Fino wine

M. Alvarez, I. M. Moreno, A. Jos, A. M. Camean and A. G. Gonzalez, Differentiation of two Andalusian DO fino wines according to their metal content from ICP-OES by using supervised pattern recognition methods, Microchem. J., 87(1), 2007, 72-76. 

As noted previously, the main types of sherry (fino, oloroso, and amon-tillado) are produced employing different conditions. These differences result in significantly different polyphenolic composition. In the case of fino-type sherries, the layer of yeast that grows in the surface of the wine (flor velum) preserves its pale color. The velum limits the exposure of the wine from oxygen (Baron et ah, 1997). Hence, fino wines mature in a markedly reductive environment. 

Fino wine, which is the best known type of biologically aged wine, is obtained by using the criaderas and solera system, which essentially involves the periodic homogenization of wines of different age. This process is complex and expensive, but produces wines of uniform quality over time. Also, it makes the vintage notion meaningless. 

Fino wines are only produced by biological aging. The aerobic metabolism of flor yeasts causes changes in the aroma fraction that endows them wine with their typical flavour. In addition, they protect these wines against browning and allow them to retain their pale colour for years. 

Amontillado wines are obtained in a two-step process involving biological aging under the same conditions to those of fino wines, followed by fortification and oxidative aging as in oloroso wines. Amontillado wines are thus the oldest and most valued of the three sherry types by virtue of their acquiring a more complex flavour than the other two. 

The OSs used as an analytical tool for the study of Fino wines have already been defined in Table 1 and were calculated by adding the OAVs of all the corresponding compounds (including those with OAVs < 1). From a theoretical point of view, these compounds did not directly contribute to the aroma profile, although some authors consider that these compounds may enhance some aromatic notes due to their synergistic effects with other odorant compoxmds (Freitas et al., 1999 Lopez et al., 1999). 

The aroma compounds studied during the biological ageing of Fino wines belong to different chemical families. The higher alcohols determined were methanol, 2-butanol, 1-propanol, isobutanol, 1-butanol, isoamyl alcohols, 1-pentanol, 3- and 4-methyl-l-pentanol, 1-hexanol, 3-ethoxy-l-propanol, Z-3-hexenol, 1-heptanol, 1-octanol, furfuryl alcohol, 2, 3-butanediol, 1-decanol, benzyl alcohol and phenethyl alcohol. 

Figure 4a provides a plot of the values obtained for the OSs of the commercial wines studied. The figure shows the mean value for each series and those calculated, taking into account the standard deviations. In this mode, any value included between the highest and lowest in each series would be acceptable for a typical Fino wine. As can be seen, the fruity, balsamic, chemical and spicy series were those that contributed most markedly to the aroma profile. 

The contribution of wood to the aroma of aged Fino wine has been clearly shown in earlier experiments carried out to shorten the biological ageing time (Cortes et al., 1999 Moyano et al., 2002). 

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