Impact compound, aroma

Fretz C., Luisier J.L., Tominaga T, Dubourdieu D., Amado R. (2005). 3-Mercaptohexanol An aroma impact compound of Retite Arvine wine. Am. J. Enol. Vitic., 56, 407 10. 

To begin with, and in spite of the title of the chapter, most wines do not have genuine impact compounds rather they contain a relatively large number of active-odorants that contribute to a larger or smaller extent to the different aroma nuances of wine. A genuine aroma impact compound is a molecule that is able to transmit entirely its sensory descriptors to a product, to the point that... 

Recently, rotundone was identified as a pepper aroma impact compound in Shiraz grapes (Siebert et al.,2008). Identification was achieved by performing GC-MS analysis of grape juice after purification by solid-phase extraction (SPE) using a styrene-divinylbenzene 500-mg cartridge and elution with n-pentane/ethyl acetate 9 1, followed by solid-phase microextraction (SPME) using a 65-pm polydimethylsilox-ane-divinylbenzene (PDMS/DVB) fiber immersed in the sample for 60 min at 35 °C. J5-Rotundone was used as an internal standard. The structure of the compound is reported in Fig. 4.5. 

Siebert, T.E., Wood, C., Elsey, G.M., and Pollnitz, A.P. (2008). Determination of rotundone, the pepper aroma impact compound, in grapes and wine, J. Agric. Food Chem., 56,3745-3748. 

Blank I., Sen A. and Grosch W. (1992a) Aroma impact compounds of arabica and robusta coffee. Qualitative and quantitative investigations. 14thlnt. Colloq. Chem. Coffee (San Francisco, 14—19.7.1991) (ASIC, 1992), 117-29. 

Holscher W. (1996) Comparison of some aroma impact compounds in roasted coffee and coffee surrogates. R. Soc Chem., Spec. Pub . 197, 239-44. 

Holscher W., Vitzthum O.G. and Steinhart H. (1990) Identification and sensorial evaluation of aroma-impact compounds in roasted Colombian coffee. Cafe, Cacao, The 34, 205-12. 

Lin, J. and R.L. Rouseff, 2001. Characterization of aroma impact compounds in cold-pressed grapefruit oil using time-intensity GC olfactometry and GC MS. 16 457-463. 

Peterson, D.G., G.A.Reineccius, Determination of the aroma impact compounds in heated sweet cream butter. Flavour Fragrance /., 18(4), p. 320, 2003. 

Olivecrona, T, Bengtsson, G. Lipase in milk. In Lipases (Eds. Borgstrijm, B., Brockman, H.L.), p. 205, Elsevier Science Publ., Amsterdam. 1984 Ott, A. Fay, L.B., Chtiintreau, A. Determination and origin of the aroma impact compounds of yoghurt flavor. In Flavour perception. Aroma evaluation (Eds. H.P. Kruse, M. Rothe) Universitat Potsdam, 1997, p. 203... 

By use of standard curves of peak areas versus quantity with solutions of known concentration, it was decided that data reported as microgram component on the SPME fiber gave reliable results and were readily derived from the equilibrium headspace data. Some other reports of SPME using certain model citrus components have included myrcene as one of the components [20]. We opted not to include it, since purchasing pure myrcene standards is not possible. Myrcene polymerizes readily (unstable) and may be difficult to separate from octanal on very nonpolar GC columns. Although it is very aromatic, it is not a strong citrus aroma impact compound. 

R. T. Marsili and N. MUler, Determination of major aroma impact compounds in fermented cucumbers by sohd-phase microextraction-gas chromatography-mass spectrometry-olfactometry detection, J. Chromatogr. Sci. 38 307 (2000). 

Figure 6 Chemical structures of some aroma impact compounds (FD > 128) found in an aroma extract of roast and ground Arabica coffee 2-methyl-3-furanthiol (no. 5),...

Figure 8 Chemical structures of some aroma impact compounds (FD > 12.5) found in the headspace of roast and ground Arabica and Robusta coffee acetaldehyde (no. 1), methanethiol (no. 2), diacetyl (no. 5), 3-methylbutanal (no. 6), 2-methylbutanal (no. 7), 2,3-pentanedione (no. 8), and 3-methyl-2-butene-l-thiol (no. 9). The numbers correspond to those in Table 1.

Table 4 Precursors of Some Aroma Impact Compounds Found in Food...

GC-O of the SDE-SV extract of a commercial meaty/savory flavoring (sample C, Table 6) revealed 15 odor-active components out of about 100 volatiles. However, only six odorants showed ED factors of 2 and higher (Table 7). The meaty/savory note was mainly imparted by odorants containing sulfur. The c -isomer of 2-methyl-3-tetrahydrofuranthiol was also found, but did not contribute to the overall aroma. Identification was mainly based on GC-MS and NMR and was verified by commercially available or synthesized reference compounds. These are essential for unequivocal identification. The chemical structures of the aroma impact compounds identified in the flavoring are shown in Fig. 12. 

I. Blank, A. Sen, and W. Grosch, Aroma impact compounds of Arabica and Robusta coffee. Qualitative and quantitative investigations, Proc. 14th Int. Conf. Coffee Sci. (ASIC 14), San Francisco, 1992, p. 117. 

From a qualitative point of view, the main GC-0 methods seem to be equivalent for determining the impact odorants of a product, with the exception that some peaks can be missed when using only one or two panelists (Fig. 1). The aroma impact compounds of coffee brew found by GC- SNIF (29) were in agreement with those found by AEDA (41). Le Guen et al. compared OSME, AEDA, and GC- SNIF results to determine the most potent odorants of cooked mussels (32). They concluded that the three methods were well correlated. They also observed that GC- SNIE was twice as fast as AEDA and OSME. ... 

A. Ott, L. B. Fay, and A. Chaintreau, Determination and origin of the aroma impact compounds of yogurt flavor, J. Agric. Food Chem. 45 850 (1997). 

Aroma impact compounds that are universal to all varieties of mushrooms include l-octen-3-ol (1 ppb threshold) and l-octen-3-one (0.05 ppb threshold), both of which have been described as having a fresh, wild-mushroom aroma (15). However, l-octen-3-one also possesses a metallic odor, particularly in the context of oxidized oils (34). 

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