Enhanced red wine aging process Typical red wine aging process Your are here Macro aeration during primary fermentation Using oak during enhanced fermentation Enhanced red fermentation process Typical red fermentation
Press, settle and rack wine
1. Move pomace to press as gently as possible. Bitter/harsh character is extracted from macerated skins (not necessarily skin tannins).

2. Drain and press directly to the tank with quality oak integration system. Or settle, then rack into the tank with quality oak integration system.

3. Rack or micro oxygenate just enough to control sulfides until malolactic fermentation has completed. (Do not add copper after any aerative procedure).

Gently moving drained pomace usually produces a higher percentage of press wine that may be used later, without it adding overtly harsh phenolic tastes. It is commonly believed that grinding skins enhances the extraction of skin tannins, thereby producing excessive harshness.
  However, recent research by Dr Véronique Cheynier, Directeur de Recherches, Institut National de la Recherche Agronomique in Montpellier (INRA), and Elizabeth Waters at the Australian Wine Research Institute (AWRI), have shown this common belief is not accurate. They isolated fractions of skin and seed tannins of average lengths: degree of polymerization (dp) 3, 7 and 15. Sensory evaluation of these fractions by Leigh Francis at AWRI has shown that none of these tannin fractions are bitter. As predicted, they do increase astringency as the polymer size increases, proving that skin tannins are not responsible for the bitterness and harshness in the press fraction of wines. However, there are many other phenolic based compounds which could be responsible (research continuing).
  Copper additions to wine should only be made with forethought! For copper to act as we expect it to, it binds with free thiols or mercaptans and must be added to wine at low redox potentials (reduced conditions). If copper is added too soon after an aerative process, e.g. racking, it will act as a catalyst to form disulfides rather than bind the free thiols or mercaptans. If disulfides are formed, free thiols may reappear later in the life of that wine.