Additional gases may be present as well and include carbon dioxide and volatile acids.

The kidneys are used to eliminate fixed acids from the metabolism whereas the lungs take care of volatile acids.

The kidneys are used to eliminate fixed acids from the metabolism whereas the lungs take care of volatile acids.

The content of volatile acids is an important parameter for the taste of the wine.

When the body needs to increase the elimination of volatile acids, it does so simply by increasing the rate of respiration.

Volatile acid: ≤ 10 mg/kg (as acetic acid

This wine may be recirculated through the system to remove yet more of the volatile acidity.

NOTE The presence of volatile fatty acids and volatile acidic oxidation products prevents accurate measurement.

This produces a purified permeate, which is depleted in volatile acidity (which is passed through with the raw permeate), but contains other components desirable for the wine.

The purified permeate is then recombined with the retentate from the reverse osmosis column, and the result is wine with the volatile acidity and little else removed.