(U.S. Patent No. 08/218,920)

Volatile Acidity Reduction

The occasional spoilage of bulk wine by vinegar bacteria results in poorer quality blends, greatly reduced market value and, in some cases, near total loss if the wine must be sold for vinegar stock.

VINOVATION, Inc. has developed a mechanical process for removing volatile acidity from bulk wine. The unit consists of a reverse osmosis device (essentially a pump, feeding wine in tangential flow over a semi-permeable membrane) and an anion exchange column. A skeletal illustration of the process may be seen in the following diagram.


Wine from the tank (1) is transferred via a pump (2) to a reverse osmosis housing (3). As the wine flows past the reverse osmosis membrane (4), a small portion of the fluid diffuses through the membrane. The retentate (5), or that portion of the wine that does not pass through the membrane, is essentially the same as the untreated wine except it has a slightly lower amount of alcohol, water and acetic acid. The permeate (6), or that portion of the wine that does pass through the membrane is a colorless, mostly flavorless liquid that contains only water, alcohol and acetic acid. The permeate (6) is then passed through an anion exchange column (7) which contains an inert resin that binds the acetic acid and lets the alcohol and water pass through. What passes through the column (8) is then recombined with the retentate (5) and returned to the wine tank. In this manner, the acetic acid is slowly removed from the wine without affecting any of the other flavors or aromas of the wine.

The only materials that the wine comes into contact with, outside the normal tanks, hoses and piping used in wine production, is a polyamide membrane used in reverse osmosis and the epoxy resin used in anion exchange. Both of these materials are completely inert, with no trace whatsoever left in the wine, and are commonly used in other areas of wine and food production. They are considered a processing aid, similar to bentonite or diatomaceous earth, which effect a change in the wine itself but then are completely removed.

FAQ for Volatile Acidity Reduction

Will the technique effect wine quality other than V.A.?

Volatile acidity reduction is remarkably gentle on the wine and will not affect the underlying wine quality, other than improving it by removing the V.A. The underlying flavor and aromas will be essentially unchanged. Since you are removing acid from the wine, you will see a corresponding increase in pH and decrease in T.A., and some vintners report a softening in the tannin of the wine, similar to a light egg white fining.

In cases of very high V.A., caused by excessive oxidation, the oxidative character of the wine may be revealed after the V.A. is removed but it is not increased beyond what was in the wine originally.

Over the last 8 years, Vinovation has treated wines from more than 1000 clients representing millions of gallons in 8 countries. Every year, wines that have used the Vinovation technique are voted among the Wine Spectator’s Top 100.

How large or small a lot can you do? 

There is no upper volume limit and Vinovation can treat amounts as small as 100 gallons. Contact Vinovation for more information.

Do I have to bring the wine to Vinovation or can it be done at my winery?

Volatile Acidity removal can be done on-site, provided sufficient power, refrigeration and cooperage are available. Contact Vinovation for details on these requirements. However, unless you have wine volume in excess of 40,000 gallons or more, treatment at your winery is usually much more expensive.

Can I treat just a portion of the wine and blend back?

In most cases this is not practical, you will need to treat the lot. It is very expensive and much more detrimental to wine quality to remove V.A. below levels normally found in sound wines.


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Vinovation, Inc
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