Sherry wines polyphenols

Guillen, D.A., Barroso, C.G., and Perez-Bustamante, J.A., Automation of sample preparation as a preliminary stage in the high-performance liquid chromatographic determination of polyphenolic compounds in sherry wines, J. Chromatogr. A, 730, 39, 1996. 

Alonso AM, Castro R, Rodriguez MC, Guillen DA, Barroso CG (2004) Study of the antioxidant power of brandies and vinegars dtaived from Sherry wines and correlation with their content in polyphenols. Food Res Int 37 715—721... 

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. 

In both methods, it is important to separate the juice from the pomace as soon as possible to produce a juice low in tannin and harsh polyphenols, which are undesirable in wines for producing sherry (called shermats in the California wine industry). 

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