Aminoacetophenone in Wines

There are countries (e.g., Italy) where winemaking does not use V. vinifera (hybrid) grapes and commercialization of their wines is not permitted. 2 -Aminoacetophenone (AAP) was identified as the cause of the aging note, so-called hybrid note or foxy smelling , typical of Labruscana grapes and also found in some V. vinifera wines (e.g., Muller-Thurgau, Riesling, and Silvaner) (Rapp et al., 1993). 

Analysis of fermented synthetic media revealed that AAP is also a secondary metabolite of S. cerevisiae yeasts together with o-aminopropiophenone and 3-(o-aminophenyl)-prop-l-en-3-one (Ciolfi et al., 1995). Methylanthranilate also contributes to the typical hybrid-foxy taint of American hybrid and wild vine wines. It was found in some V. vinifera white wines in concentration 0.3 gg/E (Rapp and Versini, 1996). 

For analysis of AAP in wine, an SPE sample preparation method can be performed by using highly cross-linked ethylvinylbenzene-divinylbenzene copolymers (e.g., LiChrolut EN) cartridges. A volume of 50 mL of wine spiked with an internal standard (e.g., acetophenone-d8 or 73-AAP) is passed through the cartridge, then analytes are recovered with 1 mL of dichloromethane. The organic phase is washed with 1 mL of a sodium hydrogen carbonate solution, then dried over anhydrous sodium sulfate. The residual solution is added to 100-pL 

Alternatively, a direct-immersion SPME method with DVB/CAR/ PDMS fiber (50/30 pm, 2 cm length) has been proposed. An aliquot of 15 mL of wine is transferred into a 20-mL vial and equilibrated at 30 °C for 5 min, then the fiber is immerged into the solution for 30 min under stirring. The fiber is then desorbed into the GC injection port at 250 °C (Fan et al., 2007). 

Albagnac, G. (1975). La decarboxylation des acides cinnamiques substitues par les levures, Ann. Technol. Agric., 24,133-141. 

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Schmarr, H-G., GanB, S., Sang, W., and Potouridis, T. (2007). Analysis of 2-aminoacetophenone in wine using a stable isotope dilution assay and multidimensional gas chromatography-mass spectrometry, /. Chrom. A, 1150,78-84. 

Acid hydrolysis compounds 105 Aminoacetophenone in wines 149 Anthocyanin derivatives 200 Anthocyanidins 164 Aroma compounds in grape 97,103,107... 

H., and Schreier, P. 1996. Quantitative analysis of 2-aminoacetophenone in off-flavored wines by stable isotope dilution assay. JAOAC (J. Assoc. Off. Anal. Chem.) Int. 79 583-586. 

Hoenicke, K., Borchert, O., Griming, K., and Simat, T.J. (2002a). Untypical aging off-flavor in wine synthesis of potential degradation compounds of indole-3-acetic acid and kynurenine and their evaluation as precursors of 2-aminoacetophenone, J. Agric. Food Chem., 50,4303-4309. 

Hoenicke, K., Simat, T.J., Steinhart, H., Christoph, N., GeBner, M., and Kohler, H.J. (2002b). Untypical aging off-flavor in wine formation of 2-aminoacetophenone and evaluation of its influencing factors, Anal. Chim. Acta, 458, 29-37. 

Two pathways have been envisaged for the biosynthesis of 2-aminoacetophenone from tryptophan, to explain how it is formed in wine. The first pathway is physicochemical, via indoleacetic acid, while the second is enzymatic, involving cynurease (Rapp et al., 1998 Gebner et al., 1998) (Figure 8.32). 

Many wines with a strong labrusca character have been found to have a methyl anthranilate content well below the apparent odor threshold (JXL). Furthermore the addition of this compound to vinifera wines at very high concentrations does not produce a labrusca aroma nor does it produce a wine with any foxiness. There are small amounts of other anthranilate esters ethyl propyl ..-butyl and the analogous compound Q.-aminoacetophenone in labrusca grapes but there are no data explaining their precise contribution if any to the methyl anthranilate-like aroma. 

N Christoph, M Bauer-Christoph, M Gessner, H-J Kohler, TJ Simat, K Hoenicke. Formation of 2-aminoacetophenone and formylaminoacetophenone in wine by reaction of sulfurous acid with indole-3-acetic acid. Wein-Wissenschaft 53 79-86, 1998. 

A Rapp, G Versini, L Engel. Determination of 2-aminoacetophenone in fermented model wine solutions. Vitis 34 193-194, 1995. 

B Dollmann, A Schmitt, H Kohler, P Schreier. Formation of the untypical aging off-flavor in wine Generation of 2-aminoacetophenone in model studies with Saccharomyces cerevisiae. Wein-Wissenschaft 51 122-125, 1996. 

WR Sponholz, T Huhn. Aging of wine 1,1,6 Trimethyl-1,2-dihydronaphtha-lene (TDN) and 2-aminoacetophenone. In Proceedings of the Fourth International Symposium on Cool Climate Viticulture and Enology. T Henick-Kling, TE Wolf, EM Harkness, eds. Rochester New York State Agricultural Experiment Station, 1996, pp VI-37-57. 

Fan, W., Tsai, I-M., and Qian, M.C. (2007). Analysis of 2-aminoacetophenone by direct-immersion solid-phase microextraction and gas chromatography-mass spectrometry and its sensory impact in Chardonnay and Pinot gris wines, Food Chern., 105,1144-1150. 

The contribution of 2-aminoacetophenone (Figure 8.31) to the prematurely aged aroma of white wines, initially demonstrated in white German wines (Rapp et al, 1993), has now been... 

Dubourdieu and Lavigne (2002) demonstrated the protective effect of lees on the premature aging of Sauvignon Blanc aroma. When these wines are aged under reducing conditions, i.e. on total lees in used barrels, the loss of fruity aroma is limited and the formation of sotolon and 2-aminoacetophenone is attenuated. On the contrary, aging dry white wines in new oak without their lees promotes premature aging (Tables 8.16 and 8.17). 

Table 8.17. Impact of aging conditions (6 months) on sotolon and 2-aminoacetophenone fomiation in a Sauvignon Blanc wine...

The presence of indole or an indole derivative in a food is not always desirable. Some white wines develop an off-flavor described as ...floor polish like... within a few months of storage [33]. The chemical responsible for this unpleasant flavor was identified as 2-aminoacetophenone 16 in 1993 [34]. Reported in a series of papers over the next 10 years, researchers traced the ultimate source of this agent to indole-3-acetic acid 15 that was present in the grapes before harvesting Indole-3-acetic acid itself is derived from another indole L-tryptophan. The proposed mechanism for this transformation is shown in Scheme 14 [35]. 

Table 1 Level of Perceived Atypical Aging Character Compared to o-Aminoacetophenone Level in New York Wines from the Finger Lakes ...

Wines 1-4 are from different wineries, vines, and winemakers wines 4 and 5 are from the same winery, vines, and winemaker, but from different years. There were no extractable amounts of skatole or indole in any of the wines using Twister. ATA, atypical aging OAP, o-aminoacetophenone. 

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