| Fining is a method to either clarify or chemically stabilize wine, or to do both. The procedure works by and depends upon both chemistry and gravity. Fining begins by selecting a fining agent appropriate to the desired purpose. The agent must be heavier than both water and alcohol and not soluble in either. The agent is then stirred into the wine to evenly distribute it for best effect.The fining agent ultimately settles to the bottom of the container (usually a tank or barrel), causing small suspended particles to precipitate out along with the agent. Afterwards, the clarified wine is then separated off the settlings (lees) by siphoning (racking). Physical agents work by absorbtion, sucking up the tiny particles as the agent settles towards the bottom. Chemical agents work by adsorbtion, forming chemical bonds with hydrogen elements in the undesired particles. Fining agents include egg white, milk, blood, gelatin (a protein extracted from bones and tendons), carbon, casein (the principal protein constituent of milk and cheese) and isinglass (an extract of sturgeon bladders). Heat stabilization is a fining process that uses bentonite (a clay of hydrated magnesium silicates) to remove protein, which may cloud a wine. Fining agents are intended to precipitate out and be removed, so they do not end up as components of wine, although trace amounts may linger. The majority of wines that are fined are also filtered which would remove even residual traces. Fining can lower high levels of tannin, remove haze, and reduce color. Care needs to be taken to chose the proper fining agent and amount that conforms to the wine style the winemaker wants to achieve. Over-fining can result in wine lacking in qualities such aroma complexity, flavor depth, viscosity, and even aging potential. When the term "unfined" appears on a wine label, it serves as notice that the wine inside may be less than perfectly clear and probably contain more than a usual amount of tannin or sediment. That said, however, wineries are under no legal or moral obligation to reveal for what purpose or whether or not a wine has been fined and there are no legal standards or agencies to define or monitor fining processes. Page created February 8, 2003 | Last Updated April 4, 2006 Except as noted, site design & content © 1999-2006 by Jim LaMar . All rights reserved. |
