis of young and aged Chinese Yanghe Daqu liquors. J. Agric. Food Chem., 53, 7931-7938. 

Guarrera, N., Campisi, S., and Asmundo, C.N. (2005). Identification of the odorants of two pas-sito wines by gas chromatography-olfactometry and sensory analysis. Am. J. Enol. Vitic., 56, 394-399. 

Le Fur, Y, Mercurio, V., Moio, L., Blanquet, J., and Meunier, J.M. (2003). A new approach to examine the relationships between sensory and gas chromatography-olfactometry data using generalized procrustes analysis applied to Six French Chardonnay wines. J. Agric. Food Chem., 5i, 443-452. 

Lopez, R., Ezpeleta, E., Sanchez, I., Cacho, J., and Ferreira, V. (2004). Analysis of the aroma intensities of volatile compounds released from nuld acid hydrolysates of odourless precursors extracted from TempranUlo and Grenache grapes using gas chromatography-olfactometry. Food Chem., 88, 95-103. 

Miranda-Lopez, R., Libbey, L.M., Watson, B.T., and McDaniel, M.R. (1992). Odor analysis of Knot Noir wines from grapes of different maturities by a gas chromatography-olfactometry technique (osme). J. Food Sci., 57, 985-993 and 1019. 

Cabernet wine comparison. One of the objectives of the study was to identify the odoi active compounds of wines with "Brett" flavor through sensory analysis and gas chromatography-olfactometry (GCO). Wines identified by their respective winemakers as having "Brett" character were evaluated by a trained expert sensory panel also, using the technique CharmAnalysis (92-94) for GCO analysis, along with gas chromatography-mass spectrometry (GC-MS), odor-active compounds were identified by their respective Kovats retention indices (95). Contained below is a... 

Brett flavor in wine The question still remains what is "Brett" flavor Results from our initial work indicates that "Brett" aroma in wine is a complex mixture of odor-active compounds, including acids, alcohols, aldehydes, ketones, esters, and phenolics. Analysis by gas chromatography-olfactometry revealed two predominate odor-active compounds responsible for the Brett flavor in the wines studied isovaleric acid and a second unknown compound other identified odor-active compounds included 2-phenyl ethanol, isoamyl alcohol, cis-2-nonenal, trans-2-nonenal, B-damascenone, ethyl decanoate, guaiacol, 4-ethyl guaiacol, 4-ethyl phenol. Our findings are a snapshot into the much larger picture know as Brett flavor. Ultimately this preliminary investigation requires the descriptive analyses of many more wines to know what odor active compounds describe the flavor know as "Brett". 

Blank, I., Gas chromatography-olfactometry in food aroma analysis. In Techniques for Analyzing Food Aroma (Marsdi, R., ed.), Marcel Dekker, New York, pp. 293-329, 1997. 

Grosch, W., Kerscher, R., Kubickova, J., JageUa, T. (2001) Aroma extract dilution analysis versus aroma extract concentration analysis. In Leland, J.V., Schieberle, R, Buettner, A., Acree, T. (eds.) Gas Chromatography Olfactometry The State of the Art. ACS Symposium Series 782, pp. 138-147... 

Matsui, T, Guth, H., Grosch, W. (1998) A comparative study of potent odorants in peanut, hazelnut, and pumpkin seed oils on the basis of aroma extract dilution analysis (AEDA) and gas chromatography-olfactometry of headspace samples (GCOH). Fett/I.ipid 100. 51-56... 

Gas chromatography-olfactometry (GCO) has been used extensively for the identification of characteristic aroma conq)onents of foods (9,10). Aroma extract dilution analysis (AEDA) is a GCO technique in which serial dilutions (e.g. 1 3) of an aroma extract are evaluated by GCO. In AEDA, the highest dilution at which an odorant is last detected during GCO, so-called flavor dilution (FD) factor, is used as a measure of its odor potency (P). One potential drawback to AEDA is that the technique is limited to the analysis of components of intermediate and low volatility. To overcome this limitation, AEDA results have been con5>lemented by results of GCO of decreasing dynamic headspace (DHS) and decreasing static headspace (GCO-H) san5)les (70,77)... 

It is well known that the aroma extract dilution analysis (AEDA) is a nsefnl method for the recognition of the odor quality and odor intensity of each component." Especially the AEDA is a useful method for the identification of trace amonnts of the component that significantly affects the flavor of tea drinks. The odor intensity of the flavor component is expressed by the flavor dilution (ED) factor, that is, the ratio of the concentration of the flavor component in the initial extract to its concentration in the most dilnte extract in which odor was detected by gas chromatography-olfactometry (GC-0). Therefore, hereafter, from the viewpoint of sensory evalnation, the change in the flavor of tea drink dnring heat processing by AEDA will be mainly discnssed. Furthermore, in order to inhibit flavor deterioration of tea drink, the stndy of flavor precnrsor in a variety of foods, including tea drinks, will be proposed. 

Deibler K.D., Acree T.E. and Lavin E.H. (1998) Aroma analysis of coffee brew by gas chromatography-olfactometry. In Dev. Food Sci., Food Flavours, Morton and Macleod Eds, Elsevier 40, 69-78. 

Semmelroch P. and Grosch W. (1995) Analysis of roasted coffee powders and brews by gas chromatography-olfactometry of headspace samples. Food Sci. Technol. (London) and Lebensm.-Wiss. Techno . 28, 310-13. 

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